s_triangle.c revision a9fc8ba756dd25a07dc19058fe60f65bda82a055
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.5
4 *
5 * Copyright (C) 1999-2005  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_depth.h"
42#include "s_feedback.h"
43#include "s_span.h"
44#include "s_triangle.h"
45
46
47/*
48 * Just used for feedback mode.
49 */
50GLboolean
51_swrast_culltriangle( GLcontext *ctx,
52                      const SWvertex *v0,
53                      const SWvertex *v1,
54                      const SWvertex *v2 )
55{
56   GLfloat ex = v1->win[0] - v0->win[0];
57   GLfloat ey = v1->win[1] - v0->win[1];
58   GLfloat fx = v2->win[0] - v0->win[0];
59   GLfloat fy = v2->win[1] - v0->win[1];
60   GLfloat c = ex*fy-ey*fx;
61
62   if (c * SWRAST_CONTEXT(ctx)->_BackfaceSign > 0)
63      return 0;
64
65   return 1;
66}
67
68
69
70/*
71 * Render a flat-shaded color index triangle.
72 */
73#define NAME flat_ci_triangle
74#define INTERP_Z 1
75#define INTERP_FOG 1
76#define SETUP_CODE			\
77   span.interpMask |= SPAN_INDEX;	\
78   span.index = FloatToFixed(v2->index);\
79   span.indexStep = 0;
80#define RENDER_SPAN( span )  _swrast_write_index_span(ctx, &span);
81#include "s_tritemp.h"
82
83
84
85/*
86 * Render a smooth-shaded color index triangle.
87 */
88#define NAME smooth_ci_triangle
89#define INTERP_Z 1
90#define INTERP_FOG 1
91#define INTERP_INDEX 1
92#define RENDER_SPAN( span )  _swrast_write_index_span(ctx, &span);
93#include "s_tritemp.h"
94
95
96
97/*
98 * Render a flat-shaded RGBA triangle.
99 */
100#define NAME flat_rgba_triangle
101#define INTERP_Z 1
102#define INTERP_FOG 1
103#define SETUP_CODE				\
104   ASSERT(ctx->Texture._EnabledCoordUnits == 0);\
105   ASSERT(ctx->Light.ShadeModel==GL_FLAT);	\
106   span.interpMask |= SPAN_RGBA;		\
107   span.red = ChanToFixed(v2->color[0]);	\
108   span.green = ChanToFixed(v2->color[1]);	\
109   span.blue = ChanToFixed(v2->color[2]);	\
110   span.alpha = ChanToFixed(v2->color[3]);	\
111   span.redStep = 0;				\
112   span.greenStep = 0;				\
113   span.blueStep = 0;				\
114   span.alphaStep = 0;
115#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
116#include "s_tritemp.h"
117
118
119
120/*
121 * Render a smooth-shaded RGBA triangle.
122 */
123#define NAME smooth_rgba_triangle
124#define INTERP_Z 1
125#define INTERP_FOG 1
126#define INTERP_RGB 1
127#define INTERP_ALPHA 1
128#define SETUP_CODE				\
129   {						\
130      /* texturing must be off */		\
131      ASSERT(ctx->Texture._EnabledCoordUnits == 0);	\
132      ASSERT(ctx->Light.ShadeModel==GL_SMOOTH);	\
133   }
134#define RENDER_SPAN( span )  _swrast_write_rgba_span(ctx, &span);
135#include "s_tritemp.h"
136
137
138
139/*
140 * Render an RGB, GL_DECAL, textured triangle.
141 * Interpolate S,T only w/out mipmapping or perspective correction.
142 *
143 * No fog.
144 */
145#define NAME simple_textured_triangle
146#define INTERP_INT_TEX 1
147#define S_SCALE twidth
148#define T_SCALE theight
149
150#define SETUP_CODE							\
151   struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0][0];\
152   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
153   const GLint b = obj->BaseLevel;					\
154   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
155   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
156   const GLint twidth_log2 = obj->Image[0][b]->WidthLog2;		\
157   const GLchan *texture = (const GLchan *) obj->Image[0][b]->Data;	\
158   const GLint smask = obj->Image[0][b]->Width - 1;			\
159   const GLint tmask = obj->Image[0][b]->Height - 1;			\
160   if (!texture) {							\
161      /* this shouldn't happen */					\
162      return;								\
163   }
164
165#define RENDER_SPAN( span  )						\
166   GLuint i;								\
167   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
168   span.intTex[1] -= FIXED_HALF;					\
169   for (i = 0; i < span.end; i++) {					\
170      GLint s = FixedToInt(span.intTex[0]) & smask;			\
171      GLint t = FixedToInt(span.intTex[1]) & tmask;			\
172      GLint pos = (t << twidth_log2) + s;				\
173      pos = pos + pos + pos;  /* multiply by 3 */			\
174      span.array->rgb[i][RCOMP] = texture[pos];				\
175      span.array->rgb[i][GCOMP] = texture[pos+1];			\
176      span.array->rgb[i][BCOMP] = texture[pos+2];			\
177      span.intTex[0] += span.intTexStep[0];				\
178      span.intTex[1] += span.intTexStep[1];				\
179   }									\
180   rb->PutRowRGB(ctx, rb, span.end, span.x, span.y, span.array->rgb, NULL);
181
182#include "s_tritemp.h"
183
184
185
186/*
187 * Render an RGB, GL_DECAL, textured triangle.
