s_triangle.c revision 36a0a3252e1e20df69b53f70ba93bc74c4a4bf0e
1/*
2 * Mesa 3-D graphics library
3 * Version:  5.1
4 *
5 * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26/*
27 * When the device driver doesn't implement triangle rasterization it
28 * can hook in _swrast_Triangle, which eventually calls one of these
29 * functions to draw triangles.
30 */
31
32#include "glheader.h"
33#include "context.h"
34#include "colormac.h"
35#include "imports.h"
36#include "macros.h"
37#include "texformat.h"
38#include "teximage.h"
39#include "texstate.h"
40
41#include "s_aatriangle.h"
42#include "s_context.h"
43#include "s_depth.h"
44#include "s_feedback.h"
45#include "s_span.h"
46#include "s_triangle.h"
47
48
49/*
50 * Just used for feedback mode.
51 */
52GLboolean _swrast_culltriangle( GLcontext *ctx,
53			    const SWvertex *v0,
54			    const SWvertex *v1,
55			    const SWvertex *v2 )
56{
57   GLfloat ex = v1->win[0] - v0->win[0];
58   GLfloat ey = v1->win[1] - v0->win[1];
59   GLfloat fx = v2->win[0] - v0->win[0];
60   GLfloat fy = v2->win[1] - v0->win[1];
61   GLfloat c = ex*fy-ey*fx;
62
63   if (c * SWRAST_CONTEXT(ctx)->_backface_sign > 0)
64      return 0;
65
66   return 1;
67}
68
69
70
71/*
72 * Render a flat-shaded color index triangle.
73 */
74#define NAME flat_ci_triangle
75#define INTERP_Z 1
76#define INTERP_FOG 1
77#define SETUP_CODE			\
78   span.interpMask |= SPAN_INDEX;	\
79   span.index = IntToFixed(v2->index);	\
80   span.indexStep = 0;
81#define RENDER_SPAN( span )  _swrast_write_index_span(ctx, &span);
82#include "s_tritemp.h"
83
84
85
86/*
87 * Render a smooth-shaded color index triangle.
88 */
89#define NAME smooth_ci_triangle
90#define INTERP_Z 1
91#define INTERP_FOG 1
92#define INTERP_INDEX 1
93#define RENDER_SPAN( span )  _swrast_write_index_span(ctx, &span);
94#include "s_tritemp.h"
95
96
97
98/*
99 * Render a flat-shaded RGBA triangle.
100 */
101#define NAME flat_rgba_triangle
102#define INTERP_Z 1
103#define INTERP_FOG 1
104#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
105#define SETUP_CODE				\
106   ASSERT(ctx->Texture._EnabledCoordUnits == 0);\
107   ASSERT(ctx->Light.ShadeModel==GL_FLAT);	\
108   span.interpMask |= SPAN_RGBA;		\
109   span.red = ChanToFixed(v2->color[0]);	\
110   span.green = ChanToFixed(v2->color[1]);	\
111   span.blue = ChanToFixed(v2->color[2]);	\
112   span.alpha = ChanToFixed(v2->color[3]);	\
113   span.redStep = 0;				\
114   span.greenStep = 0;				\
115   span.blueStep = 0;				\
116   span.alphaStep = 0;
117#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
118#include "s_tritemp.h"
119
120
121
122/*
123 * Render a smooth-shaded RGBA triangle.
124 */
125#define NAME smooth_rgba_triangle
126#define INTERP_Z 1
127#define INTERP_FOG 1
128#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
129#define INTERP_RGB 1
130#define INTERP_ALPHA 1
131#define SETUP_CODE				\
132   {						\
133      /* texturing must be off */		\
134      ASSERT(ctx->Texture._EnabledCoordUnits == 0);	\
135      ASSERT(ctx->Light.ShadeModel==GL_SMOOTH);	\
136   }
137#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
138#include "s_tritemp.h"
139
140
141
142/*
143 * Render an RGB, GL_DECAL, textured triangle.
144 * Interpolate S,T only w/out mipmapping or perspective correction.
145 *
146 * No fog.
147 */
148#define NAME simple_textured_triangle
149#define INTERP_INT_TEX 1
150#define S_SCALE twidth
151#define T_SCALE theight
152
153#define SETUP_CODE							\
154   SWcontext *swrast = SWRAST_CONTEXT(ctx);                             \
155   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
156   const GLint b = obj->BaseLevel;					\
157   const GLfloat twidth = (GLfloat) obj->Image[b]->Width;		\
158   const GLfloat theight = (GLfloat) obj->Image[b]->Height;		\
159   const GLint twidth_log2 = obj->Image[b]->WidthLog2;			\
160   const GLchan *texture = (const GLchan *) obj->Image[b]->Data;	\
161   const GLint smask = obj->Image[b]->Width - 1;			\
162   const GLint tmask = obj->Image[b]->Height - 1;			\
163   if (!texture) {							\
164      /* this shouldn't happen */					\
165      return;								\
166   }
167
168#define RENDER_SPAN( span  )						\
169   GLuint i;								\
170   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
171   span.intTex[1] -= FIXED_HALF;					\
172   for (i = 0; i < span.end; i++) {					\
173      GLint s = FixedToInt(span.intTex[0]) & smask;			\
174      GLint t = FixedToInt(span.intTex[1]) & tmask;			\
175      GLint pos = (t << twidth_log2) + s;				\
176      pos = pos + pos + pos;  /* multiply by 3 */			\
177      span.array->rgb[i][RCOMP] = texture[pos];				\
178      span.array->rgb[i][GCOMP] = texture[pos+1];			\
179      span.array->rgb[i][BCOMP] = texture[pos+2];			\
180      span.intTex[0] += span.intTexStep[0];				\
181      span.intTex[1] += span.intTexStep[1];				\
182   }									\
183   (*swrast->Driver.WriteRGBSpan)(ctx, span.end, span.x, span.y,	\
184                                  (CONST GLchan (*)[3]) span.array->rgb,\
185                                  NULL );
186#include "s_tritemp.h"
187
188
189
190/*
191 * Render an RGB, GL_DECAL, textured triangle.
