s_triangle.c revision ff73c783cc47361ff0dd819c82d067b4b85870dd
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.5.3
4 *
5 * Copyright (C) 1999-2007  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
39#include "s_aatriangle.h"
40#include "s_context.h"
41#include "s_feedback.h"
42#include "s_span.h"
43#include "s_triangle.h"
44
45
46/*
47 * Just used for feedback mode.
48 */
49GLboolean
50_swrast_culltriangle( GLcontext *ctx,
51                      const SWvertex *v0,
52                      const SWvertex *v1,
53                      const SWvertex *v2 )
54{
55   GLfloat ex = v1->attrib[FRAG_ATTRIB_WPOS][0] - v0->attrib[FRAG_ATTRIB_WPOS][0];
56   GLfloat ey = v1->attrib[FRAG_ATTRIB_WPOS][1] - v0->attrib[FRAG_ATTRIB_WPOS][1];
57   GLfloat fx = v2->attrib[FRAG_ATTRIB_WPOS][0] - v0->attrib[FRAG_ATTRIB_WPOS][0];
58   GLfloat fy = v2->attrib[FRAG_ATTRIB_WPOS][1] - v0->attrib[FRAG_ATTRIB_WPOS][1];
59   GLfloat c = ex*fy-ey*fx;
60
61   if (c * SWRAST_CONTEXT(ctx)->_BackfaceCullSign > 0)
62      return 0;
63
64   return 1;
65}
66
67
68
69/*
70 * Render a smooth or flat-shaded color index triangle.
71 */
72#define NAME ci_triangle
73#define INTERP_Z 1
74#define INTERP_ATTRIBS 1  /* just for fog */
75#define INTERP_INDEX 1
76#define RENDER_SPAN( span )  _swrast_write_index_span(ctx, &span);
77#include "s_tritemp.h"
78
79
80
81/*
82 * Render a flat-shaded RGBA triangle.
83 */
84#define NAME flat_rgba_triangle
85#define INTERP_Z 1
86#define SETUP_CODE				\
87   ASSERT(ctx->Texture._EnabledCoordUnits == 0);\
88   ASSERT(ctx->Light.ShadeModel==GL_FLAT);	\
89   span.interpMask |= SPAN_RGBA;		\
90   span.red = ChanToFixed(v2->color[0]);	\
91   span.green = ChanToFixed(v2->color[1]);	\
92   span.blue = ChanToFixed(v2->color[2]);	\
93   span.alpha = ChanToFixed(v2->color[3]);	\
94   span.redStep = 0;				\
95   span.greenStep = 0;				\
96   span.blueStep = 0;				\
97   span.alphaStep = 0;
98#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
99#include "s_tritemp.h"
100
101
102
103/*
104 * Render a smooth-shaded RGBA triangle.
105 */
106#define NAME smooth_rgba_triangle
107#define INTERP_Z 1
108#define INTERP_RGB 1
109#define INTERP_ALPHA 1
110#define SETUP_CODE				\
111   {						\
112      /* texturing must be off */		\
113      ASSERT(ctx->Texture._EnabledCoordUnits == 0);	\
114      ASSERT(ctx->Light.ShadeModel==GL_SMOOTH);	\
115   }
116#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
117#include "s_tritemp.h"
118
119
120
121/*
122 * Render an RGB, GL_DECAL, textured triangle.
123 * Interpolate S,T only w/out mipmapping or perspective correction.
124 *
125 * No fog.  No depth testing.
126 */
127#define NAME simple_textured_triangle
128#define INTERP_INT_TEX 1
129#define S_SCALE twidth
130#define T_SCALE theight
131
132#define SETUP_CODE							\
133   struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0];\
134   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
135   const GLint b = obj->BaseLevel;					\
136   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
137   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
138   const GLint twidth_log2 = obj->Image[0][b]->WidthLog2;		\
139   const GLchan *texture = (const GLchan *) obj->Image[0][b]->Data;	\
140   const GLint smask = obj->Image[0][b]->Width - 1;			\
141   const GLint tmask = obj->Image[0][b]->Height - 1;			\
142   if (!texture) {							\
143      /* this shouldn't happen */					\
144      return;								\
145   }
146
147#define RENDER_SPAN( span )						\
148   GLuint i;								\
149   GLchan rgb[MAX_WIDTH][3];						\
150   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
151   span.intTex[1] -= FIXED_HALF;					\
152   for (i = 0; i < span.end; i++) {					\
153      GLint s = FixedToInt(span.intTex[0]) & smask;			\
154      GLint t = FixedToInt(span.intTex[1]) & tmask;			\
155      GLint pos = (t << twidth_log2) + s;				\
156      pos = pos + pos + pos;  /* multiply by 3 */			\
157      rgb[i][RCOMP] = texture[pos];					\
158      rgb[i][GCOMP] = texture[pos+1];					\
159      rgb[i][BCOMP] = texture[pos+2];					\
160      span.intTex[0] += span.intTexStep[0];				\
161      span.intTex[1] += span.intTexStep[1];				\
162   }									\
163   rb->PutRowRGB(ctx, rb, span.end, span.x, span.y, rgb, NULL);
164
165#include "s_tritemp.h"
166
167
168
169/*
170 * Render an RGB, GL_DECAL, textured triangle.
171 * Interpolate S,T, GL_LESS depth test, w/out mipmapping or
172 * perspective correction.
173 * Depth buffer bits must be <= sizeof(DEFAULT_SOFTWARE_DEPTH_TYPE)
174 *
175 * No fog.
