sp_tex_sample.c revision aa5db684382bd8662a83ca09ed000e4a5a1013f9
1/**************************************************************************
2 *
3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
4 * All Rights Reserved.
5 * Copyright 2008 VMware, Inc.  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
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
22 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
23 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
24 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
25 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28
29/**
30 * Texture sampling
31 *
32 * Authors:
33 *   Brian Paul
34 */
35
36#include "sp_context.h"
37#include "sp_quad.h"
38#include "sp_surface.h"
39#include "sp_texture.h"
40#include "sp_tex_sample.h"
41#include "sp_tile_cache.h"
42#include "pipe/p_context.h"
43#include "pipe/p_defines.h"
44#include "util/u_math.h"
45#include "util/u_memory.h"
46
47
48
49/*
50 * Note, the FRAC macro has to work perfectly.  Otherwise you'll sometimes
51 * see 1-pixel bands of improperly weighted linear-filtered textures.
52 * The tests/texwrap.c demo is a good test.
53 * Also note, FRAC(x) doesn't truly return the fractional part of x for x < 0.
54 * Instead, if x < 0 then FRAC(x) = 1 - true_frac(x).
55 */
56#define FRAC(f)  ((f) - util_ifloor(f))
57
58
59/**
60 * Linear interpolation macro
61 */
62static INLINE float
63lerp(float a, float v0, float v1)
64{
65   return v0 + a * (v1 - v0);
66}
67
68
69/**
70 * Do 2D/biliner interpolation of float values.
71 * v00, v10, v01 and v11 are typically four texture samples in a square/box.
72 * a and b are the horizontal and vertical interpolants.
73 * It's important that this function is inlined when compiled with
74 * optimization!  If we find that's not true on some systems, convert
75 * to a macro.
76 */
77static INLINE float
78lerp_2d(float a, float b,
79        float v00, float v10, float v01, float v11)
80{
81   const float temp0 = lerp(a, v00, v10);
82   const float temp1 = lerp(a, v01, v11);
83   return lerp(b, temp0, temp1);
84}
85
86
87/**
88 * As above, but 3D interpolation of 8 values.
89 */
90static INLINE float
91lerp_3d(float a, float b, float c,
92        float v000, float v100, float v010, float v110,
93        float v001, float v101, float v011, float v111)
94{
95   const float temp0 = lerp_2d(a, b, v000, v100, v010, v110);
96   const float temp1 = lerp_2d(a, b, v001, v101, v011, v111);
97   return lerp(c, temp0, temp1);
98}
99
100
101
102/**
103 * If A is a signed integer, A % B doesn't give the right value for A < 0
104 * (in terms of texture repeat).  Just casting to unsigned fixes that.
105 */
106#define REMAINDER(A, B) ((unsigned) (A) % (unsigned) (B))
107
108
109/**
110 * Apply texture coord wrapping mode and return integer texture indexes
111 * for a vector of four texcoords (S or T or P).
112 * \param wrapMode  PIPE_TEX_WRAP_x
113 * \param s  the incoming texcoords
114 * \param size  the texture image size
115 * \param icoord  returns the integer texcoords
116 * \return  integer texture index
117 */
118static INLINE void
119nearest_texcoord_4(unsigned wrapMode, const float s[4], unsigned size,
120                   int icoord[4])
121{
122   uint ch;
123   switch (wrapMode) {
124   case PIPE_TEX_WRAP_REPEAT:
125      /* s limited to [0,1) */
126      /* i limited to [0,size-1] */
127      for (ch = 0; ch < 4; ch++) {
128         int i = util_ifloor(s[ch] * size);
129         icoord[ch] = REMAINDER(i, size);
130      }
131      return;
132   case PIPE_TEX_WRAP_CLAMP:
133      /* s limited to [0,1] */
134      /* i limited to [0,size-1] */
135      for (ch = 0; ch < 4; ch++) {
136         if (s[ch] <= 0.0F)