188 * Interpolate S,T, GL_LESS depth test, w/out mipmapping or
189 * perspective correction.
190 * Depth buffer bits must be <= sizeof(DEFAULT_SOFTWARE_DEPTH_TYPE)
191 *
192 * No fog.
193 */
194#define NAME simple_z_textured_triangle
195#define INTERP_Z 1
196#define DEPTH_TYPE DEFAULT_SOFTWARE_DEPTH_TYPE
197#define INTERP_INT_TEX 1
198#define S_SCALE twidth
199#define T_SCALE theight
200
201#define SETUP_CODE							\
202   struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0][0];\
203   struct gl_texture_object *obj = ctx->Texture.Unit[0].Current2D;	\
204   const GLint b = obj->BaseLevel;					\
205   const GLfloat twidth = (GLfloat) obj->Image[0][b]->Width;		\
206   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
207   const GLint twidth_log2 = obj->Image[0][b]->WidthLog2;		\
208   const GLchan *texture = (const GLchan *) obj->Image[0][b]->Data;	\
209   const GLint smask = obj->Image[0][b]->Width - 1;			\
210   const GLint tmask = obj->Image[0][b]->Height - 1;			\
211   if (!texture) {							\
212      /* this shouldn't happen */					\
213      return;								\
214   }
215
216#define RENDER_SPAN( span )						\
217   GLuint i;				    				\
218   span.intTex[0] -= FIXED_HALF; /* off-by-one error? */		\
219   span.intTex[1] -= FIXED_HALF;					\
220   for (i = 0; i < span.end; i++) {					\
221      const GLuint z = FixedToDepth(span.z);				\
222      if (z < zRow[i]) {						\
223         GLint s = FixedToInt(span.intTex[0]) & smask;			\
224         GLint t = FixedToInt(span.intTex[1]) & tmask;			\
225         GLint pos = (t << twidth_log2) + s;				\
226         pos = pos + pos + pos;  /* multiply by 3 */			\
227         span.array->rgb[i][RCOMP] = texture[pos];			\
228         span.array->rgb[i][GCOMP] = texture[pos+1];			\
229         span.array->rgb[i][BCOMP] = texture[pos+2];			\
230         zRow[i] = z;							\
231         span.array->mask[i] = 1;					\
232      }									\
233      else {								\
234         span.array->mask[i] = 0;					\
235      }									\
236      span.intTex[0] += span.intTexStep[0];				\
237      span.intTex[1] += span.intTexStep[1];				\
238      span.z += span.zStep;						\
239   }									\
240   rb->PutRowRGB(ctx, rb, span.end, span.x, span.y,			\
241                 span.array->rgb, span.array->mask);
242
243#include "s_tritemp.h"
244
245
246
247#if CHAN_TYPE != GL_FLOAT
248
249struct affine_info
250{
251   GLenum filter;
252   GLenum format;
253   GLenum envmode;
254   GLint smask, tmask;
255   GLint twidth_log2;
256   const GLchan *texture;
257   GLfixed er, eg, eb, ea;
258   GLint tbytesline, tsize;
259};
260
261
262static INLINE GLint
263ilerp(GLint t, GLint a, GLint b)
264{
265   return a + ((t * (b - a)) >> FIXED_SHIFT);
266}
267
268static INLINE GLint
269ilerp_2d(GLint ia, GLint ib, GLint v00, GLint v10, GLint v01, GLint v11)
270{
271   const GLint temp0 = ilerp(ia, v00, v10);
272   const GLint temp1 = ilerp(ia, v01, v11);
273   return ilerp(ib, temp0, temp1);
274}
275
276
277/* This function can handle GL_NEAREST or GL_LINEAR sampling of 2D RGB or RGBA
278 * textures with GL_REPLACE, GL_MODULATE, GL_BLEND, GL_DECAL or GL_ADD
279 * texture env modes.
280 */
281static INLINE void
282affine_span(GLcontext *ctx, struct sw_span *span,
283            struct affine_info *info)
284{
285   GLchan sample[4];  /* the filtered texture sample */
286
287   /* Instead of defining a function for each mode, a test is done
288    * between the outer and inner loops. This is to reduce code size
289    * and complexity. Observe that an optimizing compiler kills
290    * unused variables (for instance tf,sf,ti,si in case of GL_NEAREST).
