s_triangle.c revision 4003bde6fffc3e5b9e1a115ba952b988dffb099a
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->win[0] - v0->win[0];
56   GLfloat ey = v1->win[1] - v0->win[1];
57   GLfloat fx = v2->win[0] - v0->win[0];
58   GLfloat fy = v2->win[1] - v0->win[1];
59   GLfloat c = ex*fy-ey*fx;
60
61   if (c * SWRAST_CONTEXT(ctx)->_BackfaceSign > 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_FOG 1
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 INTERP_FOG 1
87#define SETUP_CODE				\
88   ASSERT(ctx->Texture._EnabledCoordUnits == 0);\
89   ASSERT(ctx->Light.ShadeModel==GL_FLAT);	\
90   span.interpMask |= SPAN_RGBA;		\
91   span.red = ChanToFixed(v2->color[0]);	\
92   span.green = ChanToFixed(v2->color[1]);	\
93   span.blue = ChanToFixed(v2->color[2]);	\
94   span.alpha = ChanToFixed(v2->color[3]);	\
95   span.redStep = 0;				\
96   span.greenStep = 0;				\
97   span.blueStep = 0;				\
98   span.alphaStep = 0;
99#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
100#include "s_tritemp.h"
101
102
103
104/*
105 * Render a smooth-shaded RGBA triangle.
106 */
107#define NAME smooth_rgba_triangle
108#define INTERP_Z 1
109#define INTERP_FOG 1
110#define INTERP_RGB 1
111#define INTERP_ALPHA 1
112#define SETUP_CODE				\
113   {						\
114      /* texturing must be off */		\
115      ASSERT(ctx->Texture._EnabledCoordUnits == 0);	\
116      ASSERT(ctx->Light.ShadeModel==GL_SMOOTH);	\
117   }
118#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
119#include "s_tritemp.h"
120
121
122
123/*
124 * Render an RGB, GL_DECAL, textured triangle.
125 * Interpolate S,T only w/out mipmapping or perspective correction.
126 *
127 * No fog.  No depth testing.
128 */
129#define NAME simple_textured_triangle
130#define INTERP_INT_TEX 1
131#define S_SCALE twidth
132#define T_SCALE theight
133
134#define SETUP_CODE							\
135   struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0][0];\
136   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
137   const GLint b = obj->BaseLevel;					\
138   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
139   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
140   const GLint twidth_log2 = obj->Image[0][b]->WidthLog2;		\
141   const GLchan *texture = (const GLchan *) obj->Image[0][b]->Data;	\
142   const GLint smask = obj->Image[0][b]->Width - 1;			\
143   const GLint tmask = obj->Image[0][b]->Height - 1;			\
144   if (!texture) {							\
145      /* this shouldn't happen */					\
146      return;								\
147   }
148
149#define RENDER_SPAN( span )						\
150   GLuint i;								\
151   GLchan rgb[MAX_WIDTH][3];						\
152   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
153   span.intTex[1] -= FIXED_HALF;					\
154   for (i = 0; i < span.end; i++) {					\
155      GLint s = FixedToInt(span.intTex[0]) & smask;			\
156      GLint t = FixedToInt(span.intTex[1]) & tmask;			\
157      GLint pos = (t << twidth_log2) + s;				\
158      pos = pos + pos + pos;  /* multiply by 3 */			\
159      rgb[i][RCOMP] = texture[pos];					\
160      rgb[i][GCOMP] = texture[pos+1];					\
161      rgb[i][BCOMP] = texture[pos+2];					\
162      span.intTex[0] += span.intTexStep[0];				\
163      span.intTex[1] += span.intTexStep[1];				\
164   }									\
165   rb->PutRowRGB(ctx, rb, span.end, span.x, span.y, rgb, NULL);
166
167#include "s_tritemp.h"
168
169
170
171/*
172 * Render an RGB, GL_DECAL, textured triangle.
173 * Interpolate S,T, GL_LESS depth test, w/out mipmapping or
174 * perspective correction.
175 * Depth buffer bits must be <= sizeof(DEFAULT_SOFTWARE_DEPTH_TYPE)
176 *
177 * No fog.