137            icoord[ch] = 0;
138         else if (s[ch] >= 1.0F)
139            icoord[ch] = size - 1;
140         else
141            icoord[ch] = util_ifloor(s[ch] * size);
142      }
143      return;
144   case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
145      {
146         /* s limited to [min,max] */
147         /* i limited to [0, size-1] */
148         const float min = 1.0F / (2.0F * size);
149         const float max = 1.0F - min;
150         for (ch = 0; ch < 4; ch++) {
151            if (s[ch] < min)
152               icoord[ch] = 0;
153            else if (s[ch] > max)
154               icoord[ch] = size - 1;
155            else
156               icoord[ch] = util_ifloor(s[ch] * size);
157         }
158      }
159      return;
160   case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
161      {
162         /* s limited to [min,max] */
163         /* i limited to [-1, size] */
164         const float min = -1.0F / (2.0F * size);
165         const float max = 1.0F - min;
166         for (ch = 0; ch < 4; ch++) {
167            if (s[ch] <= min)
168               icoord[ch] = -1;
169            else if (s[ch] >= max)
170               icoord[ch] = size;
171            else
172               icoord[ch] = util_ifloor(s[ch] * size);
173         }
174      }
175      return;
176   case PIPE_TEX_WRAP_MIRROR_REPEAT:
177      {
178         const float min = 1.0F / (2.0F * size);
179         const float max = 1.0F - min;
180         for (ch = 0; ch < 4; ch++) {
181            const int flr = util_ifloor(s[ch]);
182            float u;
183            if (flr & 1)
184               u = 1.0F - (s[ch] - (float) flr);
185            else
186               u = s[ch] - (float) flr;
187            if (u < min)
188               icoord[ch] = 0;
189            else if (u > max)
190               icoord[ch] = size - 1;
191            else
192               icoord[ch] = util_ifloor(u * size);
193         }
194      }
195      return;
196   case PIPE_TEX_WRAP_MIRROR_CLAMP:
197      for (ch = 0; ch < 4; ch++) {
198         /* s limited to [0,1] */
199         /* i limited to [0,size-1] */
200         const float u = fabsf(s[ch]);
201         if (u <= 0.0F)
202            icoord[ch] = 0;
203         else if (u >= 1.0F)
204            icoord[ch] = size - 1;
205         else
206            icoord[ch] = util_ifloor(u * size);
207      }
208      return;
209   case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
210      {
211         /* s limited to [min,max] */
212         /* i limited to [0, size-1] */
213         const float min = 1.0F / (2.0F * size);
214         const float max = 1.0F - min;
215         for (ch = 0; ch < 4; ch++) {
216            const float u = fabsf(s[ch]);
217            if (u < min)
218               icoord[ch] = 0;
219            else if (u > max)
220               icoord[ch] = size - 1;
221            else
222               icoord[ch] = util_ifloor(u * size);
223         }
224      }
225      return;
226   case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
227      {
228         /* s limited to [min,max] */
229         /* i limited to [0, size-1] */
230         const float min = -1.0F / (2.0F * size);
231         const float max = 1.0F - min;
232         for (ch = 0; ch < 4; ch++) {
233            const float u = fabsf(s[ch]);
234            if (u < min)
235               icoord[ch] = -1;
236            else if (u > max)
237               icoord[ch] = size;
238            else
239               icoord[ch] = util_ifloor(u * size);
240         }
241      }
242      return;
243   default:
244      assert(0);
245   }
246}
247
248
249/**
250 * Used to compute texel locations for linear sampling for four texcoords.
