====================================================================================================
    PICO-8 User Manual
====================================================================================================

PICO-8 v0.2.4b
https://www.pico-8.com
(c) Copyright 2014-2022 Lexaloffle Games LLP
Author: Joseph White // hey@lexaloffle.com

PICO-8 is built with:
 
    SDL2 http://www.libsdl.org
    Lua 5.2 http://www.lua.org  // see license.txt
    ws281x by jgarff            // see license.txt
    GIFLIB http://giflib.sourceforge.net/
    WiringPi http://wiringpi.com/
    libb64 by Chris Venter
    miniz by Rich Geldreich

Latest version of this manual (as html, txt) and other resources:

https://www.lexaloffle.com/pico-8.php?page=resources

:: Welcome to PICO-8!

    PICO-8 is a fantasy console for making, sharing and playing tiny games and other computer  
    programs. When you turn it on, the machine greets you with a shell for typing in Lua programs  
    and provides simple built-in tools for creating sprites, maps and sound.

    The harsh limitations of PICO-8 are carefully chosen to be fun to work with, encourage small 
    but expressive designs and hopefully to give PICO-8 cartridges their own particular look and  
    feel.

:: Specifications

    Display: 128x128, fixed 16 colour palette
    Input:   6-button controllers
    Carts:   32k data encoded as png files
    Sound:   4 channel, 64 definable chip blerps
    Code:    Lua (max 8192 tokens of code) 
    Sprites: Single bank of 128 8x8 sprites (+128 shared)
    Map:     128x32 8-bit cells (+128x32 shared)

====================================================================================================
    Getting Started
====================================================================================================

----------------------------------------------------------------------------------------------------
 Keys
----------------------------------------------------------------------------------------------------

    ALT+ENTER:  Toggle Fullscreen
    ALT+F4:     Fast Quit (Windows)
    CTRL-Q:     Fast Quit (Mac, Linux)
    CTRL-R:     Reload / Run / Restart cartridge
    CTRL-S:     Quick-Save working cartridge
    CTRL-M:     Mute / Unmute Sound
    ENTER / P:  Pause Menu (while running cart)

    Player 1 default keys: Cursors + ZX / NM / CV
    Player 2 default keys: SDFE + tab,Q / shift A

    To change the default keys use the KEYCONFIG utility from inside PICO-8:

    > KEYCONFIG

----------------------------------------------------------------------------------------------------
 Hello World
----------------------------------------------------------------------------------------------------

    After PICO-8 boots, try typing some of these commands followed by enter:

        > PRINT("HELLO WORLD")
        > RECTFILL(80,80,120,100,12)
        > CIRCFILL(70,90,20,14)
        > FOR I=1,4 DO PRINT(I) END

    (Note: PICO-8 only displays upper-case characters -- just type normally without capslock!)

    You can build up an interactive program by using commands like this in the code editing mode 
    along with two special callback functions @_UPDATE and @_DRAW. For example, the following 
    program allows you to move a circle around with the cursor keys. Press Esc to switch to the 
    code editor and type or copy & paste the following code:

        X = 64  Y = 64
        FUNCTION _UPDATE()
            IF (BTN(0)) THEN X=X-1 END
            IF (BTN(1)) THEN X=X+1 END
            IF (BTN(2)) THEN Y=Y-1 END
            IF (BTN(3)) THEN Y=Y+1 END
        END
 
        FUNCTION _DRAW()
            CLS(5)
            CIRCFILL(X,Y,7,14)
        END

    Now press Esc to return to the console and type RUN (or press CTRL-R) to see it in action. 
    Please refer to the demo cartridges for more complex programs (type INSTALL_DEMOS).

    If you want to store your program for later, use the SAVE command:

    > SAVE PINKCIRC

    And to load it again:

    > LOAD PINKCIRC

----------------------------------------------------------------------------------------------------
 Example Cartridges
----------------------------------------------------------------------------------------------------

    These cartridges are included with PICO-8 and can be installed by typing:

    > INSTALL_DEMOS
    > CD DEMOS
    > LS	
     
    HELLO      Greetings from PICO-8
    API        Demonstrates most PICO-8 functions
    JELPI      Platform game demo w/ 2p support 
    CAST       2.5D Raycaster demo
    DRIPPY     Draw a drippy squiggle
    WANDER     Simple walking simulator
    COLLIDE    Example wall and actor collisions

    To run a cartridge, open PICO-8 and type:

    > LOAD JELPI
    > RUN

    Press escape to stop the program, and once more to enter editing mode.

    A small collection of BBS carts can also be installed to /GAMES with: 

    > INSTALL_GAMES

----------------------------------------------------------------------------------------------------
 File System
----------------------------------------------------------------------------------------------------

    These commands can be used to manage files and directories (folders):

    LS          list the current directory
    CD BLAH     change directory
    CD ..       go up a directory
    CD /        change back to top directory (on PICO-8's virtual drive)
    MKDIR BLAH  make a directory
    FOLDER      open the current directory in the host operating system's file browser

    LOAD BLAH  load a cart from the current directory SAVE BLAH  save a cart to the current 
    directory

    If you want to move files around, duplicate them or delete them, use the FOLDER  command and do 
    it in the host operating system.

    The default location for PICO-8's drive is:

    Windows: C:/Users/Yourname/AppData/Roaming/pico-8/carts
    OSX: /Users/Yourname/Library/Application Support/pico-8/carts
    Linux: ~/.lexaloffle/pico-8/carts

    You can change this and other settings in pico-8/config.txt

    Tip: The drive directory can be mapped to a cloud drive (provided by Dropbox, Google Drive or 
    similar) in order to create a single disk shared between PICO-8 machines spread  across 
    different host machines.

----------------------------------------------------------------------------------------------------
 Loading and Saving
----------------------------------------------------------------------------------------------------

    When using LOAD and SAVE, the .P8 extension can be omitted and is added automatically.

    > SAVE FOO
    SAVED FOO.P8

    Cartridge files can also be dragged and dropped into PICO-8's window to load them.

    Using .p8.png filename extension will write the cartridge in a special image format that looks 
    like a cartridge. Using .p8.rom" writes in a raw 32k binary format.

    Use a filename of "@CLIP" to load or save to the clipboard.

    Once a cartridge has been loaded or saved, it can also be quick-saved with CTRL-S

    :: Saving .p8.png carts with a text label and preview image

        To generate a label image saved with the cart, run the program first and press CTRL-7 to 
        grab whatever is on the screen. The first two lines of the program starting with '--' are 
        also  drawn to the cart's label.

        -- OCEAN DIVER LEGENDS
        -- BY LOOPY

    :: Code size restrictions for .p8.png / .p8.rom formats

        When saving in .png or .rom format, the compressed size of the code must be less than 15360 
        bytes so that the total data is <= 32k.

        To find out the current size of your code, use the INFO command. The compressed size limit  
        is not enforced for saving in .p8 format.

----------------------------------------------------------------------------------------------------
 Using an External Text Editor
----------------------------------------------------------------------------------------------------

    It is possible to edit .p8 files directly with a separate text editor. Using CTRL-R to run a 
    cartridge will automatically re-load the file if:

        1. There are no unsaved changes in the PICO-8 editors, AND<br> 2. The file differs in 
        content from the last loaded version.

    If there are changes to both the cart on disk and in the editor, a notification is displayed:

        DIDN'T RELOAD; UNSAVED CHANGES

    Alternatively, .lua text files can be modified in a separate editor and then included into the  
    cartridge's code each time it is run using @{#INCLUDE} (in the desired code location):

        #INCLUDE YOURFILE.LUA

----------------------------------------------------------------------------------------------------
 Backups
----------------------------------------------------------------------------------------------------

    When quitting without saving changes, or overwriting an existing file, a backup of the 
    cartridge  is saved to {appdata}/pico-8/backup. An extra copy of the current cartridge can also 
    be saved to the same folder by typing BACKUP.

    To open the backups folder in the host operating system's file browser, use:

    > FOLDER BACKUPS

    It is then possible to drag and drop files into the PICO-8 window to load them.

----------------------------------------------------------------------------------------------------
 Configuration
----------------------------------------------------------------------------------------------------

        PICO-8 reads configuration settings from config.txt at the start of each session, and saves 
        it on exit (so you should edit config.txt when PICO-8 is not running).

        The location of the config.txt file depends on the host operating system:

        Windows: C:/Users/Yourname/AppData/Roaming/pico-8/config.txt
        OSX: /Users/Yourname/Library/Application Support/pico-8/config.txt
        Linux: ~/.lexaloffle/pico-8/config.txt

        Use the -home switch (below) to use a different path to store config.txt and other data.

        Some settings can be changed while running PICO-8 by typing CONFIG SETTING VALUE. (type 
        CONFIG by itself for a list)

    :: Commandline parameters

        // note: these override settings found in config.txt

        pico8 [switches] [filename.p8]

        -width n                set the window width 
        -height n               set the window height 
        -windowed n             set windowed mode off (0) or on (1)
        -volume n               set audio volume 0..256
        -joystick n             joystick controls starts at player n (0..7)
        -pixel_perfect n        1 for unfiltered screen stretching at integer scales (on by default)
        -preblit_scale n        scale the display by n before blitting to screen (useful with -pixel_perfect 0)
        -draw_rect x,y,w,h      absolute window coordinates and size to draw pico-8's screen 
        -run filename           load and run a cartridge
        -x filename             execute a PICO-8 cart headless and then quit (experimental!)
        -export param_str       run EXPORT command in headless mode and exit (see notes under export)
        -p param_str            pass a parameter string to the specified cartridge
        -splore                 boot in splore mode
        -home path              set the path to store config.txt and other user data files
        -root_path path         set the path to store cartridge files
        -desktop path           set a location for screenshots and gifs to be saved
        -screenshot_scale n     scale of screenshots.  default: 3 (368x368 pixels)
        -gif_scale n            scale of gif captures. default: 2 (256x256 pixels)
        -gif_len n              set the maximum gif length in seconds (1..120)
        -gui_theme n            use 1 for a higher contrast editor colour scheme
        -timeout n              how many seconds to wait before downloads timeout (default: 30)
        -software_blit n        use software blitting mode off (0) or on (1)
        -foreground_sleep_ms n  how many milliseconds to sleep between frames.
        -background_sleep_ms n  how many milliseconds to sleep between frames when running in background
        -accept_future n        1 to allow loading cartridges made with future versions of PICO-8
        -global_api n           1 to leave api functions in global scope (useful for debugging)

:: Controller Setup

    PICO-8 uses the SDL2 controller configuration scheme. It will detect common controllers on 
    startup and also looks for custom mappings in sdl_controllers.txt in the same directory  as 
    config.txt. sdl_controllers.txt has one mapping per line.

    To generate a custom mapping string for your controller, use either the controllermap program 
    that comes with SDL2, or try http://www.generalarcade.com/gamepadtool/

    To find out the id of your controller as it is detected by SDL2, search for "joysticks" or 
    "Mapping" in log.txt after running PICO-8. This id may vary under different operating systems. 
    See: https://www.lexaloffle.com/bbs/?tid=32130

    To set up which keyboard keys trigger joystick buttons presses, use KEYCONFIG.

----------------------------------------------------------------------------------------------------
 Screenshots and GIFS
----------------------------------------------------------------------------------------------------

    While a cartridge is running use:

        CTRL-6 Save a screenshot to desktop
        CTRL-7 Capture cartridge label image
        CTRL-8 Start recording a video
        CTRL-9 Save GIF video to desktop (8 seconds by default)

    You can save a video at any time (it is always recording); CTRL-8 simply resets the video 
    starting point. To record more than 8 seconds, use the CONFIG command (maximum: 120)

        CONFIG GIF_LEN 60

    If you would like the recording to reset every time (to create a non-overlapping sequence), 
    use:

        CONFIG GIF_RESET_MODE 1

    The gif format can not match 30fps exactly, so PICO-8 instead uses the closest match: 33.3fps.

    If you have trouble saving to the desktop, try configuring an alternative desktop path in 
    config.txt

----------------------------------------------------------------------------------------------------
 Sharing Cartridges
----------------------------------------------------------------------------------------------------

    There are three ways to share carts made in PICO-8:

        1. Share the .p8 or .p8.png file directly with other PICO-8 users

            Type FOLDER to open the current folder in your host operating system.

        2. Post the cart on the Lexaloffe BBS to get a web-playable version

            http://www.lexaloffle.com/pico-8.php?page=submit

        3. Export the cartridge to a stand-alone html/js or native binary player (see the exporters 
        section for details)

----------------------------------------------------------------------------------------------------
 SPLORE
----------------------------------------------------------------------------------------------------

    SPLORE is a built-in utility for browsing and organising both local and bbs (online) 
    cartridges. Type SPLORE [enter] to launch it, or launch PICO-8 with -splore. 

    It is possible to control SPLORE entirely with a joystick:

    LEFT and RIGHT to navigate lists of cartridges
    UP AND DOWN to select items in each list
    X,O or MENU to launch the cartridge

    While inside a cart, press MENU to favourite a cartridge or exit to splore. If you're using a 
    keyboard, it's also possible to press F to favourite an item while it is selected in the 
    cartridge list view.

    When viewing a list of BBS carts, use the top list item to re-download a list of cartridges. If 
    you are offline, the last downloaded list is displayed, and it is still possible to play any 
    cartridges you have downloaded.

    If you have installed PICO-8 on a machine with no internet access, you can also use 
    INSTALL_GAMES to add a small selection of pre-installed BBS carts to /games

====================================================================================================
    Editing Tools
====================================================================================================

    Press ESC to toggle between console and editor.<br> Click editing mode tabs at top right to 
    switch or press ALT+LEFT/RIGHT.	

----------------------------------------------------------------------------------------------------
    Code Editor
----------------------------------------------------------------------------------------------------

    Hold shift to select (or click and drag with mouse)
    CTRL-X, C, V to cut copy or paste selected
    CTRL-Z, Y to undo, redo
    CTRL-F to search for text in the current tab
    CTRL-G to repeat the last search again
    CTRL-L to jump to a line number
    CTRL-UP, DOWN to jump to start or end
    ALT-UP, DOWN to navigate to the previous, next function
    CTRL-LEFT, RIGHT to jump by word
    CTRL-W,E to jump to start or end of current line
    CTRL-D to duplicate current line
    TAB to indent a selection (shift to un-indent)
    CTRL-B to comment / uncomment selected block

    To enter special characters that represent buttons (and other glyphs), use SHIFT-L,R,U,D,O,X 
    There are 3 additional font entry modes that can be toggled:

        CTRL_J Hiragana   // type romaji equivalents (ka, ki, ku..)
        CTRL-K Katakana   // + shift-0..9 for extra symbols
        CTRL-P Puny font  // hold shift for the standard font

        By default, puny font characters are encoded as unicode replacements when copying/pasting, 
        and both upper and lower case ASCII characters are pasted as regular PICO-8 characters. To 
        copy/paste puny characters as uppercase ASCII, make sure puny mode (CTRL-P) is on.

    :: Code Tabs

        Click the [+] button at the top to add a new tab. Navigate tabs by left-clicking, or with 
        CTRL-TAB, SHIFT-CTRL-TAB. To remove the last tab, delete any contents and then moving off 
        it (CTRL-A, DEL, CTRL-TAB)

        When running a cart, a single program is generated by concatenating all tabs in order.

    :: Code Limits

        The number of code tokens is shown at the bottom right. One program can have a maximum of 
        8192 tokens. Each token is a word (e.g. variable name) or operator. Pairs of brackets, and 
        strings each count as 1 token. commas, periods, LOCALs, semi-colons, ENDs, and comments are 
        not counted.

        Right click to toggle through other stats (character count, compressed size). If a limit is 
        reached, a warning light will flash. This can be disabled by right-clicking.

----------------------------------------------------------------------------------------------------
    Sprite Editor
----------------------------------------------------------------------------------------------------

    The sprite editor is designed to be used both for sprite-wise editing and for freeform  
    pixel-level editing. The sprite navigator at the bottom of the screen provides an 8x8 
    sprite-wise  view into the sprite sheet, but it is possible to use freeform tools (pan, select) 
    when dealing with larger or oddly sized areas.

    :: Draw Tool

        Click and drag on the sprite to plot pixels, or use RMB to select the colour under the 
        cursor.

        All operations apply only to the visible area, or the section if there is one.

        Hold CTRL to search and replace a colour.

    :: Stamp Tool

        Click to stamp whatever is in the copy buffer. Hold CTRL to treat colour 0 (black) as 
        transparent.

    :: Select Tool (shortcut: SHIFT or S)

        Click and drag to create a rectangular selection. To remove the selection, press ENTER or 
        click anywhere.

        If a pixel-wise selection is not present, many operations are instead applied to a 
        sprite-wise selection, or the visible view. To select sprites, shift-drag in the sprite 
        navigator. To select the sprite sheet press CTRL-A (repeat to toggle off the bottom half 
        shared with map data)

    :: Pan Tool (shortcut: SPACE)

        Click and drag to move around the sprite sheet.

    :: Fill Tool

        Fill with the current colour. This applies only to the current selection, or the visible 
        area if there is  no selection.

    :: Shape Tools

        Click the tool button to cycle through: oval, rectangle, line options.

        Hold CTRL to get a filled oval or rectangle.<br> Hold SHIFT to snap to circle, square, or 
        low-integer-ratio line.

    :: Extra keys

        CTRL-Z:   Undo
        CTRL-C/X: Copy/Cut selected area or selected sprites
        CTRL-V:   Paste to current sprite location
        Q/A,W/Z:  Switch to previous/next sprite
        1,2:      Switch to previous/next colour
        TAB:      Toggle fullscreen view
        Mousewheel or < and > to zoom (centered in fullscreen)
        CTRL-H to toggle hex view (shows sprite index in hexadecimal)

    :: Operations on selected area or selected sprites

        F: Flip sprite horizontally
        V: Flip sprite vertically
        R: Rotate (requires a square selection)
        Cursor keys to shift (loops if sprite selection)
        DEL/BACKSPACE to clear selected area

    :: Sprite Flags

        The 8 coloured circles are sprite flags for the current sprite. These  have no particular 
        meaning, but can be accessed using the @FGET() / @FSET() functions. They are indexed from 0 
        starting from the left.

        See @FSET() for more information.

    :: Loading .png files into the sprite sheet

        To load a png file of any size into the sprite sheet, first select the sprite that should 
        be the top-left corner destination, and then either type "IMPORT IMAGE_FILE.PNG" or drag 
        and drop the image file into the PICO-8 window. In both cases, the image is colour-fitted 
        to the current display palette.

----------------------------------------------------------------------------------------------------
    Map Editor
----------------------------------------------------------------------------------------------------

    The PICO-8 map is a 128x32 (or 128x64 using shared space) block of 8-bit values. Each value is 
    shown in the editor as a reference to a sprite (0..255), but you can of course use the data to 
    represent whatever you like.

    WARNING: The second half of the sprite sheet (banks 2 and 3), and the bottom half of the map 
    share the same cartridge space. It's up to you how you use the data, but be aware that drawing 
    on the second half of the sprite sheet could clobber data on the map and vice versa.

    The tools are similar to the ones used in sprite editing mode. Select a sprite and click and 
    drag to paint values into the map.	

    To draw multiple sprites, select from sprite navigator with shift+drag To copy a block of 
    values, use the selection tool and then stamp tool to paste To pan around the map, use the pan 
    tool or hold space Q,W to switch to previous/next sprite Mousewheel or < and > to zoom 
    (centered in fullscreen) CTRL-H to toggle hex view (shows tile values and sprite index in 
    hexadecimal)

    To move sprites in the sprite sheet without breaking references to them in the map:

        1. Select the area of the map you would like to alter (defaults to the top half of the map)
            // press ctrl-A twice to select the full map including shared memory
        2. Select the sprites you would like to move (while still in map view), and press Ctrl-X
        3. Select the destination sprite (also while still in map view) and press Ctrl-V

        // Note: this operation modifies the undo history for both the map and sprite editors, but 
        // PICO-8 will try to keep them in sync where possible. Otherwise, changes caused by moving 
        // map sprites can be reverted by also manually undoing in the sprite editor.

----------------------------------------------------------------------------------------------------
    SFX Editor
----------------------------------------------------------------------------------------------------

    There are 64 SFX ("sound effects") in a cartridge, used for both sound and music.

    Each SFX has 32 notes, and each note has:
        A frequency   (C0..C5)
        An instrument (0..7)
        A volume      (0..7)
        An effect     (0..7)

    Each SFX also has these properties:

            A play speed (SPD) : the number of 'ticks' to play each note for.
                // This means that 1 is fastest, 3 is 3x as slow, etc.
         
            Loop start and end : this is the note index to loop back and to
                // Looping is turned off when the start index >= end index

        When only the first of the 2 numbers is used (and the second one is 0), it is taken to mean 
        the number of notes to be played. This is normally not needed for sound effects (you can 
        just leave the remaining notes empty), but is useful for controlling music playback.

    There are 2 modes for editing/viewing a SFX: Pitch mode (more suitable for sound effects) and 
    tracker mode (more suitable for music). The mode can be changed using the top-left buttons, or 
    toggled with TAB.

:: Pitch Mode

        Click and drag on the pitch area to set the frequency for each note, using the currently 
        selected instrument (indicated by colour).

        Hold shift to apply only the selected instrument.
        Hold CTRL to snap entered notes to the C minor pentatonic scale.
        Right click to grab the instrument of that note.

:: Tracker Mode

        Each note shows: frequency octave instrument volume effect
        To enter a note, use q2w3er5t6y7ui zsxdcvgbhnjm (piano-like layout)
        Hold shift when entering a note to transpose -1 octave .. +1 octave
        New notes are given the selected instrument/effect values
        To delete a note, use backspace or set the volume to 0

        Click and then shift-click to select a range that can be copied (CTRL-C) and pasted 
        (CTRL-V). Note that only the selected attributes are copied. Double-click to select all 
        attributes of a single note.