178 */
179#define NAME simple_z_textured_triangle
180#define INTERP_Z 1
181#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
182#define INTERP_INT_TEX 1
183#define S_SCALE twidth
184#define T_SCALE theight
185
186#define SETUP_CODE							\
187   struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0][0];\
188   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
189   const GLint b = obj->BaseLevel;					\
190   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
191   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
192   const GLint twidth_log2 = obj->Image[0][b]->WidthLog2;		\
193   const GLchan *texture = (const GLchan *) obj->Image[0][b]->Data;	\
194   const GLint smask = obj->Image[0][b]->Width - 1;			\
195   const GLint tmask = obj->Image[0][b]->Height - 1;			\
196   if (!texture) {							\
197      /* this shouldn't happen */					\
198      return;								\
199   }
200
201#define RENDER_SPAN( span )						\
202   GLuint i;				    				\
203   GLchan rgb[MAX_WIDTH][3];						\
204   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
205   span.intTex[1] -= FIXED_HALF;					\
206   for (i = 0; i < span.end; i++) {					\
207      const GLuint z = FixedToDepth(span.z);				\
208      if (z < zRow[i]) {						\
209         GLint s = FixedToInt(span.intTex[0]) & smask;			\
210         GLint t = FixedToInt(span.intTex[1]) & tmask;			\
211         GLint pos = (t << twidth_log2) + s;				\
212         pos = pos + pos + pos;  /* multiply by 3 */			\
213         rgb[i][RCOMP] = texture[pos];					\
214         rgb[i][GCOMP] = texture[pos+1];				\
215         rgb[i][BCOMP] = texture[pos+2];				\
216         zRow[i] = z;							\
217         span.array->mask[i] = 1;					\
218      }									\
219      else {								\
220         span.array->mask[i] = 0;					\
221      }									\
222      span.intTex[0] += span.intTexStep[0];				\
223      span.intTex[1] += span.intTexStep[1];				\
224      span.z += span.zStep;						\
225   }									\
226   rb->PutRowRGB(ctx, rb, span.end, span.x, span.y, rgb, span.array->mask);
227
228#include "s_tritemp.h"
229
230
231
232#if CHAN_TYPE != GL_FLOAT
233
234struct affine_info
235{
236   GLenum filter;
237   GLenum format;
238   GLenum envmode;
239   GLint smask, tmask;
240   GLint twidth_log2;
241   const GLchan *texture;
242   GLfixed er, eg, eb, ea;
243   GLint tbytesline, tsize;
244};
245
246
247static INLINE GLint
248ilerp(GLint t, GLint a, GLint b)
249{
250   return a + ((t * (b - a)) >> FIXED_SHIFT);
251}
252
253static INLINE GLint
254ilerp_2d(GLint ia, GLint ib, GLint v00, GLint v10, GLint v01, GLint v11)
255{
256   const GLint temp0 = ilerp(ia, v00, v10);
257   const GLint temp1 = ilerp(ia, v01, v11);
258   return ilerp(ib, temp0, temp1);
259}
260
261
262/* This function can handle GL_NEAREST or GL_LINEAR sampling of 2D RGB or RGBA
263 * textures with GL_REPLACE, GL_MODULATE, GL_BLEND, GL_DECAL or GL_ADD
264 * texture env modes.
265 */
266static INLINE void
267affine_span(GLcontext *ctx, SWspan *span,
268            struct affine_info *info)
269{
270   GLchan sample[4];  /* the filtered texture sample */
271
272   /* Instead of defining a function for each mode, a test is done
273    * between the outer and inner loops. This is to reduce code size
274    * and complexity. Observe that an optimizing compiler kills
275    * unused variables (for instance tf,sf,ti,si in case of GL_NEAREST).
276    */
277
278#define NEAREST_RGB			\
279   sample[RCOMP] = tex00[RCOMP];	\
280   sample[GCOMP] = tex00[GCOMP];	\
281   sample[BCOMP] = tex00[BCOMP];	\
282   sample[ACOMP] = CHAN_MAX
283
284#define LINEAR_RGB							\
285   sample[RCOMP] = ilerp_2d(sf, tf, tex00[0], tex01[0], tex10[0], tex11[0]);\
286   sample[GCOMP] = ilerp_2d(sf, tf, tex00[1], tex01[1], tex10[1], tex11[1]);\
287   sample[BCOMP] = ilerp_2d(sf, tf, tex00[2], tex01[2], tex10[2], tex11[2]);\
288   sample[ACOMP] = CHAN_MAX;
289
290#define NEAREST_RGBA  COPY_CHAN4(sample, tex00)
291
292#define LINEAR_RGBA							\
293   sample[RCOMP] = ilerp_2d(sf, tf, tex00[0], tex01[0], tex10[0], tex11[0]);\
294   sample[GCOMP] = ilerp_2d(sf, tf, tex00[1], tex01[1], tex10[1], tex11[1]);\
295   sample[BCOMP] = ilerp_2d(sf, tf, tex00[2], tex01[2], tex10[2], tex11[2]);\
296   sample[ACOMP] = ilerp_2d(sf, tf, tex00[3], tex01[3], tex10[3], tex11[3])
297
298#define MODULATE							  \
299   dest[RCOMP] = span->red   * (sample[RCOMP] + 1u) >> (FIXED_SHIFT + 8); \
300   dest[GCOMP] = span->green * (sample[GCOMP] + 1u) >> (FIXED_SHIFT + 8); \
301   dest[BCOMP] = span->blue  * (sample[BCOMP] + 1u) >> (FIXED_SHIFT + 8); \
302   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1u) >> (FIXED_SHIFT + 8)
303
304#define DECAL								\
305   dest[RCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->red +		\
306               ((sample[ACOMP] + 1) * sample[RCOMP] << FIXED_SHIFT))	\
307               >> (FIXED_SHIFT + 8);					\
308   dest[GCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->green +		\
309               ((sample[ACOMP] + 1) * sample[GCOMP] << FIXED_SHIFT))	\
310               >> (FIXED_SHIFT + 8);					\
311   dest[BCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->blue +		\
312               ((sample[ACOMP] + 1) * sample[BCOMP] << FIXED_SHIFT))	\
313               >> (FIXED_SHIFT + 8);					\
314   dest[ACOMP] = FixedToInt(span->alpha)
315
316#define BLEND								\
317   dest[RCOMP] = ((CHAN_MAX - sample[RCOMP]) * span->red		\
318               + (sample[RCOMP] + 1) * info->er) >> (FIXED_SHIFT + 8);	\
319   dest[GCOMP] = ((CHAN_MAX - sample[GCOMP]) * span->green		\
320               + (sample[GCOMP] + 1) * info->eg) >> (FIXED_SHIFT + 8);	\
321   dest[BCOMP] = ((CHAN_MAX - sample[BCOMP]) * span->blue		\
322               + (sample[BCOMP] + 1) * info->eb) >> (FIXED_SHIFT + 8);	\
323   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8)
324
325#define REPLACE  COPY_CHAN4(dest, sample)
326
327#define ADD								\
328   {									\
329      GLint rSum = FixedToInt(span->red)   + (GLint) sample[RCOMP];	\
330      GLint gSum = FixedToInt(span->green) + (GLint) sample[GCOMP];	\
331      GLint bSum = FixedToInt(span->blue)  + (GLint) sample[BCOMP];	\
332      dest[RCOMP] = MIN2(rSum, CHAN_MAX);				\
333      dest[GCOMP] = MIN2(gSum, CHAN_MAX);				\
334      dest[BCOMP] = MIN2(bSum, CHAN_MAX);				\