176 */
177#define NAME simple_z_textured_triangle
178#define INTERP_Z 1
179#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
180#define INTERP_INT_TEX 1
181#define S_SCALE twidth
182#define T_SCALE theight
183
184#define SETUP_CODE							\
185   struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0];\
186   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
187   const GLint b = obj->BaseLevel;					\
188   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
189   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
190   const GLint twidth_log2 = obj->Image[0][b]->WidthLog2;		\
191   const GLchan *texture = (const GLchan *) obj->Image[0][b]->Data;	\
192   const GLint smask = obj->Image[0][b]->Width - 1;			\
193   const GLint tmask = obj->Image[0][b]->Height - 1;			\
194   if (!texture) {							\
195      /* this shouldn't happen */					\
196      return;								\
197   }
198
199#define RENDER_SPAN( span )						\
200   GLuint i;				    				\
201   GLchan rgb[MAX_WIDTH][3];						\
202   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
203   span.intTex[1] -= FIXED_HALF;					\
204   for (i = 0; i < span.end; i++) {					\
205      const GLuint z = FixedToDepth(span.z);				\
206      if (z < zRow[i]) {						\
207         GLint s = FixedToInt(span.intTex[0]) & smask;			\
208         GLint t = FixedToInt(span.intTex[1]) & tmask;			\
209         GLint pos = (t << twidth_log2) + s;				\
210         pos = pos + pos + pos;  /* multiply by 3 */			\
211         rgb[i][RCOMP] = texture[pos];					\
212         rgb[i][GCOMP] = texture[pos+1];				\
213         rgb[i][BCOMP] = texture[pos+2];				\
214         zRow[i] = z;							\
215         span.array->mask[i] = 1;					\
216      }									\
217      else {								\
218         span.array->mask[i] = 0;					\
219      }									\
220      span.intTex[0] += span.intTexStep[0];				\
221      span.intTex[1] += span.intTexStep[1];				\
222      span.z += span.zStep;						\
223   }									\
224   rb->PutRowRGB(ctx, rb, span.end, span.x, span.y, rgb, span.array->mask);
225
226#include "s_tritemp.h"
227
228
229#if CHAN_TYPE != GL_FLOAT
230
231struct affine_info
232{
233   GLenum filter;
234   GLenum format;
235   GLenum envmode;
236   GLint smask, tmask;
237   GLint twidth_log2;
238   const GLchan *texture;
239   GLfixed er, eg, eb, ea;
240   GLint tbytesline, tsize;
241};
242
243
244static INLINE GLint
245ilerp(GLint t, GLint a, GLint b)
246{
247   return a + ((t * (b - a)) >> FIXED_SHIFT);
248}
249
250static INLINE GLint
251ilerp_2d(GLint ia, GLint ib, GLint v00, GLint v10, GLint v01, GLint v11)
252{
253   const GLint temp0 = ilerp(ia, v00, v10);
254   const GLint temp1 = ilerp(ia, v01, v11);
255   return ilerp(ib, temp0, temp1);
256}
257
258
259/* This function can handle GL_NEAREST or GL_LINEAR sampling of 2D RGB or RGBA
260 * textures with GL_REPLACE, GL_MODULATE, GL_BLEND, GL_DECAL or GL_ADD
261 * texture env modes.
262 */
263static INLINE void
264affine_span(GLcontext *ctx, SWspan *span,
265            struct affine_info *info)
266{
267   GLchan sample[4];  /* the filtered texture sample */
268
269   /* Instead of defining a function for each mode, a test is done
270    * between the outer and inner loops. This is to reduce code size
271    * and complexity. Observe that an optimizing compiler kills
272    * unused variables (for instance tf,sf,ti,si in case of GL_NEAREST).
273    */
274
275#define NEAREST_RGB			\
276   sample[RCOMP] = tex00[RCOMP];	\
277   sample[GCOMP] = tex00[GCOMP];	\
278   sample[BCOMP] = tex00[BCOMP];	\
279   sample[ACOMP] = CHAN_MAX
280
281#define LINEAR_RGB							\
282   sample[RCOMP] = ilerp_2d(sf, tf, tex00[0], tex01[0], tex10[0], tex11[0]);\
283   sample[GCOMP] = ilerp_2d(sf, tf, tex00[1], tex01[1], tex10[1], tex11[1]);\
284   sample[BCOMP] = ilerp_2d(sf, tf, tex00[2], tex01[2], tex10[2], tex11[2]);\
285   sample[ACOMP] = CHAN_MAX;
286
287#define NEAREST_RGBA  COPY_CHAN4(sample, tex00)
288
289#define LINEAR_RGBA							\
290   sample[RCOMP] = ilerp_2d(sf, tf, tex00[0], tex01[0], tex10[0], tex11[0]);\
291   sample[GCOMP] = ilerp_2d(sf, tf, tex00[1], tex01[1], tex10[1], tex11[1]);\
292   sample[BCOMP] = ilerp_2d(sf, tf, tex00[2], tex01[2], tex10[2], tex11[2]);\
293   sample[ACOMP] = ilerp_2d(sf, tf, tex00[3], tex01[3], tex10[3], tex11[3])
294
295#define MODULATE							  \
296   dest[RCOMP] = span->red   * (sample[RCOMP] + 1u) >> (FIXED_SHIFT + 8); \
297   dest[GCOMP] = span->green * (sample[GCOMP] + 1u) >> (FIXED_SHIFT + 8); \
298   dest[BCOMP] = span->blue  * (sample[BCOMP] + 1u) >> (FIXED_SHIFT + 8); \
299   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1u) >> (FIXED_SHIFT + 8)
300
301#define DECAL								\
302   dest[RCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->red +		\
303               ((sample[ACOMP] + 1) * sample[RCOMP] << FIXED_SHIFT))	\
304               >> (FIXED_SHIFT + 8);					\
305   dest[GCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->green +		\
306               ((sample[ACOMP] + 1) * sample[GCOMP] << FIXED_SHIFT))	\
307               >> (FIXED_SHIFT + 8);					\
308   dest[BCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->blue +		\
309               ((sample[ACOMP] + 1) * sample[BCOMP] << FIXED_SHIFT))	\
