/*---------------------------------------------------------------------------*
  Project:  TWL-System - demos - g3d - samples - Translucent
  File:     main.c

  Copyright 2004-2009 Nintendo.  All rights reserved.

  These coded instructions, statements, and computer programs contain
  proprietary information of Nintendo of America Inc. and/or Nintendo
  Company Ltd., and are protected by Federal copyright law.  They may
  not be disclosed to third parties or copied or duplicated in any form,
  in whole or in part, without the prior written consent of Nintendo.

  $Revision: 1155 $
 *---------------------------------------------------------------------------*/

//---------------------------------------------------------------------------
//
// Sample that renders objects using translucent polygons.
//
// It is possible to specify the order of output to the geometry engine by editing the priority attribute of the <display> element.
// 
// In addition, be sure to read the HOWTO below, as there are several points to keep in mind when it comes to coding and creating data when rendering models that include translucent polygons.
// 
//
// Sample Operation
// Two groups of squares are arranged on the left and right. From background to foreground, they are layered in the order blue -> green -> red.
// The blue squares are opaque and the red and green squares are translucent. From the right of the screen, the green and red squares are rendered in the order of green->red. On the left, they are rendered in red->green order.
// Suitable rendering results can be obtained for the group of objects on the right side by rendering from the deepest screen layer up (from the camera's position at runtime).
// 
//
// HOWTO:
// 1: When translucent materials overlap each other, be sure to give them different polygon IDs.
//    Due to hardware specifications, translucent pixels are not overwritten if the same polygon ID is used.
//    
// 2: Edit the priority attribute of the <display> element so that the overlapping translucent polygons are rendered from (as viewed from the camera's position) the back forward.
//    
// 3: Note that the first argument to G3_SwapBuffers must be GX_SORTMODE_MANUAL.
//    
// 
//---------------------------------------------------------------------------

#include "g3d_demolib.h"

G3DDemoCamera gCamera;        // Camera structure.
G3DDemoGround gGround;        // Ground structure.

static void          InitG3DLib(void);
static NNSG3dResMdl* LoadG3DModel(const char* path);
static void          SetCamera(G3DDemoCamera* camera);


/* -------------------------------------------------------------------------
  Name:         NitroMain

  Description:  Sample main.

  Arguments:    None.

  Returns:      None.
   ------------------------------------------------------------------------- */
void
NitroMain(void)
{
    NNSG3dRenderObj object;
    NNSG3dResMdl*   pModel;
    NNSFndAllocator allocator;

    G3DDemo_InitSystem();
    G3DDemo_InitMemory();
    G3DDemo_InitVRAM();

    InitG3DLib();
    G3DDemo_InitDisplay();

    //
    // Create allocator with 4-byte alignment
    //
    NNS_FndInitAllocatorForExpHeap(&allocator, G3DDemo_AppHeap, 4);

    // Make the manager able to manage 4 slots'-worth of texture image slots, and set it as the default manager.
    // 
    NNS_GfdInitFrmTexVramManager(4, TRUE);

    // Make the manager able to manage 32 KB of palettes, and set it as the default manager.
    // 
    NNS_GfdInitFrmPlttVramManager(0x8000, TRUE);

    pModel = LoadG3DModel("data/priority_check.nsbmd");
    SDK_ASSERTMSG(pModel, "load failed");

    //
    // G3D: NNSG3dRenderObj initialization
    //
    // NNSG3dRenderObj is a structure that holds a single model, and every type of information related to the animations applied to that model.
    // 
    // The area specified by the internal member pointer must be obtained and released by the user.
    // Here mdl can be NULL. (But it must be set to a value, not NULL, during NNS_G3dDraw.)
    //
    NNS_G3dRenderObjInit(&object, pModel);
    
    //
    // Demo Common Initialization
    //
    G3DDemo_InitCamera(&gCamera, 0*FX32_ONE, 4*FX32_ONE);
    G3DDemo_InitGround(&gGround, (fx32)(1.5*FX32_ONE));

    G3DDemo_InitConsole();
    G3DDemo_Print(0,0, G3DDEMO_COLOR_YELLOW, "Translucent");

    for(;;)
    {
        OSTick time;