335      dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8); \
336  }
337
338/* shortcuts */
339
340#define NEAREST_RGB_REPLACE		\
341   NEAREST_RGB;				\
342   dest[0] = sample[0];			\
343   dest[1] = sample[1];			\
344   dest[2] = sample[2];			\
345   dest[3] = FixedToInt(span->alpha);
346
347#define NEAREST_RGBA_REPLACE  COPY_CHAN4(dest, tex00)
348
349#define SPAN_NEAREST(DO_TEX, COMPS)					\
350	for (i = 0; i < span->end; i++) {				\
351           /* Isn't it necessary to use FixedFloor below?? */		\
352           GLint s = FixedToInt(span->intTex[0]) & info->smask;		\
353           GLint t = FixedToInt(span->intTex[1]) & info->tmask;		\
354           GLint pos = (t << info->twidth_log2) + s;			\
355           const GLchan *tex00 = info->texture + COMPS * pos;		\
356           DO_TEX;							\
357           span->red += span->redStep;					\
358	   span->green += span->greenStep;				\
359           span->blue += span->blueStep;				\
360	   span->alpha += span->alphaStep;				\
361	   span->intTex[0] += span->intTexStep[0];			\
362	   span->intTex[1] += span->intTexStep[1];			\
363           dest += 4;							\
364	}
365
366#define SPAN_LINEAR(DO_TEX, COMPS)					\
367	for (i = 0; i < span->end; i++) {				\
368           /* Isn't it necessary to use FixedFloor below?? */		\
369           const GLint s = FixedToInt(span->intTex[0]) & info->smask;	\
370           const GLint t = FixedToInt(span->intTex[1]) & info->tmask;	\
371           const GLfixed sf = span->intTex[0] & FIXED_FRAC_MASK;	\
372           const GLfixed tf = span->intTex[1] & FIXED_FRAC_MASK;	\
373           const GLint pos = (t << info->twidth_log2) + s;		\
374           const GLchan *tex00 = info->texture + COMPS * pos;		\
375           const GLchan *tex10 = tex00 + info->tbytesline;		\
376           const GLchan *tex01 = tex00 + COMPS;				\
377           const GLchan *tex11 = tex10 + COMPS;				\
378           if (t == info->tmask) {					\
379              tex10 -= info->tsize;					\
380              tex11 -= info->tsize;					\
381           }								\
382           if (s == info->smask) {					\
383              tex01 -= info->tbytesline;				\
384              tex11 -= info->tbytesline;				\
385           }								\
386           DO_TEX;							\
387           span->red += span->redStep;					\
388	   span->green += span->greenStep;				\
389           span->blue += span->blueStep;				\
390	   span->alpha += span->alphaStep;				\
391	   span->intTex[0] += span->intTexStep[0];			\
392	   span->intTex[1] += span->intTexStep[1];			\
393           dest += 4;							\
394	}
395
396
397   GLuint i;
398   GLchan *dest = span->array->rgba[0];
399
400   span->intTex[0] -= FIXED_HALF;
401   span->intTex[1] -= FIXED_HALF;
402   switch (info->filter) {
403   case GL_NEAREST:
404      switch (info->format) {
405      case GL_RGB:
406         switch (info->envmode) {
407         case GL_MODULATE:
408            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
409            break;
410         case GL_DECAL:
411         case GL_REPLACE:
412            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
413            break;
414         case GL_BLEND:
415            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
416            break;
417         case GL_ADD:
418            SPAN_NEAREST(NEAREST_RGB;ADD,3);
419            break;
420         default:
421            _mesa_problem(ctx, "bad tex env mode in SPAN_LINEAR");
422            return;
423         }
424         break;
425      case GL_RGBA:
426         switch(info->envmode) {
427         case GL_MODULATE:
428            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
429            break;
430         case GL_DECAL:
431            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
432            break;
433         case GL_BLEND:
434            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
435            break;
436         case GL_ADD:
437            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
438            break;
439         case GL_REPLACE:
440            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
441            break;
442         default:
443            _mesa_problem(ctx, "bad tex env mode (2) in SPAN_LINEAR");
444            return;
445         }
446         break;
447      }
448      break;
449
450   case GL_LINEAR:
451      span->intTex[0] -= FIXED_HALF;
452      span->intTex[1] -= FIXED_HALF;
453      switch (info->format) {
454      case GL_RGB:
455         switch (info->envmode) {
456         case GL_MODULATE:
457            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
458            break;
459         case GL_DECAL:
460         case GL_REPLACE:
461            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
462            break;
463         case GL_BLEND:
464            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
465            break;
466         case GL_ADD:
467            SPAN_LINEAR(LINEAR_RGB;ADD,3);
468            break;
469         default:
470            _mesa_problem(ctx, "bad tex env mode (3) in SPAN_LINEAR");
471            return;
472         }
473         break;
474      case GL_RGBA:
475         switch (info->envmode) {
476         case GL_MODULATE:
477            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
478            break;
479         case GL_DECAL:
480            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
481            break;
482         case GL_BLEND:
483            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
484            break;
485         case GL_ADD:
486            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
487            break;
488         case GL_REPLACE:
489            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
490            break;
491         default:
492            _mesa_problem(ctx, "bad tex env mode (4) in SPAN_LINEAR");
493            return;
494         }
495         break;
496      }
497      break;
498   }
499   span->interpMask &= ~SPAN_RGBA;
500   ASSERT(span->arrayMask & SPAN_RGBA);
501   _swrast_write_rgba_span(ctx, span);
502
503#undef SPAN_NEAREST
504#undef SPAN_LINEAR
505}
506
507
508
509/*
510 * Render an RGB/RGBA textured triangle without perspective correction.