192 * Interpolate S,T, GL_LESS depth test, w/out mipmapping or
193 * perspective correction.
194 *
195 * No fog.
196 */
197#define NAME simple_z_textured_triangle
198#define INTERP_Z 1
199#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
200#define INTERP_INT_TEX 1
201#define S_SCALE twidth
202#define T_SCALE theight
203
204#define SETUP_CODE							\
205   SWcontext *swrast = SWRAST_CONTEXT(ctx);                             \
206   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
207   const GLint b = obj->BaseLevel;					\
208   const GLfloat twidth = (GLfloat) obj->Image[b]->Width;		\
209   const GLfloat theight = (GLfloat) obj->Image[b]->Height;		\
210   const GLint twidth_log2 = obj->Image[b]->WidthLog2;			\
211   const GLchan *texture = (const GLchan *) obj->Image[b]->Data;	\
212   const GLint smask = obj->Image[b]->Width - 1;			\
213   const GLint tmask = obj->Image[b]->Height - 1;			\
214   if (!texture) {							\
215      /* this shouldn't happen */					\
216      return;								\
217   }
218
219#define RENDER_SPAN( span )						\
220   GLuint i;				    				\
221   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
222   span.intTex[1] -= FIXED_HALF;					\
223   for (i = 0; i < span.end; i++) {					\
224      const GLdepth z = FixedToDepth(span.z);				\
225      if (z < zRow[i]) {						\
226         GLint s = FixedToInt(span.intTex[0]) & smask;			\
227         GLint t = FixedToInt(span.intTex[1]) & tmask;			\
228         GLint pos = (t << twidth_log2) + s;				\
229         pos = pos + pos + pos;  /* multiply by 3 */			\
230         span.array->rgb[i][RCOMP] = texture[pos];			\
231         span.array->rgb[i][GCOMP] = texture[pos+1];			\
232         span.array->rgb[i][BCOMP] = texture[pos+2];			\
233         zRow[i] = z;							\
234         span.array->mask[i] = 1;					\
235      }									\
236      else {								\
237         span.array->mask[i] = 0;					\
238      }									\
239      span.intTex[0] += span.intTexStep[0];				\
240      span.intTex[1] += span.intTexStep[1];				\
241      span.z += span.zStep;						\
242   }									\
243   (*swrast->Driver.WriteRGBSpan)(ctx, span.end, span.x, span.y,	\
244                                  (CONST GLchan (*)[3]) span.array->rgb,\
245                                  span.array->mask );
246#include "s_tritemp.h"
247
248
249
250#if CHAN_TYPE != GL_FLOAT
251
252struct affine_info
253{
254   GLenum filter;
255   GLenum format;
256   GLenum envmode;
257   GLint smask, tmask;
258   GLint twidth_log2;
259   const GLchan *texture;
260   GLfixed er, eg, eb, ea;
261   GLint tbytesline, tsize;
262};
263
264
265/* This function can handle GL_NEAREST or GL_LINEAR sampling of 2D RGB or RGBA
266 * textures with GL_REPLACE, GL_MODULATE, GL_BLEND, GL_DECAL or GL_ADD
267 * texture env modes.
268 */
269static INLINE void
270affine_span(GLcontext *ctx, struct sw_span *span,
271            struct affine_info *info)
272{
273   GLchan sample[4];  /* the filtered texture sample */
274
275   /* Instead of defining a function for each mode, a test is done
276    * between the outer and inner loops. This is to reduce code size
277    * and complexity. Observe that an optimizing compiler kills
278    * unused variables (for instance tf,sf,ti,si in case of GL_NEAREST).
