ref: ebb784911c15f0a5b7ed1d61be7052a5b476f8e7
dir: /src/vertex.c/
#include "zgl.h"
#include <string.h>
void glopNormal(GLParam* p) {
V3 v;
GLContext* c = gl_get_context();
v.X = p[1].f;
v.Y = p[2].f;
v.Z = p[3].f;
c->current_normal.X = v.X;
c->current_normal.Y = v.Y;
c->current_normal.Z = v.Z;
c->current_normal.W = 0;
}
void glopTexCoord(GLParam* p) {
GLContext* c = gl_get_context();
c->current_tex_coord.X = p[1].f;
c->current_tex_coord.Y = p[2].f;
c->current_tex_coord.Z = p[3].f;
c->current_tex_coord.W = p[4].f;
}
void glopEdgeFlag(GLParam* p) {
GLContext* c = gl_get_context();
c->current_edge_flag = p[1].i;
}
void glopColor(GLParam* p) {
GLContext* c = gl_get_context();
c->current_color.X = p[1].f;
c->current_color.Y = p[2].f;
c->current_color.Z = p[3].f;
c->current_color.W = p[4].f;
if (c->color_material_enabled) {
GLParam q[7];
q[0].op = OP_Material;
q[1].i = c->current_color_material_mode;
q[2].i = c->current_color_material_type;
q[3].f = p[1].f;
q[4].f = p[2].f;
q[5].f = p[3].f;
q[6].f = p[4].f;
glopMaterial(q);
}
}
void glopBegin(GLParam* p) {
GLint type;
M4 tmp;
GLContext* c = gl_get_context();
#if TGL_FEATURE_ERROR_CHECK == 1
if (c->in_begin != 0)
#define ERROR_FLAG GL_INVALID_OPERATION
#include "error_check.h"
#else
#endif
type = p[1].i;
c->begin_type = type;
c->in_begin = 1;
c->vertex_n = 0;
c->vertex_cnt = 0;
if (c->matrix_model_projection_updated) {
if (c->lighting_enabled) {
/* precompute inverse modelview */
gl_M4_Inv(&tmp, c->matrix_stack_ptr[0]);
gl_M4_Transpose(&c->matrix_model_view_inv, &tmp);
} else {
GLfloat* m = &c->matrix_model_projection.m[0][0];
/* precompute projection matrix */
gl_M4_Mul(&c->matrix_model_projection, c->matrix_stack_ptr[1], c->matrix_stack_ptr[0]);
/* test to accelerate computation */
c->matrix_model_projection_no_w_transform = 0;
if (m[12] == 0.0 && m[13] == 0.0 && m[14] == 0.0)
/*
if(c->matrix_model_projection.m[3][0] == 0.0 &&
c->matrix_model_projection.m[3][1] == 0.0 &&
c->matrix_model_projection.m[3][2] == 0.0)
*/
c->matrix_model_projection_no_w_transform = 1;
}
/* test if the texture matrix is not Identity */
c->apply_texture_matrix = !gl_M4_IsId(c->matrix_stack_ptr[2]);
c->matrix_model_projection_updated = 0;
}
/* viewport- this is now updated on a glViewport call.
if (c->viewport.updated) {
gl_eval_viewport(c);
c->viewport.updated = 0;
}
triangle drawing functions
*/
#if TGL_FEATURE_ALT_RENDERMODES == 1
if (c->render_mode == GL_SELECT) {
c->draw_triangle_front = gl_draw_triangle_select;
c->draw_triangle_back = gl_draw_triangle_select;
} else if (c->render_mode == GL_FEEDBACK) {
c->draw_triangle_front = gl_draw_triangle_feedback;
c->draw_triangle_back = gl_draw_triangle_feedback;
} else
#endif
{
switch (c->polygon_mode_front) {
case GL_POINT:
c->draw_triangle_front = gl_draw_triangle_point;
break;
case GL_LINE:
c->draw_triangle_front = gl_draw_triangle_line;
break;
default:
c->draw_triangle_front = gl_draw_triangle_fill;
break;
}
switch (c->polygon_mode_back) {
case GL_POINT:
c->draw_triangle_back = gl_draw_triangle_point;
break;
case GL_LINE:
c->draw_triangle_back = gl_draw_triangle_line;
break;
default:
c->draw_triangle_back = gl_draw_triangle_fill;
break;
}
}
}
static void gl_transform_to_viewport_vertex_c(GLVertex* v) {
GLContext* c = gl_get_context();
{
GLfloat winv = 1.0 / v->pc.W;
v->zp.x = (GLint)(v->pc.X * winv * c->viewport.scale.X + c->viewport.trans.X);
v->zp.y = (GLint)(v->pc.Y * winv * c->viewport.scale.Y + c->viewport.trans.Y);
v->zp.z = (GLint)(v->pc.Z * winv * c->viewport.scale.Z + c->viewport.trans.Z);
}
v->zp.r = (GLint)(v->color.v[0] * COLOR_CORRECTED_MULT_MASK + COLOR_MIN_MULT) & COLOR_MASK;
v->zp.g = (GLint)(v->color.v[1] * COLOR_CORRECTED_MULT_MASK + COLOR_MIN_MULT) & COLOR_MASK;
v->zp.b = (GLint)(v->color.v[2] * COLOR_CORRECTED_MULT_MASK + COLOR_MIN_MULT) & COLOR_MASK;
if (c->texture_2d_enabled) {
v->zp.s = (GLint)(v->tex_coord.X * (ZB_POINT_S_MAX - ZB_POINT_S_MIN) + ZB_POINT_S_MIN);