511 */
512#define NAME affine_textured_triangle
513#define INTERP_Z 1
514#define INTERP_FOG 1
515#define INTERP_RGB 1
516#define INTERP_ALPHA 1
517#define INTERP_INT_TEX 1
518#define S_SCALE twidth
519#define T_SCALE theight
520
521#define SETUP_CODE							\
522   struct affine_info info;						\
523   struct gl_texture_unit *unit = ctx->Texture.Unit+0;			\
524   struct gl_texture_object *obj = unit->Current2D;			\
525   const GLint b = obj->BaseLevel;					\
526   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
527   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
528   info.texture = (const GLchan *) obj->Image[0][b]->Data;		\
529   info.twidth_log2 = obj->Image[0][b]->WidthLog2;			\
530   info.smask = obj->Image[0][b]->Width - 1;				\
531   info.tmask = obj->Image[0][b]->Height - 1;				\
532   info.format = obj->Image[0][b]->_BaseFormat;				\
533   info.filter = obj->MinFilter;					\
534   info.envmode = unit->EnvMode;					\
535   span.arrayMask |= SPAN_RGBA;						\
536									\
537   if (info.envmode == GL_BLEND) {					\
538      /* potential off-by-one error here? (1.0f -> 2048 -> 0) */	\
539      info.er = FloatToFixed(unit->EnvColor[RCOMP] * CHAN_MAXF);	\
540      info.eg = FloatToFixed(unit->EnvColor[GCOMP] * CHAN_MAXF);	\
541      info.eb = FloatToFixed(unit->EnvColor[BCOMP] * CHAN_MAXF);	\
542      info.ea = FloatToFixed(unit->EnvColor[ACOMP] * CHAN_MAXF);	\
543   }									\
544   if (!info.texture) {							\
545      /* this shouldn't happen */					\
546      return;								\
547   }									\
548									\
549   switch (info.format) {						\
550   case GL_ALPHA:							\
551   case GL_LUMINANCE:							\
552   case GL_INTENSITY:							\
553      info.tbytesline = obj->Image[0][b]->Width;			\
554      break;								\
555   case GL_LUMINANCE_ALPHA:						\
556      info.tbytesline = obj->Image[0][b]->Width * 2;			\
557      break;								\
558   case GL_RGB:								\
559      info.tbytesline = obj->Image[0][b]->Width * 3;			\
560      break;								\
561   case GL_RGBA:							\
562      info.tbytesline = obj->Image[0][b]->Width * 4;			\
563      break;								\
564   default:								\
565      _mesa_problem(NULL, "Bad texture format in affine_texture_triangle");\
566      return;								\
567   }									\
568   info.tsize = obj->Image[0][b]->Height * info.tbytesline;
569
570#define RENDER_SPAN( span )   affine_span(ctx, &span, &info);
571
572#include "s_tritemp.h"
573
574
575
576struct persp_info
577{
578   GLenum filter;
579   GLenum format;
580   GLenum envmode;
581   GLint smask, tmask;
582   GLint twidth_log2;
583   const GLchan *texture;
584   GLfixed er, eg, eb, ea;   /* texture env color */
585   GLint tbytesline, tsize;
586};
587
588
589static INLINE void
590fast_persp_span(GLcontext *ctx, SWspan *span,
591		struct persp_info *info)
592{
593   GLchan sample[4];  /* the filtered texture sample */
594
595  /* Instead of defining a function for each mode, a test is done
596   * between the outer and inner loops. This is to reduce code size
597   * and complexity. Observe that an optimizing compiler kills
598   * unused variables (for instance tf,sf,ti,si in case of GL_NEAREST).
