papermario/src/os/perspective.c

47 lines
1.1 KiB
C

#include "PR/guint.h"
f32 sin_rad(f32 x);
f32 cos_rad(f32 x);
void guPerspectiveF(f32 mf[4][4], u16 *perspNorm, f32 fovy, f32 aspect, f32 near, f32 far, f32 scale) {
f32 cot;
s32 i, j;
guMtxIdentF(mf);
fovy *= 3.1415926 / 180.0;
cot = cos_rad(fovy/2) / sin_rad(fovy/2);
mf[0][0] = cot / aspect;
mf[1][1] = cot;
mf[2][2] = (near + far) / (near - far);
mf[2][3] = -1;
mf[3][2] = (2 * near * far) / (near - far);
mf[3][3] = 0;
for (i = 0; i < 4; i++) {
for (j = 0; j < 4; j++) {
mf[i][j] *= scale;
}
}
if (perspNorm != (u16 *) NULL) {
if (near + far <= 2.0) {
*perspNorm = (u16) 0xFFFF;
} else {
*perspNorm = (u16) ((2.0 * 65536.0) / (near + far));
if (*perspNorm <= 0) {
*perspNorm = (u16) 0x0001;
}
}
}
}
void guPerspective(Mtx *m, u16 *perspNorm, f32 fovy, f32 aspect, f32 near, f32 far, f32 scale) {
f32 mf[4][4];
guPerspectiveF(mf, perspNorm, fovy, aspect, near, far, scale);
guMtxF2L(mf, m);
}