v->zp.t = (GLint)(v->tex_coord.Y * (ZB_POINT_T_MAX - ZB_POINT_T_MIN) + ZB_POINT_T_MIN);
}
}
static void gl_vertex_transform(GLVertex* v) {
GLfloat* m;
GLContext* c = gl_get_context();
if (c->lighting_enabled)
{
/* eye coordinates needed for lighting */
V4* n;
m = &c->matrix_stack_ptr[0]->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_stack_ptr[1]->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]);
v->normal.Y = (n->X * m[4] + n->Y * m[5] + n->Z * m[6]);
v->normal.Z = (n->X * m[8] + n->Y * m[9] + n->Z * m[10]);
if (c->normalize_enabled) {
gl_V3_Norm_Fast(&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);
}
void glopVertex(GLParam* p) {
GLVertex* v;
GLint n, i, cnt;
GLContext* c = gl_get_context();
#if TGL_FEATURE_ERROR_CHECK == 1
if (c->in_begin == 0)
#define ERROR_FLAG GL_INVALID_OPERATION
#include "error_check.h"
#else
#endif
n = c->vertex_n;
cnt = c->vertex_cnt;
cnt++;
c->vertex_cnt = cnt;
/* new vertex entry */
v = &c->vertex[n];
n++;
v->coord.X = p[1].f;
v->coord.Y = p[2].f;
v->coord.Z = p[3].f;
v->coord.W = p[4].f;
gl_vertex_transform(v);
/* color */
if (c->lighting_enabled) {
gl_shade_vertex(v);
#include "error_check.h"
} else {
v->color = c->current_color;
}
/* tex coords */
#if TGL_OPTIMIZATION_HINT_BRANCH_COST < 1
if (c->texture_2d_enabled)
#endif
{
if (c->apply_texture_matrix) {
gl_M4_MulV4(&v->tex_coord, c->matrix_stack_ptr[2], &c->current_tex_coord);
} else {
v->tex_coord = c->current_tex_coord;
}
}
/* precompute the mapping to the viewport */
#if TGL_OPTIMIZATION_HINT_BRANCH_COST < 2
if (v->clip_code == 0)
#endif
{
gl_transform_to_viewport_vertex_c(v);
}
/* edge flag */
v->edge_flag = c->current_edge_flag;
switch (c->begin_type) {
case GL_POINTS:
gl_draw_point(&c->vertex[0]);
n = 0;
break;
case GL_LINES:
if (n == 2) {
gl_draw_line(&c->vertex[0], &c->vertex[1]);
n = 0;
}
break;
case GL_LINE_STRIP:
#if TGL_FEATURE_GL_POLYGON == 1
case GL_LINE_LOOP:
#endif
switch (n) {
case 1: {
c->vertex[2] = c->vertex[0];
} break;
case 2: {
gl_draw_line(&c->vertex[0], &c->vertex[1]);
c->vertex[0] = c->vertex[1];
n = 1;
} break;
default:
break;
};
break;
case GL_TRIANGLES:
if (n == 3) {
gl_draw_triangle(&c->vertex[0], &c->vertex[1], &c->vertex[2]);
n = 0;
}
break;
case GL_TRIANGLE_STRIP:
if (cnt >= 3) {
if (n == 3)
n = 0;
/* needed to respect triangle orientation */
switch (cnt & 1) {
case 0:
gl_draw_triangle(&c->vertex[2], &c->vertex[1], &c->vertex[0]);
break;
default:
case 1:
gl_draw_triangle(&c->vertex[0], &c->vertex[1], &c->vertex[2]);
break;
}
}
break;
case GL_TRIANGLE_FAN:
if (n == 3) {
gl_draw_triangle(&c->vertex[0], &c->vertex[1], &c->vertex[2]);
c->vertex[1] = c->vertex[2];
n = 2;
}
break;
case GL_QUADS:
if (n == 4) {
c->vertex[2].edge_flag = 0;
gl_draw_triangle(&c->vertex[0], &c->vertex[1], &c->vertex[2]);
c->vertex[2].edge_flag = 1;
c->vertex[0].edge_flag = 0;
gl_draw_triangle(&c->vertex[0], &c->vertex[2], &c->vertex[3]);
n = 0;
}
break;
case GL_QUAD_STRIP:
if (n == 4) {
gl_draw_triangle(&c->vertex[0], &c->vertex[1], &c->vertex[2]);
gl_draw_triangle(&c->vertex[1], &c->vertex[3], &c->vertex[2]);
for (i = 0; i < 2; i++)
c->vertex[i] = c->vertex[i + 2];
n = 2;
}
break;
#if TGL_FEATURE_GL_POLYGON == 1
case GL_POLYGON:
break;
#endif
#if TGL_FEATURE_ERROR_CHECK == 1
default:
gl_fatal_error("glBegin: type %x not handled\n", c->begin_type);
#else
default:
break;
#endif
}
c->vertex_n = n;
}
void glopEnd(GLParam* param) {
GLContext* c = gl_get_context();
#if TGL_FEATURE_ERROR_CHECK == 1
if (c->in_begin != 1)
#define ERROR_FLAG GL_INVALID_OPERATION
#include "error_check.h"
#else
/* Assume it went alright.*/
#endif
#if TGL_FEATURE_GL_POLYGON == 1
if (c->begin_type == GL_LINE_LOOP) {
if (c->vertex_cnt >= 3) {
gl_draw_line(&c->vertex[0], &c->vertex[2]);
}
} else if (c->begin_type == GL_POLYGON) {
GLint i = c->vertex_cnt;
while (i >= 3) {
i--;
gl_draw_triangle(&c->vertex[i], &c->vertex[0], &c->vertex[i - 1]);
}
}
#endif
c->in_begin = 0;
}