310               >> (FIXED_SHIFT + 8);					\
311   dest[ACOMP] = FixedToInt(span->alpha)
312
313#define BLEND								\
314   dest[RCOMP] = ((CHAN_MAX - sample[RCOMP]) * span->red		\
315               + (sample[RCOMP] + 1) * info->er) >> (FIXED_SHIFT + 8);	\
316   dest[GCOMP] = ((CHAN_MAX - sample[GCOMP]) * span->green		\
317               + (sample[GCOMP] + 1) * info->eg) >> (FIXED_SHIFT + 8);	\
318   dest[BCOMP] = ((CHAN_MAX - sample[BCOMP]) * span->blue		\
319               + (sample[BCOMP] + 1) * info->eb) >> (FIXED_SHIFT + 8);	\
320   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8)
321
322#define REPLACE  COPY_CHAN4(dest, sample)
323
324#define ADD								\
325   {									\
326      GLint rSum = FixedToInt(span->red)   + (GLint) sample[RCOMP];	\
327      GLint gSum = FixedToInt(span->green) + (GLint) sample[GCOMP];	\
328      GLint bSum = FixedToInt(span->blue)  + (GLint) sample[BCOMP];	\
329      dest[RCOMP] = MIN2(rSum, CHAN_MAX);				\
330      dest[GCOMP] = MIN2(gSum, CHAN_MAX);				\
331      dest[BCOMP] = MIN2(bSum, CHAN_MAX);				\
332      dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8); \
333  }
334
335/* shortcuts */
336
337#define NEAREST_RGB_REPLACE		\
338   NEAREST_RGB;				\
339   dest[0] = sample[0];			\
340   dest[1] = sample[1];			\
341   dest[2] = sample[2];			\
342   dest[3] = FixedToInt(span->alpha);
343
344#define NEAREST_RGBA_REPLACE  COPY_CHAN4(dest, tex00)
345
346#define SPAN_NEAREST(DO_TEX, COMPS)					\
347	for (i = 0; i < span->end; i++) {				\
348           /* Isn't it necessary to use FixedFloor below?? */		\
349           GLint s = FixedToInt(span->intTex[0]) & info->smask;		\
350           GLint t = FixedToInt(span->intTex[1]) & info->tmask;		\
351           GLint pos = (t << info->twidth_log2) + s;			\
352           const GLchan *tex00 = info->texture + COMPS * pos;		\
353           DO_TEX;							\
354           span->red += span->redStep;					\
355	   span->green += span->greenStep;				\
356           span->blue += span->blueStep;				\
357	   span->alpha += span->alphaStep;				\
358	   span->intTex[0] += span->intTexStep[0];			\
359	   span->intTex[1] += span->intTexStep[1];			\
360           dest += 4;							\
361	}
362
363#define SPAN_LINEAR(DO_TEX, COMPS)					\
364	for (i = 0; i < span->end; i++) {				\
365           /* Isn't it necessary to use FixedFloor below?? */		\
366           const GLint s = FixedToInt(span->intTex[0]) & info->smask;	\
367           const GLint t = FixedToInt(span->intTex[1]) & info->tmask;	\
368           const GLfixed sf = span->intTex[0] & FIXED_FRAC_MASK;	\
369           const GLfixed tf = span->intTex[1] & FIXED_FRAC_MASK;	\
370           const GLint pos = (t << info->twidth_log2) + s;		\
371           const GLchan *tex00 = info->texture + COMPS * pos;		\
372           const GLchan *tex10 = tex00 + info->tbytesline;		\
373           const GLchan *tex01 = tex00 + COMPS;				\
374           const GLchan *tex11 = tex10 + COMPS;				\
375           if (t == info->tmask) {					\
376              tex10 -= info->tsize;					\
377              tex11 -= info->tsize;					\
378           }								\
379           if (s == info->smask) {					\
380              tex01 -= info->tbytesline;				\
381              tex11 -= info->tbytesline;				\
382           }								\
383           DO_TEX;							\
384           span->red += span->redStep;					\
385	   span->green += span->greenStep;				\
386           span->blue += span->blueStep;				\
387	   span->alpha += span->alphaStep;				\
388	   span->intTex[0] += span->intTexStep[0];			\
389	   span->intTex[1] += span->intTexStep[1];			\
390           dest += 4;							\
391	}
392
393
394   GLuint i;
395   GLchan *dest = span->array->rgba[0];
396
397   span->intTex[0] -= FIXED_HALF;
398   span->intTex[1] -= FIXED_HALF;
399   switch (info->filter) {
400   case GL_NEAREST:
401      switch (info->format) {
402      case GL_RGB:
403         switch (info->envmode) {
404         case GL_MODULATE:
405            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
406            break;
407         case GL_DECAL:
408         case GL_REPLACE:
409            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
410            break;
411         case GL_BLEND:
412            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
413            break;
414         case GL_ADD:
415            SPAN_NEAREST(NEAREST_RGB;ADD,3);
416            break;
417         default:
418            _mesa_problem(ctx, "bad tex env mode in SPAN_LINEAR");
419            return;
420         }
421         break;
422      case GL_RGBA:
423         switch(info->envmode) {
424         case GL_MODULATE:
425            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
426            break;
427         case GL_DECAL:
428            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
429            break;
430         case GL_BLEND:
431            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
432            break;
433         case GL_ADD:
434            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
435            break;
436         case GL_REPLACE:
437            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
438            break;
439         default:
