7 #define CLIP_XMIN (1<<0)
8 #define CLIP_XMAX (1<<1)
9 #define CLIP_YMIN (1<<2)
10 #define CLIP_YMAX (1<<3)
11 #define CLIP_ZMIN (1<<4)
12 #define CLIP_ZMAX (1<<5)
19 winv = 1.0f / v->pc.v[3];
20 v->zp.x= (int) ( v->pc.v[0] * winv * c->viewport.scale.v[0]
21 + c->viewport.trans.v[0] );
22 v->zp.y= (int) ( v->pc.v[1] * winv * c->viewport.scale.v[1]
23 + c->viewport.trans.v[1] );
24 v->zp.z= (int) ( v->pc.v[2] * winv * c->viewport.scale.v[2]
25 + c->viewport.trans.v[2] );
28 int z = v->zp.z + (c->zbias << (ZB_POINT_Z_FRAC_BITS + 4));
29 if (z < v->zp.z && c->zbias > 0) {
31 }
else if (z > v->zp.z && c->zbias < 0) {
38 static const int z_range = (1 << (ZB_Z_BITS + ZB_POINT_Z_FRAC_BITS)) - 1;
39 double z = 1.0 - (double)(v->zp.z) / (double)(z_range);
40 z = z * c->zrange + c->zmin;
41 v->zp.z = (int)((1.0 - z) * (double)(z_range)) + 1;
45 v->zp.r=min((
int)(v->color.v[0] * (ZB_POINT_RED_MAX - ZB_POINT_RED_MIN))
46 + ZB_POINT_RED_MIN, ZB_POINT_RED_MAX);
47 v->zp.g=min((
int)(v->color.v[1] * (ZB_POINT_GREEN_MAX - ZB_POINT_GREEN_MIN))
48 + ZB_POINT_GREEN_MIN, ZB_POINT_GREEN_MAX);
49 v->zp.b=min((
int)(v->color.v[2] * (ZB_POINT_BLUE_MAX - ZB_POINT_BLUE_MIN))
50 + ZB_POINT_BLUE_MIN, ZB_POINT_BLUE_MAX);
51 v->zp.a=min((
int)(v->color.v[3] * (ZB_POINT_ALPHA_MAX - ZB_POINT_ALPHA_MIN))
52 + ZB_POINT_ALPHA_MIN, ZB_POINT_ALPHA_MAX);
55 if (c->num_textures_enabled >= 1) {
56 static const int si = 0;
57 v->zp.s = (int)(v->tex_coord[si].v[0] * c->current_textures[si]->s_max);
58 v->zp.t = (int)(v->tex_coord[si].v[1] * c->current_textures[si]->t_max);
60 if (c->num_textures_enabled >= 2) {
61 static const int si = 1;
62 v->zp.sa = (int)(v->tex_coord[si].v[0] * c->current_textures[si]->s_max);
63 v->zp.ta = (int)(v->tex_coord[si].v[1] * c->current_textures[si]->t_max);
65 if (c->num_textures_enabled >= 3) {
66 static const int si = 2;
67 v->zp.sb = (int)(v->tex_coord[si].v[0] * c->current_textures[si]->s_max);
68 v->zp.tb = (int)(v->tex_coord[si].v[1] * c->current_textures[si]->t_max);
77 if (p0->clip_code == 0) {
78 ZB_plot(c->zb,&p0->zp);
86 q->pc.v[0]=p0->pc.v[0]+(p1->pc.v[0]-p0->pc.v[0])*t;
87 q->pc.v[1]=p0->pc.v[1]+(p1->pc.v[1]-p0->pc.v[1])*t;
88 q->pc.v[2]=p0->pc.v[2]+(p1->pc.v[2]-p0->pc.v[2])*t;
89 q->pc.v[3]=p0->pc.v[3]+(p1->pc.v[3]-p0->pc.v[3])*t;
91 q->color.v[0]=p0->color.v[0] + (p1->color.v[0]-p0->color.v[0])*t;
92 q->color.v[1]=p0->color.v[1] + (p1->color.v[1]-p0->color.v[1])*t;
93 q->color.v[2]=p0->color.v[2] + (p1->color.v[2]-p0->color.v[2])*t;
94 q->color.v[3]=p0->color.v[3] + (p1->color.v[3]-p0->color.v[3])*t;
103 static inline int ClipLine1(PN_stdfloat denom,PN_stdfloat num,PN_stdfloat *tmin,PN_stdfloat *tmax)
109 if (t>*tmax)
return 0;
110 if (t>*tmin) *tmin=t;
111 }
else if (denom<0) {
113 if (t<*tmin)
return 0;
114 if (t<*tmax) *tmax=t;
115 }
else if (num>0)
return 0;
121 PN_stdfloat dx,dy,dz,dw,x1,y1,z1,w1;
122 PN_stdfloat tmin,tmax;