599   */
600#define SPAN_NEAREST(DO_TEX,COMP)					\
601	for (i = 0; i < span->end; i++) {				\
602           GLdouble invQ = tex_coord[2] ?				\
603                                 (1.0 / tex_coord[2]) : 1.0;            \
604           GLfloat s_tmp = (GLfloat) (tex_coord[0] * invQ);		\
605           GLfloat t_tmp = (GLfloat) (tex_coord[1] * invQ);		\
606           GLint s = IFLOOR(s_tmp) & info->smask;	        	\
607           GLint t = IFLOOR(t_tmp) & info->tmask;	        	\
608           GLint pos = (t << info->twidth_log2) + s;			\
609           const GLchan *tex00 = info->texture + COMP * pos;		\
610           DO_TEX;							\
611           span->red += span->redStep;					\
612	   span->green += span->greenStep;				\
613           span->blue += span->blueStep;				\
614	   span->alpha += span->alphaStep;				\
615	   tex_coord[0] += tex_step[0];					\
616	   tex_coord[1] += tex_step[1];					\
617	   tex_coord[2] += tex_step[2];					\
618           dest += 4;							\
619	}
620
621#define SPAN_LINEAR(DO_TEX,COMP)					\
622	for (i = 0; i < span->end; i++) {				\
623           GLdouble invQ = tex_coord[2] ?				\
624                                 (1.0 / tex_coord[2]) : 1.0;            \
625           const GLfloat s_tmp = (GLfloat) (tex_coord[0] * invQ);	\
626           const GLfloat t_tmp = (GLfloat) (tex_coord[1] * invQ);	\
627           const GLfixed s_fix = FloatToFixed(s_tmp) - FIXED_HALF;	\
628           const GLfixed t_fix = FloatToFixed(t_tmp) - FIXED_HALF;      \
629           const GLint s = FixedToInt(FixedFloor(s_fix)) & info->smask;	\
630           const GLint t = FixedToInt(FixedFloor(t_fix)) & info->tmask;	\
631           const GLfixed sf = s_fix & FIXED_FRAC_MASK;			\
632           const GLfixed tf = t_fix & FIXED_FRAC_MASK;			\
633           const GLint pos = (t << info->twidth_log2) + s;		\
634           const GLchan *tex00 = info->texture + COMP * pos;		\
635           const GLchan *tex10 = tex00 + info->tbytesline;		\
636           const GLchan *tex01 = tex00 + COMP;				\
637           const GLchan *tex11 = tex10 + COMP;				\
638           if (t == info->tmask) {					\
639              tex10 -= info->tsize;					\
640              tex11 -= info->tsize;					\
641           }								\
642           if (s == info->smask) {					\
643              tex01 -= info->tbytesline;				\
644              tex11 -= info->tbytesline;				\
645           }								\
646           DO_TEX;							\
647           span->red   += span->redStep;				\
648	   span->green += span->greenStep;				\
649           span->blue  += span->blueStep;				\
650	   span->alpha += span->alphaStep;				\
651	   tex_coord[0] += tex_step[0];					\
652	   tex_coord[1] += tex_step[1];					\
653	   tex_coord[2] += tex_step[2];					\
654           dest += 4;							\
655	}
656
657   GLuint i;
658   GLfloat tex_coord[3], tex_step[3];
659   GLchan *dest = span->array->rgba[0];
660
661   const GLuint savedTexEnable = ctx->Texture._EnabledUnits;
662   ctx->Texture._EnabledUnits = 0;
663
664   tex_coord[0] = span->attrStart[FRAG_ATTRIB_TEX0][0]  * (info->smask + 1);
665   tex_step[0] = span->attrStepX[FRAG_ATTRIB_TEX0][0] * (info->smask + 1);
666   tex_coord[1] = span->attrStart[FRAG_ATTRIB_TEX0][1] * (info->tmask + 1);
667   tex_step[1] = span->attrStepX[FRAG_ATTRIB_TEX0][1] * (info->tmask + 1);
668   /* span->attrStart[FRAG_ATTRIB_TEX0][2] only if 3D-texturing, here only 2D */
669   tex_coord[2] = span->attrStart[FRAG_ATTRIB_TEX0][3];
670   tex_step[2] = span->attrStepX[FRAG_ATTRIB_TEX0][3];
671
672   switch (info->filter) {
673   case GL_NEAREST:
674      switch (info->format) {
675      case GL_RGB:
676         switch (info->envmode) {
677         case GL_MODULATE:
678            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
679            break;
680         case GL_DECAL:
681         case GL_REPLACE:
682            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
683            break;
684         case GL_BLEND:
685            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
686            break;
687         case GL_ADD:
688            SPAN_NEAREST(NEAREST_RGB;ADD,3);
689            break;
690         default:
691            _mesa_problem(ctx, "bad tex env mode (5) in SPAN_LINEAR");
692            return;
693         }
694         break;
695      case GL_RGBA:
696         switch(info->envmode) {
697         case GL_MODULATE:
698            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
699            break;
700         case GL_DECAL:
701            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
702            break;
703         case GL_BLEND:
704            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
705            break;
706         case GL_ADD:
707            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
708            break;
709         case GL_REPLACE:
710            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
711            break;
712         default:
713            _mesa_problem(ctx, "bad tex env mode (6) in SPAN_LINEAR");
714            return;
715         }
716         break;
717      }
718      break;
719
720   case GL_LINEAR:
721      switch (info->format) {
722      case GL_RGB:
723         switch (info->envmode) {
724         case GL_MODULATE:
725            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
726            break;
727         case GL_DECAL:
728         case GL_REPLACE:
729            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
730            break;
731         case GL_BLEND:
732            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
733            break;
734         case GL_ADD:
735            SPAN_LINEAR(LINEAR_RGB;ADD,3);
736            break;
737         default:
738            _mesa_problem(ctx, "bad tex env mode (7) in SPAN_LINEAR");
739            return;
740         }
741         break;
742      case GL_RGBA:
743         switch (info->envmode) {
744         case GL_MODULATE:
745            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
746            break;
747         case GL_DECAL:
748            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
749            break;
750         case GL_BLEND:
751            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
752            break;
753         case GL_ADD:
754            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
755            break;
756         case GL_REPLACE:
757            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
758            break;
759         default:
760            _mesa_problem(ctx, "bad tex env mode (8) in SPAN_LINEAR");
761            return;
762         }
763         break;
764      }
765      break;
766   }
767
768   ASSERT(span->arrayMask & SPAN_RGBA);
769   _swrast_write_rgba_span(ctx, span);
770
771#undef SPAN_NEAREST
772#undef SPAN_LINEAR
773
774   /* restore state */
775   ctx->Texture._EnabledUnits = savedTexEnable;
776}
777
778
779/*
780 * Render an perspective corrected RGB/RGBA textured triangle.