440            _mesa_problem(ctx, "bad tex env mode (2) in SPAN_LINEAR");
441            return;
442         }
443         break;
444      }
445      break;
446
447   case GL_LINEAR:
448      span->intTex[0] -= FIXED_HALF;
449      span->intTex[1] -= FIXED_HALF;
450      switch (info->format) {
451      case GL_RGB:
452         switch (info->envmode) {
453         case GL_MODULATE:
454            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
455            break;
456         case GL_DECAL:
457         case GL_REPLACE:
458            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
459            break;
460         case GL_BLEND:
461            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
462            break;
463         case GL_ADD:
464            SPAN_LINEAR(LINEAR_RGB;ADD,3);
465            break;
466         default:
467            _mesa_problem(ctx, "bad tex env mode (3) in SPAN_LINEAR");
468            return;
469         }
470         break;
471      case GL_RGBA:
472         switch (info->envmode) {
473         case GL_MODULATE:
474            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
475            break;
476         case GL_DECAL:
477            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
478            break;
479         case GL_BLEND:
480            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
481            break;
482         case GL_ADD:
483            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
484            break;
485         case GL_REPLACE:
486            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
487            break;
488         default:
489            _mesa_problem(ctx, "bad tex env mode (4) in SPAN_LINEAR");
490            return;
491         }
492         break;
493      }
494      break;
495   }
496   span->interpMask &= ~SPAN_RGBA;
497   ASSERT(span->arrayMask & SPAN_RGBA);
498   _swrast_write_rgba_span(ctx, span);
499
500#undef SPAN_NEAREST
501#undef SPAN_LINEAR
502}
503
504
505
506/*
507 * Render an RGB/RGBA textured triangle without perspective correction.
508 */
509#define NAME affine_textured_triangle
510#define INTERP_Z 1
511#define INTERP_RGB 1
512#define INTERP_ALPHA 1
513#define INTERP_INT_TEX 1
514#define S_SCALE twidth
515#define T_SCALE theight
516
517#define SETUP_CODE							\
518   struct affine_info info;						\
519   struct gl_texture_unit *unit = ctx->Texture.Unit+0;			\
520   struct gl_texture_object *obj = unit->Current2D;			\
521   const GLint b = obj->BaseLevel;					\
522   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
523   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
524   info.texture = (const GLchan *) obj->Image[0][b]->Data;		\
525   info.twidth_log2 = obj->Image[0][b]->WidthLog2;			\
526   info.smask = obj->Image[0][b]->Width - 1;				\
527   info.tmask = obj->Image[0][b]->Height - 1;				\
528   info.format = obj->Image[0][b]->_BaseFormat;				\
529   info.filter = obj->MinFilter;					\
530   info.envmode = unit->EnvMode;					\
531   span.arrayMask |= SPAN_RGBA;						\
532									\
533   if (info.envmode == GL_BLEND) {					\
534      /* potential off-by-one error here? (1.0f -> 2048 -> 0) */	\
535      info.er = FloatToFixed(unit->EnvColor[RCOMP] * CHAN_MAXF);	\
536      info.eg = FloatToFixed(unit->EnvColor[GCOMP] * CHAN_MAXF);	\
537      info.eb = FloatToFixed(unit->EnvColor[BCOMP] * CHAN_MAXF);	\
538      info.ea = FloatToFixed(unit->EnvColor[ACOMP] * CHAN_MAXF);	\
539   }									\
540   if (!info.texture) {							\
541      /* this shouldn't happen */					\
542      return;								\
543   }									\
544									\
545   switch (info.format) {						\
546   case GL_ALPHA:							\
547   case GL_LUMINANCE:							\
548   case GL_INTENSITY:							\
549      info.tbytesline = obj->Image[0][b]->Width;			\
550      break;								\
551   case GL_LUMINANCE_ALPHA:						\
552      info.tbytesline = obj->Image[0][b]->Width * 2;			\
553      break;								\
554   case GL_RGB:								\
555      info.tbytesline = obj->Image[0][b]->Width * 3;			\
556      break;								\
557   case GL_RGBA:							\
558      info.tbytesline = obj->Image[0][b]->Width * 4;			\
559      break;								\
560   default:								\
561      _mesa_problem(NULL, "Bad texture format in affine_texture_triangle");\
562      return;								\
563   }									\
564   info.tsize = obj->Image[0][b]->Height * info.tbytesline;
565
566#define RENDER_SPAN( span )   affine_span(ctx, &span, &info);
567
568#include "s_tritemp.h"
569
570
571
572struct persp_info
573{
574   GLenum filter;
575   GLenum format;
576   GLenum envmode;
577   GLint smask, tmask;
578   GLint twidth_log2;
579   const GLchan *texture;
580   GLfixed er, eg, eb, ea;   /* texture env color */
581   GLint tbytesline, tsize;
582};
583
584
585static INLINE void
586fast_persp_span(GLcontext *ctx, SWspan *span,
587		struct persp_info *info)
588{
589   GLchan sample[4];  /* the filtered texture sample */
590
591  /* Instead of defining a function for each mode, a test is done
592   * between the outer and inner loops. This is to reduce code size
593   * and complexity. Observe that an optimizing compiler kills
594   * unused variables (for instance tf,sf,ti,si in case of GL_NEAREST).
