#include <revolution/mtx.h>
void MTXLightOrtho(
Mtx m,
f32 t,
f32 b,
f32 l,
f32 r,
f32 scaleS,
f32 scaleT,
f32 transS,
f32 transT );
m |
New 3x4 parallel projection matrix. m may be either an Mtx or an MtxPtr.. |
t |
Top edge of view volume. |
b |
Bottom edge of view volume. |
l |
Left edge of view volume. |
r |
Right edge of view volume. |
scaleS |
Scale in the S direction for projected coordinates (usually 0.5). |
scaleT |
Scale in the T direction for projected coordinates (usually 0.5). |
transS |
Translate in the S direction for projected coordinates (usually 0.5). |
transT |
Translate in the T direction for projected coordinates (usually 0.5). |
None.
Sets a 3x4 matrix for orthographic projection. This matrix is used to project points into texture space and yield texture coordinates.
For normal parallel projections, the axis of projection is the -z axis, so t = positive, b = -t, r = positive, l = -r.
Standard projection yields values ranging from -1.0 to 1.0 in both dimensions of the front clipping plane. Since texture coordinates should usually be within the range of 0.0 to 1.0, we have added a scale and translation value for both S and T. The most common way to use these values is to set all of them to 0.5 (so that points in the range of -1.0 to 1.0 are first scaled by 0.5) to be in the range of -0.5 to 0.5. Then they are translated by 0.5 to be in the range of 0.0 to 1.0. Other values can be used for translation and scale to yield different effects.
Mtx, MtxPtr, MTXLightFrustum, MTXLightPerspective
03/01/2006 Initial version.