        Navigation:
            PAGEUP/DOWN or CTRL-UP/DOWN to skip up or down 4 notes
            HOME/END to jump to the first or last note
            CTRL-LEFT/RIGHT to jump across columns

:: Controls for both modes

        - + to navigate the current SFX
        SPACE to play/stop
        SHIFT-SPACE to play from the current SFX quarter (group of 8 notes)
        A to release a looping sample
        Left click or right click to increase / decrease the SPD or LOOP values
            // Hold shift when clicking to increase / decrease by 4
            // Alternatively, click and drag left/right or up/down
        Shift-click an instrument, effect, or volume to apply to all notes.

:: Effects

    0 none
    1 slide          //  Slide to the next note and volume
    2 vibrato        //  Rapidly vary the pitch within one quarter-tone
    3 drop           //  Rapidly drop the frequency to very low values
    4 fade in        //  Ramp the volume up from 0
    5 fade out       //  Ramp the volume down to 0
    6 arpeggio fast  //  Iterate over groups of 4 notes at speed of 4
    7 arpeggio slow  //  Iterate over groups of 4 notes at speed of 8

    If the SFX speed is <= 8, arpeggio speeds are halved to 2, 4

:: Filters

    Each SFX has 5 filter switches that can be accessed while in tracker mode:

    NOIZ:      Generate pure white noise (applies only to instrument 6)
    BUZZ:      Various alterations to the waveform to make it sound more buzzy
    DETUNE-1:  Detunes a second voice to create a flange-like effect
    DETUNE-2:  Various second voice tunings, mostly up or down an octave
    REVERB:    Apply an echo with a delay of 2 or 4 ticks
    DAMPEN:    Low pass filter at 2 different levels

    When BUZZ is used with instrument 6, and NOIZ is off, pure brown noise is generated.

----------------------------------------------------------------------------------------------------
    Music Editor
----------------------------------------------------------------------------------------------------

    Music in PICO-8 is controlled by a sequence of 'patterns'. Each pattern is a list of 4 numbers 
    indicating which SFX will be played on that channel.

:: Flow control

    Playback flow can be controlled using the 3 buttons at the top right.

    When a pattern has finished playing, the next pattern is played unless:

    - there is no data left to play (music stops)
    - a STOP command is set on that pattern (the third button)
    - a LOOP BACK command is set (the 2nd button), in which case the music player searches
        back for a pattern with the LOOP START command set (the first button) or returns to
        pattern 0 if none is found.

    When a pattern has SFXes with different speeds, the pattern finishes playing when the left-most 
    non-looping channel has finished playing. This can be used to set up double-time drum beats or 
    unusual polyrhythms.

    For time signatures like 3/4 where less than 32 rows should be played before jumping to the 
    next pattern, the length of a SFX can be set by adjusting only the first loop position and 
    leaving the second one as zero. This will show up in the sfx editor as "LEN" (for "Length") 
    instead of "LOOP".

:: Copying and Pasting Music

    To select a range of patterns: click once on the first pattern in the pattern  navigator, then 
    shift-click on the last pattern. Selected patterns can be copied  and pasted with CTRL-C and 
    CTRL-V. When pasting into another cartridge, the SFX  that each pattern points to will also be 
    pasted (possibly with a different index)  if it does not already exist.

:: SFX Instruments

    In addition to the 8 built-in instruments, custom instruments can be defined using  the first 8 
    SFX. Use the toggle button to the right of the instruments to select an  index, which will show 
    up in the instrument channel as green instead of pink.

    When an SFX instrument note is played, it essentially triggers that SFX, but alters  the note's 
    attributes:

        Pitch is added relative to C2
        Volume is multiplied
        Effects are applied on top of the SFX instrument's effects
        Any filters that are on in the SFX instrument are enabled for that note

    For example, a simple tremolo effect could be implemented by defining an instrument  in SFX 0 
    that rapidly alternates between volume 5 and 2. When using this instrument to play a note, the 
    volume can further be altered as usual (via the volume channel or using the fade in/out 
    effects). In this way, SFX instruments can be used to control  combinations of detailed changes 
    in volume, pitch and texture.

    SFX instruments are only retriggered when the pitch changes, or the previous note has zero 
    volume. This is useful for instruments that change more slowly over time. For example: a bell 
    that gradually fades out. To invert this behaviour, effect 3 (normally 'drop') can be used when 
    triggering the note. All other effect values	have  their usual meaning when triggering SFX 
    instruments.	

====================================================================================================
 Exporters / Importers
====================================================================================================

The EXPORT command can be used to generate png, wav files and stand-alone html and native binary 
cartridge applications. The output format is inferred from the filename extension (e.g. .png).

You are free to distribute and use exported cartridges and data as you please, provided  that you 
have permission from the cartridge author and contributors.

:: Sprite Sheet (.png)

    > IMPORT BLAH.PNG   -- EXPECTS 128X128 PNG AND COLOUR-FITS TO THE PICO-8 PALETTE
    > EXPORT BLAH.PNG   -- USE THE "FOLDER" COMMAND TO LOCATE THE EXPORTED PNG

    When importing, -x and -y switches can be used to specify the target location in pixels: -s can 
    be used to shrink the image (3 means scale from 384x384 -> 128x128)

    > IMPORT BLAH.PNG -X 16 -Y 16

:: SFX and Music (.wav)

    To export music from the current pattern (when editor mode is MUSIC), or the current SFX:

    > EXPORT FOO.WAV  

    To export all SFXs as foo0.wav, foo1.wav .. foo63.wav:

    > EXPORT FOO%D.WAV

:: Cartridges (.p8, .p8.png, .p8.rom)

    Using EXPORT to save a cartridge is the same as using SAVE, but without changing the current 
    working cartridge. This can be useful for example, to save a copy in .p8.png format for 
    distribution without accidentally continuing to make changes to that file instead of the 
    original .p8 file.

    EXPORT can also be used to perform cartridge file format conversions from commandline. For 
    example, from a Linux shell:

    > pico8 foo.p8 -export foo.p8.png

----------------------------------------------------------------------------------------------------
    Web Applications (.html)
----------------------------------------------------------------------------------------------------

    To generate a stand-alone html player (mygame.html, mygame.js):

    > EXPORT MYGAME.HTML

    Or just the .js file:

    > EXPORT MYGAME.JS

    Use -f to write the files to a folder called mygame_html, using index.html instead of 
    mygame.html

    > EXPORT -F MYGAME.HTML

    Optionally provide a custom html template with the -p switch:

    > EXPORT MYGAME.HTML -P ONE_BUTTON

    This will use the file {application data}/pico-8/plates/one_button.html as the html shell,  
    replacing a special string "##js_file##" (without quotes), with the .js filename, and 
    optionally replacing the string "##label_file##" with the cart's label image as a data url.

    Use -w to export as .wasm + .js:

    > EXPORT -W MYGAME.HTML

    When exported as .wasm, the page needs to be served by a webserver, rather than just opening it 
    directly from the local file system in a browser. For most purposes, the default .js export is 
    fine, but .wasm is slightly smaller and faster.

----------------------------------------------------------------------------------------------------
    Binary Applications (.bin)
----------------------------------------------------------------------------------------------------

    To generate stand-alone executables for Windows, Linux (64-bit), Mac and Raspberry Pi:

    > EXPORT MYGAME.BIN

    By default, the cartridge label is used as an icon with no transparency.  To specify an icon 
    from the sprite sheet, use -i and optionally -s and/or -c  to control the size and 
    transparency.

        -I N  Icon index N with a default transparent colour of 0 (black).
        -S N  Size NxN sprites. Size 3 would be produce a 24x24 icon.
        -C N  Treat colour N as transparent. Use 16 for no transparency.

    For example, to use a 2x2 sprite starting at index 32 in the sprite sheet,  using colour 12 as 
    transparent:

        > EXPORT -I 32 -S 2 -C 12 MYGAME.BIN

    To include an extra file in the output folders and archives, use the -E switch:

        > EXPORT -E README.TXT MYGAME.BIN 

    Windows file systems do not support the file metadata needed to create a Linux or Mac 
    executable. PICO-8 works around this by exporting zip files in a way that preserves the file 
    attributes. It is therefore recommended that you distribute the outputted zip files as-is to 
    ensure users on other operating systems can run them. Otherwise, a Linux user who then 
    downloads the binaries may need to "chmod +x mygame"  the file to run it, and Mac user would 
    need to "chmod +x mygame.app/Contents/MacOS/mygame"

----------------------------------------------------------------------------------------------------
    Uploading to itch.io
----------------------------------------------------------------------------------------------------

    If you would like to upload your exported cartridge to itch.io as playable html:

        1. From inside PICO-8: EXPORT -F MYGAME.HTML
        2. Create a new project from your itch dashboard.
        3. Zip up the folder and upload it (set "This file will be played in the browser")
        4. Embed in page, with a size of 750px x 680px.
        5. Set "Mobile Friendly" on (default orientation) and "Automatically start on page load" on.
            // no need for the fullscreen button as the default PICO-8 template has its own.
        6. Set the background (BG2) to something dark (e.g. #232323) and the text to something light (#cccccc)

----------------------------------------------------------------------------------------------------
    Exporting Multiple Cartridges
----------------------------------------------------------------------------------------------------

    Up to 16 cartridges can be bundled together by passing them to EXPORT, when generating 
    stand-alone html or native binary players.

    > EXPORT MYGAME.HTML DAT1.P8 DAT2.P8 GAME2.P8

    During runtime, the extra carts can be accessed as if they were local files:

    RELOAD(0,0,0X2000, "DAT1.P8") -- LOAD SPRITESHEET FROM DAT1.P8
    LOAD("GAME2.P8")              -- LOAD AND RUN ANOTHER CART

    Exported cartridges are unable to load and run BBS cartridges e.g. via LOAD("#FOO")

----------------------------------------------------------------------------------------------------
    Running EXPORT from the host operating system
----------------------------------------------------------------------------------------------------

    Use the -export switch when launching PICO-8 to run the exporter in headless mode. File paths 
    are relative to the current directory rather than the PICO-8 file system.

    Parameters to the EXPORT command are passed along as a single (lowercase) string:

    pico8 mygame.p8 -export "-i 32 -s 2 -c 12 mygame.bin dat0.p8 dat1.p8"

====================================================================================================
    Lua Syntax Primer
====================================================================================================

PICO-8 programs are written using Lua syntax, but do not use the standard Lua library. The 
following is a brief summary of essential Lua syntax.

For more details, or to find out about proper Lua, see www.lua.org.

:: Comments

    -- USE TWO DASHES LIKE THIS TO WRITE A COMMENT
    --[[ MULTI-LINE
    COMMENTS ]]

:: Types and assignment

    Types in Lua are numbers, strings, booleans and tables:

    NUM = 12/100
    S = "THIS IS A STRING"
    B = FALSE
    T = {1,2,3}

    Numbers in PICO-8 are all 16:16 fixed point. They range from -32768.0 to 32767.99999

    Hexadecimal notation with optional fractional parts can be used:

    ?0x11        -- 17
    ?0x11.4000   -- 17.25

    Numbers written in decimal are rounded to the closest fixed point value. To see the 32-bit 
    hexadecimal representation, use PRINT(TOSTR(VAL,TRUE)):

    ?TOSTR(-32768,TRUE)      -- 0x8000.0000 
    ?TOSTR(32767.99999,TRUE) -- 0X7FFF.FFFF

    Dividing by zero evaluates to 0x7fff.ffff if positive, or -0x7fff.ffff if negative. 

:: Conditionals

    IF NOT B THEN
        PRINT("B IS FALSE")
    ELSE
        PRINT("B IS NOT FALSE")
    END

    -- with ELSEIF

    IF X == 0 THEN
        PRINT("X IS 0")
    ELSEIF X < 0 THEN
        PRINT("X IS NEGATIVE")
    ELSE
        PRINT("X IS POSITIVE")
    END

    IF (4 == 4) THEN PRINT("EQUAL") END
    IF (4 ~= 3) THEN PRINT("NOT EQUAL") END
    IF (4 <= 4) THEN PRINT("LESS THAN OR EQUAL") END
    IF (4 > 3) THEN PRINT("MORE THAN") END

:: Loops

    Loop ranges are inclusive:

    FOR X=1,5 DO
        PRINT(X)
    END
    -- PRINTS 1,2,3,4,5

    X = 1
    WHILE(X <= 5) DO
        PRINT(X)
        X = X + 1
    END

    FOR X=1,10,3 DO PRINT(X) END   -- 1,4,7,10

    FOR X=5,1,-2 DO PRINT(X) END  -- 5,3,1

:: Functions and Local Variables

    Variables declared as LOCAL are scoped to their containing block of code (for example, inside a 
    FUNCTION, a FOR loop, or IF THEN END statement).

    Y=0 
    FUNCTION PLUSONE(X)
        LOCAL Y = X+1
        RETURN Y
    END
    PRINT(PLUSONE(2)) -- 3
    PRINT(Y)          -- 0

:: Tables

    In Lua, tables are a collection of key-value pairs where the key and value types can both  be 
    mixed. They can be used as arrays by indexing them with integers.

    A={} -- CREATE AN EMPTY TABLE
    A[1] = "BLAH"
    A[2] = 42
    A["FOO"] = {1,2,3}

    Arrays use 1-based indexing by default:

    > A = {11,12,13,14}
    > PRINT(A[2]) -- 12

    But if you prefer 0-based arrays, just write something the zeroth slot:

    > A = {[0]=10,11,12,13,14}

    Tables with 1-based integer indexes are special though. The length of such an array can be 
    found with the # operator, and PICO-8 uses such arrays to implement ADD, DEL, DELI, ALL and 
    FOREACH functions.

    > PRINT(#A)   -- 4
    > ADD(A, 15)
    > PRINT(#A)   -- 5

    Indexes that are strings can be written using dot notation

    PLAYER = {}
    PLAYER.X = 2 -- is equivalent to PLAYER["X"]
    PLAYER.Y = 3

    See the @{Table_Functions} section for more details.

:: PICO-8 Shorthand

    PICO-8 also allows several non-standard, shorter ways to write common patterns.

    1. IF THEN END statements, and WHILE THEN END can be written on a single line with:

    IF (NOT B) I=1 J=2

    Is equivalent to:

    IF NOT B THEN I=1 J=2 END

    Note that brackets around the short-hand condition are required.

    2. Assignment operators

    Shorthand assignment operators can also be used if the whole statement is on one line. They can 
    be constructed by appending a '=' to any binary operator, including arithmetic (+=, -= ..), 
    bitwise (&=, |= ..) or the string concatenation operator (..=)

    A += 2   -- EQUIVALENT TO: A = A + 2

    // note that the LHS appears twice, so for TBL[FN()]+=1, FN() will be called twice.

    3. != operator

    Not shorthand, but pico-8 also accepts != instead of ~= for "not equal to"

    PRINT(1 != 2) -- TRUE
    PRINT("FOO" == "FOO") -- TRUE (STRING ARE INTERNED)

====================================================================================================
    PICO-8 Program Structure
====================================================================================================

    When a PICO-8 programs runs, all of the code from tabs is concatenated (from left to right) and 
    executed. It is possible to provide your own main loop manually, but typically PICO-8 programs 
    use 3 special functions that, if defined by the author, are called during program execution:


        _UPDATE() -- Called once per update at 30fps.


        _DRAW()   -- Called once per visible frame


        _INIT()   -- Called once on program startup.

    A simple program that uses all three might look this:

    FUNCTION _INIT()
        -- ALWAYS START ON WHITE
        COL = 7
    END
     
    FUNCTION _UPDATE()
        -- PRESS X FOR A RANDOM COLOUR 
        IF (BTNP(5)) COL = 8 + RND(8) 
    END
     
    FUNCTION _DRAW()
        CLS(1)
        CIRCFILL(64,64,32,COL)
    END

    _DRAW() is normally called at 30fps, but if it can not complete in time, PICO-8 will attempt to 
    run at 15fps and call _UPDATE() twice per visible frame to compensate.

:: Running PICO-8 at 60fps


    _UPDATE60() 

    When _UPDATE60() Is defined instead of _UPDATE(), PICO-8 will run in 60fps mode:

    - both _UPDATE60() and _DRAW() are called at 60fps<br> - half the PICO-8 CPU is available per 
    frame before dropping down to 30fps

    Note that not all host machines are capable of running at 60fps. Older machines, and / or web 
    versions might also request PICO-8 to run at 30 fps (or 15 fps), even when the PICO-8 CPU is 
    not over capacity. In this case, multiple _UPDATE60 calls are made for every _DRAW call in the 
    same way.

:: #INCLUDE

    Source code can be injected into a program at cartridge boot (but not during runtime), using 
    "#INCLUDE FILENAME", where FILENAME is either a plaintext file (containing Lua code), a tab 
    from another cartridge, or all tabs from another cartridge:

        #INCLUDE SOMECODE.LUA
        #INCLUDE ONETAB.P8:1
        #INCLUDE ALLTABS.P8

    When the cartridge is run, the contents of each included file is treated as if it had been 
    pasted into the editor in place of that line.

        - Filenames are relative to the current cartridge (so, need to save first)<br> - Includes 
        are not performed recursively.<br> - Normal character count and token limits apply.

    When a cartridge is saved as .P8.PNG, or exported to a binary, any included files are  
    flattened and saved with the cartridge so that there are no external dependencies.

    #INCLUDE can be used for things like:

        - Sharing code between cartridge (libraries or common multi-cart code)<br> - Using an 
        external code editor without needing to edit the .p8 file directly.<br> - Treating a 
        cartridge as a data file that loads a PICO-8 editing tool to modify it.<br> - Loading and 
        storing data generated by an external (non-PICO-8) tool.

:: Quirks of PICO-8

    Common gotchas to watch out for:

    - The bottom half of the sprite sheet and bottom half of the map occupy the same memory. // 
    Best use only one or the other if you're unsure how this works.

    - PICO-8 numbers have limited accuracy and range; the minimum step between numbers is 
    approximately 0.00002 (0x0.0001), with a range of -32768 (-0x8000) to approximately 32767.99999 
    (0x7fff.ffff)<br> // If you add 1 to a counter each frame, it will overflow after around 18 
    minutes!

    - Lua arrays are 1-based by default, not 0-based. FOREACH starts at TBL[1], not TBL[0].

    - @COS() and @SIN() take 0..1 instead of 0..PI*2, and @SIN() is inverted.

    - @SGN(0) returns 1.

:: CPU

    Although PICO-8 does not have a clearly defined CPU, there is a virtual CPU speed of 8MHz, 
    where each lua vm instruction costs around 2 cycles. Built-in operations like drawing sprites 
    also have a CPU cost. This means that a PICO-8 cartridge made on a host machine with a powerful 
    CPU can still be guaranteed to run (reasonably) well on much slower machines, and to not drain 
    too much battery on phones / when running on the web.

    To view the CPU load while a cartridge is running, press CTRL-P to toggle a CPU meter, or print  
    out @STAT(1) at the end of each frame.

====================================================================================================
    API Reference
====================================================================================================

    PICO-8 is built on the Lua programming language, but does not include the Lua standard library. 
    Instead, a small api is offered in keeping with PICO-8's minimal design and limited screen 
    space. For an example program that uses most of the api functions, see /DEMOS/API.P8 

    Functions are written here as:

    FUNCTION_NAME(PARAMETER, [OPTIONAL_PARAMETER])

    Note that PICO-8 does not have upper or lower case characters -- if you are editing a .p8 or 
    .lua file directly, function names should all be in lower case.

----------------------------------------------------------------------------------------------------
    System
----------------------------------------------------------------------------------------------------

    System functions called from commandline can omit the usual brackets and string quotes. For 
    example, instead of LOAD("BLAH.P8"), it is possible to write:

    >LOAD BLAH.P8 


    LOAD(FILENAME, [BREADCRUMB], [PARAM_STR])

    SAVE(FILENAME)

        Load or save a cartridge

        When loading from a running cartridge, the loaded cartridge is immediately run with 
        parameter string PARAM_STR (accessible with STAT(6)), and a menu item is inserted and named 
        BREADCRUMB, that returns the user to the previous cartridge.

        Filenames that start with '#' are taken to be a BBS cart id, that is immediately downloaded 
        and run:

        > LOAD("#MYGAME_LEVEL2", "BACK TO MAP", "LIVES="..LIVES)

        If the id is the cart's parent post, or a revision number is not specified, then the latest 
        version is fetched. BBS carts can be loaded from other BBS carts or local carts, but not 
        from  exported carts. 


    FOLDER

        Open the carts folder in the host operating system.


    LS

    DIR

        List files in the current directory. When called from a running program, returns a list  of 
        all .p8 and .p8.png files in the same directory.


    RUN([PARAM_STR])

        Run from the start of the program.

        RUN() Can be called from inside a running program to reset.

        When PARAM_STR is supplied, it can be accessed during runtime with STAT(6)


    STOP([MESSAGE])

        Stop the cart and optionally print a message.


    RESUME

        Resume the program. Use R for short.

        Use a single "." from the commandline to advance a single frame. This enters frame-by-frame 
        mode, that can be read with stat(110). While frame-by-frame mode is active, entering an 
        empty command (by pressing enter) advances one frames.


    ASSERT(CONDITION, [MESSAGE])

        If CONDITION is false, stop the program and print MESSAGE if it is given. This can be 
        useful for debugging cartridges, by ASSERT()'ing that things that you expect to be true are 
        indeed true.