291    */
292
293#define NEAREST_RGB			\
294   sample[RCOMP] = tex00[RCOMP];	\
295   sample[GCOMP] = tex00[GCOMP];	\
296   sample[BCOMP] = tex00[BCOMP];	\
297   sample[ACOMP] = CHAN_MAX
298
299#define LINEAR_RGB							\
300   sample[RCOMP] = ilerp_2d(sf, tf, tex00[0], tex01[0], tex10[0], tex11[0]);\
301   sample[GCOMP] = ilerp_2d(sf, tf, tex00[1], tex01[1], tex10[1], tex11[1]);\
302   sample[BCOMP] = ilerp_2d(sf, tf, tex00[2], tex01[2], tex10[2], tex11[2]);\
303   sample[ACOMP] = CHAN_MAX;
304
305#define NEAREST_RGBA  COPY_CHAN4(sample, tex00)
306
307#define LINEAR_RGBA							\
308   sample[RCOMP] = ilerp_2d(sf, tf, tex00[0], tex01[0], tex10[0], tex11[0]);\
309   sample[GCOMP] = ilerp_2d(sf, tf, tex00[1], tex01[1], tex10[1], tex11[1]);\
310   sample[BCOMP] = ilerp_2d(sf, tf, tex00[2], tex01[2], tex10[2], tex11[2]);\
311   sample[ACOMP] = ilerp_2d(sf, tf, tex00[3], tex01[3], tex10[3], tex11[3])
312
313#define MODULATE							  \
314   dest[RCOMP] = span->red   * (sample[RCOMP] + 1u) >> (FIXED_SHIFT + 8); \
315   dest[GCOMP] = span->green * (sample[GCOMP] + 1u) >> (FIXED_SHIFT + 8); \
316   dest[BCOMP] = span->blue  * (sample[BCOMP] + 1u) >> (FIXED_SHIFT + 8); \
317   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1u) >> (FIXED_SHIFT + 8)
318
319#define DECAL								\
320   dest[RCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->red +		\
321               ((sample[ACOMP] + 1) * sample[RCOMP] << FIXED_SHIFT))	\
322               >> (FIXED_SHIFT + 8);					\
323   dest[GCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->green +		\
324               ((sample[ACOMP] + 1) * sample[GCOMP] << FIXED_SHIFT))	\
325               >> (FIXED_SHIFT + 8);					\
326   dest[BCOMP] = ((CHAN_MAX - sample[ACOMP]) * span->blue +		\
327               ((sample[ACOMP] + 1) * sample[BCOMP] << FIXED_SHIFT))	\
328               >> (FIXED_SHIFT + 8);					\
329   dest[ACOMP] = FixedToInt(span->alpha)
330
331#define BLEND								\
332   dest[RCOMP] = ((CHAN_MAX - sample[RCOMP]) * span->red		\
333               + (sample[RCOMP] + 1) * info->er) >> (FIXED_SHIFT + 8);	\
334   dest[GCOMP] = ((CHAN_MAX - sample[GCOMP]) * span->green		\
335               + (sample[GCOMP] + 1) * info->eg) >> (FIXED_SHIFT + 8);	\
336   dest[BCOMP] = ((CHAN_MAX - sample[BCOMP]) * span->blue		\
337               + (sample[BCOMP] + 1) * info->eb) >> (FIXED_SHIFT + 8);	\
338   dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8)
339
340#define REPLACE  COPY_CHAN4(dest, sample)
341
342#define ADD								\
343   {									\
344      GLint rSum = FixedToInt(span->red)   + (GLint) sample[RCOMP];	\
345      GLint gSum = FixedToInt(span->green) + (GLint) sample[GCOMP];	\
346      GLint bSum = FixedToInt(span->blue)  + (GLint) sample[BCOMP];	\
347      dest[RCOMP] = MIN2(rSum, CHAN_MAX);				\
348      dest[GCOMP] = MIN2(gSum, CHAN_MAX);				\
349      dest[BCOMP] = MIN2(bSum, CHAN_MAX);				\
350      dest[ACOMP] = span->alpha * (sample[ACOMP] + 1) >> (FIXED_SHIFT + 8); \
351  }
352
353/* shortcuts */
354
355#define NEAREST_RGB_REPLACE		\
356   NEAREST_RGB;				\
357   dest[0] = sample[0];			\
358   dest[1] = sample[1];			\
359   dest[2] = sample[2];			\
360   dest[3] = FixedToInt(span->alpha);
361
362#define NEAREST_RGBA_REPLACE  COPY_CHAN4(dest, tex00)
363
364#define SPAN_NEAREST(DO_TEX, COMPS)					\
365	for (i = 0; i < span->end; i++) {				\
366           /* Isn't it necessary to use FixedFloor below?? */		\
367           GLint s = FixedToInt(span->intTex[0]) & info->smask;		\
368           GLint t = FixedToInt(span->intTex[1]) & info->tmask;		\
369           GLint pos = (t << info->twidth_log2) + s;			\
370           const GLchan *tex00 = info->texture + COMPS * pos;		\
371           DO_TEX;							\
372           span->red += span->redStep;					\
373	   span->green += span->greenStep;				\
374           span->blue += span->blueStep;				\
375	   span->alpha += span->alphaStep;				\
376	   span->intTex[0] += span->intTexStep[0];			\
377	   span->intTex[1] += span->intTexStep[1];			\
378           dest += 4;							\
379	}
380
381#define SPAN_LINEAR(DO_TEX, COMPS)					\
382	for (i = 0; i < span->end; i++) {				\
383           /* Isn't it necessary to use FixedFloor below?? */		\
384           const GLint s = FixedToInt(span->intTex[0]) & info->smask;	\
385           const GLint t = FixedToInt(span->intTex[1]) & info->tmask;	\
386           const GLfixed sf = span->intTex[0] & FIXED_FRAC_MASK;	\
387           const GLfixed tf = span->intTex[1] & FIXED_FRAC_MASK;	\
388           const GLint pos = (t << info->twidth_log2) + s;		\
389           const GLchan *tex00 = info->texture + COMPS * pos;		\
390           const GLchan *tex10 = tex00 + info->tbytesline;		\
391           const GLchan *tex01 = tex00 + COMPS;				\
392           const GLchan *tex11 = tex10 + COMPS;				\
393           if (t == info->tmask) {					\
394              tex10 -= info->tsize;					\
395              tex11 -= info->tsize;					\
396           }								\
397           if (s == info->smask) {					\
398              tex01 -= info->tbytesline;				\
399              tex11 -= info->tbytesline;				\
400           }								\
401           DO_TEX;							\
402           span->red += span->redStep;					\