251 * \param wrapMode  PIPE_TEX_WRAP_x
252 * \param s  the texcoords
253 * \param size  the texture image size
254 * \param icoord0  returns first texture indexes
255 * \param icoord1  returns second texture indexes (usually icoord0 + 1)
256 * \param w  returns blend factor/weight between texture indexes
257 * \param icoord  returns the computed integer texture coords
258 */
259static INLINE void
260linear_texcoord_4(unsigned wrapMode, const float s[4], unsigned size,
261                  int icoord0[4], int icoord1[4], float w[4])
262{
263   uint ch;
264
265   switch (wrapMode) {
266   case PIPE_TEX_WRAP_REPEAT:
267      for (ch = 0; ch < 4; ch++) {
268         float u = s[ch] * size - 0.5F;
269         icoord0[ch] = REMAINDER(util_ifloor(u), size);
270         icoord1[ch] = REMAINDER(icoord0[ch] + 1, size);
271         w[ch] = FRAC(u);
272      }
273      break;;
274   case PIPE_TEX_WRAP_CLAMP:
275      for (ch = 0; ch < 4; ch++) {
276         float u = CLAMP(s[ch], 0.0F, 1.0F);
277         u = u * size - 0.5f;
278         icoord0[ch] = util_ifloor(u);
279         icoord1[ch] = icoord0[ch] + 1;
280         w[ch] = FRAC(u);
281      }
282      break;;
283   case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
284      for (ch = 0; ch < 4; ch++) {
285         float u = CLAMP(s[ch], 0.0F, 1.0F);
286         u = u * size - 0.5f;
287         icoord0[ch] = util_ifloor(u);
288         icoord1[ch] = icoord0[ch] + 1;
289         if (icoord0[ch] < 0)
290            icoord0[ch] = 0;
291         if (icoord1[ch] >= (int) size)
292            icoord1[ch] = size - 1;
293         w[ch] = FRAC(u);
294      }
295      break;;
296   case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
297      {
298         const float min = -1.0F / (2.0F * size);
299         const float max = 1.0F - min;
300         for (ch = 0; ch < 4; ch++) {
301            float u = CLAMP(s[ch], min, max);
302            u = u * size - 0.5f;
303            icoord0[ch] = util_ifloor(u);
304            icoord1[ch] = icoord0[ch] + 1;
305            w[ch] = FRAC(u);
306         }
307      }
308      break;;
309   case PIPE_TEX_WRAP_MIRROR_REPEAT:
310      for (ch = 0; ch < 4; ch++) {
311         const int flr = util_ifloor(s[ch]);
312         float u;
313         if (flr & 1)
314            u = 1.0F - (s[ch] - (float) flr);
315         else
316            u = s[ch] - (float) flr;
317         u = u * size - 0.5F;
318         icoord0[ch] = util_ifloor(u);
319         icoord1[ch] = icoord0[ch] + 1;
320         if (icoord0[ch] < 0)
321            icoord0[ch] = 0;
322         if (icoord1[ch] >= (int) size)
323            icoord1[ch] = size - 1;
324         w[ch] = FRAC(u);
325      }
326      break;;
327   case PIPE_TEX_WRAP_MIRROR_CLAMP:
328      for (ch = 0; ch < 4; ch++) {
329         float u = fabsf(s[ch]);
330         if (u >= 1.0F)
331            u = (float) size;
332         else
333            u *= size;
334         u -= 0.5F;
335         icoord0[ch] = util_ifloor(u);
336         icoord1[ch] = icoord0[ch] + 1;
337         w[ch] = FRAC(u);
338      }
339      break;;
340   case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
341      for (ch = 0; ch < 4; ch++) {
342         float u = fabsf(s[ch]);
343         if (u >= 1.0F)
344            u = (float) size;
345         else
346            u *= size;
347         u -= 0.5F;
348         icoord0[ch] = util_ifloor(u);
349         icoord1[ch] = icoord0[ch] + 1;
350         if (icoord0[ch] < 0)
351            icoord0[ch] = 0;
352         if (icoord1[ch] >= (int) size)
353            icoord1[ch] = size - 1;
354         w[ch] = FRAC(u);
355      }
356      break;;
357   case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
358      {
359         const float min = -1.0F / (2.0F * size);
360         const float max = 1.0F - min;
361         for (ch = 0; ch < 4; ch++) {
362            float u = fabsf(s[ch]);
363            if (u <= min)
364               u = min * size;
365            else if (u >= max)
366               u = max * size;
367            else
368               u *= size;
369            u -= 0.5F;
370            icoord0[ch] = util_ifloor(u);
371            icoord1[ch] = icoord0[ch] + 1;
372            w[ch] = FRAC(u);
373         }
374      }
375      break;;
376   default:
377      assert(0);
378   }
379}
380
381
382/**
383 * For RECT textures / unnormalized texcoords
384 * Only a subset of wrap modes supported.
385 */
386static INLINE void
387nearest_texcoord_unnorm_4(unsigned wrapMode, const float s[4], unsigned size,
388                          int icoord[4])
389{
390   uint ch;
391   switch (wrapMode) {
392   case PIPE_TEX_WRAP_CLAMP:
393      for (ch = 0; ch < 4; ch++) {
394         int i = util_ifloor(s[ch]);
395         icoord[ch]= CLAMP(i, 0, (int) size-1);
396      }
397      return;
398   case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
399      /* fall-through */
400   case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
401      for (ch = 0; ch < 4; ch++) {
402         icoord[ch]= util_ifloor( CLAMP(s[ch], 0.5F, (float) size - 0.5F) );
403      }
404      return;
405   default:
406      assert(0);
407   }
408}
409
410
411/**
412 * For RECT textures / unnormalized texcoords.