        ASSERT(ADDR >= 0 AND ADDR <= 0x7FFF, "OUT OF RANGE")
        POKE(ADDR, 42) -- THE MEMORY ADDRESS IS OK, FOR SURE!


    REBOOT

        Reboot the machine Useful for starting a new project


    RESET()

        Reset the values in RAM from 0x5f00..0x5f7f to their default values.  This includes the 
        palette, camera position, clipping and fill pattern. If you get lost at the command prompt 
        because the draw state makes viewing text  impossible, try typing RESET! It can also be 
        called from a running program.


    INFO()

        Print out some information about the cartridge: Code size, tokens, compressed size

        Also displayed:

            UNSAVED CHANGES   When the cartridge in memory differs to the one on disk
            EXTERNAL CHANGES  When the cartridge on disk has changed since it was loaded
                (e.g. by editing the program using a separate text editor)


    FLIP()

        Flip the back buffer to screen and wait for next frame. This call is not needed when there 
        is a @_DRAW() or @_UPDATE() callback defined, as the flip is performed automatically. But 
        when using a custom main loop, a call to FLIP is normally needed:

        ::_::
        CLS()
        FOR I=1,100 DO
            A=I/50 - T()
            X=64+COS(A)*I
            Y=64+SIN(A)*I
            CIRCFILL(X,Y,1,8+(I/4)%8)
        END
        FLIP()GOTO _

        If your program does not call FLIP before a frame is up, and a @_DRAW() callback is not in 
        progress, the current contents of the back buffer are copied to screen.


    PRINTH(STR, [FILENAME], [OVERWRITE], [SAVE_TO_DESKTOP])

        Print a string to the host operating system's console for debugging.

        If filename is set, append the string to a file on the host operating system (in the 
        current directory by default -- use FOLDER to view).

        Setting OVERWRITE to true causes that file to be overwritten rather than appended.

        Setting SAVE_TO_DESKTOP to true saves to the desktop instead of the current path.

        Use a filename of "@clip" to write to the host's clipboard.

        Use stat(4) to read the clipboard, but the contents of the clipboard are only available 
        after pressing CTRL-V during runtime (for security).


    TIME()

    T()

        Returns the number of seconds elapsed since the cartridge was run.

        This is not the real-world time, but is calculated by counting the number of times


        _UPDATE or @_UPDATE60 is called. Multiple calls of TIME() from the same frame return

        the same result.


    STAT(X)

        Get system status where X is:

        0  Memory usage (0..2048)
        1  CPU used since last flip (1.0 == 100% CPU)
        4  Clipboard contents (after user has pressed CTRL-V)
        6  Parameter string
        7  Current framerate

        46..49  Index of currently playing SFX on channels 0..3 50..53  Note number (0..31) on 
        channel 0..3 54      Currently playing pattern index 55      Total patterns played 56      
        Ticks played on current pattern 57      (Boolean) TRUE when music is playing   80..85  UTC 
        time: year, month, day, hour, minute, second 90..95  Local time   100     Current 
        breadcrumb label, or nil 110		Returns true when in frame-by-frame mode

    Audio values 16..26 are the legacy version of audio state queries 46..56. It only operates on 
    the current state of the audio mixer, which changes only ~20 times a second (depending on the 
    host sound driver and other factors). 46..56 instead stores a history of mixer state at each 
    tick to give a higher resolution estimate of the currently audible state.


    EXTCMD(CMD_STR)

        Special system command, where CMD_STR is a string:

            "pause"         request the pause menu be opened
            "reset"         request a cart reset
            "go_back"       follow the current breadcrumb (if there is one)
            "label"         set cart label
            "screen"        save a screenshot
            "rec"           set video start point
            "rec_frames"    set video start point in frames mode (see below)
            "video"         save a .gif to desktop
            "audio_rec"     start recording audio
            "audio_end"     save recorded audio to desktop
            "shutdown"      quit cartridge (from exported binary)
            "folder"        open current working folder on the host operating system
            "set_filename"  set the filename for screenshots / gifs
            "set_title"     set the host window title

        :: Recording GIFs

            EXTCMD("REC"), EXTCMD("VIDEO") is the same as using ctrl-8, ctrl-9 and saves a gif to 
            the desktop using the current GIF_SCALE setting (use CONFIG GIF_SCALE to change).

            Two additional parameters can be used to override these defaults:

                EXTCMD("VIDEO", 4)    -- SCALE *4 (512 X 512)
                EXTCMD("VIDEO", 0, 1) -- DEFAULT SCALING, SAVE TO USER DATA FOLDER

            The user data folder can be opened with EXTCMD("FOLDER") and defaults to the same path 
            as the cartridge, or {pico-8 appdata}/appdata/appname for exported binaries.

            Due to the nature of the gif format, all gifs are recorded at 33.3fps, and frames 
            produced by PICO-8 are skipped or duplicated in the gif to match roughly what the user 
            is seeing. To record exactly one frame each time @FLIP() is called, regardless of the 
            runtime framerate or how long it took to generate the frame, use:

                EXTCMD("REC_FRAMES")

            The default filename for gifs (and screenshots) is foo_%d, where foo is the name of the 
            cartridge, and %d is a number starting at 0 and automatically incremented until a file 
            of that name does not exist. Use EXTCMD("SET_FILENAME","FOO") to override that default. 
            If the custom filename includes "%d", then the auto- incrementing number behaviour is 
            used, but otherwise files are written even if  there is an existing file with the same 
            name.

----------------------------------------------------------------------------------------------------
    Graphics
----------------------------------------------------------------------------------------------------

    PICO-8 has a fixed capacity of 128 8x8 sprites, plus another 128 that overlap with the bottom 
    half of the map data ("shared data"). These 256 sprites are collectively called the sprite 
    sheet, and can be thought of as a 128x128 pixel image.

    All of PICO-8's drawing operations are subject to the current draw state. The draw state 
    includes a camera position (for adding an offset to all coordinates), palette mapping  (for 
    recolouring sprites), clipping rectangle, a drawing colour, and a fill pattern.

    The draw state is reset each time a program is run, or by calling @RESET().

    Colour indexes:
     
         0  black   1  dark_blue   2  dark_purple   3  dark_green  
         4  brown   5  dark_gray   6  light_gray    7  white
         8  red     9  orange     10  yellow       11  green       
        12  blue   13  indigo     14  pink         15  peach


    CLIP(X, Y, W, H, [CLIP_PREVIOUS])

        Sets the screen's clipping region in pixels CLIP() to reset When clip_previous is true, 
        clip the new clipping region by the old one.


    PSET(X, Y, [COL])

        Sets the pixel at x, y to colour index COL (0..15).

        When COL is not specified, the current draw colour is used.

        FOR Y=0,127 DO
            FOR X=0,127 DO
                PSET(X, Y, X*Y/8)
            END
        END


    PGET(X, Y)

        Returns the colour of a pixel at (X, Y), or 0 when (X, Y) is outside the clipping region.

        WHILE (TRUE) DO
            X, Y = RND(128), RND(128)
            DX, DY = RND(4)-2, RND(4)-2
            PSET(X, Y, PGET(DX+X, DY+Y))
        END


    SGET(X, Y)

    SSET(X, Y, [COL])

        Get or set the colour (COL) of a sprite sheet pixel.


    FGET(N, [F])

    FSET(N, [F], VAL)

        Get or set the value (VAL) of sprite N's flag F.

        F is the flag index 0..7.

        VAL is TRUE or FALSE.

        The initial state of flags 0..7 are settable in the sprite editor, so can be used to create 
        custom sprite attributes. It is also possible to draw only a subset of map tiles by 
        providing a mask in @MAP().

        When F is omitted, all flags are retrieved/set as a single bitfield.

        FSET(2, 1 | 2 | 8)   -- SETS BITS 0,1 AND 3
        FSET(2, 4, TRUE)     -- SETS BIT 4
        PRINT(FGET(2))       -- 27 (1 | 2 | 8 | 16)


    PRINT(STR, X, Y, [COL])

    PRINT(STR, [COL])

        Print a string STR and optionally set the draw colour to COL.

        Shortcut: written on a single line, ? can be used to call print without brackets: 

            ?"HI"

        When X, Y are not specified, a newline is automatically appended. This can be omitted by 
        ending the string with an explicit termination control character:

            ?"THE QUICK BROWN FOX\0"

        Additionally, when X, Y are not specified, printing text below 122 causes  the console to 
        scroll. This can be disabled during runtime with POKE(0x5f36,0x40).

        PRINT returns the right-most x position that occurred while printing. This can be used to 
        find out the width of some text by printing it off-screen:

            W = PRINT("HOGE", 0, -20) -- returns 16

        See @{Appendix A} (P8SCII) for information about control codes and custom fonts.


    CURSOR(X, Y, [COL])

        Set the cursor position.

        If COL is specified, also set the current colour.


    COLOR([COL])

        Set the current colour to be used by drawing functions.

        If COL is not specified, the current colour is set to 6


    CLS([COL])

        Clear the screen and reset the clipping rectangle.

        COL defaults to 0 (black)


    CAMERA([X, Y])

        Set a screen offset of -x, -y for all drawing operations

        CAMERA() to reset


    CIRC(X, Y, R, [COL])

    CIRCFILL(X, Y, R, [COL])

        Draw a circle or filled circle at x,y with radius r

        If r is negative, the circle is not drawn


    OVAL(X0, Y0, X1, Y1, [COL])

    OVALFILL(X0, Y0, X1, Y1, [COL])

        Draw an oval that is symmetrical in x and y (an ellipse), with the given bounding 
        rectangle.


    LINE(X0, Y0, [X1, Y1, [COL]])

        Draw a line from (X0, Y0) to (X1, Y1)

        If (X1, Y1) are not given, the end of the last drawn line is used.


    RECT(X0, Y0, X1, Y1, [COL])

    RECTFILL(X0, Y0, X1, Y1, [COL])

        Draw a rectangle or filled rectangle with corners at (X0, Y0), (X1, Y1).


    PAL(C0, C1, [P])

        PAL() swaps colour c0 for c1 for one of three palette re-mappings (p defaults to 0):

        0: Draw Palette

            The draw palette re-maps colours when they are drawn. For example, an orange flower 
            sprite can be drawn as a red flower by setting the 9th palette value to 8:

            PAL(9,8)     -- draw subsequent orange (colour 9) pixels as red (colour 8) SPR(1,70,60) 
            -- any orange pixels in the sprite will be drawn with red instead

            Changing the draw palette does not affect anything that was already drawn to the 
            screen.

        1: Display Palette

            The display palette re-maps the whole screen when it is displayed at the end of a 
            frame. For example, if you boot PICO-8 and then type PAL(6,14,1), you can see all of 
            the gray (colour 6) text immediate change to pink (colour 14) even though it has 
            already been drawn. This is useful for screen-wide effects such as fading in/out.

        2: Secondary Palette

            Used by @FILLP() for drawing sprites. This provides a mapping from a single 4-bit 
            colour index to two 4-bit colour indexes.

        PAL()  resets all palettes to system defaults (including transparency values) PAL(P) resets 
        a particular palette (0..2) to system defaults


    PAL(TBL, [P])

        When the first parameter of pal is a table, colours are assigned for each entry. For 
        example, to re-map colour 12 and 14 to red:

            PAL({[12]=9, [14]=8})

        Or to re-colour the whole screen shades of gray (including everything that is already 
        drawn):

            PAL({1,1,5,5,5,6,7,13,6,7,7,6,13,6,7,1}, 1)

        Because table indexes start at 1, colour 0 is given at the end in this case.


    PALT(C, [T])

        Set transparency for colour index to T (boolean) Transparency is observed by @SPR(), 
        @SSPR(), @MAP() AND @TLINE()

        PALT(8, TRUE) -- RED PIXELS NOT DRAWN IN SUBSEQUENT SPRITE/TLINE DRAW CALLS

        PALT() resets to default: all colours opaque except colour 0

        When C is the only parameter, it is treated as a bitfield used to set all 16 values. For 
        example: to set colours 0 and 1 as transparent:

        PALT(0B1100000000000000)


    SPR(N, X, Y, [W, H], [FLIP_X], [FLIP_Y])

        Draw sprite N (0..255) at position X,Y

        W (width) and H (height) are 1, 1 by default and specify how many sprites wide to blit.

        Colour 0 drawn as transparent by default (see @PALT())

        When FLIP_X is TRUE, flip horizontally.

        When FLIP_Y is TRUE, flip vertically.


    SSPR(SX, SY, SW, SH, DX, DY, [DW, DH], [FLIP_X], [FLIP_Y]]

        Stretch an rectangle of the sprite sheet (sx, sy, sw, sh) to a destination rectangle on the 
        screen (sx, sy, dw, dh). In both cases, the x and y values are coordinates (in pixels) of 
        the rectangle's top left corner, with a width of w, h.

        Colour 0 drawn as transparent by default (see @PALT())

        dw, dh defaults to sw, sh

        When FLIP_X is TRUE, flip horizontally.

        When FLIP_Y is TRUE, flip vertically.


    FILLP(P)

        The PICO-8 fill pattern is a 4x4 2-colour tiled pattern observed by: @CIRC() @CIRCFILL() 
        @RECT() @RECTFILL() @OVAL() @OVALFILL() @PSET() @LINE()

        P is a bitfield in reading order starting from the highest bit. To calculate the value of P 
        for a desired pattern, add the bit values together:

            .-----------------------.
            |32768|16384| 8192| 4096|
            |-----|-----|-----|-----|
            | 2048| 1024| 512 | 256 |
            |-----|-----|-----|-----|
            | 128 |  64 |  32 |  16 |
            |-----|-----|-----|-----|
            |  8  |  4  |  2  |  1  |
            '-----------------------'

        For example, FILLP(4+8+64+128+  256+512+4096+8192) would create a checkerboard pattern.

        This can be more neatly expressed in binary: FILLP(0b0011001111001100).

        The default fill pattern is 0, which means a single solid colour is drawn.

        To specify a second colour for the pattern, use the high bits of any colour parameter:

            FILLP(0b0011010101101000)
            CIRCFILL(64,64,20, 0x4E) -- brown and pink

        Additional settings are given in bits 0b0.111:

            0b0.100 Transparency

                When this bit is set, the second colour is not drawn

                -- checkboard with transparent squares
                FILLP(0b0011001111001100.1) 

            0b0.010 Apply to Sprites

                When set, the fill pattern is applied to sprites (spr, sspr, map, tline), using a 
                colour mapping provided by the secondary palette.

                Each pixel value in the sprite (after applying the draw palette as usual) is taken 
                to be an index into the secondary palette. Each entry in the secondary palette 
                contains the two colours used to render the fill pattern. For example, to draw a 
                white and red (7 and 8) checkerboard pattern for only blue pixels (colour 12) in a 
                sprite:

                FOR I=0,15 DO PAL(I, I+I*16, 2) END  --  all other colours map to themselves
                PAL(12, 0x87, 2)                     --  remap colour 12 in the secondary palette
                 
                FILLP(0b0011001111001100.01)         --  checkerboard palette, applied to sprites
                SPR(1, 64,64)                        --  draw the sprite

            0b0.001 Apply Secondary Palette Globally

                When set, the secondary palette mapping is also applied by all draw functions that 
                respect fill patterns (circfill, line etc). This can be useful when used in  
                conjunction with sprite drawing functions, so that the colour index of each sprite  
                pixel means the same thing as the colour index supplied to the drawing functions.

                FILLP(0b0011001111001100.001)
                PAL(12, 0x87, 2)
                CIRCFILL(64,64,20,12)                -- red and white checkerboard circle

                The secondary palette mapping is applied after the regular draw palette mapping. So 
                the following would also draw a red and white checkered circle:

                PAL(3,12)
                CIRCFILL(64,64,20,3)

        The fill pattern can also be set by setting bits in any colour parameter:

            POKE(0x5F34, 1) -- sets integrated fillpattern + colour mode CIRCFILL(64,64,20, 
            0x114E.ABCD) -- sets fill pattern to ABCD

            -- bit  0x1000.0000 means the non-colour bits should be observed -- bit  0x0700.0000 
            0x1 transparency, 0x2 apply to sprites, 0x4 apply secondary palette  -- bits 
            0x00FF.0000 are the usual colour bits -- bits 0x0000.FFFF are interpreted as the fill 
            pattern

        The fill pattern can be applied to sprites (spr, sspr, map, tline) using bit 0b0.01

            FILLP(0b0011001111001100.011)

----------------------------------------------------------------------------------------------------
    Table Functions
----------------------------------------------------------------------------------------------------

    With the exception of PAIRS(), the following functions and the # operator apply only to tables  
    that are indexed starting from 1 and do not have NIL entries. All other forms of tables can  be 
    considered as hash maps or sets, rather than arrays that have a length.


    ADD(TBL, VAL, [INDEX])

        Add value VAL to the end of table TBL. Equivalent to:

        TBL[#TBL + 1] = VAL

        If index is given then the element is inserted at that position:

            FOO={}        -- CREATE EMPTY TABLE
            ADD(FOO, 11)
            ADD(FOO, 22)
            PRINT(FOO[2]) -- 22


    DEL(TBL, VAL)

        Delete the first instance of value VAL in table TBL. The remaining entries are shifted left 
        one index to avoid holes.

        Note that VAL is the value of the item to be deleted, not the index into the table. (To 
        remove an item at a particular index, use DELI instead). DEL returns the deleted item, or 
        returns no value when nothing was deleted.

            A={1,10,2,11,3,12}
            FOR ITEM IN ALL(A) DO
                IF (ITEM < 10) THEN DEL(A, ITEM) END
            END
            FOREACH(A, PRINT) -- 10,11,12
            PRINT(A[3])       -- 12


    DELI(TBL, [I])

        Like @DEL(), but remove the item from table TBL at index I When I is not given, the last 
        element of the table is removed and returned.


    COUNT(TBL, [VAL])

        Returns the length of table t (same as #TBL) When VAL is given, returns the number of 
        instances of VAL in that table.


    ALL(TBL)

        Used in FOR loops to iterate over all items in a table (that have a 1-based integer index),  
        in the order they were added.

            T = {11,12,13}
            ADD(T,14)
            ADD(T,"HI")
            FOR V IN ALL(T) DO PRINT(V) END -- 11 12 13 14 HI
            PRINT(#T) -- 5


    FOREACH(TBL, FUNC)

        For each item in table TBL, call function FUNC with the item as a single parameter.

            > FOREACH({1,2,3}, PRINT)


    PAIRS(TBL)

        Used in FOR loops to iterate over table TBL, providing both the key and value for each 
        item. Unlike @ALL(), PAIRS() iterates over every item regardless of indexing scheme. Order 
        is not guaranteed.

            T = {["HELLO"]=3, [10]="BLAH"}
            T.BLUE = 5;
            FOR K,V IN PAIRS(T) DO
                PRINT("K: "..K.."  V:"..V)
            END

        Output:

            K: 10  v:BLAH
            K: HELLO  v:3
            K: BLUE  v:5

----------------------------------------------------------------------------------------------------
    Input
----------------------------------------------------------------------------------------------------


    BTN([B], [PL])

        Get button B state for player PL (default 0) 

        B: 0..5: left right up down button_o button_x<br> PL: player index 0..7

        Instead of using a number for B, it is also possible to use a button glyph. (In the coded 
        editor, use Shift-L R U D O X)

        If no parameters supplied, returns a bitfield of all 12 button states for player 0 & 1 // 
        P0: bits 0..5  P1: bits 8..13

        Default keyboard mappings to player buttons:
         
            player 0: [DPAD]: cursors, [O]: Z C N   [X]: X V M
            player 1: [DPAD]: SFED,    [O]: LSHIFT  [X]: TAB W  Q A

        Although PICO-8 accepts all button combinations, note that it is generally impossible to 
        press both LEFT and RIGHT at the same time on a physical game controller. On some 
        controllers, UP + LEFT/RIGHT is also awkward if [X] or [O] could be used instead of UP 
        (e.g. to jump / accelerate).


    BTNP(B, [PL])

        BTNP is short for "Button Pressed"; Instead of being true when a button is held down,  BTNP 
        returns true when a button is down AND it was not down the last frame. It also repeats 
        after 15 frames, returning true every 4 frames after that (at 30fps -- double that at 
        60fps). This can be used for things like menu navigation or grid-wise player  movement.

        The state that BTNP reads is reset at the start of each call to @_UPDATE or @_UPDATE60, so 
        it is preferable to use BTNP from inside one of those functions.

        Custom delays (in frames @ 30fps) can be set by poking the following memory addresses:

        POKE(0X5F5C, DELAY) -- SET THE INITIAL DELAY BEFORE REPEATING. 255 MEANS NEVER REPEAT.
        POKE(0X5F5D, DELAY) -- SET THE REPEATING DELAY.

        In both cases, 0 can be used for the default behaviour (delays 15 and 4)

----------------------------------------------------------------------------------------------------
    Audio
----------------------------------------------------------------------------------------------------


    SFX(N, [CHANNEL], [OFFSET], [LENGTH])

        Play sfx N (0..63) on CHANNEL (0..3) from note OFFSET (0..31 in notes) for LENGTH notes.