403	   span->green += span->greenStep;				\
404           span->blue += span->blueStep;				\
405	   span->alpha += span->alphaStep;				\
406	   span->intTex[0] += span->intTexStep[0];			\
407	   span->intTex[1] += span->intTexStep[1];			\
408           dest += 4;							\
409	}
410
411
412   GLuint i;
413   GLchan *dest = span->array->rgba[0];
414
415   span->intTex[0] -= FIXED_HALF;
416   span->intTex[1] -= FIXED_HALF;
417   switch (info->filter) {
418   case GL_NEAREST:
419      switch (info->format) {
420      case GL_RGB:
421         switch (info->envmode) {
422         case GL_MODULATE:
423            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
424            break;
425         case GL_DECAL:
426         case GL_REPLACE:
427            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
428            break;
429         case GL_BLEND:
430            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
431            break;
432         case GL_ADD:
433            SPAN_NEAREST(NEAREST_RGB;ADD,3);
434            break;
435         default:
436            _mesa_problem(ctx, "bad tex env mode in SPAN_LINEAR");
437            return;
438         }
439         break;
440      case GL_RGBA:
441         switch(info->envmode) {
442         case GL_MODULATE:
443            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
444            break;
445         case GL_DECAL:
446            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
447            break;
448         case GL_BLEND:
449            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
450            break;
451         case GL_ADD:
452            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
453            break;
454         case GL_REPLACE:
455            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
456            break;
457         default:
458            _mesa_problem(ctx, "bad tex env mode (2) in SPAN_LINEAR");
459            return;
460         }
461         break;
462      }
463      break;
464
465   case GL_LINEAR:
466      span->intTex[0] -= FIXED_HALF;
467      span->intTex[1] -= FIXED_HALF;
468      switch (info->format) {
469      case GL_RGB:
470         switch (info->envmode) {
471         case GL_MODULATE:
472            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
473            break;
474         case GL_DECAL:
475         case GL_REPLACE:
476            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
477            break;
478         case GL_BLEND:
479            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
480            break;
481         case GL_ADD:
482            SPAN_LINEAR(LINEAR_RGB;ADD,3);
483            break;
484         default:
485            _mesa_problem(ctx, "bad tex env mode (3) in SPAN_LINEAR");
486            return;
487         }
488         break;
489      case GL_RGBA:
490         switch (info->envmode) {
491         case GL_MODULATE:
492            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
493            break;
494         case GL_DECAL:
495            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
496            break;
497         case GL_BLEND:
498            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
499            break;
500         case GL_ADD:
501            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
502            break;
503         case GL_REPLACE:
504            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
505            break;
506         default:
507            _mesa_problem(ctx, "bad tex env mode (4) in SPAN_LINEAR");
508            return;
509         }
510         break;
511      }
512      break;
513   }
514   span->interpMask &= ~SPAN_RGBA;
515   ASSERT(span->arrayMask & SPAN_RGBA);
516   _swrast_write_rgba_span(ctx, span);
517
518#undef SPAN_NEAREST
519#undef SPAN_LINEAR
520}
521
522
523
524/*
525 * Render an RGB/RGBA textured triangle without perspective correction.
526 */
527#define NAME affine_textured_triangle
528#define INTERP_Z 1
529#define INTERP_FOG 1
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[0][b]->Width;		\
542   const GLfloat theight = (GLfloat) obj->Image[0][b]->Height;		\
543   info.texture = (const GLchan *) obj->Image[0][b]->Data;		\
544   info.twidth_log2 = obj->Image[0][b]->WidthLog2;			\
545   info.smask = obj->Image[0][b]->Width - 1;				\
546   info.tmask = obj->Image[0][b]->Height - 1;				\
547   info.format = obj->Image[0][b]->_BaseFormat;				\
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[0][b]->Width;			\
569      break;								\
570   case GL_LUMINANCE_ALPHA:						\
571      info.tbytesline = obj->Image[0][b]->Width * 2;			\
572      break;								\
573   case GL_RGB:								\
574      info.tbytesline = obj->Image[0][b]->Width * 3;			\
575      break;								\
576   case GL_RGBA:							\
577      info.tbytesline = obj->Image[0][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[0][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           const GLfloat s_tmp = (GLfloat) (tex_coord[0] * invQ);	\
641           const GLfloat t_tmp = (GLfloat) (tex_coord[1] * invQ);	\
642           const GLfixed s_fix = FloatToFixed(s_tmp) - FIXED_HALF;	\