781 * The Q (aka V in Mesa) coordinate must be zero such that the divide
782 * by interpolated Q/W comes out right.
783 *
784 */
785#define NAME persp_textured_triangle
786#define INTERP_Z 1
787#define INTERP_W 1
788#define INTERP_FOG 1
789#define INTERP_RGB 1
790#define INTERP_ALPHA 1
791#define INTERP_ATTRIBS 1
792
793#define SETUP_CODE							\
794   struct persp_info info;						\
795   const struct gl_texture_unit *unit = ctx->Texture.Unit+0;		\
796   const struct gl_texture_object *obj = unit->Current2D;		\
797   const GLint b = obj->BaseLevel;					\
798   info.texture = (const GLchan *) obj->Image[0][b]->Data;		\
799   info.twidth_log2 = obj->Image[0][b]->WidthLog2;			\
800   info.smask = obj->Image[0][b]->Width - 1;				\
801   info.tmask = obj->Image[0][b]->Height - 1;				\
802   info.format = obj->Image[0][b]->_BaseFormat;				\
803   info.filter = obj->MinFilter;					\
804   info.envmode = unit->EnvMode;					\
805									\
806   if (info.envmode == GL_BLEND) {					\
807      /* potential off-by-one error here? (1.0f -> 2048 -> 0) */	\
808      info.er = FloatToFixed(unit->EnvColor[RCOMP] * CHAN_MAXF);	\
809      info.eg = FloatToFixed(unit->EnvColor[GCOMP] * CHAN_MAXF);	\
810      info.eb = FloatToFixed(unit->EnvColor[BCOMP] * CHAN_MAXF);	\
811      info.ea = FloatToFixed(unit->EnvColor[ACOMP] * CHAN_MAXF);	\
812   }									\
813   if (!info.texture) {							\
814      /* this shouldn't happen */					\
815      return;								\
816   }									\
817									\
818   switch (info.format) {						\
819   case GL_ALPHA:							\
820   case GL_LUMINANCE:							\
821   case GL_INTENSITY:							\
822      info.tbytesline = obj->Image[0][b]->Width;			\
823      break;								\
824   case GL_LUMINANCE_ALPHA:						\
825      info.tbytesline = obj->Image[0][b]->Width * 2;			\
826      break;								\
827   case GL_RGB:								\
828      info.tbytesline = obj->Image[0][b]->Width * 3;			\
829      break;								\
830   case GL_RGBA:							\
831      info.tbytesline = obj->Image[0][b]->Width * 4;			\
832      break;								\
833   default:								\
834      _mesa_problem(NULL, "Bad texture format in persp_textured_triangle");\
835      return;								\
836   }									\
837   info.tsize = obj->Image[0][b]->Height * info.tbytesline;
838
839#define RENDER_SPAN( span )			\
840   span.interpMask &= ~SPAN_RGBA;		\
841   span.arrayMask |= SPAN_RGBA;			\
842   fast_persp_span(ctx, &span, &info);
843
844#include "s_tritemp.h"
845
846
847#endif /* CHAN_BITS != GL_FLOAT */
848
849
850
851
852/*
853 * Render an RGBA triangle with arbitrary attributes.