279    */
280
281#define NEAREST_RGB			\
282   sample[RCOMP] = tex00[RCOMP];	\
283   sample[GCOMP] = tex00[GCOMP];	\
284   sample[BCOMP] = tex00[BCOMP];	\
285   sample[ACOMP] = CHAN_MAX
286
287#define LINEAR_RGB							\
288   sample[RCOMP] = (ti * (si * tex00[0] + sf * tex01[0]) +		\
289             tf * (si * tex10[0] + sf * tex11[0])) >> 2 * FIXED_SHIFT;	\
290   sample[GCOMP] = (ti * (si * tex00[1] + sf * tex01[1]) +		\
291             tf * (si * tex10[1] + sf * tex11[1])) >> 2 * FIXED_SHIFT;	\
292   sample[BCOMP] = (ti * (si * tex00[2] + sf * tex01[2]) +		\
293             tf * (si * tex10[2] + sf * tex11[2])) >> 2 * FIXED_SHIFT;	\
294   sample[ACOMP] = CHAN_MAX
295
296#define NEAREST_RGBA  COPY_CHAN4(sample, tex00)
297
298#define LINEAR_RGBA							\
299   sample[RCOMP] = (ti * (si * tex00[0] + sf * tex01[0]) +		\
300               tf * (si * tex10[0] + sf * tex11[0])) >> 2 * FIXED_SHIFT;\
301   sample[GCOMP] = (ti * (si * tex00[1] + sf * tex01[1]) +		\
302               tf * (si * tex10[1] + sf * tex11[1])) >> 2 * FIXED_SHIFT;\
303   sample[BCOMP] = (ti * (si * tex00[2] + sf * tex01[2]) +		\
304               tf * (si * tex10[2] + sf * tex11[2])) >> 2 * FIXED_SHIFT;\
305   sample[ACOMP] = (ti * (si * tex00[3] + sf * tex01[3]) +		\
306               tf * (si * tex10[3] + sf * tex11[3])) >> 2 * FIXED_SHIFT
307
308#define MODULATE							  \
309   dest[RCOMP] = span->red   * (sample[RCOMP] + 1u) >> (FIXED_SHIFT + 8); \
310   dest[GCOMP] = span->green * (sample[GCOMP] + 1u) >> (FIXED_SHIFT + 8); \
311   dest[BCOMP] = span->blue  * (sample[BCOMP] + 1u) >> (FIXED_SHIFT + 8); \
312   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1u) >> (FIXED_SHIFT + 8)
313
314#define DECAL								\
315   dest[RCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->red +		\
316               ((sample[ACOMP] + 1) * sample[RCOMP] << FIXED_SHIFT))	\
317               >> (FIXED_SHIFT + 8);					\
318   dest[GCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->green +		\
319               ((sample[ACOMP] + 1) * sample[GCOMP] << FIXED_SHIFT))	\
320               >> (FIXED_SHIFT + 8);					\
321   dest[BCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->blue +		\
322               ((sample[ACOMP] + 1) * sample[BCOMP] << FIXED_SHIFT))	\
323               >> (FIXED_SHIFT + 8);					\
324   dest[ACOMP] = FixedToInt(span->alpha)
325
326#define BLEND								\
327   dest[RCOMP] = ((CHAN_MAX - sample[RCOMP]) * span->red		\
328               + (sample[RCOMP] + 1) * info->er) >> (FIXED_SHIFT + 8);	\
329   dest[GCOMP] = ((CHAN_MAX - sample[GCOMP]) * span->green		\
330               + (sample[GCOMP] + 1) * info->eg) >> (FIXED_SHIFT + 8);	\
331   dest[BCOMP] = ((CHAN_MAX - sample[BCOMP]) * span->blue		\
332               + (sample[BCOMP] + 1) * info->eb) >> (FIXED_SHIFT + 8);	\
333   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8)
334
335#define REPLACE  COPY_CHAN4(dest, sample)
336
337#define ADD								\
338   {									\
339      GLint rSum = FixedToInt(span->red)   + (GLint) sample[RCOMP];	\
340      GLint gSum = FixedToInt(span->green) + (GLint) sample[GCOMP];	\
341      GLint bSum = FixedToInt(span->blue)  + (GLint) sample[BCOMP];	\
342      dest[RCOMP] = MIN2(rSum, CHAN_MAX);				\
343      dest[GCOMP] = MIN2(gSum, CHAN_MAX);				\
344      dest[BCOMP] = MIN2(bSum, CHAN_MAX);				\
345      dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8); \
346  }
347
348/* shortcuts */
349
350#define NEAREST_RGB_REPLACE		\
351   NEAREST_RGB;				\
352   dest[0] = sample[0];			\
353   dest[1] = sample[1];			\
354   dest[2] = sample[2];			\
355   dest[3] = FixedToInt(span->alpha);
356
357#define NEAREST_RGBA_REPLACE  COPY_CHAN4(dest, tex00)
358
359#define SPAN_NEAREST(DO_TEX,COMP)					\
360	for (i = 0; i < span->end; i++) {				\
361           /* Isn't it necessary to use FixedFloor below?? */		\
362           GLint s = FixedToInt(span->intTex[0]) & info->smask;		\
363           GLint t = FixedToInt(span->intTex[1]) & info->tmask;		\
364           GLint pos = (t << info->twidth_log2) + s;			\
365           const GLchan *tex00 = info->texture + COMP * pos;		\
366           DO_TEX;							\
367           span->red += span->redStep;					\
368	   span->green += span->greenStep;				\
369           span->blue += span->blueStep;				\
370	   span->alpha += span->alphaStep;				\
371	   span->intTex[0] += span->intTexStep[0];			\
372	   span->intTex[1] += span->intTexStep[1];			\
373           dest += 4;							\
374	}
375
376#define SPAN_LINEAR(DO_TEX,COMP)					\
377	for (i = 0; i < span->end; i++) {				\
378           /* Isn't it necessary to use FixedFloor below?? */		\
379           GLint s = FixedToInt(span->intTex[0]) & info->smask;		\
380           GLint t = FixedToInt(span->intTex[1]) & info->tmask;		\
381           GLfixed sf = span->intTex[0] & FIXED_FRAC_MASK;		\
382           GLfixed tf = span->intTex[1] & FIXED_FRAC_MASK;		\
383           GLfixed si = FIXED_FRAC_MASK - sf;				\
384           GLfixed ti = FIXED_FRAC_MASK - tf;				\
385           GLint pos = (t << info->twidth_log2) + s;			\
386           const GLchan *tex00 = info->texture + COMP * pos;		\
387           const GLchan *tex10 = tex00 + info->tbytesline;		\
388           const GLchan *tex01 = tex00 + COMP;				\
389           const GLchan *tex11 = tex10 + COMP;				\
390           (void) ti;							\
391           (void) si;							\
392           if (t == info->tmask) {					\
393              tex10 -= info->tsize;					\
394              tex11 -= info->tsize;					\
395           }								\
396           if (s == info->smask) {					\
397              tex01 -= info->tbytesline;				\
398              tex11 -= info->tbytesline;				\
399           }								\
400           DO_TEX;							\
401           span->red += span->redStep;					\
402	   span->green += span->greenStep;				\
403           span->blue += span->blueStep;				\
404	   span->alpha += span->alphaStep;				\
405	   span->intTex[0] += span->intTexStep[0];			\
406	   span->intTex[1] += span->intTexStep[1];			\
407           dest += 4;							\
408	}
409
410
411   GLuint i;
412   GLchan *dest = span->array->rgba[0];
413
414   span->intTex[0] -= FIXED_HALF;
415   span->intTex[1] -= FIXED_HALF;
416   switch (info->filter) {
417   case GL_NEAREST:
418      switch (info->format) {
419      case GL_RGB:
420         switch (info->envmode) {
421         case GL_MODULATE:
422            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
423            break;