        Using negative CHANNEL values have special meanings:

        CHANNEL -1: (default) to automatically choose a channel that is not being used
        CHANNEL -2: to stop the given sound from playing on any channel

        N can be a command for the given CHANNEL (or all channels when CHANNEL < 0):

        N -1: to stop sound on that channel
        N -2: to release sound on that channel from looping

        SFX(3)    --  PLAY SFX 3
        SFX(3,2)  --  PLAY SFX 3 ON CHANNEL 2
        SFX(3,-2) --  STOP SFX 3 FROM PLAYING ON ANY CHANNEL
        SFX(-1,2) --  STOP WHATEVER IS PLAYING ON CHANNEL 2
        SFX(-2,2) --  RELEASE LOOPING ON CHANNEL 2
        SFX(-1)   --  STOP ALL SOUNDS ON ALL CHANNELS
        SFX(-2)   --  RELEASE LOOPING ON ALL CHANNELS


    MUSIC(N, [FADE_LEN], [CHANNEL_MASK])

        Play music starting from pattern N (0..63)
        N -1 to stop music
         
        FADE_LEN is in ms (default: 0). So to fade pattern 0 in over 1 second:

        MUSIC(0, 1000)

        CHANNEL_MASK specifies which channels to reserve for music only. For example, to play only 
        on channels 0..2:

        MUSIC(0, NIL, 7) -- 1 | 2 | 4

        Reserved channels can still be used to play sound effects on, but only when that channel 
        index is explicitly requested by @SFX().

----------------------------------------------------------------------------------------------------
    Map
----------------------------------------------------------------------------------------------------

    The PICO-8 map is a 128x32 grid of 8-bit cells, or 128x64 when using the shared memory. When  
    using the map editor, the meaning of each cell is taken to be an index into the sprite sheet  
    (0..255). However, it can instead be used as a general block of data.


    MGET(X, Y)

    MSET(X, Y, VAL)

        Get or set map value (VAL) at X,Y

        When X,Y is outside of the map range, MSET returns 0.


    MAP([CELL_X], CELL_Y, [SX, SY], [CELL_W, CELL_H], [LAYERS])

        Draw section of map (starting from CELL_X, CELL_Y) at screen position SX, SY (pixels).

        To draw a 4x2 blocks of cells starting from 0,0 in the map, to the screen at 20,20:

        MAP(0, 0, 20, 20, 4, 2) 

        CELL_W and CELL_H default to 128,32 (the top half of the map). To draw the whole map, 
        including the bottom half shared with the sprite sheet, use:

        MAP(0, 0, 0, 0, 128, 64)

        MAP() is often used in conjunction with CAMERA(). To draw the map so that a player object 
        (at PL.X in PL.Y in pixels) is centered:

        CAMERA(PL.X - 64, PL.Y - 64
        MAP()

        LAYERS is a bitfield. When given, only sprites with matching sprite flags are drawn. For 
        example, when LAYERS is 0x5, only sprites with flag 0 and 2 are drawn.

        Sprite 0 is taken to mean "empty" and is not drawn. To disable this behaviour, use: 
        POKE(0x5F36, 0x8)


    TLINE(X0, Y0, X1, Y1, MX, MY, [MDX, MDY], [LAYERS])

        Draw a textured line from (X0,Y0) to (X1,Y1), sampling colour values from the map. When 
        LAYERS is specified, only sprites with matching flags are drawn (similar to MAP()) 

        MX, MY are map coordinates to sample from, given in tiles. Colour values are sampled from 
        the 8x8 sprite present at each map tile. For example:

            2.0, 1.0  means the top left corner of the sprite at position 2,1 on the map
            2.5, 1.5  means pixel (4,4) of the same sprite

        MDX, MDY are deltas added to mx, my after each pixel is drawn. (Defaults to 0.125, 0)

        The map coordinates (MX, MY) are masked by values calculated by subtracting 0x0.0001 from 
        the values at address 0x5F38 and 0x5F39. In simpler terms, this means you can loop a 
        section of the map by poking the width and height you want to loop within, as  long as they 
        are powers of 2 (2,4,8,16..)

        For example, to loop every 8 tiles horizontally, and every 4 tiles vertically:

            POKE(0x5F38, 8)
            POKE(0x5F39, 4)
            TLINE(...)

        The default values (0,0) gives a masks of 0xff.ffff, which means that the samples will loop 
        every 256 tiles.

        An offset to sample from (also in tiles) can also be specified at addresses 0x5f3a, 0x5f3b:

            POKE(0x5F3A, OFFSET_X)
            POKE(0x5F3B, OFFSET_Y)

        Sprite 0 is taken to mean "empty" and not drawn. To disable this behaviour, use: 
        POKE(0x5F36, 0x8)

----------------------------------------------------------------------------------------------------
    Memory
----------------------------------------------------------------------------------------------------

    PICO-8 has 3 types of memory:

        1. Base RAM (64k): see layout below. Access with PEEK() POKE() MEMCPY() MEMSET()
        2. Cart ROM (32k): same layout as base ram until 0x4300
        3. Lua RAM (2MB): compiled program + variables

        Technical note: While using the editor, the data being modified is in cart rom, but api 
        functions such as @SPR()  and @SFX() only operate on base ram. PICO-8 automatically copies 
        cart rom to base ram (i.e. calls @RELOAD()) in 3 cases:<br> 1. When a cartridge is 
        loaded<br> 2. When a cartridge is run<br> 3. When exiting any of the editor modes // can 
        turn off with: poke(0x5f37,1)<br>

    :: Base RAM Memory Layout

        0X0    GFX
        0X1000 GFX2/MAP2 (SHARED)
        0X2000 MAP
        0X3000 GFX FLAGS
        0X3100 SONG
        0X3200 SFX
        0X4300 USER DATA
        0X5600 CUSTOM FONT (IF ONE IS DEFINED)
        0X5E00 PERSISTENT CART DATA (256 BYTES)
        0X5F00 DRAW STATE
        0X5F40 HARDWARE STATE
        0X5F80 GPIO PINS (128 BYTES)
        0X6000 SCREEN (8K)
        0x8000 USER DATA

        User data has no particular meaning and can be used for anything via @MEMCPY(), @PEEK() & 
        @POKE(). Persistent cart data is mapped to 0x5e00..0x5eff but only stored if @CARTDATA() 
        has been called. Colour format (gfx/screen) is 2 pixels per byte: low bits encode the left 
        pixel of each pair. Map format is one byte per cel, where each byte normally encodes a 
        sprite index.

    :: Remapping Graphics and Map Data

        The GFX, MAP and SCREEN memory areas can be reassigned by setting values at the following 
        addresses:

        0X5F54 GFX:    can be 0x00 (default) or 0x60 (use the screen memory as the spritesheet)
        0X5F55 SCREEN: can be 0x60 (default) or 0x00 (use the spritesheet as screen memory)
        0X5F56 MAP:    can be 0x20 (default) or 0x10..0x2f, or 0x80 and above.
        0X5F57 MAP SIZE: map width. 0 means 256. Defaults to 128.

        Addresses can be expressed in 256 byte increments. So 0x20 means 0x2000, 0x21 means 0x2100 
        etc. Map addresses 0x30..0x3f are taken to mean 0x10..0x1f (shared memory area) Map data 
        can only be contained inside the memory regions 0x1000..0x2fff, 0x8000..0xffff, and  the 
        map height is determined to be the largest possible size that fits in the given region.


    PEEK(ADDR, [N])

        Read a byte from an address in base ram. If N is specified, PEEK() returns that number of 
        results (max: 8192). For example, to read the first 2 bytes of video memory:

            A, B = PEEK(0x6000, 2)


    POKE(ADDR, VAL1, VAL2, ...)

        Write one or more bytes to an address in base ram. If more than one parameter is provided, 
        they are written sequentially (max: 8192).


    PEEK2(ADDR)

    POKE2(ADDR, VAL)

    PEEK4(ADDR)

    POKE4(ADDR, VAL)

        16-bit and 32-bit versions of PEEK and POKE. Read and write one number (VAL) in 
        little-endian format:

            16 bit: 0xffff.0000
            32 bit: 0xffff.ffff

        ADDR does not need to be aligned to 2 or 4-byte boundaries.

    Alternatively, the following operators can be used to peek (but not poke), and are slightly 
    faster:

        @ADDR  -- PEEK(ADDR)
        %ADDR  -- PEEK2(ADDR)
        $ADDR  -- PEEK4(ADDR)


    MEMCPY(DEST_ADDR, SOURCE_ADDR, LEN)

        Copy LEN bytes of base ram from source to dest. Sections can be overlapping


    RELOAD(DEST_ADDR, SOURCE_ADDR LEN, [FILENAME])

        Same as MEMCPY, but copies from cart rom.

        The code section ( >= 0x4300) is protected and can not be read.

        If filename specified, load data from a separate cartridge. In this case, the cartridge 
        must be local (BBS carts can not be read in this way).


    CSTORE(DEST_ADDR, SOURCE_ADDR, LEN, [FILENAME])

        Same as memcpy, but copies from base ram to cart rom.

        CSTORE() is equivalent to CSTORE(0, 0, 0x4300)

        The code section ( >= 0x4300) is protected and can not be written to.

        If FILENAME is specified, the data is written directly to that cartridge on disk. Up to 64 
        cartridges can be written in one session. See @{Cartridge Data} for more information.


    MEMSET(DEST_ADDR, VAL, LEN)

        Write the 8-bit value VAL into memory starting at DEST_ADDR, for LEN bytes.

        For example, to fill half of video memory with 0xC8:

        > MEMSET(0x6000, 0xC8, 0x1000)

----------------------------------------------------------------------------------------------------
    Math
----------------------------------------------------------------------------------------------------


    MAX(X, Y)

    MIN(X, Y)

    MID(X, Y, Z)

        Returns the maximum, minimum, or middle value of parameters

        > ?MID(7,5,10) -- 7


    FLR(X)

        > ?FLR ( 4.1) -->  4		
        > ?FLR (-2.3) --> -3


    CEIL(X)

        Returns the closest integer that is equal to or below x

        > ?CEIL( 4.1) -->  5
        > ?CEIL(-2.3) --> -2


    COS(X)

    SIN(X)

        Returns the cosine or sine of x, where 1.0 means a full turn. For example, to animate a 
        dial that turns once every second:

        FUNCTION _DRAW()
            CLS()
            CIRC(64, 64, 20, 7)
            X = 64 + COS(T()) * 20
            Y = 64 + SIN(T()) * 20
            LINE(64, 64, X, Y)	
        END

        PICO-8's SIN() returns an inverted result to suit screenspace (where Y means "DOWN", as 
        opposed  to mathematical diagrams where Y typically means "UP").

        > SIN(0.25) -- RETURNS -1

        To get conventional radian-based trig functions without the y inversion,  paste the 
        following snippet near the start of your program:

        P8COS = COS FUNCTION COS(ANGLE) RETURN P8COS(ANGLE/(3.1415*2)) END
        P8SIN = SIN FUNCTION SIN(ANGLE) RETURN -P8SIN(ANGLE/(3.1415*2)) END


    ATAN2(DX, DY)

        Converts DX, DY into an angle from 0..1

        As with cos/sin, angle is taken to run anticlockwise in screenspace. For example:

            > ?ATAN(0, -1) -- RETURNS 0.25

        ATAN2 can be used to find the direction between two points:

            X=20 Y=30
            FUNCTION _UPDATE()
                IF (BTN(0)) X-=2
                IF (BTN(1)) X+=2
                IF (BTN(2)) Y-=2
                IF (BTN(3)) Y+=2	
            END
             
            FUNCTION _DRAW()
                CLS()
                CIRCFILL(X,Y,2,14)
                CIRCFILL(64,64,2,7)
                 
                A=ATAN2(X-64, Y-64)
                PRINT("ANGLE: "..A)
                LINE(64,64,
                    64+COS(A)*10,
                    64+SIN(A)*10,7)
            END


    SQRT(X)

        Return the square root of x


    ABS(X)

        Returns the absolute (positive) value of x


    RND(X)

        Returns a random number n, where 0 <= n < x

        If you want an integer, use flr(rnd(x)). If x is an array-style table, return a random 
        element between table[1] and table[#table].


    SRAND(X)

        Sets the random number seed. The seed is automatically randomized on cart startup.

        FUNCTION _DRAW()
            CLS()
            SRAND(33)
            FOR I=1,100 DO
                PSET(RND(128),RND(128),7)
            END
        END

    :: Bitwise Operations

        Bitwise operations are similar to logical expressions, except that they work at the bit 
        level.

        Say you have two numbers (written here in binary using the "0b" prefix): 

            X = 0b1010
            Y = 0b0110

        A bitwise AND will give you bits set when the corresponding bits in X /and/ Y are both set

        > PRINT(BAND(X,Y)) -- RESULT:0B0010 (2 IN DECIMAL)

        There are 9 bitwise functions available in PICO-8:

            BAND(X, Y) -- BOTH BITS ARE SET
            BOR(X, Y)  -- EITHER BIT IS SET
            BXOR(X, Y) -- EITHER BIT IS SET, BUT NOT BOTH OF THEM
            BNOT(X)    -- EACH BIT IS NOT SET
            SHL(X, N)  -- SHIFT LEFT N BITS (ZEROS COME IN FROM THE RIGHT)
            SHR(X, N)  -- ARITHMETIC RIGHT SHIFT (THE LEFT-MOST BIT STATE IS DUPLICATED)
            LSHR(X, N) -- LOGICAL RIGHT SHIFT (ZEROS COMES IN FROM THE LEFT)
            ROTL(X, N) -- ROTATE ALL BITS IN X LEFT BY N PLACES
            ROTR(X, N) -- ROTATE ALL BITS IN X RIGHT BY N PLACES

        Operator versions are also available: & | ^^ ~ << >> >>> <<> >><

        For example: PRINT(67 & 63) -- result:3  equivalent to BAND(67,63)

        Operators are slightly faster than their corresponding functions. They behave exactly the 
        same, except that if any operands are not numbers the result is a runtime error (the 
        function versions instead default to a value of 0).

    :: Integer Division

        Integer division can be performed with a \

        > PRINT(9\2) -- RESULT:4  EQUIVALENT TO FLR(9/2)

----------------------------------------------------------------------------------------------------
    Custom Menu Items
----------------------------------------------------------------------------------------------------


    MENUITEM(INDEX, [LABEL], [CALLBACK])

        Add an extra item to the pause menu

        Index should be 1..5 and determines the order each menu item is displayed label should be a 
        string up to 16 characters long callback is a function called when the item is selected by 
        the users

        When no label or function is supplied, the menu item is removed

        MENUITEM(1, "RESTART PUZZLE",
            FUNCTION() RESET_PUZZLE() SFX(10) END
        )

        If the callback returns true, the pause menu remains open. The callback takes a single 
        parameter that is a bitfield of L,R,X button presses

        MENUITEM(1, "FOO", 
            FUNCTION(B) IF (B&1 > 0) THEN PRINTH("LEFT WAS PRESSED") END END
        )

----------------------------------------------------------------------------------------------------
    Strings and Type Conversion
----------------------------------------------------------------------------------------------------

    Strings in Lua are written either in single or double quotes or with matching [[ ]] brackets:

        S = "THE QUICK"
        S = 'BROWN FOX';
        S = [[
            JUMPS OVER
            MULTIPLE LINES
        ]]

    The length of a string (number of characters) can be retrieved using the # operator:

        >PRINT(#S)

    Strings can be joined using the .. operator. Joining numbers converts them to strings.

        >PRINT("THREE "..4) --> "THREE 4"

    When used as part of an arithmetic expression, string values are converted to numbers:

        >PRINT(2+"3")   --> 5


    TOSTR(VAL, [FORMAT_FLAGS])

        Convert VAL to a string.

        FORMAT_FLAGS is a bitfield:

            0x1: Write the raw hexadecimal value of numbers, functions or tables.
            0x2: Write VAL as a signed 32-bit integer by shifting it left by 16 bits.

        TOSTR(NIL) returns "[nil]"

        TOSTR() returns ""

        TOSTR(17)       -- "17"
        TOSTR(17,0x1)   -- "0x0011.0000"
        TOSTR(17,0x3)   -- "0x00110000"
        TOSTR(17,0x2)   -- "1114112"


    TONUM(VAL, [FORMAT_FLAGS])

        Converts VAL to a number.

        TONUM("17.5")  -- 17.5
        TONUM(17.5)    -- 17.5
        TONUM("HOGE")  -- NO RETURN VALUE

        FORMAT_FLAGS is a bitfield:

            0x1: Read the string as written in (unsigned, integer) hexadecimal without the "0x" prefix
                 Non-hexadecimal characters are taken to be '0'.
            0x2: Read the string as a signed 32-bit integer, and shift right 16 bits.
            0x4: When VAL can not be converted to a number, return 0

        TONUM("FF",       0x1)  -- 255
        TONUM("1114112",  0x2)  -- 17
        TONUM("1234abcd", 0x3)  -- 0x1234.abcd


    CHR(VAL0, VAL1, ...)

        Convert one or more ordinal character codes to a string.

        When 

        CHR(64)                    -- "@"
        CHR(104,101,108,108,111)   -- "@"


    ORD(STR, [INDEX], [NUM_RESULTS])

        Convert one or more characters from string STR to their ordinal (0..255) character codes.

        Use the INDEX parameter to specify which character in the string to use. When INDEX is out 
        of range or str is not a string, ORD returns nil.

        When NUM_RESULTS is given, ORD returns multiple values starting from INDEX.

        ORD("@")         -- 64
        ORD("123",2)     -- 50 (THE SECOND CHARACTER: "2")
        ORD("123",2,3)   -- 50,51,52


    SUB(STR, POS0, [POS1])

        Grab a substring from string str, from pos0 up to and including pos1. When POS1 is not 
        specified, the remainder of the string is returned. When POS1 is specified, but not a 
        number, a single character at POS0 is returned.

        S = "THE QUICK BROWN FOX"
        PRINT(SUB(S,5,9))   --> "QUICK"
        PRINT(SUB(S,5))     --> "QUICK BROWN FOX"
        PRINT(SUB(S,5,_))   --> "Q"


    SPLIT(STR, [SEPARATOR], [CONVERT_NUMBERS])

        Split a string into a table of elements delimited by the given separator (defaults to ","). 
        When separator is a number n, the string is split into n-character groups. When 
        convert_numbers is true, numerical tokens are stored as numbers (defaults to true). Empty 
        elements are stored as empty strings.

        SPLIT("1,2,3")               -- {1,2,3}
        SPLIT("ONE:TWO:3",":",FALSE) -- {"ONE","TWO","3"}
        SPLIT("1,,2,")               -- {1,"",2,""}


    TYPE(VAL)

        Returns the type of val as a string.

        > PRINT(TYPE(3))
        NUMBER
        > PRINT(TYPE("3"))
        STRING

----------------------------------------------------------------------------------------------------
    Cartridge Data
----------------------------------------------------------------------------------------------------

    Using @CARTDATA(), @DSET(), AND @DGET(), 64 numbers (256 bytes) of persistent data  can be 
    stored on the user's PICO-8 that persists after the cart is unloaded or PICO-8 is shutdown. 
    This can be used as a lightweight way to store things like  high scores or to save player 
    progress. It can also be used to share data across  cartridges / cartridge versions.

    If more than 256 bytes is needed, it is also possible to write directly to the cartridge using 
    @CSTORE(). The disadvantage is that the data is tied to that particular version of the 
    cartridge. e.g. if a game is updated, players will lose their savegames. Also, some space in 
    the data sections of the cartridge need to be left available to use as storage.

    Another alternative is to write directly to a second cartridge by specifying a fourth parameter 
    to @CSTORE(). This requires a cart swap (which in reality only means the user needs to watch a 
    spinny cart animation for 1 second).

        CSTORE(0,0,0X2000, "SPRITE SHEET.P8")
        -- LATER, RESTORE THE SAVED DATA:
        RELOAD(0,0,0X2000, "SPRITE SHEET.P8")


    CARTDATA(ID)

        Opens a permanent data storage slot indexed by ID that can be used to store and retrieve up 
        to 256 bytes (64 numbers) worth of data using @DSET() and @DGET().

            CARTDATA("ZEP_DARK_FOREST")
            DSET(0, SCORE)

        ID is a string up to 64 characters long, and should be unusual enough that  other 
        cartridges do not accidentally use the same id. Legal characters are a..z, 0..9 and 
        underscore (_)

        Returns true if data was loaded, otherwise false.

        CARTDATA can be called once per cartridge execution, and so only a single data slot can be 
        used.

        Once a cartdata ID has been set, the area of memory 0X5E00..0X5EFF is mapped  to permanent 
        storage, and can either be accessed directly or via @DGET()/@DSET().

        There is no need to flush written data -- it is automatically saved to permanent storage 
        even if modified by directly @POKE()'ing 0X5E00..0X5EFF.


    DGET(INDEX)

        Get the number stored at INDEX (0..63)

        Use this only after you have called @CARTDATA()


    DSET(INDEX, VALUE)

        Set the number stored at index (0..63)

        Use this only after you have called @CARTDATA()

----------------------------------------------------------------------------------------------------
    GPIO
----------------------------------------------------------------------------------------------------

    GPIO stands for "General Purpose Input Output", and allows machines to communicate with  each 
    other. PICO-8 maps bytes in the range 0x5f80..0x5fff to gpio pins that can be


    POKE()ed (to output a value -- e.g. to make an LED light up) or @PEEK()ed (e.g. to read

    the state of a switch).

    GPIO means different things for different host platforms:

    CHIP:         0x5f80..0x5f87 mapped to xio-p0..xio-p7
    Pocket CHIP:  0x5f82..0x5f87 mapped to GPIO1..GPIO6
        // xio-p0 & p1 are exposed inside the prototyping area inside the case.
    Raspberry Pi: 0x5f80..0x5f9f mapped to wiringPi pins 0..31
        // see http://wiringpi.com/pins/ for mappings on different models.
        // also: watch out for BCM vs. WiringPi GPIO indexing!

    CHIP and Raspberry Pi values are all digital: 0 (LOW) and 255 (HIGH)

    A program to blink any LEDs attached on and off:

        T = 0
        FUNCTION _DRAW()
         CLS(5)
         FOR I=0,7 DO
          VAL = 0
          IF (T % 2 < 1) VAL = 255
          POKE(0X5F80 + I, VAL)
          CIRCFILL(20+I*12,64,4,VAL/11)
         END
         T += 0.1
        END

    :: Serial

        For more precise timing, the @SERIAL() command can be used. GPIO writes are buffered and  
        dispatched at the end of each frame, allowing clock cycling at higher and/or more regular  
        speeds than is possible by manually bit-banging using @POKE() calls.