595   */
596#define SPAN_NEAREST(DO_TEX,COMP)					\
597	for (i = 0; i < span->end; i++) {				\
598           GLdouble invQ = tex_coord[2] ?				\
599                                 (1.0 / tex_coord[2]) : 1.0;            \
600           GLfloat s_tmp = (GLfloat) (tex_coord[0] * invQ);		\
601           GLfloat t_tmp = (GLfloat) (tex_coord[1] * invQ);		\
602           GLint s = IFLOOR(s_tmp) & info->smask;	        	\
603           GLint t = IFLOOR(t_tmp) & info->tmask;	        	\
604           GLint pos = (t << info->twidth_log2) + s;			\
605           const GLchan *tex00 = info->texture + COMP * pos;		\
606           DO_TEX;							\
607           span->red += span->redStep;					\
608	   span->green += span->greenStep;				\
609           span->blue += span->blueStep;				\
610	   span->alpha += span->alphaStep;				\
611	   tex_coord[0] += tex_step[0];					\
612	   tex_coord[1] += tex_step[1];					\
613	   tex_coord[2] += tex_step[2];					\
614           dest += 4;							\
615	}
616
617#define SPAN_LINEAR(DO_TEX,COMP)					\
618	for (i = 0; i < span->end; i++) {				\
619           GLdouble invQ = tex_coord[2] ?				\
620                                 (1.0 / tex_coord[2]) : 1.0;            \
621           const GLfloat s_tmp = (GLfloat) (tex_coord[0] * invQ);	\
622           const GLfloat t_tmp = (GLfloat) (tex_coord[1] * invQ);	\
623           const GLfixed s_fix = FloatToFixed(s_tmp) - FIXED_HALF;	\
624           const GLfixed t_fix = FloatToFixed(t_tmp) - FIXED_HALF;      \
625           const GLint s = FixedToInt(FixedFloor(s_fix)) & info->smask;	\
626           const GLint t = FixedToInt(FixedFloor(t_fix)) & info->tmask;	\
627           const GLfixed sf = s_fix & FIXED_FRAC_MASK;			\
628           const GLfixed tf = t_fix & FIXED_FRAC_MASK;			\
629           const GLint pos = (t << info->twidth_log2) + s;		\
630           const GLchan *tex00 = info->texture + COMP * pos;		\
631           const GLchan *tex10 = tex00 + info->tbytesline;		\
632           const GLchan *tex01 = tex00 + COMP;				\
633           const GLchan *tex11 = tex10 + COMP;				\
634           if (t == info->tmask) {					\
635              tex10 -= info->tsize;					\
636              tex11 -= info->tsize;					\
637           }								\
638           if (s == info->smask) {					\
639              tex01 -= info->tbytesline;				\
640              tex11 -= info->tbytesline;				\
641           }								\
642           DO_TEX;							\
643           span->red   += span->redStep;				\
644	   span->green += span->greenStep;				\
645           span->blue  += span->blueStep;				\
646	   span->alpha += span->alphaStep;				\
647	   tex_coord[0] += tex_step[0];					\
648	   tex_coord[1] += tex_step[1];					\
649	   tex_coord[2] += tex_step[2];					\
650           dest += 4;							\
651	}
652
653   GLuint i;
654   GLfloat tex_coord[3], tex_step[3];
655   GLchan *dest = span->array->rgba[0];
656
657   const GLuint savedTexEnable = ctx->Texture._EnabledUnits;
658   ctx->Texture._EnabledUnits = 0;
659
660   tex_coord[0] = span->attrStart[FRAG_ATTRIB_TEX0][0]  * (info->smask + 1);
661   tex_step[0] = span->attrStepX[FRAG_ATTRIB_TEX0][0] * (info->smask + 1);
662   tex_coord[1] = span->attrStart[FRAG_ATTRIB_TEX0][1] * (info->tmask + 1);
663   tex_step[1] = span->attrStepX[FRAG_ATTRIB_TEX0][1] * (info->tmask + 1);
664   /* span->attrStart[FRAG_ATTRIB_TEX0][2] only if 3D-texturing, here only 2D */
665   tex_coord[2] = span->attrStart[FRAG_ATTRIB_TEX0][3];
666   tex_step[2] = span->attrStepX[FRAG_ATTRIB_TEX0][3];
667
668   switch (info->filter) {
669   case GL_NEAREST:
670      switch (info->format) {
671      case GL_RGB:
672         switch (info->envmode) {
673         case GL_MODULATE:
674            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
675            break;
676         case GL_DECAL:
677         case GL_REPLACE:
678            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
679            break;
680         case GL_BLEND:
681            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
682            break;
683         case GL_ADD:
684            SPAN_NEAREST(NEAREST_RGB;ADD,3);
685            break;
686         default:
687            _mesa_problem(ctx, "bad tex env mode (5) in SPAN_LINEAR");
688            return;
689         }
690         break;
691      case GL_RGBA:
692         switch(info->envmode) {
693         case GL_MODULATE:
694            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
695            break;
696         case GL_DECAL:
697            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
698            break;
699         case GL_BLEND:
700            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
701            break;
702         case GL_ADD:
703            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
704            break;
705         case GL_REPLACE:
706            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
707            break;
708         default:
709            _mesa_problem(ctx, "bad tex env mode (6) in SPAN_LINEAR");
710            return;
711         }
712         break;
713      }
714      break;
715
716   case GL_LINEAR:
717      switch (info->format) {
718      case GL_RGB:
719         switch (info->envmode) {
720         case GL_MODULATE:
721            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
722            break;
723         case GL_DECAL:
724         case GL_REPLACE:
725            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
726            break;
727         case GL_BLEND:
728            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
729            break;
730         case GL_ADD:
731            SPAN_LINEAR(LINEAR_RGB;ADD,3);
732            break;
733         default:
734            _mesa_problem(ctx, "bad tex env mode (7) in SPAN_LINEAR");
735            return;
736         }
737         break;
738      case GL_RGBA:
739         switch (info->envmode) {
740         case GL_MODULATE:
741            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
742            break;
743         case GL_DECAL:
744            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
745            break;
746         case GL_BLEND:
747            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
748            break;
749         case GL_ADD:
750            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
751            break;
752         case GL_REPLACE:
753            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
754            break;
755         default:
756            _mesa_problem(ctx, "bad tex env mode (8) in SPAN_LINEAR");
757            return;
758         }
759         break;
760      }
761      break;
762   }
763
764   ASSERT(span->arrayMask & SPAN_RGBA);
765   _swrast_write_rgba_span(ctx, span);
766
767#undef SPAN_NEAREST
768#undef SPAN_LINEAR
769
770   /* restore state */
771   ctx->Texture._EnabledUnits = savedTexEnable;
772}
773
774
775/*
776 * Render an perspective corrected RGB/RGBA textured triangle.