        SVC_WaitVBlankIntr();

        G3DDemo_PrintApplyToHW();
        G3DDemo_ReadGamePad();

        G3DDemo_MoveCamera(&gCamera);
        G3DDemo_CalcCamera(&gCamera);

        G3X_Reset();
        G3X_ResetMtxStack();

        SetCamera(&gCamera);

        {
            //
            // G3D:
            // Collects and transfers the states set with G3dGlbXXXX.
            // Camera and projection matrix, and the like, are set.
            //
            NNS_G3dGlbFlushP();

            //  Start measuring the time
            time = OS_GetTick();
            {
                //
                // G3D: NNS_G3dDraw
                // Passing the configured NNSG3dRenderObj structure can perform rendering in any situation.
                // 
                //
                NNS_G3dDraw(&object);
            }
            // Time measurement result
            time = OS_GetTick() - time;
        }

        {
            //
            // G3D: Normally, when any of the G3_XXX functions are called, you have to call the NNS_G3dGeComFlushBuffer() function before that and synchronize.
            //      
            //
            NNS_G3dGlbFlushP();
            NNS_G3dGeFlushBuffer();
            G3DDemo_DrawGround(&gGround);
        }

        //
        // NOTICE:
        // To display translucent polygons, GX_SORTMODE_MANUAL must be specified.
        //
        G3_SwapBuffers(GX_SORTMODE_MANUAL, GX_BUFFERMODE_W); /* Swap memory relating to geometry and rendering engine */

        G3DDemo_Printf(16,0, G3DDEMO_COLOR_YELLOW, "TIME:%06ld usec", OS_TicksToMicroSeconds(time));
    }
}


/* -------------------------------------------------------------------------
  Name:         InitG3DLib

  Description:  Initializes G3D library.

  Arguments:    None.

  Returns:      None.
   ------------------------------------------------------------------------- */
static void
InitG3DLib(void)
{
    //
    // G3D:
    // Performs default initialization.
    // ------------------------------------------------------------------------
    NNS_G3dInit();
}


/* -------------------------------------------------------------------------
  Name:         LoadG3DModel

  Description:  Loads model data from file.

  Arguments:    path: Model data path name.

  Returns:      Pointer to model.
   ------------------------------------------------------------------------- */
static NNSG3dResMdl*
LoadG3DModel(const char* path)
{
    NNSG3dResMdl*        model   = NULL;
    NNSG3dResTex*        texture = NULL;
    NNSG3dResFileHeader* resFile = G3DDemo_LoadFile(path);
    BOOL status;

    SDK_NULL_ASSERT(resFile);

    // To use DMA transfers within functions like NNS_G3dResDefaultSetup and NNS_G3dDraw, all model resources have to be stored in memory before calling those functions.
    // 
    // After a certain size, for large resources it is faster to just call DC_StoreAll.
    // For information on DC_StoreRange and DC_StoreAll, refer to the NITRO-SDK Function Reference Manual.
    DC_StoreRange(resFile, resFile->fileSize);

    status = NNS_G3dResDefaultSetup(resFile);
    NNS_G3D_ASSERTMSG(status, "NNS_G3dResDefaultSetup failed");

    //
    // G3D: Gets model
    // Since nsbmd can include multiple models, gets the pointer to a single model by specifying its index. When there is only one model, use 0.
    // 
    // --------------------------------------------------------------------
    model = NNS_G3dGetMdlByIdx(NNS_G3dGetMdlSet(resFile), 0);

    return model;
}


/* -------------------------------------------------------------------------
  Name:         SetCamera

  Description:  Sets camera matrix and projection matrix in G3D global state.

  Arguments:    camera:		Pointer to the G3DDemoCamera structure.

  Returns:      None.
   ------------------------------------------------------------------------- */
static void
SetCamera(G3DDemoCamera* camera)
{
    G3DDemoLookAt* lookat = &camera->lookat;
    G3DDemoPersp*  persp  = &camera->persp;

    NNS_G3dGlbPerspective(persp->fovySin, persp->fovyCos, persp->aspect, persp->nearClip, persp->farClip);
    NNS_G3dGlbLookAt(&lookat->camPos, &lookat->camUp, &lookat->target);
}