        SERIAL(CHANNEL, ADDRESS, LENGTH)

            CHANNEL:
                0x000..0x0fe    corresponds to gpio pin numbers; send 0x00 for LOW or 0xFF for HIGH
                0x0ff           delay; length is taken to mean "duration" in microseconds (excl. overhead)
                0x400..0x401    ws281x LED string (experimental)

            ADDRESS: The PICO-8 memory location to read from / write to.

            LENGTH:  Number of bytes to send. 1/8ths are allowed to send partial bit strings.

        For example, to send a byte one bit at a time to a typical APA102 LED string:

            VAL = 42          -- VALUE TO SEND
            DAT = 16 CLK = 15 -- DATA AND CLOCK PINS DEPEND ON DEVICE
            POKE(0X4300,0)    -- DATA TO SEND (SINGLE BYTES: 0 OR 0XFF)
            POKE(0X4301,0XFF)
            FOR B=0,7 DO
                -- SEND THE BIT (HIGH FIRST)
                SERIAL(DAT, BAND(VAL, SHL(1,7-B))>0 AND 0X4301 OR 0X4300, 1)
                -- CYCLE THE CLOCK
                SERIAL(CLK, 0X4301)
                SERIAL(0XFF, 5) -- DELAY 5
                SERIAL(CLK, 0X4300)
                SERIAL(0XFF, 5) -- DELAY 5
            END

        Additional channels are available for bytestreams to and from the host operating system. 
        These are intended to be most useful for UNIX-like environments while developing 
        toolchains, and are not available while running a BBS or exported cart [1]. Maximum 
        transfer rate in all  cases is 64k/sec (blocks cpu).

                0x800  dropped file   //  stat(120) returns TRUE when data is available
                0x802  dropped image  //  stat(121) returns TRUE when data is available
                0x804  stdin
                0x805  stdout
                0x806  file specified with: pico8 -i filename
                0x807  file specified with: pico8 -o filename

        Image files dropped into PICO-8 show up on channel 0x802 as a bytestream with a special 
        format: The first 4 bytes are the image's width and height (2 bytes each little-endian, 
        like PEEK2), followed by the image in reading order, one byte per pixel, colour-fitted to 
        the display palette at the time the file was dropped.

        [1]	Channels 0x800 and 0x802 are available from exported binaries, but with a maximum file 
        size of 256k, or 128x128 for images.

    :: HTML

        Cartridges exported as HTML / .js use a global array of integers (pico8_gpio) to  represent 
        gpio pins. The shell HTML should define the array:

        var pico8_gpio = Array(128);

----------------------------------------------------------------------------------------------------
    Mouse and Keyboard Input
----------------------------------------------------------------------------------------------------

    // EXPERIMENTAL -- but mostly working on all platforms

    Mouse and keyboard input can be achieved by enabling devkit input mode:

    POKE(0x5F2D, flags)  -- where flags are:

        0x1 Enable
        0x2 Mouse buttons trigger btn(4)..btn(6)
        0x4 Pointer lock (use stat 38..39 to read movements)

    Note that not every PICO-8 will have a keyboard or mouse attached to it, so when posting carts 
    to the Lexaloffle BBS, it is encouraged to make keyboard and/or mouse control  optional and off 
    by default, if possible. When devkit input mode is enabled, a message is displayed to BBS users 
    warning them that the program may be expecting input beyond the  standard 6-button controllers.

    The state of the mouse and keyboard can be found in stat(x):

        STAT(30) -- (Boolean) True when a keypress is available
        STAT(31) -- (String) character returned by keyboard
        STAT(32) -- Mouse X
        STAT(33) -- Mouse Y
        STAT(34) -- Mouse buttons (bitfield)
        STAT(36) -- Mouse wheel event
        STAT(38) -- Relative x movement (in host desktop pixels) -- requires flag 0x4
        STAT(39) -- Relative y movement (in host desktop pixels) -- requires flag 0x4

----------------------------------------------------------------------------------------------------
    Additional Lua Features
----------------------------------------------------------------------------------------------------

PICO-8 also exposes 2 features of Lua for advanced users: Metatables and Coroutines.

For more information, please refer to the Lua 5.2 manual.

:: Metatables

    Metatables can be used to define the behaviour of objects under particular operations. For 
    example, to use tables to represent 2D vectors that can be added together, the  '+' operator is 
    redefined by defining an "__add" function for the metatable:

        VEC2D={
         __ADD=FUNCTION(A,B) 
         	RETURN {X=(A.X+B.X), Y=(A.Y+B.Y)} 
         END
        }
         
        V1={X=2,Y=9} SETMETATABLE(V1, VEC2D)
        V2={X=1,Y=5} SETMETATABLE(V2, VEC2D)
        V3 = V1+V2
        PRINT(V3.X..","..V3.Y) -- 3,14


    SETMETATABLE(TBL, M)

        Set table TBL metatable to M


    GETMETATABLE(TBL)

        return the current metatable for table t, or nil if none is set


    RAWSET(TBL, KEY, VALUE)

    RAWGET(TBL, KEY)

    RAWEQUAL(TBL1,TBL2

    RAWLEN(TBL)

        Raw access to the table, as if no metamethods were defined.

:: Function Arguments

    The list of function arguments can be specifed with ... 

        FUNCTION PREPRINT(PRE, S, ...)
            LOCAL S2 = PRE..TOSTR(S)
            PRINT(S2, ...) -- PASS THE REMAINING ARGUMENTS ON TO PRINT()
        END

    To accept a variable number of arguments, use them to define a table and/or use Lua's select() 
    function. select(index, ...) returns all of the arguments after index.

        FUNCTION FOO(...)
            LOCAL ARGS={...} -- BECOMES A TABLE OF ARGUMENTS
            FOREACH(ARGS, PRINT)
            ?SELECT("#",...)    -- ALTERNATIVE WAY TO COUNT THE NUMBER OF ARGUMENTS
            FOO2(SELECT(3,...)) -- PASS ARGUMENTS FROM 3 ONWARDS TO FOO2()
        END

:: Coroutines

    Coroutines offer a way to run different parts of a program in a somewhat concurrent  way, 
    similar to threads. A function can be called as a coroutine, suspended with 


    YIELD() any number of times, and then resumed again at the same points.

        FUNCTION HEY()
            PRINT("DOING SOMETHING")
            YIELD()
            PRINT("DOING THE NEXT THING")
            YIELD()
            PRINT("FINISHED")
        END
         
        C = COCREATE(HEY)
        FOR I=1,3 DO CORESUME(C) END


    COCREATE(F)

        Create a coroutine for function f.


    CORESUME(C, [P0, P1 ..])

        Run or continue the coroutine c. Parameters p0, p1.. are passed to the coroutine's 
        function.

        Returns true if the coroutine completes without any errors Returns false, error_message if 
        there is an error.

        ** Runtime errors that occur inside coroutines do not cause the program to stop running. It 
        is a good idea to wrap CORESUME() inside an @ASSERT(). If the assert fails, it will print 
        the error message generated by  coresume.


        ASSERT(CORESUME(C))


    COSTATUS(C)

        Return the status of coroutine C as a string:
            "running"
            "suspended"
            "dead"


    YIELD

        Suspend execution and return to the caller.

====================================================================================================
    Appendix
====================================================================================================

----------------------------------------------------------------------------------------------------
    Appendix A: P8SCII Control Codes
----------------------------------------------------------------------------------------------------

    When printed with @PRINT(), some characters have a special meaning that can be used to alter 
    things like the cursor position and text rendering style. Control characters in PICO-8 are 
    CHR(0)..CHR(15) and can be written as an escaped sequence ("\n" for newline etc.)

    Some of the control codes below take parameters which are written using a scheme that is a 
    superset of hexadecimal format. That is, '0'..'f' also mean 0..15. But characters after 'f' are 
    also accepted: 'g' means 16 and so on. Such parameters are written below as P0, P1.

    For example, to print with a blue background ("\#c") and dark gray foreground ("\f5"):

        PRINT("\#C\F5 BLUE ")

    The only side-effects on the draw state are changes in cursor position and foreground color; 
    all other attributes are reset each time @PRINT() is called.

    :: Control Codes

        0 "\0"   terminate printing
        1 "\*"   repeat next character P0 times. ?"\*3a" --> aaa
        2 "\#"   draw solid background with colour P0 
        3 "\-"   shift cursor horizontally by P0-16 pixels
        4 "\|"   shift cursor vertically by P0-16 pixels
        5 "\+"   shift cursor by P0-16, P1-16 pixels
        6 "\^"   special command (see below)
        7 "\a"   audio (see below)
        8 "\b"   backspace
        9 "\t"   tab
        a "\n"   newline
        b "\v"   decorate previous character (see below)
        c "\f"   set foreground colour
        d "\r"   carriage return
        e "\014" switch to font defined at 0x5600
        f "\015" switch to default font

    :: Special Commands

        These commands all start with "\^" and take up to 2 parameters (P0, P1) For example, to 
        clear screen to dark blue: print("\^c1")

            1..9 skip 1,2,4,8,16,32..256 frames		
            c cls to colour P0, set cursor to 0,0
            d set delay to P0 frames for every character printed
            g set cursor position to home
            h set home to cursor position
            j jump to absolute P0*4, P1*4 (in screen pixels)
            r set rhs character wrap boundary to P0*4
            s set tab stop width to P0 pixels (used by "\t")
            x set character width  (default: 4)
            y set character height (default: 6)

        :: Rendering mode options  

            // prefix these with "-" to disable: e.g. ?"\^i on \^-i off "

            w wide mode: scales by 2x1 
            t tall mode: scales by 1x2
            = stripey mode: when wide or tall, draw only even pixels
            p pinball mode: equivalent to setting wide, tall and stripey
            i invert
            b border: toggle 1px padding on left and top // on by default
            # solid background  // off by default, but enabled automatically by \#

        :: Raw memory writes

            The following two commands take 4-character hex parameters:

            @addrnnnn[binstr] poke nnnn bytes to address addr
            !addr[binstr]     poke all remaining characters to address addr

            For example, to write 4 bytes to video memory halfway down the screen:

            >?"\^@70000004xxxxhello"

        :: One-off characters

            Character data can be specified and printed in-line using \^. followed by 8 bytes of 
            raw binary data, or \^: followed by 8 2-digit hexadecimal values. The data format is 
            the same as custom fonts; each byte specifies a row of 1-bit pixel values, with the  
            low bit on the left.

            \^.[8 chars of raw binary data]
            \^:[16 chars of hexadecimal]

            To print a cat:

            > ?"\^:447cb67c3e7f0106"

    :: Audio 

        ? ?"\A"   -- SINGLE BEEP ?"\A12" -- PLAY EXISTING DATA AT SFX 12

        If an sfx index is not specified, a non-active sfx between 60..63 is selected 
        automatically. To fill the SFX with data before playback, the following commands can then 
        be appended.

        1. (optional) SFX attributes must appear once at the start as they apply to the whole 
        sound:

            s P0     set the sfx speed
            l P0 P1  set the sfx loop start and end points

        2. Note data:

            Note are written as a..g, optionally followed by a sharp # or flat -, and octave 
            number.

                PRINT "\ACE-G" -- MINOR TRIAD

            Empty notes Can be written with a dot:

                PRINT "\AC..E-..G" -- STACCATO MINOR TRIAD 

            Note attribute commands apply to following notes:

            i P0    set the instrument (default: 5)
            v P0    set the volume     (default: 5)
            x P0    set the effect     (default: 0)

            For example, to play a fast (speed 4), staccato (effect 5) arpeggio starting at C1:

                PRINT "\AS4X5C1EGC2EGC3EGC4"

    :: Decoration Characters

        The control character \v can be used to decorate the last printed character with another 
        character at a given offset, without needing to otherwise manage the cursor position. After 
        the decorating character is printed, the previous cursor position is restored.

        The format is \v P0 char, where P0 is a number giving the desired offset, and char is any 
        character to print at that offset (relative to the previous printed character).

        The offset has x packed into the lowest 2 bits, and starts (-2,-8) in reading order. So 3 
        means (+1, -8), 4 means (-2, -7) and so on.

        For example, to write "café!", using a comma to draw the acute accent:

            PRINT"\NCAFE\VB,!"

        In this case P0 is 'b', which is read as the number 11. So the comma is drawn at:

            x = (11%4)-2 = 1
            y = (11\4)-8 = -6

    :: Custom Font

        A custom font can be defined at 0x5600, consisting of 8 bytes per character * 256 
        characters = 2048 bytes. Each character is an 8x8 bitfield (1 bit/pixel), where starting 
        from the top, each row is a single byte starting with 0x1 on the left.

        The first five bytes (character 0 is never drawn) describes attributes of the font:

            0x5600 character width in pixels (can be more than 8, but only 8 pixels are drawn)
            0x5601 character width for character 128 and above
            0x5602 character height in pixels
            0x5603 draw offset x
            0x5604 draw offset y

    :: Default Attributes

        Although attributes are reset every time @PRINT() is called, it is possible to set their 
        default values by writing to memory addresses 0x5f58..0x5f5b.

        0x5f58 // bitfield
            0x1  when set to 0x1, bits 1..7 are observed:
            0x2  padding
            0x4  wide
            0x8  tall
            0x10 solid background
            0x20 invert
            0x40 stripey (when wide or tall)
            0x80 use custom font
         
            // e.g. poke(0x5f58, 0x1 | 0x2 | 0x4 | 0x8 | 0x20 | 0x40)  -- pinball everywhere
        0x5f59 char_w   (low nibble), char_h   (high)
        0x5f5a char_w2  (low nibble), tab_w    (high)
        0x5f5b offset_x (low nibble), offset_y (high)

        // any nibbles equal to 0 are ignored // tab_w values are mapped to 4..64



--------------------------------------------------------------------------------------------
	PICO-8 VERSION HISTORY
--------------------------------------------------------------------------------------------

	v0.2.4b

		Added: l in sprite sheet navigator to set loop start / end points (then q,w or a,z to navigate)
		Added: ctrl-b in gfx editor to paste 2x2 original size ("paste big")
		Added: DEL / backspace to clear selected region in gfx / map editors, and ctrl-x to cut
		Added: aggressive_backups option in config.txt (off by default)
		Added: transform_screen in config.txt to globally rotate / flip the video output
		Added: stat(57) (boolean) true when music triggered by music() is playing or about to start
		Changed: memset() faster than using peek4/poke4; now 2 cycles per byte at 8MHz (was 4)
		Changed: "running at < 30fps" warning on boot now only for raspi builds, and w/ higher tolerance
		Changed: Controller inputs are accepted even when PICO-8 is not the foreground application
		Changed: Map can be located at 0x1000 .. 0x2f00 using poke(0x5f56, 0x11) .. poke(0x5f56,0x2f)
		Changed: Dotty text mode is now "\^=" ("Stripey") instead of "\^." // #gunayawuho #klax #impossible
		Fixed: (not confirmed) crash causing 0-byte .p8 when audio mixer is called during save / run
		Fixed: preprocessor not counting comments as white space; should allow: ".. end--[[]]if .."
		Fixed: pal(nil) behaving the same way as pal(0); should be same as pal() // broke #rtype-2
		Fixed: note entry in sfx tracker is silent after running cartridge until pressing space to playback
		Fixed: sub("abc", 4, 4) returns "c" (regression in 0.2.4)
		Fixed: SPLORE cart update prompt does not appear when server replies too quickly (race condition)
		Fixed: SPLORE cart update prompt only checks version once per session (can't refresh until it shows up)
		Fixed: EXPORT command does not flatten includes when exporting to .p8.png / .p8.rom format
		Fixed: EXPORT command discards source code changes since last run or load
		Fixed: printing a one-off glyph using "\^." terminates the whole string when last byte is a zero
		Fixed: Crash when loading a cart with fewer tabs, then creating a new tab and pasting.
		Fixed: . command runs at 30fps even for a 60fps cart (-> _update60 is called twice, _draw once)
		Fixed: Custom menu items become broken after suspending a cart, entering a lua command, and then resuming
		Fixed: memset() with a non-zero value in shared memory region (0x1000..0x1fff) causes garbage corresponding mget() values
		Fixed: web player/exports: ctrl-r causes erroneous "external changes reloaded" message and code corruption


	v0.2.4

		Added: Video and spritesheet memory addresses can be mapped to each other
		Added: Map memory address can be mapped to 0x8000 // POKE(0x5f56, 0x80)
		Added: stat(46)..stat(56): higher resolution and more accurate reporting of audio state
		Added: Print one-off characters with ?"\^:447cb67c3e7f0106 hey" (or "\^." for binary data)
		Added: chr() can take multiple arguments to construct an arbitrarily long string
		Added: sub(str, pos, _) to get a single character at position pos
		Added: Warning on boot when PICO-8 is running below 30fps
		Added: Automatic scrolling caused by print() (with no x,y given) can be disabled with POKE(0x5f36,0x40)
		Added: .p8.rom format can be used by cstore(), reload() and in multicarts
		Added: EXPORT accepts .p8 .p8.png .p8.rom formats (can be used to save a copy, or convert from commandline)
		Added: 64-bit RaspberryPi OS Builds and Exporters
		Added: ASCII .txt version of manual included in archives & on website (synced with new html version)
		Added: Auto-hide mouse cursor when typing (adjustable in config.txt)
		Changed: .p8.rom file format can be less than 32k -- is padded with zeros to 32k on load
		Changed: sub() costs some cpu based on the length of the string
		Changed: Shorthand if/while no longer needs to be preceeded by a whitespace character or number
		Changed: load("#") throws a runtime error when cartridge id contains illegal characters
		Changed: 64k of Base RAM is standard (no need to set the hardware extension bit)
		Changed: By default, draw colour resets to 6 when program is suspended
		Changed: map() can take nil parameters for source_w, source_h to indicate default values
		Changed: pal(n) (a single integer) to reset a single palette 1..3 (draw, display, secondary)
		Changed: Can turn P8SCII wrap on/off with "\^$", "\^-$"
		Changed: config.txt is not saved on exit when changes are made to it while PICO-8 is open
		Changed: added code editor undo points when changing between identifier and non-identifier characters
		Changed: sfx(-1, -2) now behaves the same as sfx(-1). sfx(-2) stops looping on all channels.
		Changed: chip build no longer requires libcurl (calls out to wget)
		Fixed: (Mac, Linux) load("#`echo ohno`") is executed // + server-side mitigation for splore
		Fixed: stat(31) returns 2 parameters (bug introduced in 0.2.3)
		Fixed: split() and sub() fail on strings containing "\0"
		Fixed: ctrl-x on song pattern appears to work, but music() plays sfx 1..4
		Fixed: Text getting cut off after console scrolling when using print with draw_y_offset (0x5f5b)
		Fixed: camera(0,128) cursor(0,128) print("\n") causes unnecessary console scrolling
		Fixed: last music pattern not saved when only channel 3 is used and other channels are defaults
		Fixed: ?"\a12 sup yall" overwrites sfx 12 with a default beep (should just play and continue printing)
		Fixed: cursed console cpu refund exploit // https://carlc27843.itch.io/cursed-console
		Fixed: ctrl-r from commandline resets parameter string (stat(6)) -- should be same as the last run
		Fixed: ord() corrupting Lua stack and crashing when returning more than ~80 results
		Fixed: large camera() parameters can cause line() clipping to fail and crash
		Fixed: Crash when saving long gifs (> 90 seconds)
		Fixed: Unmapped joysticks not responding
		Fixed: Plugging in > 2 controllers causes other controller to disconnect


	v0.2.3

		Added: Lucky draw list in splore -- gives a random selection of carts
		Added: load/save carts in .p8.rom format (raw binary 32k block)
		Added: tostr(), tonum() take format_flags parameter to convert to and from 32-bit signed ints
		Added: ord(str, pos, num) returns num results starting from character at pos (similar to peek)
		Added: FOLDER takes an optional parameter to open other host directories: BACKUPS | DESKTOP | CONFIG | BBS
		Added: Live character / token count of selected text shown at bottom right of code editor
		Changed: Removed collaboration list from splore (can still search for sub:collab)
		Changed: 0x808 audio has a slight lpf filter on it by default // turn off by setting bit 0x20 at 0x5f36
		Changed: tonum(boolean_value) returns 1 or 0 instead of nil
		Changed: cursor CR x position set only by print(str,x,y) or cursor(), but not by print(str) (0x5f24)
		Changed: character wrap is on by default when using print(str)
		Changed: force-pause-menu hold duration is 500ms instead of 300ms to prevent accidentally triggering it
		Changed: default gif length for new install is 16 seconds
		Changed: ? shorthand can be used anywhere on a line e.g.  if (true) ?"yes"
		Changed: allow while/if shorthand with no statement, using colon separator: WHILE(BTN()==0);
		Changed: added warning to fullscreen_method 2 in config.txt (gives erratic behaviour under some drivers)
		Changed: cheaper OP_MOVE, OP_UNM lua vm instructions so that e.g. "local a=0-b" is not faster than "local a=-b"
		Fixed: peek*() / poke*() do not charge extra cpu when reading or writing multiple values
		Fixed: fget(n) returns junk when n is out of range (0..255); should return 0 in that case
		Fixed: dropped .PNG files not detected as images when filename uses uppercase extension
		Fixed: line()/tline() illegal writes caused by faulty clipping when (x1-x0) or (y1-y0) >= 0x8000
		Fixed: -accept_future 1 only worked with .p8.png files; now also applies to .p8
		Fixed: ?"\a7f" does not play f (happens only when f is the first note)
		Fixed: abs(0x8000) return 0x0.0001 (should be 0x7fff.ffff)
		Fixed: parameter string (stat(6)) is dropped when passed via RUN command
		Fixed: preprocessing of form: "x += x<0 and -1 or 1" broken for operators <, >
		Fixed: tab not accepted as whitespace for some preprocessor operations
		Fixed: stat(1) wraps around when cpu is >= 2.0 (regression in 0.2.2)
		Fixed: pressing SHIFT+ENTER on "local function foo()" or after "if (..) else" doesn't insert "end"
		Fixed: pal() does not reset secondary palette to system default
		Fixed: 0x808 audio does not respect pausing / volume / is not recorded with extcmd("audio_rec")
		Fixed: 'h' pressed in sprite editor toggles hex mode in map editor
		Fixed: After pressing shift-tab to toggle 128x128 map view, active draw area is still only 128x112
		Fixed: Attempt to navigate to non-existant tab after running: function _update60() _update60=nil end
		Fixed: stat(101) not returning cart id when running from BBS web player
		Fixed: print() wrapping + scrolling; e.g. from commandline: while(true) print(chr(254+rnd(2)).."\0")
		Fixed: integer divide assignment operator (\=) costs 2 tokens instead of 1 