777 * The Q (aka V in Mesa) coordinate must be zero such that the divide
778 * by interpolated Q/W comes out right.
779 *
780 */
781#define NAME persp_textured_triangle
782#define INTERP_Z 1
783#define INTERP_RGB 1
784#define INTERP_ALPHA 1
785#define INTERP_ATTRIBS 1
786
787#define SETUP_CODE							\
788   struct persp_info info;						\
789   const struct gl_texture_unit *unit = ctx->Texture.Unit+0;		\
790   const struct gl_texture_object *obj = unit->Current2D;		\
791   const GLint b = obj->BaseLevel;					\
792   info.texture = (const GLchan *) obj->Image[0][b]->Data;		\
793   info.twidth_log2 = obj->Image[0][b]->WidthLog2;			\
794   info.smask = obj->Image[0][b]->Width - 1;				\
795   info.tmask = obj->Image[0][b]->Height - 1;				\
796   info.format = obj->Image[0][b]->_BaseFormat;				\
797   info.filter = obj->MinFilter;					\
798   info.envmode = unit->EnvMode;					\
799									\
800   if (info.envmode == GL_BLEND) {					\
801      /* potential off-by-one error here? (1.0f -> 2048 -> 0) */	\
802      info.er = FloatToFixed(unit->EnvColor[RCOMP] * CHAN_MAXF);	\
803      info.eg = FloatToFixed(unit->EnvColor[GCOMP] * CHAN_MAXF);	\
804      info.eb = FloatToFixed(unit->EnvColor[BCOMP] * CHAN_MAXF);	\
805      info.ea = FloatToFixed(unit->EnvColor[ACOMP] * CHAN_MAXF);	\
806   }									\
807   if (!info.texture) {							\
808      /* this shouldn't happen */					\
809      return;								\
810   }									\
811									\
812   switch (info.format) {						\
813   case GL_ALPHA:							\
814   case GL_LUMINANCE:							\
815   case GL_INTENSITY:							\
816      info.tbytesline = obj->Image[0][b]->Width;			\
817      break;								\
818   case GL_LUMINANCE_ALPHA:						\
819      info.tbytesline = obj->Image[0][b]->Width * 2;			\
820      break;								\
821   case GL_RGB:								\
822      info.tbytesline = obj->Image[0][b]->Width * 3;			\
823      break;								\
824   case GL_RGBA:							\
825      info.tbytesline = obj->Image[0][b]->Width * 4;			\
826      break;								\
827   default:								\
828      _mesa_problem(NULL, "Bad texture format in persp_textured_triangle");\
829      return;								\
830   }									\
831   info.tsize = obj->Image[0][b]->Height * info.tbytesline;
832
833#define RENDER_SPAN( span )			\
834   span.interpMask &= ~SPAN_RGBA;		\
835   span.arrayMask |= SPAN_RGBA;			\
836   fast_persp_span(ctx, &span, &info);
837
838#include "s_tritemp.h"
839
840#endif /*CHAN_TYPE != GL_FLOAT*/
841
842
843
844/*
845 * Render an RGBA triangle with arbitrary attributes.
846 */
847#define NAME general_triangle
848#define INTERP_Z 1
849#define INTERP_RGB 1
850#define INTERP_ALPHA 1
851#define INTERP_ATTRIBS 1
852#define RENDER_SPAN( span )   _swrast_write_rgba_span(ctx, &span);
853#include "s_tritemp.h"
854
855
856
857
858/*
859 * Special tri function for occlusion testing
860 */
861#define NAME occlusion_zless_triangle
862#define INTERP_Z 1
863#define SETUP_CODE							\
864   struct gl_renderbuffer *rb = ctx->DrawBuffer->_DepthBuffer;		\
865   struct gl_query_object *q = ctx->Query.CurrentOcclusionObject;	\
866   ASSERT(ctx->Depth.Test);						\
867   ASSERT(!ctx->Depth.Mask);						\
868   ASSERT(ctx->Depth.Func == GL_LESS);					\
869   if (!q) {								\
870      return;								\
871   }
872#define RENDER_SPAN( span )						\
873   if (rb->DepthBits <= 16) {						\
874      GLuint i;								\
875      const GLushort *zRow = (const GLushort *)				\
876         rb->GetPointer(ctx, rb, span.x, span.y);			\
877      for (i = 0; i < span.end; i++) {					\
878         GLuint z = FixedToDepth(span.z);				\
879         if (z < zRow[i]) {						\
880            q->Result++;						\
881         }								\
882         span.z += span.zStep;						\
883      }									\
884   }									\
885   else {								\
886      GLuint i;								\
887      const GLuint *zRow = (const GLuint *)				\
888         rb->GetPointer(ctx, rb, span.x, span.y);			\
889      for (i = 0; i < span.end; i++) {					\
890         if ((GLuint)span.z < zRow[i]) {				\
891            q->Result++;						\
892         }								\
893         span.z += span.zStep;						\
894      }									\
895   }
896#include "s_tritemp.h"
897
898
899
900static void
901nodraw_triangle( GLcontext *ctx,
902                 const SWvertex *v0,
903                 const SWvertex *v1,
904                 const SWvertex *v2 )
905{
906   (void) (ctx && v0 && v1 && v2);
907}
908
909
910/*
911 * This is used when separate specular color is enabled, but not
912 * texturing.  We add the specular color to the primary color,
913 * draw the triangle, then restore the original primary color.