413 * Only a subset of wrap modes supported.
414 */
415static INLINE void
416linear_texcoord_unnorm_4(unsigned wrapMode, const float s[4], unsigned size,
417                         int icoord0[4], int icoord1[4], float w[4])
418{
419   uint ch;
420   switch (wrapMode) {
421   case PIPE_TEX_WRAP_CLAMP:
422      for (ch = 0; ch < 4; ch++) {
423         /* Not exactly what the spec says, but it matches NVIDIA output */
424         float u = CLAMP(s[ch] - 0.5F, 0.0f, (float) size - 1.0f);
425         icoord0[ch] = util_ifloor(u);
426         icoord1[ch] = icoord0[ch] + 1;
427         w[ch] = FRAC(u);
428      }
429      return;
430   case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
431      /* fall-through */
432   case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
433      for (ch = 0; ch < 4; ch++) {
434         float u = CLAMP(s[ch], 0.5F, (float) size - 0.5F);
435         u -= 0.5F;
436         icoord0[ch] = util_ifloor(u);
437         icoord1[ch] = icoord0[ch] + 1;
438         if (icoord1[ch] > (int) size - 1)
439            icoord1[ch] = size - 1;
440         w[ch] = FRAC(u);
441      }
442      break;
443   default:
444      assert(0);
445   }
446}
447
448
449static unsigned
450choose_cube_face(float rx, float ry, float rz, float *newS, float *newT)
451{
452   /*
453      major axis
454      direction     target                             sc     tc    ma
455      ----------    -------------------------------    ---    ---   ---
456       +rx          TEXTURE_CUBE_MAP_POSITIVE_X_EXT    -rz    -ry   rx
457       -rx          TEXTURE_CUBE_MAP_NEGATIVE_X_EXT    +rz    -ry   rx
458       +ry          TEXTURE_CUBE_MAP_POSITIVE_Y_EXT    +rx    +rz   ry
459       -ry          TEXTURE_CUBE_MAP_NEGATIVE_Y_EXT    +rx    -rz   ry
460       +rz          TEXTURE_CUBE_MAP_POSITIVE_Z_EXT    +rx    -ry   rz
461       -rz          TEXTURE_CUBE_MAP_NEGATIVE_Z_EXT    -rx    -ry   rz
462   */
463   const float arx = fabsf(rx), ary = fabsf(ry), arz = fabsf(rz);
464   unsigned face;
465   float sc, tc, ma;
466
467   if (arx > ary && arx > arz) {
468      if (rx >= 0.0F) {
469         face = PIPE_TEX_FACE_POS_X;
470         sc = -rz;
471         tc = -ry;
472         ma = arx;
473      }
474      else {
475         face = PIPE_TEX_FACE_NEG_X;
476         sc = rz;
477         tc = -ry;
478         ma = arx;
479      }
480   }
481   else if (ary > arx && ary > arz) {
482      if (ry >= 0.0F) {
483         face = PIPE_TEX_FACE_POS_Y;
484         sc = rx;
485         tc = rz;
486         ma = ary;
487      }
488      else {
489         face = PIPE_TEX_FACE_NEG_Y;
490         sc = rx;
491         tc = -rz;
492         ma = ary;
493      }
494   }
495   else {
496      if (rz > 0.0F) {
497         face = PIPE_TEX_FACE_POS_Z;
498         sc = rx;
499         tc = -ry;
500         ma = arz;
501      }
502      else {
503         face = PIPE_TEX_FACE_NEG_Z;
504         sc = -rx;
505         tc = -ry;
506         ma = arz;
507      }
508   }
509
510   *newS = ( sc / ma + 1.0F ) * 0.5F;
511   *newT = ( tc / ma + 1.0F ) * 0.5F;
512
513   return face;
514}
515
516
517/**
518 * Examine the quad's texture coordinates to compute the partial
519 * derivatives w.r.t X and Y, then compute lambda (level of detail).