643           const GLfixed t_fix = FloatToFixed(t_tmp) - FIXED_HALF;      \
644           const GLint s = FixedToInt(FixedFloor(s_fix)) & info->smask;	\
645           const GLint t = FixedToInt(FixedFloor(t_fix)) & info->tmask;	\
646           const GLfixed sf = s_fix & FIXED_FRAC_MASK;			\
647           const GLfixed tf = t_fix & FIXED_FRAC_MASK;			\
648           const GLint pos = (t << info->twidth_log2) + s;		\
649           const GLchan *tex00 = info->texture + COMP * pos;		\
650           const GLchan *tex10 = tex00 + info->tbytesline;		\
651           const GLchan *tex01 = tex00 + COMP;				\
652           const GLchan *tex11 = tex10 + COMP;				\
653           if (t == info->tmask) {					\
654              tex10 -= info->tsize;					\
655              tex11 -= info->tsize;					\
656           }								\
657           if (s == info->smask) {					\
658              tex01 -= info->tbytesline;				\
659              tex11 -= info->tbytesline;				\
660           }								\
661           DO_TEX;							\
662           span->red   += span->redStep;				\
663	   span->green += span->greenStep;				\
664           span->blue  += span->blueStep;				\
665	   span->alpha += span->alphaStep;				\
666	   tex_coord[0] += tex_step[0];					\
667	   tex_coord[1] += tex_step[1];					\
668	   tex_coord[2] += tex_step[2];					\
669           dest += 4;							\
670	}
671
672   GLuint i;
673   GLfloat tex_coord[3], tex_step[3];
674   GLchan *dest = span->array->rgba[0];
675
676   const GLuint savedTexEnable = ctx->Texture._EnabledUnits;
677   ctx->Texture._EnabledUnits = 0;
678
679   tex_coord[0] = span->tex[0][0]  * (info->smask + 1);
680   tex_step[0] = span->texStepX[0][0] * (info->smask + 1);
681   tex_coord[1] = span->tex[0][1] * (info->tmask + 1);
682   tex_step[1] = span->texStepX[0][1] * (info->tmask + 1);
683   /* span->tex[0][2] only if 3D-texturing, here only 2D */
684   tex_coord[2] = span->tex[0][3];
685   tex_step[2] = span->texStepX[0][3];
686
687   switch (info->filter) {
688   case GL_NEAREST:
689      switch (info->format) {
690      case GL_RGB:
691         switch (info->envmode) {
692         case GL_MODULATE:
693            SPAN_NEAREST(NEAREST_RGB;MODULATE,3);
694            break;
695         case GL_DECAL:
696         case GL_REPLACE:
697            SPAN_NEAREST(NEAREST_RGB_REPLACE,3);
698            break;
699         case GL_BLEND:
700            SPAN_NEAREST(NEAREST_RGB;BLEND,3);
701            break;
702         case GL_ADD:
703            SPAN_NEAREST(NEAREST_RGB;ADD,3);
704            break;
705         default:
706            _mesa_problem(ctx, "bad tex env mode (5) in SPAN_LINEAR");
707            return;
708         }
709         break;
710      case GL_RGBA:
711         switch(info->envmode) {
712         case GL_MODULATE:
713            SPAN_NEAREST(NEAREST_RGBA;MODULATE,4);
714            break;
715         case GL_DECAL:
716            SPAN_NEAREST(NEAREST_RGBA;DECAL,4);
717            break;
718         case GL_BLEND:
719            SPAN_NEAREST(NEAREST_RGBA;BLEND,4);
720            break;
721         case GL_ADD:
722            SPAN_NEAREST(NEAREST_RGBA;ADD,4);
723            break;
724         case GL_REPLACE:
725            SPAN_NEAREST(NEAREST_RGBA_REPLACE,4);
726            break;
727         default:
728            _mesa_problem(ctx, "bad tex env mode (6) in SPAN_LINEAR");
729            return;
730         }
731         break;
732      }
733      break;
734
735   case GL_LINEAR:
736      switch (info->format) {
737      case GL_RGB:
738         switch (info->envmode) {
739         case GL_MODULATE:
740            SPAN_LINEAR(LINEAR_RGB;MODULATE,3);
741            break;
742         case GL_DECAL:
743         case GL_REPLACE:
744            SPAN_LINEAR(LINEAR_RGB;REPLACE,3);
745            break;
746         case GL_BLEND:
747            SPAN_LINEAR(LINEAR_RGB;BLEND,3);
748            break;
749         case GL_ADD:
750            SPAN_LINEAR(LINEAR_RGB;ADD,3);
751            break;
752         default:
753            _mesa_problem(ctx, "bad tex env mode (7) in SPAN_LINEAR");
754            return;
755         }
756         break;
757      case GL_RGBA:
758         switch (info->envmode) {
759         case GL_MODULATE:
760            SPAN_LINEAR(LINEAR_RGBA;MODULATE,4);
761            break;
762         case GL_DECAL:
763            SPAN_LINEAR(LINEAR_RGBA;DECAL,4);
764            break;
765         case GL_BLEND:
766            SPAN_LINEAR(LINEAR_RGBA;BLEND,4);
767            break;
768         case GL_ADD:
769            SPAN_LINEAR(LINEAR_RGBA;ADD,4);
770            break;
771         case GL_REPLACE:
772            SPAN_LINEAR(LINEAR_RGBA;REPLACE,4);
773            break;
774         default:
775            _mesa_problem(ctx, "bad tex env mode (8) in SPAN_LINEAR");
776            return;
777         }
778         break;
779      }
780      break;
781   }
782
783   ASSERT(span->arrayMask & SPAN_RGBA);
784   _swrast_write_rgba_span(ctx, span);
785
786#undef SPAN_NEAREST
787#undef SPAN_LINEAR
788
789   /* restore state */
790   ctx->Texture._EnabledUnits = savedTexEnable;
791}
792
793
794/*
795 * Render an perspective corrected RGB/RGBA textured triangle.