914 * Inefficient, but seldom needed.
915 */
916void
917_swrast_add_spec_terms_triangle(GLcontext *ctx, const SWvertex *v0,
918                                const SWvertex *v1, const SWvertex *v2)
919{
920   SWvertex *ncv0 = (SWvertex *)v0; /* drop const qualifier */
921   SWvertex *ncv1 = (SWvertex *)v1;
922   SWvertex *ncv2 = (SWvertex *)v2;
923   GLfloat rSum, gSum, bSum;
924   GLchan cSave[3][4];
925
926   /* save original colors */
927   COPY_CHAN4( cSave[0], ncv0->color );
928   COPY_CHAN4( cSave[1], ncv1->color );
929   COPY_CHAN4( cSave[2], ncv2->color );
930   /* sum v0 */
931   rSum = CHAN_TO_FLOAT(ncv0->color[0]) + ncv0->attrib[FRAG_ATTRIB_COL1][0];
932   gSum = CHAN_TO_FLOAT(ncv0->color[1]) + ncv0->attrib[FRAG_ATTRIB_COL1][1];
933   bSum = CHAN_TO_FLOAT(ncv0->color[2]) + ncv0->attrib[FRAG_ATTRIB_COL1][2];
934   UNCLAMPED_FLOAT_TO_CHAN(ncv0->color[0], rSum);
935   UNCLAMPED_FLOAT_TO_CHAN(ncv0->color[1], gSum);
936   UNCLAMPED_FLOAT_TO_CHAN(ncv0->color[2], bSum);
937   /* sum v1 */
938   rSum = CHAN_TO_FLOAT(ncv1->color[0]) + ncv1->attrib[FRAG_ATTRIB_COL1][0];
939   gSum = CHAN_TO_FLOAT(ncv1->color[1]) + ncv1->attrib[FRAG_ATTRIB_COL1][1];
940   bSum = CHAN_TO_FLOAT(ncv1->color[2]) + ncv1->attrib[FRAG_ATTRIB_COL1][2];
941   UNCLAMPED_FLOAT_TO_CHAN(ncv1->color[0], rSum);
942   UNCLAMPED_FLOAT_TO_CHAN(ncv1->color[1], gSum);
943   UNCLAMPED_FLOAT_TO_CHAN(ncv1->color[2], bSum);
944   /* sum v2 */
945   rSum = CHAN_TO_FLOAT(ncv2->color[0]) + ncv2->attrib[FRAG_ATTRIB_COL1][0];
946   gSum = CHAN_TO_FLOAT(ncv2->color[1]) + ncv2->attrib[FRAG_ATTRIB_COL1][1];
947   bSum = CHAN_TO_FLOAT(ncv2->color[2]) + ncv2->attrib[FRAG_ATTRIB_COL1][2];
948   UNCLAMPED_FLOAT_TO_CHAN(ncv2->color[0], rSum);
949   UNCLAMPED_FLOAT_TO_CHAN(ncv2->color[1], gSum);
950   UNCLAMPED_FLOAT_TO_CHAN(ncv2->color[2], bSum);
951   /* draw */
952   SWRAST_CONTEXT(ctx)->SpecTriangle( ctx, ncv0, ncv1, ncv2 );
953   /* restore original colors */
954   COPY_CHAN4( ncv0->color, cSave[0] );
955   COPY_CHAN4( ncv1->color, cSave[1] );
956   COPY_CHAN4( ncv2->color, cSave[2] );
957}
958
959
960
961#ifdef DEBUG
962
963/* record the current triangle function name */
964const char *_mesa_triFuncName = NULL;
965
966#define USE(triFunc)				\
967do {						\
968    _mesa_triFuncName = #triFunc;		\
969    /*printf("%s\n", _mesa_triFuncName);*/	\
970    swrast->Triangle = triFunc;			\
971} while (0)
972
973#else
974
975#define USE(triFunc)  swrast->Triangle = triFunc;
976
977#endif
978
979
980
981
982/*
983 * Determine which triangle rendering function to use given the current
984 * rendering context.
985 *
986 * Please update the summary flag _SWRAST_NEW_TRIANGLE if you add or
987 * remove tests to this code.
