open_toontown_panda3d/panda/src/tinydisplay/vertex.cxx

85 lines
2.7 KiB
C++

#include "zgl.h"
#include "string.h"
void gl_eval_viewport(GLContext * c) {
GLViewport *v = &c->viewport;
GLScissor *s = &c->scissor;
float xsize = v->xsize * (s->right - s->left);
float xmin = v->xmin + v->xsize * s->left;
float ysize = v->ysize * (s->top - s->bottom);
float ymin = v->ymin + v->ysize * (1.0f - s->top);
float zsize = (1 << (ZB_Z_BITS + ZB_POINT_Z_FRAC_BITS));
v->trans.X = ((xsize - 0.5f) / 2.0f) + xmin;
v->trans.Y = ((ysize - 0.5f) / 2.0f) + ymin;
v->trans.Z = ((zsize - 0.5f) / 2.0f) + ((1 << ZB_POINT_Z_FRAC_BITS)) / 2;
v->scale.X = (xsize - 0.5f) / 2.0f;
v->scale.Y = -(ysize - 0.5f) / 2.0f;
v->scale.Z = -((zsize - 0.5f) / 2.0f);
}
/* coords, tranformation , clip code and projection */
/* TODO : handle all cases */
void gl_vertex_transform(GLContext * c, GLVertex * v)
{
float *m;
V4 *n;
if (c->lighting_enabled) {
/* eye coordinates needed for lighting */
m = &c->matrix_model_view.m[0][0];
v->ec.X = (v->coord.X * m[0] + v->coord.Y * m[1] +
v->coord.Z * m[2] + m[3]);
v->ec.Y = (v->coord.X * m[4] + v->coord.Y * m[5] +
v->coord.Z * m[6] + m[7]);
v->ec.Z = (v->coord.X * m[8] + v->coord.Y * m[9] +
v->coord.Z * m[10] + m[11]);
v->ec.W = (v->coord.X * m[12] + v->coord.Y * m[13] +
v->coord.Z * m[14] + m[15]);
/* projection coordinates */
m = &c->matrix_projection.m[0][0];
v->pc.X = (v->ec.X * m[0] + v->ec.Y * m[1] +
v->ec.Z * m[2] + v->ec.W * m[3]);
v->pc.Y = (v->ec.X * m[4] + v->ec.Y * m[5] +
v->ec.Z * m[6] + v->ec.W * m[7]);
v->pc.Z = (v->ec.X * m[8] + v->ec.Y * m[9] +
v->ec.Z * m[10] + v->ec.W * m[11]);
v->pc.W = (v->ec.X * m[12] + v->ec.Y * m[13] +
v->ec.Z * m[14] + v->ec.W * m[15]);
m = &c->matrix_model_view_inv.m[0][0];
n = &c->current_normal;
v->normal.X = (n->X * m[0] + n->Y * m[1] + n->Z * m[2]) * c->normal_scale;
v->normal.Y = (n->X * m[4] + n->Y * m[5] + n->Z * m[6]) * c->normal_scale;
v->normal.Z = (n->X * m[8] + n->Y * m[9] + n->Z * m[10]) * c->normal_scale;
if (c->normalize_enabled) {
gl_V3_Norm(&v->normal);
}
} else {
/* no eye coordinates needed, no normal */
/* NOTE: W = 1 is assumed */
m = &c->matrix_model_projection.m[0][0];
v->pc.X = (v->coord.X * m[0] + v->coord.Y * m[1] +
v->coord.Z * m[2] + m[3]);
v->pc.Y = (v->coord.X * m[4] + v->coord.Y * m[5] +
v->coord.Z * m[6] + m[7]);
v->pc.Z = (v->coord.X * m[8] + v->coord.Y * m[9] +
v->coord.Z * m[10] + m[11]);
if (c->matrix_model_projection_no_w_transform) {
v->pc.W = m[15];
} else {
v->pc.W = (v->coord.X * m[12] + v->coord.Y * m[13] +
v->coord.Z * m[14] + m[15]);
}
}
v->clip_code = gl_clipcode(v->pc.X, v->pc.Y, v->pc.Z, v->pc.W);
}