# G3_OrthoW

## C Specification

      #include <nitro/gx/g3_util.h>

      void G3_OrthoW(
      fx32 t,
      fx32 b,
      fx32 l,
      fx32 r,
      fx32 n,
      fx32 f,
      fx32 scaleW,
      MtxFx44 * mtx
      );

## Arguments

t | Y coordinate at the top of the near clipping plane
`b` | Y coordinate at the bottom of the near clipping plane
l | X coordinate at the left of the near clipping plane
r | X coordinate at the right of the near clipping plane
n | Distance from eyepoint to the `near` clip plane
f | Distance from eyepoint to the `far` clip plane
scaleW | Fine adjustment parameter for the view volume
mtx | The pointer to a 4x4 matrix.

## Return Values

None.

## Description

This function sets the Matrix mode to the Projection mode. This function also sets the Orthogonal Projection matrix as the current matrix. If `mtx` is not `NULL`, then the Orthogonal Projection matrix is also set in *`mtx`. This function uses the Divider. The diagram shows the matrix that is set.

Note: When setting the matrix for an orthogonal projection, it will be necessary to select Z-buffering with the `G3*_SwapBuffers`. The operation is not guaranteed if W-buffering is used, since the depth value is constant.

×scaleW

## See Also

`G3_Ortho, G3_FrustumW,G3_PerspectiveW`

## Revision History

04/27/2004 Initial version

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