424         case GL_DECAL:
425         case GL_REPLACE:
426            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
427            break;
428         case GL_BLEND:
429            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
430            break;
431         case GL_ADD:
432            SPAN_NEAREST(NEAREST_RGB;ADD,3);
433            break;
434         default:
435            _mesa_problem(ctx, "bad tex env mode in SPAN_LINEAR");
436            return;
437         }
438         break;
439      case GL_RGBA:
440         switch(info->envmode) {
441         case GL_MODULATE:
442            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
443            break;
444         case GL_DECAL:
445            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
446            break;
447         case GL_BLEND:
448            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
449            break;
450         case GL_ADD:
451            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
452            break;
453         case GL_REPLACE:
454            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
455            break;
456         default:
457            _mesa_problem(ctx, "bad tex env mode (2) in SPAN_LINEAR");
458            return;
459         }
460         break;
461      }
462      break;
463
464   case GL_LINEAR:
465      span->intTex[0] -= FIXED_HALF;
466      span->intTex[1] -= FIXED_HALF;
467      switch (info->format) {
468      case GL_RGB:
469         switch (info->envmode) {
470         case GL_MODULATE:
471            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
472            break;
473         case GL_DECAL:
474         case GL_REPLACE:
475            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
476            break;
477         case GL_BLEND:
478            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
479            break;
480         case GL_ADD:
481            SPAN_LINEAR(LINEAR_RGB;ADD,3);
482            break;
483         default:
484            _mesa_problem(ctx, "bad tex env mode (3) in SPAN_LINEAR");
485            return;
486         }
487         break;
488      case GL_RGBA:
489         switch (info->envmode) {
490         case GL_MODULATE:
491            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
492            break;
493         case GL_DECAL:
494            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
495            break;
496         case GL_BLEND:
497            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
498            break;
499         case GL_ADD:
500            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
501            break;
502         case GL_REPLACE:
503            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
504            break;
505         default:
506            _mesa_problem(ctx, "bad tex env mode (4) in SPAN_LINEAR");
507            return;
508         }
509         break;
510      }
511      break;
512   }
513   span->interpMask &= ~SPAN_RGBA;
514   ASSERT(span->arrayMask & SPAN_RGBA);
515   _swrast_write_rgba_span(ctx, span);
516
517#undef SPAN_NEAREST
518#undef SPAN_LINEAR
519}
520
521
522
523/*
524 * Render an RGB/RGBA textured triangle without perspective correction.
525 */
526#define NAME affine_textured_triangle
527#define INTERP_Z 1
528#define INTERP_FOG 1
529#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
530#define INTERP_RGB 1
531#define INTERP_ALPHA 1
532#define INTERP_INT_TEX 1
533#define S_SCALE twidth
534#define T_SCALE theight
535
536#define SETUP_CODE							\
537   struct affine_info info;						\
538   struct gl_texture_unit *unit = ctx->Texture.Unit+0;			\
539   struct gl_texture_object *obj = unit->Current2D;			\
540   const GLint b = obj->BaseLevel;					\
541   const GLfloat twidth = (GLfloat) obj->Image[b]->Width;		\
542   const GLfloat theight = (GLfloat) obj->Image[b]->Height;		\
543   info.texture = (const GLchan *) obj->Image[b]->Data;			\
544   info.twidth_log2 = obj->Image[b]->WidthLog2;				\
545   info.smask = obj->Image[b]->Width - 1;				\
546   info.tmask = obj->Image[b]->Height - 1;				\
547   info.format = obj->Image[b]->Format;					\
548   info.filter = obj->MinFilter;					\
549   info.envmode = unit->EnvMode;					\
550   span.arrayMask |= SPAN_RGBA;						\
551									\
552   if (info.envmode == GL_BLEND) {					\
553      /* potential off-by-one error here? (1.0f -> 2048 -> 0) */	\
554      info.er = FloatToFixed(unit->EnvColor[RCOMP] * CHAN_MAXF);	\
555      info.eg = FloatToFixed(unit->EnvColor[GCOMP] * CHAN_MAXF);	\
556      info.eb = FloatToFixed(unit->EnvColor[BCOMP] * CHAN_MAXF);	\
557      info.ea = FloatToFixed(unit->EnvColor[ACOMP] * CHAN_MAXF);	\
558   }									\
559   if (!info.texture) {							\
560      /* this shouldn't happen */					\
561      return;								\
562   }									\
563									\
564   switch (info.format) {						\
565   case GL_ALPHA:							\
566   case GL_LUMINANCE:							\
567   case GL_INTENSITY:							\
568      info.tbytesline = obj->Image[b]->Width;				\
569      break;								\
570   case GL_LUMINANCE_ALPHA:						\
571      info.tbytesline = obj->Image[b]->Width * 2;			\
572      break;								\
573   case GL_RGB:								\
574      info.tbytesline = obj->Image[b]->Width * 3;			\
575      break;								\
576   case GL_RGBA:							\
577      info.tbytesline = obj->Image[b]->Width * 4;			\
578      break;								\
579   default:								\
580      _mesa_problem(NULL, "Bad texture format in affine_texture_triangle");\
581      return;								\
582   }									\
583   info.tsize = obj->Image[b]->Height * info.tbytesline;
584
585#define RENDER_SPAN( span )   affine_span(ctx, &span, &info);
586
587#include "s_tritemp.h"
588
589
590
591struct persp_info
592{
593   GLenum filter;
594   GLenum format;
595   GLenum envmode;
596   GLint smask, tmask;
597   GLint twidth_log2;
598   const GLchan *texture;
599   GLfixed er, eg, eb, ea;   /* texture env color */
600   GLint tbytesline, tsize;
601};
602
603
604static INLINE void
605fast_persp_span(GLcontext *ctx, struct sw_span *span,
606		struct persp_info *info)
607{
608   GLchan sample[4];  /* the filtered texture sample */
609
610  /* Instead of defining a function for each mode, a test is done
611   * between the outer and inner loops. This is to reduce code size
612   * and complexity. Observe that an optimizing compiler kills
613   * unused variables (for instance tf,sf,ti,si in case of GL_NEAREST).