129 if ( (cc1 | cc2) == 0) {
131 ZB_line_z(c->zb,&p1->zp,&p2->zp);
133 ZB_line(c->zb,&p1->zp,&p2->zp);
134 }
else if ( (cc1&cc2) != 0 ) {
137 dx=p2->pc.v[0]-p1->pc.v[0];
138 dy=p2->pc.v[1]-p1->pc.v[1];
139 dz=p2->pc.v[2]-p1->pc.v[2];
140 dw=p2->pc.v[3]-p1->pc.v[3];
148 if (ClipLine1(dx+dw,-x1-w1,&tmin,&tmax) &&
149 ClipLine1(-dx+dw,x1-w1,&tmin,&tmax) &&
150 ClipLine1(dy+dw,-y1-w1,&tmin,&tmax) &&
151 ClipLine1(-dy+dw,y1-w1,&tmin,&tmax) &&
152 ClipLine1(dz+dw,-z1-w1,&tmin,&tmax) &&
153 ClipLine1(-dz+dw,z1-w1,&tmin,&tmax)) {
155 interpolate(&q1,p1,p2,tmin);
156 interpolate(&q2,p1,p2,tmax);
157 gl_transform_to_viewport(c,&q1);
158 gl_transform_to_viewport(c,&q2);
161 ZB_line_z(c->zb,&q1.zp,&q2.zp);
163 ZB_line(c->zb,&q1.zp,&q2.zp);
180 #define clip_func(name, sign, dir, dir1, dir2) \
181 static PN_stdfloat name(V4 *c, V4 *a, V4 *b) \
185 d[0] = (b->v[0] - a->v[0]);\
186 d[1] = (b->v[1] - a->v[1]);\
187 d[2] = (b->v[2] - a->v[2]);\
188 d[3] = (b->v[3] - a->v[3]);\
189 den = -(sign d[dir]) + d[3];\
191 else t = ( sign a->v[dir] - a->v[3]) / den;\
192 c->v[dir1] = a->v[dir1] + t * d[dir1];\
193 c->v[dir2] = a->v[dir2] + t * d[dir2];\
194 c->v[3] = a->v[3] + t * d[3];\
195 c->v[dir] = sign c->v[3];\
200 clip_func(clip_xmin, -, 0, 1, 2)
202 clip_func(clip_xmax, +, 0, 1, 2)
204 clip_func(clip_ymin, -, 1, 0, 2)
206 clip_func(clip_ymax, +, 1, 0, 2)
208 clip_func(clip_zmin, -, 2, 0, 1)
210 clip_func(clip_zmax, +, 2, 0, 1)
213 PN_stdfloat (*clip_proc[6])(
V4 *,V4 *,V4 *)= {
219 static inline void updateTmp(
GLContext *c,
222 if (c->smooth_shade_model) {
223 q->color.v[0]=p0->color.v[0] + (p1->color.v[0]-p0->color.v[0])*t;
224 q->color.v[1]=p0->color.v[1] + (p1->color.v[1]-p0->color.v[1])*t;
225 q->color.v[2]=p0->color.v[2] + (p1->color.v[2]-p0->color.v[2])*t;
226 q->color.v[3]=p0->color.v[3] + (p1->color.v[3]-p0->color.v[3])*t;
228 q->color.v[0]=p0->color.v[0];
229 q->color.v[1]=p0->color.v[1];
230 q->color.v[2]=p0->color.v[2];
231 q->color.v[3]=p0->color.v[3];
234 for (
int si = 0; si < c->num_textures_enabled; ++si) {
235 q->tex_coord[si].v[0]=p0->tex_coord[si].v[0] + (p1->tex_coord[si].v[0]-p0->tex_coord[si].v[0])*t;
236 q->tex_coord[si].v[1]=p0->tex_coord[si].v[1] + (p1->tex_coord[si].v[1]-p0->tex_coord[si].v[1])*t;
239 q->clip_code=gl_clipcode(q->pc.v[0],q->pc.v[1],q->pc.v[2],q->pc.v[3]);
240 if (q->clip_code==0) {
241 gl_transform_to_viewport(c,q);
245 static void gl_draw_triangle_clip(
GLContext *c,
251 int co,c_and,cc[3],front;
258 co=cc[0] | cc[1] | cc[2];
263 norm=(PN_stdfloat)(p1->zp.x-p0->zp.x)*(PN_stdfloat)(p2->zp.y-p0->zp.y)-
264 (PN_stdfloat)(p2->zp.x-p0->zp.x)*(PN_stdfloat)(p1->zp.y-p0->zp.y);
266 if (norm == 0)
return;
271 if (c->cull_face_enabled) {
273 if (c->cull_clockwise) {
274 if (front == 0)
return;
275 c->draw_triangle_front(c,p0,p1,p2);
277 if (front != 0)
return;
278 c->draw_triangle_back(c,p0,p1,p2);
283 c->draw_triangle_front(c,p0,p1,p2);