854 */
855#define NAME general_triangle
856#define INTERP_Z 1
857#define INTERP_W 1
858#define INTERP_FOG 1
859#define INTERP_RGB 1
860#define INTERP_SPEC 1
861#define INTERP_ALPHA 1
862#define INTERP_ATTRIBS 1
863#define RENDER_SPAN( span )   _swrast_write_rgba_span(ctx, &span);
864#include "s_tritemp.h"
865
866
867
868
869/*
870 * Special tri function for occlusion testing
871 */
872#define NAME occlusion_zless_triangle
873#define INTERP_Z 1
874#define SETUP_CODE							\
875   struct gl_renderbuffer *rb = ctx->DrawBuffer->_DepthBuffer;		\
876   struct gl_query_object *q = ctx->Query.CurrentOcclusionObject;	\
877   ASSERT(ctx->Depth.Test);						\
878   ASSERT(!ctx->Depth.Mask);						\
879   ASSERT(ctx->Depth.Func == GL_LESS);					\
880   if (!q) {								\
881      return;								\
882   }
883#define RENDER_SPAN( span )						\
884   if (rb->DepthBits <= 16) {						\
885      GLuint i;								\
886      const GLushort *zRow = (const GLushort *)				\
887         rb->GetPointer(ctx, rb, span.x, span.y);			\
888      for (i = 0; i < span.end; i++) {					\
889         GLuint z = FixedToDepth(span.z);				\
890         if (z < zRow[i]) {						\
891            q->Result++;						\
892         }								\
893         span.z += span.zStep;						\
894      }									\
895   }									\
896   else {								\
897      GLuint i;								\
898      const GLuint *zRow = (const GLuint *)				\
899         rb->GetPointer(ctx, rb, span.x, span.y);			\
900      for (i = 0; i < span.end; i++) {					\
901         if ((GLuint)span.z < zRow[i]) {				\
902            q->Result++;						\
903         }								\
904         span.z += span.zStep;						\
905      }									\
906   }
907#include "s_tritemp.h"
908
909
910
911static void
912nodraw_triangle( GLcontext *ctx,
913                 const SWvertex *v0,
914                 const SWvertex *v1,
915                 const SWvertex *v2 )
916{
917   (void) (ctx && v0 && v1 && v2);
918}
919
920
921/*
922 * This is used when separate specular color is enabled, but not
923 * texturing.  We add the specular color to the primary color,
924 * draw the triangle, then restore the original primary color.
925 * Inefficient, but seldom needed.
926 */
927void _swrast_add_spec_terms_triangle( GLcontext *ctx,
928				      const SWvertex *v0,
929				      const SWvertex *v1,
930				      const SWvertex *v2 )
931{
932   SWvertex *ncv0 = (SWvertex *)v0; /* drop const qualifier */
933   SWvertex *ncv1 = (SWvertex *)v1;
934   SWvertex *ncv2 = (SWvertex *)v2;
935#if CHAN_TYPE == GL_FLOAT
936   GLfloat rSum, gSum, bSum;
937#else
938   GLint rSum, gSum, bSum;
939#endif
940   GLchan c[3][4];
941   /* save original colors */
942   COPY_CHAN4( c[0], ncv0->color );
943   COPY_CHAN4( c[1], ncv1->color );
944   COPY_CHAN4( c[2], ncv2->color );
945   /* sum v0 */
946   rSum = ncv0->color[0] + ncv0->specular[0];
947   gSum = ncv0->color[1] + ncv0->specular[1];
948   bSum = ncv0->color[2] + ncv0->specular[2];
949   ncv0->color[0] = MIN2(rSum, CHAN_MAX);
950   ncv0->color[1] = MIN2(gSum, CHAN_MAX);
951   ncv0->color[2] = MIN2(bSum, CHAN_MAX);
952   /* sum v1 */
953   rSum = ncv1->color[0] + ncv1->specular[0];
954   gSum = ncv1->color[1] + ncv1->specular[1];
955   bSum = ncv1->color[2] + ncv1->specular[2];
956   ncv1->color[0] = MIN2(rSum, CHAN_MAX);
957   ncv1->color[1] = MIN2(gSum, CHAN_MAX);
958   ncv1->color[2] = MIN2(bSum, CHAN_MAX);
959   /* sum v2 */
960   rSum = ncv2->color[0] + ncv2->specular[0];
961   gSum = ncv2->color[1] + ncv2->specular[1];
962   bSum = ncv2->color[2] + ncv2->specular[2];
963   ncv2->color[0] = MIN2(rSum, CHAN_MAX);
964   ncv2->color[1] = MIN2(gSum, CHAN_MAX);
965   ncv2->color[2] = MIN2(bSum, CHAN_MAX);
966   /* draw */
967   SWRAST_CONTEXT(ctx)->SpecTriangle( ctx, ncv0, ncv1, ncv2 );
968   /* restore original colors */
969   COPY_CHAN4( ncv0->color, c[0] );
970   COPY_CHAN4( ncv1->color, c[1] );
971   COPY_CHAN4( ncv2->color, c[2] );
972}
973
974
975
976#ifdef DEBUG
977
978/* record the current triangle function name */
979const char *_mesa_triFuncName = NULL;
980
981#define USE(triFunc)				\
982do {						\
983    _mesa_triFuncName = #triFunc;		\
984    /*printf("%s\n", _mesa_triFuncName);*/	\
985    swrast->Triangle = triFunc;			\
986} while (0)
987
988#else
989
990#define USE(triFunc)  swrast->Triangle = triFunc;
991
992#endif
993
994
995
996
997/*
998 * Determine which triangle rendering function to use given the current
999 * rendering context.
1000 *
1001 * Please update the summary flag _SWRAST_NEW_TRIANGLE if you add or
1002 * remove tests to this code.