614   */
615#define SPAN_NEAREST(DO_TEX,COMP)					\
616	for (i = 0; i < span->end; i++) {				\
617           GLdouble invQ = tex_coord[2] ?				\
618                                 (1.0 / tex_coord[2]) : 1.0;            \
619           GLfloat s_tmp = (GLfloat) (tex_coord[0] * invQ);		\
620           GLfloat t_tmp = (GLfloat) (tex_coord[1] * invQ);		\
621           GLint s = IFLOOR(s_tmp) & info->smask;	        	\
622           GLint t = IFLOOR(t_tmp) & info->tmask;	        	\
623           GLint pos = (t << info->twidth_log2) + s;			\
624           const GLchan *tex00 = info->texture + COMP * pos;		\
625           DO_TEX;							\
626           span->red += span->redStep;					\
627	   span->green += span->greenStep;				\
628           span->blue += span->blueStep;				\
629	   span->alpha += span->alphaStep;				\
630	   tex_coord[0] += tex_step[0];					\
631	   tex_coord[1] += tex_step[1];					\
632	   tex_coord[2] += tex_step[2];					\
633           dest += 4;							\
634	}
635
636#define SPAN_LINEAR(DO_TEX,COMP)					\
637	for (i = 0; i < span->end; i++) {				\
638           GLdouble invQ = tex_coord[2] ?				\
639                                 (1.0 / tex_coord[2]) : 1.0;            \
640           GLfloat s_tmp = (GLfloat) (tex_coord[0] * invQ);		\
641           GLfloat t_tmp = (GLfloat) (tex_coord[1] * invQ);		\
642           GLfixed s_fix = FloatToFixed(s_tmp) - FIXED_HALF;		\
643           GLfixed t_fix = FloatToFixed(t_tmp) - FIXED_HALF;        	\
644           GLint s = FixedToInt(FixedFloor(s_fix)) & info->smask;	\
645           GLint t = FixedToInt(FixedFloor(t_fix)) & info->tmask;	\
646           GLfixed sf = s_fix & FIXED_FRAC_MASK;			\
647           GLfixed tf = t_fix & FIXED_FRAC_MASK;			\
648           GLfixed si = FIXED_FRAC_MASK - sf;				\
649           GLfixed ti = FIXED_FRAC_MASK - tf;				\
650           GLint pos = (t << info->twidth_log2) + s;			\
651           const GLchan *tex00 = info->texture + COMP * pos;		\
652           const GLchan *tex10 = tex00 + info->tbytesline;		\
653           const GLchan *tex01 = tex00 + COMP;				\
654           const GLchan *tex11 = tex10 + COMP;				\
655           (void) ti;							\
656           (void) si;							\
657           if (t == info->tmask) {					\
658              tex10 -= info->tsize;					\
659              tex11 -= info->tsize;					\
660           }								\
661           if (s == info->smask) {					\
662              tex01 -= info->tbytesline;				\
663              tex11 -= info->tbytesline;				\
664           }								\
665           DO_TEX;							\
666           span->red   += span->redStep;				\
667	   span->green += span->greenStep;				\
668           span->blue  += span->blueStep;				\
669	   span->alpha += span->alphaStep;				\
670	   tex_coord[0] += tex_step[0];					\
671	   tex_coord[1] += tex_step[1];					\
672	   tex_coord[2] += tex_step[2];					\
673           dest += 4;							\
674	}
675
676   GLuint i;
677   GLfloat tex_coord[3], tex_step[3];
678   GLchan *dest = span->array->rgba[0];
679
680   tex_coord[0] = span->tex[0][0]  * (info->smask + 1);
681   tex_step[0] = span->texStepX[0][0] * (info->smask + 1);
682   tex_coord[1] = span->tex[0][1] * (info->tmask + 1);
683   tex_step[1] = span->texStepX[0][1] * (info->tmask + 1);
684   /* span->tex[0][2] only if 3D-texturing, here only 2D */
685   tex_coord[2] = span->tex[0][3];
686   tex_step[2] = span->texStepX[0][3];
687
688   switch (info->filter) {
689   case GL_NEAREST:
690      switch (info->format) {
691      case GL_RGB:
692         switch (info->envmode) {
693         case GL_MODULATE:
694            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
695            break;
696         case GL_DECAL:
697         case GL_REPLACE:
698            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
699            break;
700         case GL_BLEND:
701            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
702            break;
703         case GL_ADD:
704            SPAN_NEAREST(NEAREST_RGB;ADD,3);
705            break;
706         default:
707            _mesa_problem(ctx, "bad tex env mode (5) in SPAN_LINEAR");
708            return;
709         }
710         break;
711      case GL_RGBA:
712         switch(info->envmode) {
713         case GL_MODULATE:
714            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
715            break;
716         case GL_DECAL:
717            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
718            break;
719         case GL_BLEND:
720            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
721            break;
722         case GL_ADD:
723            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
724            break;
725         case GL_REPLACE:
726            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
727            break;
728         default:
729            _mesa_problem(ctx, "bad tex env mode (6) in SPAN_LINEAR");
730            return;
731         }
732         break;
733      }
734      break;
735
736   case GL_LINEAR:
737      switch (info->format) {
738      case GL_RGB:
739         switch (info->envmode) {
740         case GL_MODULATE:
741            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
742            break;
743         case GL_DECAL:
744         case GL_REPLACE:
745            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
746            break;
747         case GL_BLEND:
748            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
749            break;
750         case GL_ADD:
751            SPAN_LINEAR(LINEAR_RGB;ADD,3);
752            break;
753         default:
754            _mesa_problem(ctx, "bad tex env mode (7) in SPAN_LINEAR");
755            return;
756         }
757         break;
758      case GL_RGBA:
759         switch (info->envmode) {
760         case GL_MODULATE:
761            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
762            break;
763         case GL_DECAL:
764            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
765            break;
766         case GL_BLEND:
767            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
768            break;
769         case GL_ADD:
770            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
771            break;
772         case GL_REPLACE:
773            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
774            break;
775         default:
776            _mesa_problem(ctx, "bad tex env mode (8) in SPAN_LINEAR");
777            return;
778         }
779         break;
780      }
781      break;
782   }
783
784   ASSERT(span->arrayMask & SPAN_RGBA);
785   _swrast_write_rgba_span(ctx, span);
786
787#undef SPAN_NEAREST
788#undef SPAN_LINEAR
789}
790
791
792/*
793 * Render an perspective corrected RGB/RGBA textured triangle.
794 * The Q (aka V in Mesa) coordinate must be zero such that the divide
795 * by interpolated Q/W comes out right.
796 *
797 */
798#define NAME persp_textured_triangle
799#define INTERP_Z 1
800#define INTERP_FOG 1
801#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
802#define INTERP_RGB 1
803#define INTERP_ALPHA 1
804#define INTERP_TEX 1
805
806#define SETUP_CODE							\
807   struct persp_info info;						\
808   const struct gl_texture_unit *unit = ctx->Texture.Unit+0;		\
809   const struct gl_texture_object *obj = unit->Current2D;		\
810   const GLint b = obj->BaseLevel;					\
811   info.texture = (const GLchan *) obj->Image[b]->Data;			\
812   info.twidth_log2 = obj->Image[b]->WidthLog2;				\
813   info.smask = obj->Image[b]->Width - 1;				\
814   info.tmask = obj->Image[b]->Height - 1;				\
815   info.format = obj->Image[b]->Format;					\
816   info.filter = obj->MinFilter;					\
817   info.envmode = unit->EnvMode;					\
818									\
819   if (info.envmode == GL_BLEND) {					\
820      /* potential off-by-one error here? (1.0f -> 2048 -> 0) */	\
821      info.er = FloatToFixed(unit->EnvColor[RCOMP] * CHAN_MAXF);	\
822      info.eg = FloatToFixed(unit->EnvColor[GCOMP] * CHAN_MAXF);	\
823      info.eb = FloatToFixed(unit->EnvColor[BCOMP] * CHAN_MAXF);	\
824      info.ea = FloatToFixed(unit->EnvColor[ACOMP] * CHAN_MAXF);	\
825   }									\
826   if (!info.texture) {							\
827      /* this shouldn't happen */					\
828      return;								\
829   }									\
830									\
831   switch (info.format) {						\
832   case GL_ALPHA:							\
833   case GL_LUMINANCE:							\
834   case GL_INTENSITY:							\
835      info.tbytesline = obj->Image[b]->Width;				\
836      break;								\
837   case GL_LUMINANCE_ALPHA:						\
838      info.tbytesline = obj->Image[b]->Width * 2;			\
839      break;								\
840   case GL_RGB:								\
841      info.tbytesline = obj->Image[b]->Width * 3;			\
842      break;								\
843   case GL_RGBA:							\
844      info.tbytesline = obj->Image[b]->Width * 4;			\
845      break;								\
846   default:								\
847      _mesa_problem(NULL, "Bad texture format in persp_textured_triangle");\
848      return;								\
849   }									\
850   info.tsize = obj->Image[b]->Height * info.tbytesline;
851
852#define RENDER_SPAN( span )			\
853   span.interpMask &= ~SPAN_RGBA;		\
854   span.arrayMask |= SPAN_RGBA;			\
855   fast_persp_span(ctx, &span, &info);
856
857#include "s_tritemp.h"
858
859
860#endif /* CHAN_BITS != GL_FLOAT */
861
862
863
864
865/*
866 * Render a smooth-shaded, textured, RGBA triangle.
867 * Interpolate S,T,R with perspective correction, w/out mipmapping.