520 *
521 * This is only done for fragment shaders, not vertex shaders.
522 */
523static float
524compute_lambda(const struct pipe_texture *tex,
525               const struct pipe_sampler_state *sampler,
526               const float s[QUAD_SIZE],
527               const float t[QUAD_SIZE],
528               const float p[QUAD_SIZE],
529               float lodbias)
530{
531   float rho, lambda;
532
533   assert(sampler->normalized_coords);
534
535   assert(s);
536   {
537      float dsdx = s[QUAD_BOTTOM_RIGHT] - s[QUAD_BOTTOM_LEFT];
538      float dsdy = s[QUAD_TOP_LEFT]     - s[QUAD_BOTTOM_LEFT];
539      dsdx = fabsf(dsdx);
540      dsdy = fabsf(dsdy);
541      rho = MAX2(dsdx, dsdy) * tex->width[0];
542   }
543   if (t) {
544      float dtdx = t[QUAD_BOTTOM_RIGHT] - t[QUAD_BOTTOM_LEFT];
545      float dtdy = t[QUAD_TOP_LEFT]     - t[QUAD_BOTTOM_LEFT];
546      float max;
547      dtdx = fabsf(dtdx);
548      dtdy = fabsf(dtdy);
549      max = MAX2(dtdx, dtdy) * tex->height[0];
550      rho = MAX2(rho, max);
551   }
552   if (p) {
553      float dpdx = p[QUAD_BOTTOM_RIGHT] - p[QUAD_BOTTOM_LEFT];
554      float dpdy = p[QUAD_TOP_LEFT]     - p[QUAD_BOTTOM_LEFT];
555      float max;
556      dpdx = fabsf(dpdx);
557      dpdy = fabsf(dpdy);
558      max = MAX2(dpdx, dpdy) * tex->depth[0];
559      rho = MAX2(rho, max);
560   }
561
562   lambda = util_fast_log2(rho);
563   lambda += lodbias + sampler->lod_bias;
564   lambda = CLAMP(lambda, sampler->min_lod, sampler->max_lod);
565
566   return lambda;
567}
568
569
570/**
571 * Do several things here:
572 * 1. Compute lambda from the texcoords, if needed
573 * 2. Determine if we're minifying or magnifying
574 * 3. If minifying, choose mipmap levels
575 * 4. Return image filter to use within mipmap images
576 * \param level0  Returns first mipmap level to sample from
577 * \param level1  Returns second mipmap level to sample from
578 * \param levelBlend  Returns blend factor between levels, in [0,1]
579 * \param imgFilter  Returns either the min or mag filter, depending on lambda
580 */
581static void
582choose_mipmap_levels(const struct pipe_texture *texture,
583                     const struct pipe_sampler_state *sampler,
584                     const float s[QUAD_SIZE],
585                     const float t[QUAD_SIZE],
586                     const float p[QUAD_SIZE],
587                     boolean computeLambda,
588                     float lodbias,
589                     unsigned *level0, unsigned *level1, float *levelBlend,
590                     unsigned *imgFilter)
591{
592   if (sampler->min_mip_filter == PIPE_TEX_MIPFILTER_NONE) {
593      /* no mipmap selection needed */
594      *level0 = *level1 = CLAMP((int) sampler->min_lod,
595                                0, (int) texture->last_level);
596
597      if (sampler->min_img_filter != sampler->mag_img_filter) {
598         /* non-mipmapped texture, but still need to determine if doing
599          * minification or magnification.