1003 */
1004void
1005_swrast_choose_triangle( GLcontext *ctx )
1006{
1007   SWcontext *swrast = SWRAST_CONTEXT(ctx);
1008   const GLboolean rgbmode = ctx->Visual.rgbMode;
1009
1010   if (ctx->Polygon.CullFlag &&
1011       ctx->Polygon.CullFaceMode == GL_FRONT_AND_BACK) {
1012      USE(nodraw_triangle);
1013      return;
1014   }
1015
1016   if (ctx->RenderMode==GL_RENDER) {
1017
1018      if (ctx->Polygon.SmoothFlag) {
1019         _swrast_set_aa_triangle_function(ctx);
1020         ASSERT(swrast->Triangle);
1021         return;
1022      }
1023
1024      /* special case for occlusion testing */
1025      if (ctx->Query.CurrentOcclusionObject &&
1026          ctx->Depth.Test &&
1027          ctx->Depth.Mask == GL_FALSE &&
1028          ctx->Depth.Func == GL_LESS &&
1029          !ctx->Stencil.Enabled) {
1030         if ((rgbmode &&
1031              ctx->Color.ColorMask[0] == 0 &&
1032              ctx->Color.ColorMask[1] == 0 &&
1033              ctx->Color.ColorMask[2] == 0 &&
1034              ctx->Color.ColorMask[3] == 0)
1035             ||
1036             (!rgbmode && ctx->Color.IndexMask == 0)) {
1037            USE(occlusion_zless_triangle);
1038            return;
1039         }
1040      }
1041
1042      if (!rgbmode) {
1043         USE(ci_triangle);
1044         return;
1045      }
1046
1047      if (ctx->Texture._EnabledCoordUnits ||
1048          ctx->FragmentProgram._Current ||
1049          ctx->ATIFragmentShader._Enabled) {
1050         /* Ugh, we do a _lot_ of tests to pick the best textured tri func */
1051         const struct gl_texture_object *texObj2D;
1052         const struct gl_texture_image *texImg;
1053         GLenum minFilter, magFilter, envMode;
1054         GLint format;
1055         texObj2D = ctx->Texture.Unit[0].Current2D;
1056         texImg = texObj2D ? texObj2D->Image[0][texObj2D->BaseLevel] : NULL;
1057         format = texImg ? texImg->TexFormat->MesaFormat : -1;
1058         minFilter = texObj2D ? texObj2D->MinFilter : (GLenum) 0;
1059         magFilter = texObj2D ? texObj2D->MagFilter : (GLenum) 0;
1060         envMode = ctx->Texture.Unit[0].EnvMode;
1061
1062         /* First see if we can use an optimized 2-D texture function */
1063         if (ctx->Texture._EnabledCoordUnits == 0x1
1064             && !ctx->FragmentProgram._Current
1065             && !ctx->ATIFragmentShader._Enabled
1066             && ctx->Texture.Unit[0]._ReallyEnabled == TEXTURE_2D_BIT
1067             && texObj2D->WrapS == GL_REPEAT
1068             && texObj2D->WrapT == GL_REPEAT
1069             && texImg->_IsPowerOfTwo
1070             && texImg->Border == 0
1071             && texImg->Width == texImg->RowStride
1072             && (format == MESA_FORMAT_RGB || format == MESA_FORMAT_RGBA)
1073             && minFilter == magFilter
1074             && ctx->Light.Model.ColorControl == GL_SINGLE_COLOR
1075             && ctx->Texture.Unit[0].EnvMode != GL_COMBINE_EXT) {
1076	    if (ctx->Hint.PerspectiveCorrection==GL_FASTEST) {
1077	       if (minFilter == GL_NEAREST
1078		   && format == MESA_FORMAT_RGB
1079		   && (envMode == GL_REPLACE || envMode == GL_DECAL)
1080		   && ((swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)
1081			&& ctx->Depth.Func == GL_LESS
1082			&& ctx->Depth.Mask == GL_TRUE)
1083		       || swrast->_RasterMask == TEXTURE_BIT)
1084		   && ctx->Polygon.StippleFlag == GL_FALSE
1085                   && ctx->DrawBuffer->Visual.depthBits <= 16) {
1086		  if (swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)) {
1087		     USE(simple_z_textured_triangle);
1088		  }
1089		  else {
1090		     USE(simple_textured_triangle);
1091		  }
1092	       }
1093	       else {
1094#if (CHAN_BITS == 16 || CHAN_BITS == 32)
1095                  USE(general_triangle);
1096#else
1097                  USE(affine_textured_triangle);
1098#endif
1099	       }
1100	    }
1101	    else {
1102#if (CHAN_BITS == 16 || CHAN_BITS == 32)
1103               USE(general_triangle);
1104#else
1105               USE(persp_textured_triangle);
1106#endif
1107	    }
1108	 }
1109         else {
1110            /* general case textured triangles */
1111            USE(general_triangle);
1112         }
1113      }
1114      else {
1115         ASSERT(!ctx->Texture._EnabledCoordUnits);
1116	 if (ctx->Light.ShadeModel==GL_SMOOTH) {
1117	    /* smooth shaded, no texturing, stippled or some raster ops */
1118            USE(smooth_rgba_triangle);
1119	 }
1120	 else {
1121	    /* flat shaded, no texturing, stippled or some raster ops */
1122            USE(flat_rgba_triangle);
1123	 }
1124      }
1125   }
1126   else if (ctx->RenderMode==GL_FEEDBACK) {
1127      USE(_swrast_feedback_triangle);
1128   }
1129   else {
1130      /* GL_SELECT mode */
1131      USE(_swrast_select_triangle);
1132   }
1133}
1134