868 */
869#define NAME general_textured_triangle
870#define INTERP_Z 1
871#define INTERP_W 1
872#define INTERP_FOG 1
873#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
874#define INTERP_RGB 1
875#define INTERP_SPEC 1
876#define INTERP_ALPHA 1
877#define INTERP_TEX 1
878#define RENDER_SPAN( span )   _swrast_write_texture_span(ctx, &span);
879#include "s_tritemp.h"
880
881
882
883/*
884 * This is the big one!
885 * Interpolate Z, RGB, Alpha, specular, fog, and N sets of texture coordinates.
886 * Yup, it's slow.
887 */
888#define NAME multitextured_triangle
889#define INTERP_Z 1
890#define INTERP_W 1
891#define INTERP_FOG 1
892#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
893#define INTERP_RGB 1
894#define INTERP_ALPHA 1
895#define INTERP_SPEC 1
896#define INTERP_MULTITEX 1
897#define RENDER_SPAN( span )   _swrast_write_texture_span(ctx, &span);
898#include "s_tritemp.h"
899
900
901
902#define NAME occlusion_zless_triangle
903#define DO_OCCLUSION_TEST
904#define INTERP_Z 1
905#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
906#define SETUP_CODE			\
907   if (ctx->OcclusionResult) {		\
908      return;				\
909   }
910#define RENDER_SPAN( span )				\
911   GLuint i;						\
912   for (i = 0; i < span.end; i++) {			\
913      GLdepth z = FixedToDepth(span.z);			\
914      if (z < zRow[i]) {				\
915         ctx->OcclusionResult = GL_TRUE;		\
916         return;					\
917      }							\
918      span.z += span.zStep;				\
919   }
920#include "s_tritemp.h"
921
922
923
924static void
925nodraw_triangle( GLcontext *ctx,
926                 const SWvertex *v0,
927                 const SWvertex *v1,
928                 const SWvertex *v2 )
929{
930   (void) (ctx && v0 && v1 && v2);
931}
932
933
934/*
935 * This is used when separate specular color is enabled, but not
936 * texturing.  We add the specular color to the primary color,
937 * draw the triangle, then restore the original primary color.
938 * Inefficient, but seldom needed.
939 */
940void _swrast_add_spec_terms_triangle( GLcontext *ctx,
941				      const SWvertex *v0,
942				      const SWvertex *v1,
943				      const SWvertex *v2 )
944{
945   SWvertex *ncv0 = (SWvertex *)v0; /* drop const qualifier */
946   SWvertex *ncv1 = (SWvertex *)v1;
947   SWvertex *ncv2 = (SWvertex *)v2;
948#if CHAN_TYPE == GL_FLOAT
949   GLfloat rSum, gSum, bSum;
950#else
951   GLint rSum, gSum, bSum;
952#endif
953   GLchan c[3][4];
954   /* save original colors */
955   COPY_CHAN4( c[0], ncv0->color );
956   COPY_CHAN4( c[1], ncv1->color );
957   COPY_CHAN4( c[2], ncv2->color );
958   /* sum v0 */
959   rSum = ncv0->color[0] + ncv0->specular[0];
960   gSum = ncv0->color[1] + ncv0->specular[1];
961   bSum = ncv0->color[2] + ncv0->specular[2];
962   ncv0->color[0] = MIN2(rSum, CHAN_MAX);
963   ncv0->color[1] = MIN2(gSum, CHAN_MAX);
964   ncv0->color[2] = MIN2(bSum, CHAN_MAX);
965   /* sum v1 */
966   rSum = ncv1->color[0] + ncv1->specular[0];
967   gSum = ncv1->color[1] + ncv1->specular[1];
968   bSum = ncv1->color[2] + ncv1->specular[2];
969   ncv1->color[0] = MIN2(rSum, CHAN_MAX);
970   ncv1->color[1] = MIN2(gSum, CHAN_MAX);
971   ncv1->color[2] = MIN2(bSum, CHAN_MAX);
972   /* sum v2 */
973   rSum = ncv2->color[0] + ncv2->specular[0];
974   gSum = ncv2->color[1] + ncv2->specular[1];
975   bSum = ncv2->color[2] + ncv2->specular[2];
976   ncv2->color[0] = MIN2(rSum, CHAN_MAX);
977   ncv2->color[1] = MIN2(gSum, CHAN_MAX);
978   ncv2->color[2] = MIN2(bSum, CHAN_MAX);
979   /* draw */
980   SWRAST_CONTEXT(ctx)->SpecTriangle( ctx, ncv0, ncv1, ncv2 );
981   /* restore original colors */
982   COPY_CHAN4( ncv0->color, c[0] );
983   COPY_CHAN4( ncv1->color, c[1] );
984   COPY_CHAN4( ncv2->color, c[2] );
985}
986
987
988
989#ifdef DEBUG
990
991/* record the current triangle function name */
992const char *_mesa_triFuncName = NULL;
993
994#define USE(triFunc)				\
995do {						\
996    _mesa_triFuncName = #triFunc;		\
997    /*printf("%s\n", _mesa_triFuncName);*/	\
998    swrast->Triangle = triFunc;			\
999} while (0)
1000
1001#else
1002
1003#define USE(triFunc)  swrast->Triangle = triFunc;
1004
1005#endif
1006
1007
1008
1009
1010/*
1011 * Determine which triangle rendering function to use given the current
1012 * rendering context.
1013 *
1014 * Please update the summary flag _SWRAST_NEW_TRIANGLE if you add or
1015 * remove tests to this code.