	v0.2.2c

		Fixed: ?"\ac0" starts from d#0 instead of c0 (again -- 0.2.2b was still broken)
		Fixed: splore local directory navigation fails when using a relative home path set with -home 
		Fixed: export .lua.png only shows the first 2730 lines


	v0.2.2b

		Added: export foo.lua.png to get an image of the cartridge's source code
		Added: Pause menu can be forced to appear by holding down pause for 300ms (even if program blocks it)
		Added: extcmd("set_filename","foo") -- set the filename of the next screenshot or gif (can include %d)
		Added: extcmd("set_title","foo") -- set window title (useful for exported binaries)
		Added: Can toggle punyfont mode at command prompt w/ ctrl+p (useful for inspecting puny variable names!)
		Changed: Default filename is /untitled.p8 instead of no filename (auto-increments to untitled_1.p8 etc.)
		Changed: circ/oval that are not visible cost almost nothing, including circles that contain clipping region
		Changed: filled circles/ovals that contain clipping region cost the same as the equivalent rectfill
		Changed: shift+enter in code editor only auto-completes block for DO, THEN, REPEAT or FUNCTION 
		Fixed: ?"\ac0" starts from d#0 instead of c0
		Fixed: preprocessor regression when using string at end of ..= statement: if (true) then a..="b" end
		Fixed: pressing L / R in paused menu is registered by running program after closing menu
		Fixed: printing text in tall mode (?"\^ttall") via commandline can chop off bottom line before scrolling
		Fixed: drag-select text with cursor at bottom or top of screen scrolls too fast
		Fixed: spurious stat(0) results when using yield() to exit frame instead of flip()
		Fixed: line()/tline() sometimes draws pixels on opposite side of screen (0.2.2 regression)
		Fixed: line()/tline() fails to draw lines that have x or y coordinates > 32767 pixels apart 
		Fixed: can peek() more than 8192 values in single call
		Fixed: large fill circles (> radius 900) render incorrectly close to vertical center (32-bit builds, web)
		Fixed: even-widthed filled ovals with midpoint < 0 is drawn off by 1
		Fixed: black pixels in gif / map export not completely black
		Fixed: map and spritesheet exporters do not respect current display palette and 0x5F36:0x8 (draw spr 0)
		Fixed: code editor: cursor position off by one when selecting character after glyph (0.2.2 regression)
		Fixed: code editor: tab names don't show up when 100% punyfont
		Fixed: import spritesheet.png failing under MacOS (0.2.2 regression)
		Fixed: export single sfx to .wav crashes when contains sfx instrument references


	v0.2.2

		Added: SFX filters: noiz (white noise for inst 6), buzz, detune (flange/overtone), reverb, dampen (lpf)
		Added: SFX length (leave the second loop value at 0 to use). Can be >= 32.
		Added: P8SCII control characters when using print() -- can adjust colour and cursor position etc.
		Added: User-defined font at 0x5600, accessible via control character \014
		Added: poke(addr, val0, val1, val2 .. valn) -- same for poke2, poke4
		Added: can peek multiple values:  a,b,c = peek(addr, 3)  -- same for peek2, peek4
		Added: Locked mouse pointer // poke(0x5f2d, 0x5) and then stat(38),stat(39) to read
		Added: right click in sfx pitch mode to grab the instrument of that note
		Added: IMPORT command can specify target location in pixels: IMPORT FOO.PNG -X 16 -Y 32 
		Added: IMPORT -S to shrink the imported image (e.g. -S 3 means shrink from 384x384 -> 128x128) 
		Added: ctrl-c at empty command prompt to copy the most recent error message
		Added: extcmd("screen",0,1) / extcmd("video",0,1) saves files in same path as cart / exported executable or app.
		Added: set bit POKE(0x5F36, 0x8) to treat sprite 0 as opaque when drawn by map(), tline()
		Added: shift-tab in gfx/map editor for full-fullscreen mode (with no red menu bars)
		Added: extcmd("rec_frames") to record each gif frame only when flip() is called regardless of rendering speed
		Added: extcmd("folder") to open the folder on the host operating system (where printf, extcmd saves files to)
		Added: custom menu callbacks can optionally leave the pause menu open, and can read LEFT and RIGHT button presses
		Added: ctrl-h hex mode in map / gfx views (displays current sprite in hex, and shows map tile values)
		Added: export map as a single image with export foo.map.png
		Added: @weeble's gamepad improvements to the default html shell (dpad layout detection, better mapping / hotplugging)
		Added: stack trace on bad memory access e.g. poke(-1,0)
		Added: fillp can now be applied to sprite drawing (spr / sspr / map / tline), using colours from the secondary palette
		Improved: General optimisation pass; heavy carts use 20~30% less host cpu
		Changed: Most api functions are local by default for performance. use "pico8 -global_api 1" if needed for debugging.
		Changed: unpack() now has a non-zero cost but still fairly fast
		Changed: .. operator has a small cost based on number of characters concatenated
		Changed: LOADK vm instruction costs 1 cycles (was 2) // otherwise "c=0" costs more than "c=a+b"!
		Changed: removed function cpu refunds; speed-critical calls to bitwise function should use operator counterparts instead.
		Changed: Incremental garbage collection each frame for improved performance.
		Changed: stat(0) performs garbage collection in order to obtain a meaningful result; use stat(99) for raw value
		Changed: options menu always available from pause menu (used to only be available in web exports)
		Changed: tostr() returns "" instead of nil
		Changed: exporting gif/png from web version now creates a pop-up div that can be dismissed
		Changed: print() from commandline automatically wraps long strings
		Changed: print() returns the x position of the next character to be printed (can be used to calculate text width)
		Changed: glyph constants set only when running cartridge, not when running a command from prompt
		Changed: Using printh from exported carts outputs files in the same folder as the .exe / .app
		Changed: type() returns nothing instead of causing a runtime error
		Changed: fill pattern is cleared when program is suspended by default. Use poke(0x5f2e,0x20) to preserve.
		Changed: reset() resets everything from 0x5f00..0x5f7f, same as when program is initialised (including new random seed)
		Changed: font tweaks for hiragana, katagana, ampersand characters 
		Changed: (raspi) separate binaries that support gpio to remove wiringPi dependency and gpio poking-related crashes
		Fixed: Diagonal lines in editor contain an incorrect step when snapping to -1:1, 1:-1
		Fixed: rnd(tbl) is not random enough when table has 2 elements   /bbs/?pid=81092#p
		Fixed: add(tbl) causes runtime error. should have no effect and return nothing
		Fixed: cursor position in code editor incorrect when changing lines contaning glyphs/tabs
		Fixed: CONFIG TAB_WIDTH does not take effect until restarting PICO-8
		Fixed: Selecting sprites from bottom right -> top left and then pasting only pastes a single sprite
		Fixed: Moving map selection around with cursor keys beyond original selection leaves streaks
		Fixed: stdout/stdin serial() streams should be binary, not text mode (causes \r chars under Windows)
		Fixed: printh("hello.txt",fn,true,true) fails to save to desktop when fn has an extention
		Fixed: IMPORT FOO.PNG using the current sprite location as target instead of 0,0
		Fixed: tonum behaving differently to parser for string numbers out of range.  e.g. tonum("-0x9000") should be 0x7000
		Fixed: Exporting the same zip file multiple times creates duplicate file entries
		Fixed: tline / line clipping // sometimes off by 1px, sometimes incorrectly discarded altogether
		Fixed: poking values with bit 0x80 to 0x5f28,0x5f30,0x5f3c,0x5f3e clobbers following address
		Fixed: deli(tbl,nil) behaves the same as deli(tbl) -- should have no effect
		Fixed: stat(13),stat(15) reporting y coordinates of menu with 0 items
		Fixed: memory leak when saving gifs (causes web export to crash after a few records)
		Fixed: print() linefeeds clobber multi-line text printed at bottom of screen
		Fixed: preprocessor can not handle form: "::_::a+=1" (regression in 0.2.1)
		Fixed: When split() by group size (e.g. split("ab12",2,false)), last parameter ignored
		Fixed: partial cstore (len < 0x4300) from splore/export clobbering data outside that range on subsequent reload
		Fixed: joystick stops responding after unplug and plug back in twice (also happens when some devices sleep / wake up)
		Fixed: mkdir(nil) crashes
		Fixed: possible to edit an SFX without the cursor visible (confusing)
		Fixed: menuitem() callbacks broken when there is no _draw() or _update() defined
		Fixed: should only be able to call from commandline: cd mkdir install_games keyconfig info
		Fixed: controller menu (pause->options->controls) does not show custom key settings
		Fixed: -export failing to find files relative from current path
		Fixed: -export failing to locate html template path
		Fixed: binary export storing multicart cart names with path (should be named "dat1.p8", not "dat/dat1.p8")
		Fixed: pause menu broken when cartridge is launched from splore and run() is called inside first frame 
		Fixed: text printing does not respect draw palette (was broken in 0.2) // ref: /bbs/?tid=41428
		Fixed: for backwards compatibility, non-numbery colour parameters should be taken to mean zero
		Fixed: preprocessor: self assignment with quoted function calls on RHS a+=1+cos"0"
		Fixed: ctrl-r during pause menu only takes effect after closing menu
		Fixed: (bug in RC1) pack(...).n is zero
		Fixed: (bug in RC1) using filters noiz:1, dampen:2, lpf is not applied to melodic instruments (but should be)


	v0.2.1b

		Added: split(str,"") splits by single characters
		Updated: Tower of Archeos 1.1 via INSTALL GAMES
		Fixed: print(num,x,y) always prints numbers num in hexidecimal
		Fixed: .p8.png decoder can enter an infinite loop (caused exports to freeze on boot)
		Fixed: Can't save screenshot/gif when running a BBS cart with illegal characters in title.
		Fixed: INSTALL_GAMES is broken
		Fixed: Mouse is broken in HTML exports


	v0.2.1

		Added: oval() ovalfill() split()
		Added: circle drawing tool is now an oval tool (hold shift for circle)
		Added: hold shift with line tool to snap to 22.5 degree angles from origin (0:1, 1:1, 2:1 gradients)
		Added: serial() channels for stdin,stdout
		Added: raw binary and image files dropped in to PICO-8 also become byte streams readable w/ serial()
		Added: add(tbl, val, index) -- insert val into table at index
		Added: deli(tbl, index) -- delete element from table by index (index defaults to last element)
		Added: show progress while exporting binaries (can be slow now that generating zip files)
		Added: -e to add an extra file to exported binaries zip files // export -e manual.txt foo.bin
		Added: RESET command to reset the runtime / draw state
		Added: drag and drop cartridges into PICO-8 window to load them
		Added: hash stored in .p8.png so that cartridges corrupted by image quantization can show a specific error
		Added: raw data blocks in compressed code format (useful for storing long binary strings efficiently)
		Added: clip(x,y,w,h,true): 5th parameter indicates that the clipping region should be clipped by the old one
		Added: -export switch can be used to convert .p8 files to .p8.png from commandline. // pico8 foo.p8 -export foo.p8.png
		Added: extcmd("screen",scale) and extcmd("video",scale) to override the default scale (e.g. scale 2 means 256x256)
		Added: printh(str, filename, overwrite, save_to_desktop) -- 4th parameter to save output file to desktop
		Changed: add(), del() no longer implemented with Lua snippet; lower cpu cost.
		Changed: line(),rect() cost the same as rectfill() when drawing equivalent shapes
		Changed: all drawing operations in sprite editor now observe fill pattern state
		Changed: numbers can be immediately followed by identifiers (a=1b=2) // lexaloffle.com/bbs/?tid=38038		
		Changed: Sprite editor shows only active area after shift-selecting sprites
		Changed: copy/paste in the code editor treats uppercase ascii characters as puny font only when puny mode (ctrl+p) enabled
		Changed: C0 Controls characters (except for 0x0,0x9,0xa,0xd) encoded in .p8 / clipboard with unicode replacements
		Changed: stat(4) converts characters to PICO-8 format (P -> puny p,  hiragana unicode -> single character etc.)
		Changed: serial() returns number of bytes processed (1/8ths included for partial bytes)
		Changed: IMPORT SPRITESHEET.PNG now uses the current sprite as the destination coordinate instead of 0,0.
		Changed: Standardized name of the display palette to "display palette" (was sometimes referred to as "screen palette").
		Changed: tostr() returns nil (used to return "[nil]")
		Changed: don't need to set bit 0x40 at address 0x5f2c to use secondary palette.
		Improved: exported binary's data.pod file 90% smaller (~870k -> ~85k)
		Fixed: pack(...).n is shifted right 16 bits
		Fixed: ctrl-r doesn't reload external changes for carts which are over compressed code capacity
		Fixed: false positives when detecting external changes for some older cart versions
		Fixed: .p8.png carts saved with dense code (compressed size > raw size, including very small carts) stores junk
		Fixed: error message duplication when loading future version of .p8.png carts
		Fixed: Illegal colours can enter spritesheet via serach-replace after setting with color()
		Fixed: Preprocessor: "foo():a().x+=1" "a=b[1]c+=1"
		Fixed: hex numbers written with punyfont characters breaks syntax high-lighting
		Fixed: shift+- in sprite editor jumps too far vertically when zoomed in
		Fixed: clicking a note in sfx editor creates a selection (-> backspace clears without moving rows)
		Fixed: print()/printh()/stop() doesn't respect __tostring metatable method (regression)
		Fixed: time() and btnp() speed changes after stopping program, typing a command and then resuming.
		Fixed: phantom drag & drop events sent to unused music channels causing them to occasionally unmute themselves
		Fixed: undo after moving sprites in map mode only undoes the changes to the map and not the spritesheet.
		Fixed: inconsistent token counting for negative or bnot'ed numbers https://www.lexaloffle.com/bbs/?tid=38344
		Fixed: Crash when INSTALL_GAMES / INSTALL_DEMOS without a writeable disk
		Fixed: stat(4) (clipboard contents) does not convert unicode to corresponding glyphs
		Fixed: (MacOS) Using discrete GPU ~ drains battery. Now using integrated GPU when available.
		Fixed: screensaver is blocked while PICO-8 is running (needed to set SDL_HINT_VIDEO_ALLOW_SCREENSAVER: "1")
		Fixed: screen glitches after running for 25 days
		Fixed: (HTML Exports) touch controls not registering when running under iOS from an iframe (e.g. on an itch.io page) 
		Fixed: (HTML Exports) tap and hold brings up the select menu under iOS
		Fixed: (HTML Exports) button blocked by canvas when overlapping on small screens



	v0.2.0i

		Added: pack(), unpack()
		Changed: bitplane read/write mask only reset after finished running program
		Fixed: tline() doesn't draw anything when the layers argument is not given


	v0.2.0h

		Added: tline() takes an optional layers parameter, similar to map()
		Added: high bits of 0x5f5e taken as colour read mask, low taken to be colour write mask
		Added: Double-click in the sfx tracker to select all attributes of a single note.
		Fixed: assignment shorthand RHS scope wrong when contains certain operators. e.g. a+=1&127
		Fixed: while/if shorthands fail when "do" or "then" appears on the same line as part of an identifier
		Fixed: ctrl-c copies the wrong sfx after clicking pencil button (next to pattern #) in organiser view
		Fixed: spinning cart icon present in video memory when cart boots from splore


	v0.2.0g

		Added: Window title shows current cartridge filename while editing
		Changed: ~ preceeding a numerical constant (e.g. ~1) counts as a single token
		Fixed: >>> operator behaviour does not match lshr(a,b) when b >= 32 (again)
		Fixed: PICO-8 freezes when shift by -0x8000 
		Fixed: .p8 format does not store extpal label colours
		Fixed: Can not save screenshot when filename contains ":"


	v0.2.0f

		Changed: @@ operator (peek2) to %
		Fixed: Exported wasm crashes on boot when code contains a numerical constant out of range.
		Fixed: HTML Shell treats controller shoulder buttons as MENU; easy to accidentally bump.
		Fixed: shift operators behaviour undefined for negative values of n (now: x << n means x >> -(n\1))
		Fixed: >>> operator behaviour does not match lshr(a,b) when b >= 32
		Fixed: INFO crashes when code is close to 64k of random characters
		Fixed: Code editor undo step not stored when starting to edit a new line (hard to see what happened)


	v0.2.0e

		Added: zip file creation (with preserved file attributes) when exporting binaries
		Added: cpu working animation when cpu usage > 120 skipped frames
		Improved: stop() / resume now works at the instruction level
		Fixed: tline clipping broken (from 0.2.0d)
		Fixed: cpu counting is wrong inside coroutines
		Fixed: coroutines interrupted by garbage collection
		Fixed: code compression suddenly much worse for carts > 32k chars
		Fixed: code compression ratio can be less than 1 in extreme cases		
		Fixed: pasting a string ending in '1' into the command prompt opens the editor
		Fixed: html export can run out of pre-allocated heap when doing heavy string operations
		Fixed: hex memory addresses displayed in puny font on windows
		Fixed: devkit mouse message shown once per cart -- should be once per chain of carts
		Fixed: can't paste sfx notes after moving to another sfx via keyboard
		Fixed: copying note select vs. sfx vs. pattern range is ambiguous
		Fixed: crash after redefining type()


	v0.2.0d

		Added: rnd(x) when x is an array-style table, returns a random item from that table
		Added: gif_reset_mode (in config.txt / CONFIG command). Defaults to 0.1.12c behaviour
		Added: print(str, col) form behaves the same as: color(col) print(str)
		Added: Operators: <<> >>< <<>= >><=
		Changed: tline now also observes an offset (0x5f3a, 0x5f3b)
		Changed: tline rounds down to integer screen coordinates (same as line)
		Changed: Final cpu adjustments (see release post)
		Changed: Removed experimental "!"->"this" shorthand
		Changed: clip() returns previous state as 4 return values
		Fixed: Included files remain locked (and can not be edited by external editors)
		Fixed: Carts loaded as plaintext .lua fail to handle BOM / DOS characters
		Fixed: palt() returns previous state of bitfield as a boolean instead of a number
		Fixed: CPU speed on widget doesn't exactly match stat(1)
		Fixed: stat(1) occasionally reports garbage values when above 1.0
		Fixed: Custom btnp repeat rates (0x5f5c, 0x5f5d) speed up when skipping frames
		Fixed: gif_scale setting not read from config.txt
		Fixed: tline: texture references are incorrect when sy1 < sy0
		Fixed: tline: single pixel spans are drawn as two pixels
		Fixed: binary exports' controls menu always shows 0 joyticks connected
		Fixed: Pressing DEL on first row of tracker doesn't do anything
		Fixed: host framerate regulation is slow (~1/sec) when PICO-8 frame takes < 1ms to execute
		Fixed: fillp() return value (previous state) does not include transparency bit
		Fixed: clip"" setting all clip values to 0 (should be ignored)
		Fixed: Raspberry Pi static build / static export requires GLIBC 2.0.29 (now .16)
		Fixed: stop(nil) crashes 
		Fixed: print(), printh(), stop() prints "nil" with no arguments (should have no output)
		Fixed: trace() can not be used with coroutines


	v0.2.0c

		Changed: Compressed size limit now 0x3d00 bytes (reclaimed an unused 0x100 byte block)
		Fixed: >>>= operator (was doing a >>= replacement instead) 
		Fixed: #including large .lua files causes crashes, weird behaviour
		Fixed: Sandboxed CSTORE: writing partial data to another embedded cart clobbers the remaining data.
		Fixed: Multicart code storing regression introduced in 0.2.0 (code from head cart stored in other carts)
		Fixed: Can not edit spritesheet after panning
		Fixed: Junk error messages when syntax error contains one of the new operators
		Fixed: Crash with: 0x8000 / 1 


	v0.2.0b

		Changed: #include directive can be preceeded by whitespace 
		Changed: Activity logger records nothing after idle for 30 seconds
		Fixed: Mouse cursor movement in editor is not smooth
		Fixed: Display palette doesn't reset after exiting splore
		Fixed: PALT() returns 0 instead of previous state as bitfield
		Fixed: Rectangle and line tools broken when used in map editor
		Fixed: INSTALL_GAMES under Windows produces broken cart files
		Fixed: Stored multicart sometimes has code section truncated (fails to load())