285 c->draw_triangle_back(c,p0,p1,p2);
289 c_and=cc[0] & cc[1] & cc[2];
291 gl_draw_triangle_clip(c,p0,p1,p2,0);
296 static void gl_draw_triangle_clip(
GLContext *c,
299 int co,c_and,co1,cc[3],edge_flag_tmp,clip_mask;
307 co=cc[0] | cc[1] | cc[2];
309 gl_draw_triangle(c,p0,p1,p2);
311 c_and=cc[0] & cc[1] & cc[2];
313 if (c_and!=0)
return;
316 while (clip_bit < 6 && (co & (1 << clip_bit)) == 0) {
324 printf(
"%f %f %f %f\n",p0->pc.v[0],p0->pc.v[1],p0->pc.v[2],p0->pc.v[3]);
325 printf(
"%f %f %f %f\n",p1->pc.v[0],p1->pc.v[1],p1->pc.v[2],p1->pc.v[3]);
326 printf(
"%f %f %f %f\n",p2->pc.v[0],p2->pc.v[1],p2->pc.v[2],p2->pc.v[3]);
331 clip_mask = 1 << clip_bit;
332 co1=(cc[0] ^ cc[1] ^ cc[2]) & clip_mask;
337 if (cc[0] & clip_mask) { q[0]=p0; q[1]=p1; q[2]=p2; }
338 else if (cc[1] & clip_mask) { q[0]=p1; q[1]=p2; q[2]=p0; }
339 else { q[0]=p2; q[1]=p0; q[2]=p1; }
341 tt=clip_proc[clip_bit](&tmp1.pc,&q[0]->pc,&q[1]->pc);
342 updateTmp(c,&tmp1,q[0],q[1],tt);
344 tt=clip_proc[clip_bit](&tmp2.pc,&q[0]->pc,&q[2]->pc);
345 updateTmp(c,&tmp2,q[0],q[2],tt);
347 tmp1.edge_flag=q[0]->edge_flag;
348 edge_flag_tmp=q[2]->edge_flag;
350 gl_draw_triangle_clip(c,&tmp1,q[1],q[2],clip_bit+1);
354 q[2]->edge_flag=edge_flag_tmp;
355 gl_draw_triangle_clip(c,&tmp2,&tmp1,q[2],clip_bit+1);
359 if ((cc[0] & clip_mask)==0) { q[0]=p0; q[1]=p1; q[2]=p2; }
360 else if ((cc[1] & clip_mask)==0) { q[0]=p1; q[1]=p2; q[2]=p0; }
361 else { q[0]=p2; q[1]=p0; q[2]=p1; }
363 tt=clip_proc[clip_bit](&tmp1.pc,&q[0]->pc,&q[1]->pc);
364 updateTmp(c,&tmp1,q[0],q[1],tt);
366 tt=clip_proc[clip_bit](&tmp2.pc,&q[0]->pc,&q[2]->pc);
367 updateTmp(c,&tmp2,q[0],q[2],tt);
370 tmp2.edge_flag=q[2]->edge_flag;
371 gl_draw_triangle_clip(c,q[0],&tmp1,&tmp2,clip_bit+1);
378 int count_triangles,count_triangles_textured,count_pixels;
387 assert(p0->zp.x >= 0 && p0->zp.x < c->zb->xsize);
388 assert(p0->zp.y >= 0 && p0->zp.y < c->zb->ysize);
389 assert(p1->zp.x >= 0 && p1->zp.x < c->zb->xsize);
390 assert(p1->zp.y >= 0 && p1->zp.y < c->zb->ysize);
391 assert(p2->zp.x >= 0 && p2->zp.x < c->zb->xsize);
392 assert(p2->zp.y >= 0 && p2->zp.y < c->zb->ysize);
394 norm=(p1->zp.x-p0->zp.x)*(p2->zp.y-p0->zp.y)-
395 (p2->zp.x-p0->zp.x)*(p1->zp.y-p0->zp.y);
396 count_pixels+=abs(norm)/2;
402 if (c->num_textures_enabled != 0) {
403 count_triangles_textured++;
407 (*c->zb_fill_tri)(c->zb,&p0->zp,&p1->zp,&p2->zp);
416 if (p0->edge_flag) ZB_line_z(c->zb,&p0->zp,&p1->zp);
417 if (p1->edge_flag) ZB_line_z(c->zb,&p1->zp,&p2->zp);
418 if (p2->edge_flag) ZB_line_z(c->zb,&p2->zp,&p0->zp);
420 if (p0->edge_flag) ZB_line(c->zb,&p0->zp,&p1->zp);
421 if (p1->edge_flag) ZB_line(c->zb,&p1->zp,&p2->zp);
422 if (p2->edge_flag) ZB_line(c->zb,&p2->zp,&p0->zp);
429 void gl_draw_triangle_point(
GLContext *c,
432 if (p0->edge_flag) ZB_plot(c->zb,&p0->zp);
433 if (p1->edge_flag) ZB_plot(c->zb,&p1->zp);
434 if (p2->edge_flag) ZB_plot(c->zb,&p2->zp);