600          */
601         float lambda = compute_lambda(texture, sampler, s, t, p, lodbias);
602         if (lambda <= 0.0) {
603            *imgFilter = sampler->mag_img_filter;
604         }
605         else {
606            *imgFilter = sampler->min_img_filter;
607         }
608      }
609      else {
610         *imgFilter = sampler->mag_img_filter;
611      }
612   }
613   else {
614      float lambda;
615
616      if (computeLambda)
617         /* fragment shader */
618         lambda = compute_lambda(texture, sampler, s, t, p, lodbias);
619      else
620         /* vertex shader */
621         lambda = lodbias; /* not really a bias, but absolute LOD */
622
623      if (lambda <= 0.0) { /* XXX threshold depends on the filter */
624         /* magnifying */
625         *imgFilter = sampler->mag_img_filter;
626         *level0 = *level1 = 0;
627      }
628      else {
629         /* minifying */
630         *imgFilter = sampler->min_img_filter;
631
632         /* choose mipmap level(s) and compute the blend factor between them */
633         if (sampler->min_mip_filter == PIPE_TEX_MIPFILTER_NEAREST) {
634            /* Nearest mipmap level */
635            const int lvl = (int) (lambda + 0.5);
636            *level0 =
637            *level1 = CLAMP(lvl, 0, (int) texture->last_level);
638         }
639         else {
640            /* Linear interpolation between mipmap levels */
641            const int lvl = (int) lambda;
642            *level0 = CLAMP(lvl,     0, (int) texture->last_level);
643            *level1 = CLAMP(lvl + 1, 0, (int) texture->last_level);
644            *levelBlend = FRAC(lambda);  /* blending weight between levels */
645         }
646      }
647   }
648}
649
650
651/**
652 * Get a texel from a texture, using the texture tile cache.
653 *
654 * \param face  the cube face in 0..5
655 * \param level  the mipmap level
656 * \param x  the x coord of texel within 2D image
657 * \param y  the y coord of texel within 2D image
658 * \param z  which slice of a 3D texture
659 * \param rgba  the quad to put the texel/color into
660 * \param j  which element of the rgba quad to write to
661 *
662 * XXX maybe move this into sp_tile_cache.c and merge with the
663 * sp_get_cached_tile_tex() function.  Also, get 4 texels instead of 1...
664 */
665static void
666get_texel(const struct tgsi_sampler *tgsi_sampler,
667          unsigned face, unsigned level, int x, int y, int z,
668          float rgba[NUM_CHANNELS][QUAD_SIZE], unsigned j)
669{
670   const struct sp_shader_sampler *samp = sp_shader_sampler(tgsi_sampler);
671   const struct pipe_texture *texture = samp->texture;
672   const struct pipe_sampler_state *sampler = samp->sampler;
673
674   if (x < 0 || x >= (int) texture->width[level] ||
675       y < 0 || y >= (int) texture->height[level] ||
676       z < 0 || z >= (int) texture->depth[level]) {
677      rgba[0][j] = sampler->border_color[0];
678      rgba[1][j] = sampler->border_color[1];
679      rgba[2][j] = sampler->border_color[2];
680      rgba[3][j] = sampler->border_color[3];
681   }
682   else {
683      const int tx = x % TILE_SIZE;
684      const int ty = y % TILE_SIZE;
685      const struct softpipe_cached_tile *tile
686         = sp_get_cached_tile_tex(samp->cache,
687                                  x, y, z, face, level);
688      rgba[0][j] = tile->data.color[ty][tx][0];
689      rgba[1][j] = tile->data.color[ty][tx][1];
690      rgba[2][j] = tile->data.color[ty][tx][2];
691      rgba[3][j] = tile->data.color[ty][tx][3];
692      if (0)
693      {
694         debug_printf("Get texel %f %f %f %f from %s\n",
695                      rgba[0][j], rgba[1][j], rgba[2][j], rgba[3][j],
696                      pf_name(texture->format));
697      }
698   }
699}
700
701
702/**
703 * Compare texcoord 'p' (aka R) against texture value 'rgba[0]'
704 * When we sampled the depth texture, the depth value was put into all
705 * RGBA channels.  We look at the red channel here.
706 * \param rgba  quad of (depth) texel values
707 * \param p  texture 'P' components for four pixels in quad
708 * \param j  which pixel in the quad to test [0..3]
709 */
710static INLINE void
711shadow_compare(const struct pipe_sampler_state *sampler,
712               float rgba[NUM_CHANNELS][QUAD_SIZE],
713               const float p[QUAD_SIZE],
714               uint j)
715{
716   int k;
717   switch (sampler->compare_func) {
718   case PIPE_FUNC_LESS:
719      k = p[j] < rgba[0][j];
720      break;
721   case PIPE_FUNC_LEQUAL:
722      k = p[j] <= rgba[0][j];
723      break;
724   case PIPE_FUNC_GREATER:
725      k = p[j] > rgba[0][j];
726      break;
727   case PIPE_FUNC_GEQUAL:
728      k = p[j] >= rgba[0][j];
729      break;
730   case PIPE_FUNC_EQUAL:
731      k = p[j] == rgba[0][j];
732      break;
733   case PIPE_FUNC_NOTEQUAL:
734      k = p[j] != rgba[0][j];
735      break;
736   case PIPE_FUNC_ALWAYS:
737      k = 1;
738      break;
739   case PIPE_FUNC_NEVER:
740      k = 0;
741      break;
742   default:
743      k = 0;
744      assert(0);
745      break;
746   }
747
748   /* XXX returning result for default GL_DEPTH_TEXTURE_MODE = GL_LUMINANCE */
749   rgba[0][j] = rgba[1][j] = rgba[2][j] = (float) k;
750   rgba[3][j] = 1.0F;
751}
752
753
754/**
755 * As above, but do four z/texture comparisons.