	v0.2.0

		Added: 8-bit character set with kana, alt font
		Added: ord(), chr()
		Added: SFX / Pattern organiser view
		Added: SFX edit buttons on pattern channels
		Added: tline // textured line drawing
		Added: SPLORE automatically updates BBS carts when online
		Added: Search for similar (shared tags) cartridges, or by thread
		Added: predefined fillp() pattern values assigned to glyphs
		Added: btnp() custom delays (poke 0x5f5c, 0x5f5d)
		Added: "." shorthand command for advancing a single frame (calls _update, _draw if they exist)
		Added: Current editor/cart view is recorded every 3 seconds to [app_data]/activity_log.txt
		Added: Cutting (ctrl-x) and pasting selected sprites while in map view to also adjust map references to those sprites
		Added: Clipboard is supported in the html exports (with some limitations) // load #wobblepaint for an example.
		Added: Can load .lua files as cartridges
		Added: Operators: ..= ^= \ \= & | ^^ << >> >>> ~ &= |= ^^= <<= >>= >>>= @ @@(update: @@ replaced with %) $
		Added: New demo carts: waves.p8 dots3d.p8 automata.p8 wander.p8 cast.p8 jelpi.p8 (use INSTALL_DEMOS)
		Added: Extra pre-installed games: Embrace, 8 Legs to Love (use INSTALL_GAMES)
		Added: Splore cart labels for .p8 files
		Added: Now 16 code tabs (click on the rightmost ones to scroll)
		Added: ipairs()
		Added: SAVE from commandline to quick-save current cartridge (same as ctrl-s) 
		Added: BACKUP from commandline to save a backup of current cartridge
		Added: CPU usage widget (ctrl-p while running cartridge)
		Added: Button / dpad states exposed in memory at 0x5f4c (8 bytes)
		Added: Random number generator state exposed at 0x5f44 (8 bytes)
		Added: pico8_dyn version is included when exporting to Raspberry Pi
		Added: allow_function_keys option in config.txt (CTRL 6..9 are now preferred -- will phase out F6..F9 if practical)
		Added: Visible tab characters (draw_tabs in config.txt)
		Added: pal({1,2,3..}) means: use the value for each key 0..15 in a table
		Added: palt(bitfield) means: set the colour transparency for all 16 colours, starting with the highest bit
		Added: Options menu for binary exports (sound / fullscreen / controls)
		Added: Shape drawing tools in sprite and map editor
		Improved: Miscellaneous HTML shell / player optimisations and adjustments
		Improved: Lower cpu usage for small foreground_sleep_ms values (changed host event loop & fps switching strategy)
		Changed: This update is called 0.2.0, not 0.1.12d! (grew into plans for 0.2.0, and bumped cart version number)
		ChangeD: Reverted cheaper 0.1.12* costs on bitwise operators & peek (recommend replacing with operators if need)
		Changed: negative numbers expressed with a '-' count as a single token
		Changed: glitchy reset effect does not leave residue in base RAM (but maybe on screen when using sprites / tiles)
		Changed: sset() with 2 parameters uses the draw state colour as default
		Changed: line() or line(col) can be used to skip drawing and set the (line_x1, line_y1) state on the next call to line(x1,y1)
		Changed: vital system functions (load, reboot etc.) can only be overwritten during cartridge execution  
		Changed: sqrt(x) is now more accurate, and a little faster than x^.5
		Changed: sqrt(x) returns 0 for negative values of x
		Changed: btnp() delay and repeats now work independently per-button
		Changed: pairs(nil) returns an empty function
		Changed: Default screenshot scale (now 4x), gif scale (now 3x)
		Changed: gif_len now means the length when no start point is specified (used to be the maximum recordable length)
		Changed: (Multicarts) When loading data from many different carts, the swap delay maxes out at ~2 seconds
		Changed: (Raspberry Pi) removed support for (and dependency on) libsndio
		Changed: camera(), cursor(), color(), pal(), palt(), fillp(), clip() return their previous state
		Changed: Can not call folder() from a BBS cart running under splore
		Changed: F9 resets the video, so that multiple presses results in a sequence of clips that can be joined to together
		Changed: color() defaults to 6 (was 0)
		Changed: Backed up filenames are prefixed with a timestamp.
		Changed: Automatically start on the (host's) current path if it is inside PICO-8's root path
		Changed: tostr(x,true) can also be used to view the hex value of functions and tables (uses Lua's tostring)
		Changed: Can hold control when clicking number fields (spd, pattern index etc.) to increment/decrement by 4 (was shift)
		Fixed: HTML exports running at 60fps sometimes appear to repeatedly speed up and slow down
		Fixed: HTML export layout: sometimes broken -- option buttons overlapping in the same place 
		Fixed: __tostring metatable methods not observed by tostr() / print() / printh()
		Fixed: Mac OSX keyboard permissions (fixed in SDL2 0.2.12)
		Fixed: Audio mixer: SFX with loop_end > 32 would sometimes fail to loop back
		Fixed: btn() firing a frame late, and not on the same frame as stat(30)
		Fixed: #include can not handle files saved by some Windows text editors in default format (w/ BOM / CRLF)
		Fixed: Exports do not flatten #include'd files
		Fixed: Default window size has too much black border (now reverted to previous default)
		Fixed: Functions yielded inbetween frames occasionally push an extra return value (type:function) to the stack
		Fixed: can't load png-encoded carts with code that starts with a :
		Fixed: .gif output unnecessarily large
		Fixed: .gif recording skipping frames when running at 15fps	
		Fixed: printh does not convert to unicode when writing to console or to a file
		Fixed: cart data sometimes not flushed when loading another cart during runtime
		Fixed: Can not navigate patterns with -,+ during music playback
		Fixed: Mouse cursor not a hand over some buttons
		Fixed: Laggy mouseover messages (e.g. showing current colour index, or map coordinates)
		Fixed: Can't paste glyphs into search field
		Fixed: Tab spacing always jumps config.tab_spaces instead of snapping to next column
		Fixed: -p switch name is wrong (was only accepting "-param" in 0.12.*
		Fixed: Code editor highlighting goes out of sync after some operations
		Fixed: Multicart communication problem (affecting PICOWARE)
		Fixed: time() speeds up after using the RESUME command
		Fixed: Audio state is clobbered when using the RESUME command
		Fixed: Audio glitch when fading out music containing slide effect (1)
		Fixed: Toggling sound from splore cart->options menu has no effect
		Fixed: Devkit keyboard works when paused
		Fixed: "-32768 % y" gives wrong results
		Fixed: Replacing all text in code editor breaks undo history
		Fixed: Double click to select last word in code does not include the last character
		Fixed: Weird block comment behavior in code editor
		Fixed: HTML export: cart names can not contain quotes
		Fixed: HTML export: menu button layout under chromium
		Fixed: HTML export: Adding content above cartridge breaks mobile layout
		Fixed: HTML export: Can touch-drag PICO-8 screen around (breaks simulated mouse input)
		Fixed: LOAD("#ABC") does not always immediately yield
		Fixed: Infinite RUN() loop crashes PICO-8
		Fixed: Mouse cursor is not a finger on top of most "pressable" button-style elements
		Fixed: CD command fails when root_path is relative (e.g. "pico8 -root_path .")
		Fixed: poke in fill pattern addresses (0x5f31..0x5f33) discards some bits
		Fixed: After using ctrl-click in map editor, can not modify map outside that region
		Fixed: Shift-selecting sprites from bottom right to top left selects wrong region
		Fixed: Changing GIF_LEN from PICO-8 commandline sometimes breaks gif saving
		Fixed: pget() sometimes returns values with high bits set
		Fixed: Preprocessor: unary operator lhs is not separated in some cases (e.g. x=1y+=1)
		Fixed: Preprocessor: ? shorthand prevents other preprocess replacements on same line
		Fixed: Preprocessor: fails when multiple shorthand expressions + strings containing brackets appear on the same line
		Fixed: Loading a .p8 file with too many tabs discards the excess code.
		Fixed: Map editor's stamp tool wraps around when stamping overlapping the right edge.
		Fixed: Very quick/light tap events sometimes do not register
		Fixed: SFX tracker mode: can't copy notes with shift-cursors before clicking (whole sfx is copied instead)
		Fixed: "..." breaks syntax highlighting
		Fixed: Click on text, press up/down -> cursor reverts to previous horizontal position
		Fixed: CTRL-[a..z] combinations processed twice under some linux window managers
		Fixed: ctrl-up/down to jump to functions in the code editor breaks when "function" is followed by a tab
		Fixed: map & gfx drawing selection is not applied consistently between tools
		Fixed: Using right mouse button to pick up a colour / tile value sometimes also applies current tool


	v0.1.12c

		Fixed: CPU usage reported by stat(1) is higher than actual value
		Fixed: Fail to load .p8 cartridges w/ BOM marker / CRLF endlines
		Fixed: Syntax errors / crash caused by #including files containing BOM / CRLFs
		Fixed: Can not save .p8 when contains unresolved #includes
		Fixed: Can't open pico-8.txt in Notepad.exe (added CRLFs)
		Fixed: Can delete null terminator at end of code (revealing previously deleted code)


	v0.1.12b

		Added: config command (e.g. CONFIG THEME CLASSIC)
		Fixed: Windows sound resampling artifacts (moved to SDL2 2.0.9 audio:directsound)
		Fixed: Glyphs stored as unicode can not load when #include'd		
		Fixed: Code highlighting is wrong after select and delete a line
		Fixed: Last line endpoint not present in draw state memory
		Fixed: Ubuntu 16.04 can not run because requires glibc 2.27 (reduced dependency to 2.14)
		Fixed: stat(102) returns nil when run from binary instead of 0 (now 0)
		Fixed: Loading cartridge from commandline fails when path contains "../"
		Fixed: (OSX) Crash when reloading external changes with CTRL-R
		Fixed: (Windows) Crash when running cart with included code		
		Fixed: Can not export or include extra cartridges outside of current directory
		Fixed: Off by 1 when search for line 1 (affected ctrl-b, ctrl-l)
		Fixed: html template -- mouse cursor showing over canvas (now hidden by default)


	v0.1.12

		Added: #include a text file, or a tab from another cartridge
		Added: Unlimited undo for gfx,map,sfx
		Added: [sfx] snippets: copy and paste sound & music between PICO-8 instances and BBS posts
		Added: (BBS) sfx snippet player
		Added: CTRL-G in code editor to repeat search across all tabs
		Added: Splore search text entry with cursor key button presses
		Added: Custom tab widths (tab_width in config.txt)
		Added: Web exporter template: joystick & touch support, preview image, menu buttons, adaptive size, controls screen
		Added: .wasm exporter (use -w)
		Added: Raspberry Pi binary exporter
		Added: -export // run the EXPORT command from host commandline
		Added: Toggle flags on multiple sprites at once by selecting them first
		Added: Confirmations when loading/saving with unsaved changes
		Added: Windowed mode support for Raspberry Pi
		Added: serial() interface for Raspberry Pi // serial() -- spi, ws281x, direct bit banging // 0.2.1 update: dropped spi
		Added: api: peek2 poke2 rawset rawget rawlen rawequal next
		Added: Comment/uncomment selected block with CTRL-B
		Added: Can save screenshots and gifs from exported binaries via EXTCMD
		Added: Can exit exported binaries after runtime error / stop(), and also via EXTCMD("SHUTDOWN")
		Added: SHUTDOWN menu item added to pause menu when running via "-run cartfile"
		Added: -kiosk to run in kiosk mode: boot into splore, favourites menu only, no cart menu
		Added: -root_path to set root cartridges folder from commandline
		Added: shift+space in song view to play from the current quarter of the selected channel
		Added: CTRL-W, CTRL-E in code editor to jump to start / end of line
		Added: -accept_future to load cartides made with future versions of PICO-8
		Added: -preblit_scale (default: auto) for less blurry scaling with -pixel_perfect 0
		Added: -pixel_perfect -1 (auto) only uses pixel perfect scaling when < 10% of the containing screen axis is wasted
		Added: highlight all occurances when searching for text in code editor 
		Added: tab completion across directories
		Added: In map editor, non-zero cels that are drawn all black are marked with a single blue dot
		Changed: all(), foreach() cpu cost is now much cheaper (but still a little more than using a for loop)
		Changed: cursor() can also set the current color with a third parameter
		Changed: stat 24..26 return -1 when no music is playing
		Changed: 3x4 font characters (uppercase in ascii) allowed in code editor (but not pasteable/editable)
		Changed: time() / t() always means seconds since run (but still updated once per _update() / _update60)
		Changed: line(x1,y1) can be used to draw from the end of the last line
		Changed: del() returns the item deleted on success
		Changed: single setting for audio volume (-volume switch, "volume" in config.txt)
		Changed: allow '-' in cartdat() names
		Changed: 8 and - only map to buttons 4 and 5 by default for CHIP build
		Changed: Raspberry Pi pico8_dyn build does not support gpio/serial (and so does not require wiringPi)
		Changed: Default theme is 1 (blue background in code editor)
		Changed: When loading a cart from commandline, automatically set the current path if inside PICO-8's filesystem 
		Fixed: Code editor uses too much cpu / battery power
		Fixed: cstore() with an external cart name broken when run from exported cart or as bbs cart
		Fixed: Undoing changes to SFX after using pitch drawing tool clears SFX data
		Fixed: Running headless scripts under Windows / Mac OSX crashes
		Fixed: Running headless scripts with no video driver fails
		Fixed: Can not load BBS carts in headless script mode (without auto-running)
		Fixed: (Web exporter) mouse cursor doesn't work in fullscreen
		Fixed: (Web exporter) mouse button 2 brings up context menu
		Fixed: (Web exporter) Clusters of FS.syncfs calls causing error messages (and inefficient?)
		Fixed: (Windows) PICO-8 behaves as if it is not the foreground application
		Fixed: divide and abs sign flipping for 0x8000.0000
		Fixed: sqrt(0x0000.0001) freezes
		Fixed: "-1"+0 evaluates to 0xffff.0001
		Fixed: shift-tabbing to unindent alters selection range
		Fixed: background_sleep_ms reverts to default value
		Fixed: "open in thread" option appears for local carts
		Fixed: (code editor) undo markers in unexpected places
		Fixed: root_path, desktop_path in config.txt doesn't work without trailing slash
		Fixed: Audio sampling rate is wrong when device/driver doesn't support 22050MHz
		Fixed: Loading cart with less than 5 pixel rows of gfx does not clear default white cross sprite
		Fixed: cpu cycle exploit using peek4 with no parameters
		Fixed: SFX keyboard editing operations (e.g. SPD +/-) sometimes applied to the wrong SFX
		Fixed: Cursor behaviour when moving between song and sfx view, and when playing music
		Fixed: Selecting SFX notes with shift + home/end/pgup/pgdown
		Fixed: Vibrato (2) and drop (3) effects in SFX instruments not observed
		Fixed: Can not place note at C-0 in pitch mode
		Fixed: CTRL-F search in code skips matches that are close together
		Fixed: (Mac) warning about unoptimized program (built with SDL 2.0.9, + now 64-bit)
		Fixed: (Raspberry Pi) Keypresses leaking to desktop
		Fixed: (Raspberry Pi) Keyboard layout fixed to US
		Fixed: printh(nil) prints [false] instead of [nil]
		Fixed: toggling audio mute twice returns to maximum volume
		Fixed: alt+cursors moves cursor in code editor
		Fixed: del does not work on first character of code or commandline
		Fixed: preprocessor breaks on double slash in string s="\\"
		Fixed: sometimes code executing a little after point of runtime error
		Fixed: Token count reported in editor is more than 0 after rebooting
		Fixed: "Removed empty tabs" message displayed when loading cart with fewer tabs
		Fixed: Member variables highlighted when same as API function names (e.g. actor.spr)
		Fixed: Hot-plugged joysticks not recognized


	v0.1.11g
		
		Added: CTRL-C to copy contents of commandline
		Added: stat(100..102) for current breadcrumb label, bbs cart id, and hostname (web)
		Added: content_filter in config.txt
		Added: Cartverse cart id support (not live server-side yet though)
		Fixed: Tab preview does not show on mouseover
		Fixed: Can't paste uppercase characters into commandline
		Fixed: Preprocessor can't handle glyphs in form: "♥.x += 1"
		Fixed: Unsaved changes sometimes reported when filename is not set
		Fixed: Pause menu doesn't open inside infinite loop inside _draw
		Fixed: load() crashes when "parameter string" parameter is not a string
		Fixed: cstore(),reload() crash when external cart filename is not a string
		Fixed: printh(str, "@clip") fails for glyph characters in str


	v0.1.11f

		Fixed: Pause menu doesn't open inside an infinite loop
		Fixed: Binary and hex string digits outside of 0xffff.ffff alter result


	v0.1.11e

		Added: stat(30..31) for devkit keyboard input
		Added: extcmd("pause") extcmd("reset") extcmd("breadcrumb")
		Added: lshr(), ceil(), rotl(), rotr(), peek4(), poke4()
		Added: stat(12..15) to grab the position of the pause menu (x0,y0,y1,y1)
		Added: DPAD game controller buttons mapped to LRUD
		Added: CTRL-click on song navigator to scroll by 4 patterns
		Added: Can type and paste glyphs in commandline
		Added: Notification when CTRL-R fails to reload because of unsaved changes
		Added: Notification when code automatically converted to lower-case
		Added: INFO() checks for "external changes" (e.g. when using a separate text editor)
		Added: .p8.png format can be used with cstore() and carts bundled in multicarts
		Added: Can optionally set fill pattern using colour parameter 
		Changed: Glyphs can be used as variable names
		Changed: Glyphs stored in clipboard and .p8 format as roughly corresponding unicode
		Changed: .p8 format skips storing tailing rows of data that match default state
		Changed/Fixed: shr(x,n) is now equivalent to calling shr(x,1) n times when n >= 32
		Fixed: Error message and stack trace line numbers 0 or slightly out
		Fixed: Unclosed block error navigates cursor to <eof> rather than start of block
		Fixed: Exported binaries can load carts outside of bundle
		Fixed: BBS cart loaded from a local cart loses data cstore()ed during previous run
		Fixed: btn() returns same as btnp()
		Fixed: btnp(6) always returns false
		Fixed: Missing mask pixels in cart download animation frame
		Fixed: Crash when try to load a directory as a cart
		Fixed: Sometimes cursor position set by keyboard mouse emulation in code editor
		
		
	v0.1.11d

		Added: t() aliased to time()
		Fixed: time() always returns 0 when there is no _update function
		Fixed: (raspi) Keyboard stops responding after pressing CTRL-F, CTRL-Z
		Fixed: (raspi) Double keypresses in sound editor when entering notes
		Fixed: stat(6) pads parameter string with spaces

	
	v0.1.11c
		
		Added: Local and UT time queries using stat()
		Added: host_framerate_control (config.txt) to improve performance on slower machines and web 
		Added: Control over cpu usage when running in background (-background_sleep_ms / config.txt)
		Added: Windows icon in exported exe
		Added: F11 to toggle fullscreen
		Added: export -c switch to indicate transparent icon colour 
		Added: show_backup_messages (config.txt) to turn off backup notifications
		Added: SFX instruments documentation in pico8.txt
		Added: Error message when trying to export carts with code size over the compressed limit
		Changed: If config.txt is not found, the same directory as the executable is searched
		Changed: If sdl_controllers.txt exists in the same directory as the executeable, it is processed first
		Changed: Shorthand if () statements must be written on a single line
		Fixed: reload() from bundled, non-primary cart in exported html multicart reads only original data
		Fixed: Exported binaries wrongly observe F7 (capture label)
		Fixed: Loading carts from earlier versions alters SFX data not intended for audio
		Fixed: Old version of fill patterns documentation near end of pico8.txt
		Fixed: 'backed up unsaved changes' message displayed during runtime for cstored() carts
		Fixed: PICO-8 runs too slowly when in background (new default background_sleep_ms: 20)
		Fixed: Saving screenshots and videos from exported binaries are named 0_*
		Fixed: Compressed size limit warning on save doesn't mention exported carts
		Fixed: btn(), btnp() don't work in infinite loops
		Fixed: btnp() timing inconsistent between 30fps / 60fps / during frame-skipping / with no _update
		Fixed: Can't move between channels while music is playing in song mode


	v0.1.11b
	
		Fixed: Preprocessor bug regressions: "if (..) or", "a.b -= c - d"
		Fixed: Crash when pressing menu button on an empty favourites list