796 * The Q (aka V in Mesa) coordinate must be zero such that the divide
797 * by interpolated Q/W comes out right.
798 *
799 */
800#define NAME persp_textured_triangle
801#define INTERP_Z 1
802#define INTERP_W 1
803#define INTERP_FOG 1
804#define INTERP_RGB 1
805#define INTERP_ALPHA 1
806#define INTERP_TEX 1
807
808#define SETUP_CODE							\
809   struct persp_info info;						\
810   const struct gl_texture_unit *unit = ctx->Texture.Unit+0;		\
811   const struct gl_texture_object *obj = unit->Current2D;		\
812   const GLint b = obj->BaseLevel;					\
813   info.texture = (const GLchan *) obj->Image[0][b]->Data;		\
814   info.twidth_log2 = obj->Image[0][b]->WidthLog2;			\
815   info.smask = obj->Image[0][b]->Width - 1;				\
816   info.tmask = obj->Image[0][b]->Height - 1;				\
817   info.format = obj->Image[0][b]->_BaseFormat;				\
818   info.filter = obj->MinFilter;					\
819   info.envmode = unit->EnvMode;					\
820									\
821   if (info.envmode == GL_BLEND) {					\
822      /* potential off-by-one error here? (1.0f -> 2048 -> 0) */	\
823      info.er = FloatToFixed(unit->EnvColor[RCOMP] * CHAN_MAXF);	\
824      info.eg = FloatToFixed(unit->EnvColor[GCOMP] * CHAN_MAXF);	\
825      info.eb = FloatToFixed(unit->EnvColor[BCOMP] * CHAN_MAXF);	\
826      info.ea = FloatToFixed(unit->EnvColor[ACOMP] * CHAN_MAXF);	\
827   }									\
828   if (!info.texture) {							\
829      /* this shouldn't happen */					\
830      return;								\
831   }									\
832									\
833   switch (info.format) {						\
834   case GL_ALPHA:							\
835   case GL_LUMINANCE:							\
836   case GL_INTENSITY:							\
837      info.tbytesline = obj->Image[0][b]->Width;			\
838      break;								\
839   case GL_LUMINANCE_ALPHA:						\
840      info.tbytesline = obj->Image[0][b]->Width * 2;			\
841      break;								\
842   case GL_RGB:								\
843      info.tbytesline = obj->Image[0][b]->Width * 3;			\
844      break;								\
845   case GL_RGBA:							\
846      info.tbytesline = obj->Image[0][b]->Width * 4;			\
847      break;								\
848   default:								\
849      _mesa_problem(NULL, "Bad texture format in persp_textured_triangle");\
850      return;								\
851   }									\
852   info.tsize = obj->Image[0][b]->Height * info.tbytesline;
853
854#define RENDER_SPAN( span )			\
855   span.interpMask &= ~SPAN_RGBA;		\
856   span.arrayMask |= SPAN_RGBA;			\
857   fast_persp_span(ctx, &span, &info);
858
859#include "s_tritemp.h"
860
861
862#endif /* CHAN_BITS != GL_FLOAT */
863
864
865
866
867/*
868 * Render a smooth-shaded, textured, RGBA triangle.
869 * Interpolate S,T,R with perspective correction, w/out mipmapping.
870 */
871#define NAME general_textured_triangle
872#define INTERP_Z 1
873#define INTERP_W 1
874#define INTERP_FOG 1
875#define INTERP_RGB 1
876#define INTERP_SPEC 1
877#define INTERP_ALPHA 1
878#define INTERP_TEX 1
879#define RENDER_SPAN( span )   _swrast_write_rgba_span(ctx, &span);
880#include "s_tritemp.h"
881
882
883
884/*
885 * This is the big one!
886 * Interpolate Z, RGB, Alpha, specular, fog, and N sets of texture coordinates.
887 * Yup, it's slow.