756 */
757static INLINE void
758shadow_compare4(const struct pipe_sampler_state *sampler,
759                float rgba[NUM_CHANNELS][QUAD_SIZE],
760                const float p[QUAD_SIZE])
761{
762   int j, k0, k1, k2, k3;
763   float val;
764
765   /* compare four texcoords vs. four texture samples */
766   switch (sampler->compare_func) {
767   case PIPE_FUNC_LESS:
768      k0 = p[0] < rgba[0][0];
769      k1 = p[1] < rgba[0][1];
770      k2 = p[2] < rgba[0][2];
771      k3 = p[3] < rgba[0][3];
772      break;
773   case PIPE_FUNC_LEQUAL:
774      k0 = p[0] <= rgba[0][0];
775      k1 = p[1] <= rgba[0][1];
776      k2 = p[2] <= rgba[0][2];
777      k3 = p[3] <= rgba[0][3];
778      break;
779   case PIPE_FUNC_GREATER:
780      k0 = p[0] > rgba[0][0];
781      k1 = p[1] > rgba[0][1];
782      k2 = p[2] > rgba[0][2];
783      k3 = p[3] > rgba[0][3];
784      break;
785   case PIPE_FUNC_GEQUAL:
786      k0 = p[0] >= rgba[0][0];
787      k1 = p[1] >= rgba[0][1];
788      k2 = p[2] >= rgba[0][2];
789      k3 = p[3] >= rgba[0][3];
790      break;
791   case PIPE_FUNC_EQUAL:
792      k0 = p[0] == rgba[0][0];
793      k1 = p[1] == rgba[0][1];
794      k2 = p[2] == rgba[0][2];
795      k3 = p[3] == rgba[0][3];
796      break;
797   case PIPE_FUNC_NOTEQUAL:
798      k0 = p[0] != rgba[0][0];
799      k1 = p[1] != rgba[0][1];
800      k2 = p[2] != rgba[0][2];
801      k3 = p[3] != rgba[0][3];
802      break;
803   case PIPE_FUNC_ALWAYS:
804      k0 = k1 = k2 = k3 = 1;
805      break;
806   case PIPE_FUNC_NEVER:
807      k0 = k1 = k2 = k3 = 0;
808      break;
809   default:
810      k0 = k1 = k2 = k3 = 0;
811      assert(0);
812      break;
813   }
814
815   /* convert four pass/fail values to an intensity in [0,1] */
816   val = 0.25F * (k0 + k1 + k2 + k3);
817
818   /* XXX returning result for default GL_DEPTH_TEXTURE_MODE = GL_LUMINANCE */
819   for (j = 0; j < 4; j++) {
820      rgba[0][j] = rgba[1][j] = rgba[2][j] = val;
821      rgba[3][j] = 1.0F;
822   }
823}
824
825
826/**
827 * Common code for sampling 1D/2D/cube textures.
828 * Could probably extend for 3D...