	v0.1.11
		
		Added: Binary exporters (Windows, Linux, Mac OSX)
		Added: Code tabs
		Added: Splore cart menu
		Added: Fill patterns
		Added: Custom sfx instruments
		Added: load("#1234") to load [and run] a BBS cart
		Added: -x switch // execute a cart headless, for making commandline toolchains
		Added: Compressed size display and limit warning lights in code editor
		Added: CTRL-L to jump to a line number in code editor
		Added: numbers can be written in binary: 0b10100010 
		Added: tostr(), tonum()
		Added: extcmd(): audio_rec, audio_end to record all audio output.
		Added: ls() returns a list of local files if called while running
		Added: getmetatable()
		Added: coroutine error reporting // wrap coresume() in assert()
		Added: sfx() can take a 4th parameter: number of notes to play
		Added: Live sfx and music editing + better navigation controls
		Added: Transpose selected sfx notes relative to C by entering a note w/ SHIFT held
		Added: Insert and delete sfx rows with enter and backspace
		Added: Hidden note data is shown in sfx editor when relevant (slide, arps)
		Added: Warning displayed when unsaved changes backed up
		Added: Separate animation for downloading vs. loading a cart
		Added: export -p switch to supply a customized html template 
		Added: Mousewheel when devkit mouse enabled: stat(36) // not supported in web
		Added: < > to change zoom level in gfx and map editors
		Changed: Rebalanced / fixed api cpu costs
		Changed: Screenshot and gif filenames based on current cart if available
		Changed: add() returns the added object
		Changed: removed global hpf on audio
		Changed: (sfx) can slide to volume 0
		Changed: removed master low pass filter
		Changed: assert() can take an optional error_message parameter
		Changed: ? (shorthand for print()) can be prefixed by whitespace 
		Changed: shl(), shr() return 0 if second parameter >= 32
		Changed: Automatically drop down to software blitting mode if opengl fails
		Changed: Lua memory limit set to 2MB (was 1MB)
		Changed: Some options (-width, -show_fps) apply only to the session; not saved to config.txt
		Updated: Internal game controller mappings from SDL_GameControllerDB
		Fixed: Pops & clicks in audio when switching between playing SFX
		Fixed: Crash in audio mixer because of bad locking
		Fixed: Crash when loading .p8 files with more than 64k of code
		Fixed: Indexing of sparse tables fails after removing n/2 elements
		Fixed: Calling stat() inside an infinite loop crashes
		Fixed: Resetting cartridge corrupts cartridge data in range 0x5e00..0x5eff
		Fixed: Can not recover from a cart error caused by glitchy data on resetting 
		Fixed: String->negative number conversion off by 0x0.0001 (-1 --> 0xffff0001)
		Fixed: Crash when running cart closed to 64k char limit
		Fixed: Cursor can't move to the right of last character in code editor
		Fixed: Missing highlighted keywords: in, add, del, menuitem
		Fixed: Preprocessor bugs: "a+=1+2\n*3", "a+=(1)ba=42", "a[(1)]+=1"
		Fixed: Preprocessor performs replacements inside a string printed with ?
		Fixed: Display freezes when terminating a program running at >100% cpu
		Fixed: Quick-running (CTRL-R) clobbers some editor state (e.g. current sprite page)
		Fixed: Loading a .p8 file with a future version reports a generic failure
		Fixed: alt-enter to toggle fullscreen also triggers pause menu
		Fixed: Splore scrolling jumps around when list gets too long


	v0.1.10c
	
		Fixed: atan flips sign for very negative values of x close to zero


	v0.1.10b
		Fixed: HTML exporter carts don't run
		Fixed: HTML export 60fps support broken
		Fixed: HTML export when path has a space in it (common for OSX)
		Fixed: atan2 ignores sign of y
		Fixed: (Raspberry Pi) Crash when access gpio not as root
		

	v0.1.10
	
		Added: Multi-cart export in html
		Added: Cart reset glitch
		Added: Demo carts: bounce, sort
		Added: .p8 format can now store cart labels
		Added: Splore navigation keys: pageup/down, home, end
		Added: Splore usage hint shown on empty favourites list
		Added: Warning on boot when data folder is read-only or can't be created
		Added: Pressing tab with code selected indents those lines (shift-tab to un-indent)
		Added: Double click word to select it
		Added: Trigger screenshot/video/label capture from inside program: extcmd()
		Changed: CTRL+left/right in code editor skips to end of word or span of non-whitespace
		Changed: When a cart terminates from splore, button press is required to continue
		Changed: load("@clip") can only be called from commandline (security)
		Fixed: Can over-allocate host memory if exceed it within one frame
		Fixed: atan2(-1, -32768) crash, and error for small values of dy
		Fixed: (Web) using cstore() on self causes unloadable cart (bug introduced in 0.1.8?)
		Fixed: (web) Pressing ctrl-v crashes the player (should do nothing)
		Fixed: (Raspberry Pi) WiringPi library required in static build
		Fixed: (Raspberry Pi) Crash on exit when launching via desktop icon
		Fixed: (Raspberry Pi) keyboard input broken (observed on raspi2s)


	v0.1.9b

		Added: Alternative function key mapping: ctrl-6..9 for F6..F9
		Added: Alternative glyph entry method: (ctrl-k) to toggle glyph mode
		Changed: Enter glyphs with shift a..z, but can be disabled in config.txt 
		Changed: Increased emscripten ram to 128MB (some carts at risk of running out)
		Fixed: Crash when window size is tiny or minified
		Fixed: Crash on toggling fullscreen mode
		Fixed: printh can write files outside filetree (security issue)
		Fixed: show_fps (can also now be toggled with ctrl-1)
		Fixed: Shorthand if/then syntax error when using the form: (functionname)(param)
		Fixed: log.txt not saved in path specified by -home switch
		Fixed: Default application data folder created even when -home specified
		Fixed: Missing dynamic builds (pico8_dyn) from linux archives
		Fixed: Removed unneeded RPATH from linux binaries
		Fixed: export foo%d.wav fails to write multiple files 

	v0.1.9
	
		Added: Copy and paste sprites and whole cartridges directly to BBS posts 
		Added: JAM category in splore
		Added: GPIO support for Raspberry Pi
		Added: Read clipboard using stat(4) after user presses CTRL-V
		Added: printh() can optionally write to a file or the host clipboard
		Added: Editor tool information and tips shown on mouseover
		Added: Set desktop path with -desktop (screenshots and gifs are saved here)
		Added: Warning on saving .p8 when compressed code size exceeds .p8.png limit
		Added: Alternative editor colours // config.txt: gui_theme 1
		Added: Dotted line every 8 rows in song view
		Added: -screenshot_scale (default: 3) and -gif_scale (default: 2)
		Added: Can use ctrl-up, ctrl-down to jump to start and end of code
		Added: CTRL-M to mute/unmute sound
		Added: HTML5-exported carts support 60fps
		Added: Timeout switch for splore downloads: -timeout
		Changed: Glyph characters typed with alt + a..z 
		Changed: stat(0) does not include allocations waiting to be garbage collected
		Changed: Unfiltered screen stretching at integer scales by default
		Changed: Removed -aspect and -scale settings (use draw_rect instead)
		Fixed: -home has no effect under Windows
		Fixed: Sometimes frame skipping starts before CPU usage has reached 100%
		Fixed: Double-speed BTNP() timing in 60fps mode
		Fixed: Exported HTML fails when _update60 is used instead of _update
		Fixed: Can't copy and paste button glyphs
		Fixed: Lines containing glyphs do not scroll far enough horizontally 
		Fixed: Loading .p8 renamed as .p8.png from splore freezes
		Fixed: Bucketfill in map doesn't sync to shared memory
		Fixed: fset fails when de-setting flags
		Fixed: Syntax error when beginning with the form: IF (..) [OR|AND]\n  
		Fixed: cls() costs twice as much cpu as it should
		Fixed: wav file exporter missing some data / writing truncated buffers
		Fixed: Entering new notes in song view doesn't observe current volume, instrument
		Fixed: alt-tab sometimes generates alt character text entry event
		Fixed: Resuming a cancelled download in splore causes crash
		Fixed: Controller attributes in log.txt always shown as -1	
		
		
	v0.1.8
	
		Added: 60fps support
		Added: Music exporter
		Added: Custom GIF length (maximum 120 seconds)
		Added: -,+ to navigate sprite tabs, sfx, music patterns
		Added: sfx editor: navigate with home, end, pageup/down, mousewheel
		Added: <, > to modify sfx speed, or click and drag
		Added: Middle mouse button to pan around spritesheet / map
		Added: Shortcut command for splore: S
		Added: Pre-installed selection of BBS cart (use INSTALL_GAMES)
		Added: Warning when saving .p8.png with no label 
		Added: (OSX) logging to ~/Library/Logs (viewable with Console.app)
		Added: -pixel_perfect switch (on by default)
		Added: -draw_rect switch
		Changed: Can not CTRL-S save over a loaded bbs cart
		Changed: Only .p8 files listed by dir() and by splore
		Changed: Command history increased to 256
		Changed: exit() / shutdown() have no effect while running cart
		Fixed: Memory usage (stat(0)) inconsistent across host platforms
		Fixed: Spinny disks shows when reloading current cart with load()
		Fixed: GIF saver does not respect 64x64 / mirrored modes
		Fixed: Miscellaneous multi-line comments / strings issues
		Fixed: Empty map cels cost cpu in mapdraw()
		Fixed: mapdraw() slowdown when drawing bottom half of map
		Fixed: preprocess changes semantics when += and : operators on same line
		Fixed: Identifiers starting with underscore counted as extra token
		Fixed: Saving .png exceeding compressed code limit fails silently
		Fixed: Right-clicking a sprite does not set the currently edited sprite
		Fixed: (Windows) extra space added to pasted lines
		Fixed: spr() expensive when drawn with low negative coordinates
		Fixed: pipe character identical to colon character
		Fixed: (Raspberry Pi) shift key appends a character when entering text
		Fixed: Editor mode buttons are still clickable during cart runtime
		Fixed: When loading a .p8.png file, label is reset and needs to be re-captured
		Fixed: export() does not report failure
		Fixed: mset()'d changes in shared memory not readable via peek() / sget()
		Fixed: cstore() saving edited code
		Fixed: audio pop between patterns during music playback

	v0.1.7
	
		Added: menuitem()
		Added: button glyphs in code (shift-L, R, U, D, X, O)
		Added: Customisable data directory (e.g. pico8 -home mydata)
		Added: Web gpio pins: read and write pico8_gpio[] in javscript 
		Fixed: SPLORE search doesn't reset
		Fixed: Splore skipping 33rd cart listing after loading more items
		Fixed: Crash when selecting a local binary file in splore
		Fixed: Semicolon can't be used as a list or statement separator 
		Fixed: Exported html can not cstore self


	v0.1.6

		Added: SPLORE local & bbs cartridge explorer
		Added: setmetatable(), cocreate(), coresume(), costatus(), yield()
		Added: Spinning cart icon to show when a cart is swapped / written to
		Added: Permanent storage when carts played in a browser
		Added: Adjustable aspect ratio (-aspect 420 for 1:1)
		Changed: Lua memory limit: 1024k (was 512k)
		Changed: Music channel now resumes after being clobbered by an sfx 
		Changed: Arpeggios double speed when SFX speed <= 8
		Changed: Exceeding compressed code limit does not block saving in .p8 format 
		Changed: spr() half as expensive, to be consistent with map()
		Changed: Fractional hex number notation: 0x0.3 == 0x0.3000, (was 0x0.0003)
		Changed: : operator doesn't count as an extra token (same as .)
		Changed: cstore() writes directly to disk
		Changed: cstore(), reload() return number of bytes read / written
		Changed: save() while running does nothing. (use cstore() instead)
		Changed: load() while running loads and runs the specified cartridge 
		Fixed: Small pops in audio mixer caused by sound wave discontinuities
		Fixed: HTML5-exported sound clicks badly under Chrome
		Fixed: Display palette is not oberserved when exporting GIFs
		Fixed: Rapid keypresses causes duplicate readings in tracker & text editor
		Fixed: += inside comments breaks preprocessor
		Fixed: sspr() cpu cost the same when clipped
		Fixed: cartdata() with bad parameters crashes
		Fixed: EXPORT from commandline can not be used without brackets and quotes
		

	v0.1.5
	
		Added: Raspberry Pi Build
		Added: Keyboard configuration for player buttons (KEYCONFIG) 
		Added: Music tracker select / copy / paste
		Added: Single-level undo in audio tools
		Added: Live preview of frequencies in sound editor
		Fixed: Command history extends past last reboot
		Fixed: Sfx exporter broken
		Fixed: Slashes at end of path resolve to double slashes
		Fixed: Load cart from commandline under Windows
		

	v0.1.4d
	v0.1.4c
	
		Fixed: International character entry inserting extra characters
		Fixed: Lines with tabs have broken cursor placement and display boundary

	v0.1.4b
	
		Fixed: OSX command-key combinations broken
		
	v0.1.4
		
		Added: spritesheet importing and exporting with import("blah.png"), export("blah.png")
		Added: sfx exporting with export("blah%d.wav")
		Added: External cartridge parameter for reload() and cstore()
		Added: Persistent cartridge data mapped to 0x5e00
		Added: Click token limit to toggle token & char limit display
		Added: assert(), type()
		Added: P to pause
		Changed: code char limit: 64k (was 32k)
		Changed: local declarations and semicolons not counted as tokens
		Changed: Pairs of brackets and block delimitations count as one token
		Changed: Only _update() or _draw() need to exist to enter main loop
		Changed: Allow forward-slash in code editor
		Changed: info() reports current (last loaded or saved) filename
		Changed: html5 version compiled with NO_DYNAMIC_EXECUTION 
		Changed: can only cstore up to 64 different files in one session
		Changed: load() automatically copies data section of cart to base ram
		Fixed: Shift-drag-copy sprites -> paste only pastes 1x1
		Fixed: ".." should count as one token
		Fixed: Tracker displaying D instead of .
		Fixed: Multi-line comments
		Fixed: Crash on run when code close to char limit
		Fixed: When over token limit, can not run any command
		Fixed: Unused high bits in SFX section not saved in .p8 format
		Fixed: Camera position memory mapping out of sync
		Fixed: pico8.txt link broken in windows installer
		Fixed: print() crashes when parameter is not a string or numbers
		Fixed: Multi-line strings & escape chars mess up tokenizer and print()
		Fixed: Joystick not responding when left stick is up to the left
		Fixed: Alt-F4 saves screenshot before quitting
		Fixed: Sprite editor mode button doesn't show fullscreen mode
		Fixed: -sound parameter not working in html5 version 
		
		
	v0.1.3
	
		Added: paste into commandline
		Fixed: lua standard libraries accessible
		Fixed: command-line loading doesn't work
		Fixed: music pattern finished too early when all tracks set to looping 
		Fixed: peek()ing odd bytes in sfx address space masks bit 7
		Fixed: cstore and reload from code space should have no effect
	
	v0.1.2
	
		Added: html5 cartridge exporter
		Added: Cartridge save data (64 fixed point numbers)
		Added: 8-player input
		Added: Demo carts: COLLIDE and BUTTERFLY
		Added: Command-line parameters // load cart, -run, settings
		Added: Alternative function keys (F6..F9 aliased as F1..F4)
		Added: pairs()
		Added: printh() for debugging
		Added: Tab completion for filenames in console
		Added: stack trace on runtime error
		Changed: music pattern length taken to be first non-looping channel's length
		Changed: noise instrument (6) has low frequency white noise scaled by volume
		Changed: screenshot captures whole window contents at display resolution
		Changed: del() moves remaining items up one index to maintain a packed table
		Changed: add(),del(),count(),all() no longer store extra fields
		Changed: removed count() from docs -- now just a legacy function. Use # operator instead.
		Changed: cursor only blinks while window is active
		Changed: peek(), poke() and bitwise operations (band()..) have no function call overhead
		Changed: yellow slightly warmer
		Changed: No camera snapping after pan in map mode
		Fixed: sqrt() crashing for 0 or >= 32761
		Fixed: Semi-colon characters in text editor
		Fixed: Long lines split when saving in .p8 format 
		Fixed: pget() does not respect camera position
		Fixed: Error message when peeking or poking outside of legal address space
		Fixed: Search replace colour fills one pixel outside of selected region
		Fixed: Playing an empty music pattern breaks subsequent music playback
		Fixed: Invalid sfx editing state on startup
		Fixed: Painting instruments values in frequency view also sets volumes
		Fixed: Inconsistent gif recording speeds
		Fixed: Unmapped joystick support
		Fixed: Compressed code size sometimes larger than uncompressed
		Fixed: mid() fails when first argument is not smallest
		Fixed: Scroll wheel changes sprite/map zoom while in code editor
		Fixed: CTRL-R (quick-run) drawing over current line in command mode
		Fixed: Label capture (F7) does not respect display palette state
		Fixed: Syntax highlighting of api functions and hex numbers
		Fixed: Looping to 0 with negative step finishes at 1
		Fixed: nil values printed as false instead of nil
		Fixed: Hexadecimal fractional parts
		Fixed: btnp() unresponsive when skipping frames
		Fixed: Editing mode is lost when using ctrl-r to run
		Fixed: Tracker note entry keys mapped, messing up piano-like layout
		Fixed: Shared gfx/map memory out of sync after some editor operations
		Fixed: Alt-gr character entry
		Fixed: Can map display palette to entries >= 16 using poke()
		Fixed: Using shift to select in code editor has wrong selection range
		Fixed: Dragging above top of text causes selection to flip to end
		Fixed: Duplicate at end of file listing
		
		
	v0.1.1

		Added: Token-based code limiting (8192 tokens, 32k ascii text)
		Added: Freeform move, pan and selection in sprite and map editors
		Added: Flood-fill tool (sprite and map)
		Added: .GIF saver
		Added: CTRL-Stamp to stamp with transparency
		Added: Single-step undo for map and sprites
		Added: 2x2 brush
		Added: sqrt(), atan2()
		Added: CTRL-S to quick-save
		Added: CTRL-R reloads .p8 file and runs (useful for external text editing)
		Added: Automatic backups on overwriting or quitting without saving
		Added: Scroll wheel zooms in sprite editor
		Added: Customisable resolution //  e.g. pico8 -width 580
		Added: Strings highlighted as green
		Added: ALT-click can optionally simulate right click (see config.txt)
		Added: palt() to control transparency for spr(), sspr()
		Added: info()
		Changed: load() tries adding .p8.png, .png if file doesn't exist
		Changed: Draw operations apply only to selection when active
		Changed: Move operations (cursors) apply to selection if present
		Changed: Removed time()
		Changed: Random seed is random on cart startup
		Changed: api functions never read directly from cart rom
		Changed: sspr() can take negative values for dw, dh
		Fixed: Sparse table indexing with integers fails
		Fixed: Assignment operators and shortform if-then-else failing
		Fixed: sspr() failed when w0 == 128
		Fixed: Circle drawing broken when camera not (0,0)
		Fixed: CPU hogging
		Fixed: Noise instrument clobbers rnd() sequence
		Fixed: Audio system not resetting on program reset
		Fixed: % operator sometimes wrong for negative values
		Fixed: Length operator (#)
		Fixed: Power operator (^)
		Fixed: Line clipping bug on right and bottom edges
		Fixed: print() precision for whole numbers
		Fixed: print() broken for negative y values
		Fixed: tokenization and keyword highlighting
		Fixed: sprite properties not copied/pasted
		Fixed: Only sfx 0..32 could be used as music patterns
		Fixed: Saving and loading a .p8 file adds newline to end of code
		Fixed: Drag selection to left margin in code editor -> selects all
		
		
	v0.1.0

		Added: demo cart: hello.p8 (use install_demos)
		Added: CTRL-R from anywhere to run cart or restart cart
		Added: use a,s to select colour in gfx editor
		Added: consistent operation cpu costs
		Added: btn(), btnp() with no arguments returns bitfield
		Added: fget(id) returns bitfield of that sprite's flags
		Changed: renamed mapdraw() to map() for consistency
		Changed: default sleep time is 5ms (better cpu consumption for laptops)
		Fixed: memory limiter
		Fixed: wonky line and circle drawing
		Fixed: shift-click volume in sfx editor to set all
		Fixed: number formatting is now never in scientific notation
		Fixed: clipped error messages in console
		Fixed: text undo stores rollback points when chaning line number
		Fixed: print(str) carriage returns to previous x


	v0.0.5

		Added: help()
		Added: Ctrl+F / Ctrl+G to search for text, repeat search
		Added: del key in code editor
		Added: Short-hand single-line IF statements
		Added: Unary operators += -= /= *= %=
		Added: srand(), time(), added rnd() to docs
		Added: Ctrl+D to duplicate line
		Added: interactive ls() for multi-page file listings
		Added: band() bor() bxor() bnot() shl() shr()
		Added: runtime error line number
		Added: dir() (aliased to ls())
		Changed: print() only autoscrolls when called with no parameters
		Changed: alt+up/down to skip between function definitions (was ctrl)
		Changed: sspr() dw, dh defaults to sw, sh
		Fixed: Load crashes on files that are not .p8 format or directories
		Fixed: Misc editor cursor position glitches
		Fixed: Crash when syntax error occurs before viewing code
		Fixed: Broken newlines after rebooting
		Fixed: mkdir() called with no parameters creating "(null)" directory
		Fixed: scrolling past top of code with scrollwheel
		Fixed: alt-f4 to fastquit


	v0.0.4

		Added: Jelpi demo cart
		Added: Internal carts // use install_demos()
		Added: Joystick support
		Added: Undo/redo in code editor
		Added: Scroll wheel in code editor
		Added: LCTRL + UP/DOWN to navigate functions in code editor
		Added: LALT + LEFT/RIGHT to switch editing modes
		Added: btnp()
		Added: Release looping sample (a in editor , sfx(-2, channel) in code)
		Changed: Music stops when pausing program execution
		Changed: Allow 8 settable sprite flags
		Changed: Made noise instrument more bassy
		Fixed: Home, end keys
		Fixed: Sprite flags 4,5 not saved
		Fixed: mset() discarding 4 high bits
		Fixed: Crash when highlighting long strings


	v0.0.3

		Added: Palette mapping type 1 (on display)
		Added: Collections can be initialized with c={1,2,..}
		Added: holdframe() // used automatically by _draw(), update()
		Added: Sprite selections and operations across selections
		Added: Map selection and stamp tool
		Added: Immediate mode screen buffer preserved while switching views
		Added: Channel mask for music playback
		Added: Memory mapping for live sound data
		Added: .png cart format
		Added: Sprite navigation by keyboard (-, +)
		Fixed: Strict 4-channel sound
		Fixed: Automatic sfx channel selection (channel index: -1)


	v0.0.2

		Added: Command history
		Added: P2 keys
		Added: Boot sequence
		Added: Windows, 64-bit linux builds
		Added: CPU cost of internal api functions
		Added: Separate song channel index and mute status
		Added: Memory mapping
		Added: Search/replace colour in sprite editor
		Added: Copy/paste sprites and map regions
		Improved: Immediate mode command editing
		Improved: Editor cursor behaviour
		Fixed: Automatic audio channel selection


	v0.0.1 

		First Alpha