888 */
889#define NAME multitextured_triangle
890#define INTERP_Z 1
891#define INTERP_W 1
892#define INTERP_FOG 1
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_rgba_span(ctx, &span);
898#include "s_tritemp.h"
899
900
901
902/*
903 * Special tri function for occlusion testing
904 */
905#define NAME occlusion_zless_triangle
906#define INTERP_Z 1
907#define SETUP_CODE							\
908   struct gl_renderbuffer *rb						\
909      = ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;		\
910   struct gl_query_object *q = ctx->Query.CurrentOcclusionObject;	\
911   ASSERT(ctx->Depth.Test);						\
912   ASSERT(!ctx->Depth.Mask);						\
913   ASSERT(ctx->Depth.Func == GL_LESS);					\
914   if (!q) {								\
915      return;								\
916   }
917#define RENDER_SPAN( span )						\
918   if (ctx->Visual.depthBits <= 16) {					\
919      GLuint i;								\
920      const GLushort *zRow = (const GLushort *)				\
921         rb->GetPointer(ctx, rb, span.x, span.y);			\
922      for (i = 0; i < span.end; i++) {					\
923         GLuint z = FixedToDepth(span.z);				\
924         if (z < zRow[i]) {						\
925            q->Result++;						\
926         }								\
927         span.z += span.zStep;						\
928      }									\
929   }									\
930   else {								\
931      GLuint i;								\
932      const GLuint *zRow = (const GLuint *)				\
933         rb->GetPointer(ctx, rb, span.x, span.y);			\
934      for (i = 0; i < span.end; i++) {					\
935         if ((GLuint)span.z < zRow[i]) {				\
936            q->Result++;						\
937         }								\
938         span.z += span.zStep;						\
939      }									\
940   }
941#include "s_tritemp.h"
942
943
944
945static void
946nodraw_triangle( GLcontext *ctx,
947                 const SWvertex *v0,
948                 const SWvertex *v1,
949                 const SWvertex *v2 )
950{
951   (void) (ctx && v0 && v1 && v2);
952}
953
954
955/*
956 * This is used when separate specular color is enabled, but not
957 * texturing.  We add the specular color to the primary color,
958 * draw the triangle, then restore the original primary color.
959 * Inefficient, but seldom needed.
960 */
961void _swrast_add_spec_terms_triangle( GLcontext *ctx,
962				      const SWvertex *v0,
963				      const SWvertex *v1,
964				      const SWvertex *v2 )
965{
966   SWvertex *ncv0 = (SWvertex *)v0; /* drop const qualifier */
967   SWvertex *ncv1 = (SWvertex *)v1;
968   SWvertex *ncv2 = (SWvertex *)v2;
969#if CHAN_TYPE == GL_FLOAT
970   GLfloat rSum, gSum, bSum;
971#else
972   GLint rSum, gSum, bSum;
973#endif
974   GLchan c[3][4];
975   /* save original colors */
976   COPY_CHAN4( c[0], ncv0->color );
977   COPY_CHAN4( c[1], ncv1->color );
978   COPY_CHAN4( c[2], ncv2->color );
979   /* sum v0 */
980   rSum = ncv0->color[0] + ncv0->specular[0];
981   gSum = ncv0->color[1] + ncv0->specular[1];
982   bSum = ncv0->color[2] + ncv0->specular[2];
983   ncv0->color[0] = MIN2(rSum, CHAN_MAX);
984   ncv0->color[1] = MIN2(gSum, CHAN_MAX);
985   ncv0->color[2] = MIN2(bSum, CHAN_MAX);
986   /* sum v1 */
987   rSum = ncv1->color[0] + ncv1->specular[0];
988   gSum = ncv1->color[1] + ncv1->specular[1];
989   bSum = ncv1->color[2] + ncv1->specular[2];
990   ncv1->color[0] = MIN2(rSum, CHAN_MAX);
991   ncv1->color[1] = MIN2(gSum, CHAN_MAX);
992   ncv1->color[2] = MIN2(bSum, CHAN_MAX);
993   /* sum v2 */
994   rSum = ncv2->color[0] + ncv2->specular[0];
995   gSum = ncv2->color[1] + ncv2->specular[1];
996   bSum = ncv2->color[2] + ncv2->specular[2];
997   ncv2->color[0] = MIN2(rSum, CHAN_MAX);
998   ncv2->color[1] = MIN2(gSum, CHAN_MAX);
999   ncv2->color[2] = MIN2(bSum, CHAN_MAX);
1000   /* draw */
1001   SWRAST_CONTEXT(ctx)->SpecTriangle( ctx, ncv0, ncv1, ncv2 );
1002   /* restore original colors */
1003   COPY_CHAN4( ncv0->color, c[0] );
1004   COPY_CHAN4( ncv1->color, c[1] );
1005   COPY_CHAN4( ncv2->color, c[2] );
1006}
1007
1008
1009
1010#ifdef DEBUG
1011
1012/* record the current triangle function name */
1013const char *_mesa_triFuncName = NULL;
1014
1015#define USE(triFunc)				\
1016do {						\
1017    _mesa_triFuncName = #triFunc;		\
1018    /*printf("%s\n", _mesa_triFuncName);*/	\
1019    swrast->Triangle = triFunc;			\
1020} while (0)
1021
1022#else
1023
1024#define USE(triFunc)  swrast->Triangle = triFunc;
1025
1026#endif
1027
1028
1029
1030
1031/*
1032 * Determine which triangle rendering function to use given the current
1033 * rendering context.
1034 *
1035 * Please update the summary flag _SWRAST_NEW_TRIANGLE if you add or
1036 * remove tests to this code.