988 */
989void
990_swrast_choose_triangle( GLcontext *ctx )
991{
992   SWcontext *swrast = SWRAST_CONTEXT(ctx);
993   const GLboolean rgbmode = ctx->Visual.rgbMode;
994
995   if (ctx->Polygon.CullFlag &&
996       ctx->Polygon.CullFaceMode == GL_FRONT_AND_BACK) {
997      USE(nodraw_triangle);
998      return;
999   }
1000
1001   if (ctx->RenderMode==GL_RENDER) {
1002
1003      if (ctx->Polygon.SmoothFlag) {
1004         _swrast_set_aa_triangle_function(ctx);
1005         ASSERT(swrast->Triangle);
1006         return;
1007      }
1008
1009      /* special case for occlusion testing */
1010      if (ctx->Query.CurrentOcclusionObject &&
1011          ctx->Depth.Test &&
1012          ctx->Depth.Mask == GL_FALSE &&
1013          ctx->Depth.Func == GL_LESS &&
1014          !ctx->Stencil.Enabled) {
1015         if ((rgbmode &&
1016              ctx->Color.ColorMask[0] == 0 &&
1017              ctx->Color.ColorMask[1] == 0 &&
1018              ctx->Color.ColorMask[2] == 0 &&
1019              ctx->Color.ColorMask[3] == 0)
1020             ||
1021             (!rgbmode && ctx->Color.IndexMask == 0)) {
1022            USE(occlusion_zless_triangle);
1023            return;
1024         }
1025      }
1026
1027      if (!rgbmode) {
1028         USE(ci_triangle);
1029         return;
1030      }
1031
1032      /*
1033       * XXX should examine swrast->_ActiveAttribMask to determine what
1034       * needs to be interpolated.
1035       */
1036      if (ctx->Texture._EnabledCoordUnits ||
1037          ctx->FragmentProgram._Current ||
1038          ctx->ATIFragmentShader._Enabled ||
1039          NEED_SECONDARY_COLOR(ctx) ||
1040          swrast->_FogEnabled) {
1041         /* Ugh, we do a _lot_ of tests to pick the best textured tri func */
1042         const struct gl_texture_object *texObj2D;
1043         const struct gl_texture_image *texImg;
1044         GLenum minFilter, magFilter, envMode;
1045         GLint format;
1046         texObj2D = ctx->Texture.Unit[0].Current2D;
1047         texImg = texObj2D ? texObj2D->Image[0][texObj2D->BaseLevel] : NULL;
1048         format = texImg ? texImg->TexFormat->MesaFormat : -1;
1049         minFilter = texObj2D ? texObj2D->MinFilter : (GLenum) 0;
1050         magFilter = texObj2D ? texObj2D->MagFilter : (GLenum) 0;
1051         envMode = ctx->Texture.Unit[0].EnvMode;
1052
1053         /* First see if we can use an optimized 2-D texture function */
1054         if (ctx->Texture._EnabledCoordUnits == 0x1
1055             && !ctx->FragmentProgram._Current
1056             && !ctx->ATIFragmentShader._Enabled
1057             && ctx->Texture.Unit[0]._ReallyEnabled == TEXTURE_2D_BIT
1058             && texObj2D->WrapS == GL_REPEAT
1059             && texObj2D->WrapT == GL_REPEAT
1060             && texImg->_IsPowerOfTwo
1061             && texImg->Border == 0
1062             && texImg->Width == texImg->RowStride
1063             && (format == MESA_FORMAT_RGB || format == MESA_FORMAT_RGBA)
1064             && minFilter == magFilter
1065             && ctx->Light.Model.ColorControl == GL_SINGLE_COLOR
1066             && !swrast->_FogEnabled
1067             && ctx->Texture.Unit[0].EnvMode != GL_COMBINE_EXT) {
1068	    if (ctx->Hint.PerspectiveCorrection==GL_FASTEST) {
1069	       if (minFilter == GL_NEAREST
1070		   && format == MESA_FORMAT_RGB
1071		   && (envMode == GL_REPLACE || envMode == GL_DECAL)
1072		   && ((swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)
1073			&& ctx->Depth.Func == GL_LESS
1074			&& ctx->Depth.Mask == GL_TRUE)
1075		       || swrast->_RasterMask == TEXTURE_BIT)
1076		   && ctx->Polygon.StippleFlag == GL_FALSE
1077                   && ctx->DrawBuffer->Visual.depthBits <= 16) {
1078		  if (swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)) {
1079		     USE(simple_z_textured_triangle);
1080		  }
1081		  else {
1082		     USE(simple_textured_triangle);
1083		  }
1084	       }
1085	       else {
1086#if CHAN_BITS != 8
1087                  USE(general_triangle);
1088#else
1089                  USE(affine_textured_triangle);
1090#endif
1091	       }
1092	    }
1093	    else {
1094#if CHAN_BITS != 8
1095               USE(general_triangle);
1096#else
1097               USE(persp_textured_triangle);
1098#endif
1099	    }
1100	 }
1101         else {
1102            /* general case textured triangles */
1103            USE(general_triangle);
1104         }
1105      }
1106      else {
1107         ASSERT(!swrast->_FogEnabled);
1108         ASSERT(!NEED_SECONDARY_COLOR(ctx));
1109	 if (ctx->Light.ShadeModel==GL_SMOOTH) {
1110	    /* smooth shaded, no texturing, stippled or some raster ops */
1111#if CHAN_BITS != 8
1112               USE(general_triangle);
1113#else
1114               USE(smooth_rgba_triangle);
1115#endif
1116	 }
1117	 else {
1118	    /* flat shaded, no texturing, stippled or some raster ops */
1119#if CHAN_BITS != 8
1120            USE(general_triangle);
1121#else
1122            USE(flat_rgba_triangle);
1123#endif
1124	 }
1125      }
1126   }
1127   else if (ctx->RenderMode==GL_FEEDBACK) {
1128      USE(_swrast_feedback_triangle);
1129   }
1130   else {
1131      /* GL_SELECT mode */
1132      USE(_swrast_select_triangle);
1133   }
1134}
1135