1016 */
1017void
1018_swrast_choose_triangle( GLcontext *ctx )
1019{
1020   SWcontext *swrast = SWRAST_CONTEXT(ctx);
1021   const GLboolean rgbmode = ctx->Visual.rgbMode;
1022
1023   if (ctx->Polygon.CullFlag &&
1024       ctx->Polygon.CullFaceMode == GL_FRONT_AND_BACK) {
1025      USE(nodraw_triangle);
1026      return;
1027   }
1028
1029   if (ctx->RenderMode==GL_RENDER) {
1030
1031      if (ctx->Polygon.SmoothFlag) {
1032         _swrast_set_aa_triangle_function(ctx);
1033         ASSERT(swrast->Triangle);
1034         return;
1035      }
1036
1037      if (ctx->Depth.OcclusionTest &&
1038          ctx->Depth.Test &&
1039          ctx->Depth.Mask == GL_FALSE &&
1040          ctx->Depth.Func == GL_LESS &&
1041          !ctx->Stencil.Enabled) {
1042         if ((rgbmode &&
1043              ctx->Color.ColorMask[0] == 0 &&
1044              ctx->Color.ColorMask[1] == 0 &&
1045              ctx->Color.ColorMask[2] == 0 &&
1046              ctx->Color.ColorMask[3] == 0)
1047             ||
1048             (!rgbmode && ctx->Color.IndexMask == 0)) {
1049            USE(occlusion_zless_triangle);
1050            return;
1051         }
1052      }
1053
1054      if (ctx->Texture._EnabledCoordUnits || ctx->FragmentProgram.Enabled) {
1055         /* Ugh, we do a _lot_ of tests to pick the best textured tri func */
1056	 const struct gl_texture_object *texObj2D;
1057         const struct gl_texture_image *texImg;
1058         GLenum minFilter, magFilter, envMode;
1059         GLint format;
1060         texObj2D = ctx->Texture.Unit[0].Current2D;
1061         texImg = texObj2D ? texObj2D->Image[texObj2D->BaseLevel] : NULL;
1062         format = texImg ? texImg->TexFormat->MesaFormat : -1;
1063         minFilter = texObj2D ? texObj2D->MinFilter : (GLenum) 0;
1064         magFilter = texObj2D ? texObj2D->MagFilter : (GLenum) 0;
1065         envMode = ctx->Texture.Unit[0].EnvMode;
1066
1067         /* First see if we can use an optimized 2-D texture function */
1068         if (ctx->Texture._EnabledCoordUnits == 1
1069             && !ctx->FragmentProgram.Enabled
1070             && ctx->Texture.Unit[0]._ReallyEnabled == TEXTURE_2D_BIT
1071             && texObj2D->WrapS==GL_REPEAT
1072	     && texObj2D->WrapT==GL_REPEAT
1073             && texImg->Border==0
1074             && texImg->Width == texImg->RowStride
1075             && (format == MESA_FORMAT_RGB || format == MESA_FORMAT_RGBA)
1076	     && minFilter == magFilter
1077	     && ctx->Light.Model.ColorControl == GL_SINGLE_COLOR
1078	     && ctx->Texture.Unit[0].EnvMode != GL_COMBINE_EXT) {
1079	    if (ctx->Hint.PerspectiveCorrection==GL_FASTEST) {
1080	       if (minFilter == GL_NEAREST
1081		   && format == MESA_FORMAT_RGB
1082		   && (envMode == GL_REPLACE || envMode == GL_DECAL)
1083		   && ((swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)
1084			&& ctx->Depth.Func == GL_LESS
1085			&& ctx->Depth.Mask == GL_TRUE)
1086		       || swrast->_RasterMask == TEXTURE_BIT)
1087		   && ctx->Polygon.StippleFlag == GL_FALSE) {
1088		  if (swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)) {
1089		     USE(simple_z_textured_triangle);
1090		  }
1091		  else {
1092		     USE(simple_textured_triangle);
1093		  }
1094	       }
1095	       else {
1096#if (CHAN_BITS == 16 || CHAN_BITS == 32)
1097                  USE(general_textured_triangle);
1098#else
1099                  USE(affine_textured_triangle);
1100#endif
1101	       }
1102	    }
1103	    else {
1104#if (CHAN_BITS == 16 || CHAN_BITS == 32)
1105               USE(general_textured_triangle);
1106#else
1107               USE(persp_textured_triangle);
1108#endif
1109	    }
1110	 }
1111         else {
1112            /* general case textured triangles */
1113            if (ctx->Texture._EnabledCoordUnits > 1) {
1114               USE(multitextured_triangle);
1115            }
1116            else {
1117               USE(general_textured_triangle);
1118            }
1119         }
1120      }
1121      else {
1122         ASSERT(!ctx->Texture._EnabledCoordUnits);
1123	 if (ctx->Light.ShadeModel==GL_SMOOTH) {
1124	    /* smooth shaded, no texturing, stippled or some raster ops */
1125            if (rgbmode) {
1126	       USE(smooth_rgba_triangle);
1127            }
1128            else {
1129               USE(smooth_ci_triangle);
1130            }
1131	 }
1132	 else {
1133	    /* flat shaded, no texturing, stippled or some raster ops */
1134            if (rgbmode) {
1135	       USE(flat_rgba_triangle);
1136            }
1137            else {
1138               USE(flat_ci_triangle);
1139            }
1140	 }
1141      }
1142   }
1143   else if (ctx->RenderMode==GL_FEEDBACK) {
1144      USE(_swrast_feedback_triangle);
1145   }
1146   else {
1147      /* GL_SELECT mode */
1148      USE(_swrast_select_triangle);
1149   }
1150}
1151