1037 */
1038void
1039_swrast_choose_triangle( GLcontext *ctx )
1040{
1041   SWcontext *swrast = SWRAST_CONTEXT(ctx);
1042   const GLboolean rgbmode = ctx->Visual.rgbMode;
1043
1044   if (ctx->Polygon.CullFlag &&
1045       ctx->Polygon.CullFaceMode == GL_FRONT_AND_BACK) {
1046      USE(nodraw_triangle);
1047      return;
1048   }
1049
1050   if (ctx->RenderMode==GL_RENDER) {
1051
1052      if (ctx->Polygon.SmoothFlag) {
1053         _swrast_set_aa_triangle_function(ctx);
1054         ASSERT(swrast->Triangle);
1055         return;
1056      }
1057
1058      /* special case for occlusion testing */
1059      if (ctx->Query.CurrentOcclusionObject &&
1060          ctx->Depth.Test &&
1061          ctx->Depth.Mask == GL_FALSE &&
1062          ctx->Depth.Func == GL_LESS &&
1063          !ctx->Stencil.Enabled) {
1064         if ((rgbmode &&
1065              ctx->Color.ColorMask[0] == 0 &&
1066              ctx->Color.ColorMask[1] == 0 &&
1067              ctx->Color.ColorMask[2] == 0 &&
1068              ctx->Color.ColorMask[3] == 0)
1069             ||
1070             (!rgbmode && ctx->Color.IndexMask == 0)) {
1071            USE(occlusion_zless_triangle);
1072            return;
1073         }
1074      }
1075
1076      if (ctx->Texture._EnabledCoordUnits || ctx->FragmentProgram._Active || ctx->ATIFragmentShader._Enabled) {
1077         /* Ugh, we do a _lot_ of tests to pick the best textured tri func */
1078	 const struct gl_texture_object *texObj2D;
1079         const struct gl_texture_image *texImg;
1080         GLenum minFilter, magFilter, envMode;
1081         GLint format;
1082         texObj2D = ctx->Texture.Unit[0].Current2D;
1083         texImg = texObj2D ? texObj2D->Image[0][texObj2D->BaseLevel] : NULL;
1084         format = texImg ? texImg->TexFormat->MesaFormat : -1;
1085         minFilter = texObj2D ? texObj2D->MinFilter : (GLenum) 0;
1086         magFilter = texObj2D ? texObj2D->MagFilter : (GLenum) 0;
1087         envMode = ctx->Texture.Unit[0].EnvMode;
1088
1089         /* First see if we can use an optimized 2-D texture function */
1090         if (ctx->Texture._EnabledCoordUnits == 0x1
1091             && !ctx->FragmentProgram._Active
1092	     && !ctx->ATIFragmentShader._Enabled
1093             && ctx->Texture.Unit[0]._ReallyEnabled == TEXTURE_2D_BIT
1094             && texObj2D->WrapS == GL_REPEAT
1095	     && texObj2D->WrapT == GL_REPEAT
1096             && texObj2D->_IsPowerOfTwo
1097             && texImg->Border == 0
1098             && texImg->Width == texImg->RowStride
1099             && (format == MESA_FORMAT_RGB || format == MESA_FORMAT_RGBA)
1100	     && minFilter == magFilter
1101	     && ctx->Light.Model.ColorControl == GL_SINGLE_COLOR
1102	     && ctx->Texture.Unit[0].EnvMode != GL_COMBINE_EXT) {
1103	    if (ctx->Hint.PerspectiveCorrection==GL_FASTEST) {
1104	       if (minFilter == GL_NEAREST
1105		   && format == MESA_FORMAT_RGB
1106		   && (envMode == GL_REPLACE || envMode == GL_DECAL)
1107		   && ((swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)
1108			&& ctx->Depth.Func == GL_LESS
1109			&& ctx->Depth.Mask == GL_TRUE)
1110		       || swrast->_RasterMask == TEXTURE_BIT)
1111		   && ctx->Polygon.StippleFlag == GL_FALSE
1112                   && ctx->Visual.depthBits <= 16) {
1113		  if (swrast->_RasterMask == (DEPTH_BIT | TEXTURE_BIT)) {
1114		     USE(simple_z_textured_triangle);
1115		  }
1116		  else {
1117		     USE(simple_textured_triangle);
1118		  }
1119	       }
1120	       else {
1121#if (CHAN_BITS == 16 || CHAN_BITS == 32)
1122                  USE(general_textured_triangle);
1123#else
1124                  USE(affine_textured_triangle);
1125#endif
1126	       }
1127	    }
1128	    else {
1129#if (CHAN_BITS == 16 || CHAN_BITS == 32)
1130               USE(general_textured_triangle);
1131#else
1132               USE(persp_textured_triangle);
1133#endif
1134	    }
1135	 }
1136         else {
1137            /* general case textured triangles */
1138            if (ctx->Texture._EnabledCoordUnits > 1) {
1139               USE(multitextured_triangle);
1140            }
1141            else {
1142               USE(general_textured_triangle);
1143            }
1144         }
1145      }
1146      else {
1147         ASSERT(!ctx->Texture._EnabledCoordUnits);
1148	 if (ctx->Light.ShadeModel==GL_SMOOTH) {
1149	    /* smooth shaded, no texturing, stippled or some raster ops */
1150            if (rgbmode) {
1151	       USE(smooth_rgba_triangle);
1152            }
1153            else {
1154               USE(smooth_ci_triangle);
1155            }
1156	 }
1157	 else {
1158	    /* flat shaded, no texturing, stippled or some raster ops */
1159            if (rgbmode) {
1160	       USE(flat_rgba_triangle);
1161            }
1162            else {
1163               USE(flat_ci_triangle);
1164            }
1165	 }
1166      }
1167   }
1168   else if (ctx->RenderMode==GL_FEEDBACK) {
1169      USE(_swrast_feedback_triangle);
1170   }
1171   else {
1172      /* GL_SELECT mode */
1173      USE(_swrast_select_triangle);
1174   }
1175}
1176