829 */
830static void
831sp_get_samples_2d_common(const struct tgsi_sampler *tgsi_sampler,
832                         const float s[QUAD_SIZE],
833                         const float t[QUAD_SIZE],
834                         const float p[QUAD_SIZE],
835                         boolean computeLambda,
836                         float lodbias,
837                         float rgba[NUM_CHANNELS][QUAD_SIZE],
838                         const unsigned faces[4])
839{
840   const struct sp_shader_sampler *samp = sp_shader_sampler(tgsi_sampler);
841   const struct pipe_texture *texture = samp->texture;
842   const struct pipe_sampler_state *sampler = samp->sampler;
843   unsigned level0, level1, j, imgFilter;
844   int width, height;
845   float levelBlend;
846
847   choose_mipmap_levels(texture, sampler, s, t, p, computeLambda, lodbias,
848                        &level0, &level1, &levelBlend, &imgFilter);
849
850   assert(sampler->normalized_coords);
851
852   width = texture->width[level0];
853   height = texture->height[level0];
854
855   assert(width > 0);
856
857   switch (imgFilter) {
858   case PIPE_TEX_FILTER_NEAREST:
859      {
860         int x[4], y[4];
861         nearest_texcoord_4(sampler->wrap_s, s, width, x);
862         nearest_texcoord_4(sampler->wrap_t, t, height, y);
863
864         for (j = 0; j < QUAD_SIZE; j++) {
865            get_texel(tgsi_sampler, faces[j], level0, x[j], y[j], 0, rgba, j);
866            if (sampler->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
867               shadow_compare(sampler, rgba, p, j);
868            }
869
870            if (level0 != level1) {
871               /* get texels from second mipmap level and blend */
872               float rgba2[4][4];
873               unsigned c;
874               x[j] /= 2;
875               y[j] /= 2;
876               get_texel(tgsi_sampler, faces[j], level1, x[j], y[j], 0,
877                         rgba2, j);
878               if (sampler->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE){
879                  shadow_compare(sampler, rgba2, p, j);
880               }
881
882               for (c = 0; c < NUM_CHANNELS; c++) {
883                  rgba[c][j] = lerp(levelBlend, rgba[c][j], rgba2[c][j]);
884               }
885            }
886         }
887      }
888      break;
889   case PIPE_TEX_FILTER_LINEAR:
890   case PIPE_TEX_FILTER_ANISO:
891      {
892         int x0[4], y0[4], x1[4], y1[4];
893         float xw[4], yw[4]; /* weights */
894
895         linear_texcoord_4(sampler->wrap_s, s, width, x0, x1, xw);
896         linear_texcoord_4(sampler->wrap_t, t, height, y0, y1, yw);
897
898         for (j = 0; j < QUAD_SIZE; j++) {
899            float tx[4][4]; /* texels */
900            int c;
901            get_texel(tgsi_sampler, faces[j], level0, x0[j], y0[j], 0, tx, 0);
902            get_texel(tgsi_sampler, faces[j], level0, x1[j], y0[j], 0, tx, 1);
903            get_texel(tgsi_sampler, faces[j], level0, x0[j], y1[j], 0, tx, 2);
904            get_texel(tgsi_sampler, faces[j], level0, x1[j], y1[j], 0, tx, 3);
905            if (sampler->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
906               shadow_compare4(sampler, tx, p);
907            }
908
909            /* interpolate R, G, B, A */
910            for (c = 0; c < 4; c++) {
911               rgba[c][j] = lerp_2d(xw[j], yw[j],
912                                    tx[c][0], tx[c][1],
913                                    tx[c][2], tx[c][3]);
914            }
915
916            if (level0 != level1) {
917               /* get texels from second mipmap level and blend */
918               float rgba2[4][4];
919               x0[j] /= 2;
920               y0[j] /= 2;
921               x1[j] /= 2;
922               y1[j] /= 2;
923               get_texel(tgsi_sampler, faces[j], level1, x0[j], y0[j], 0, tx, 0);
924               get_texel(tgsi_sampler, faces[j], level1, x1[j], y0[j], 0, tx, 1);
925               get_texel(tgsi_sampler, faces[j], level1, x0[j], y1[j], 0, tx, 2);
926               get_texel(tgsi_sampler, faces[j], level1, x1[j], y1[j], 0, tx, 3);
927               if (sampler->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE){
928                  shadow_compare4(sampler, tx, p);
929               }
930
931               /* interpolate R, G, B, A */
932               for (c = 0; c < 4; c++) {
933                  rgba2[c][j] = lerp_2d(xw[j], yw[j],
934                                        tx[c][0], tx[c][1], tx[c][2], tx[c][3]);
935               }
936
937               for (c = 0; c < NUM_CHANNELS; c++) {
938                  rgba[c][j] = lerp(levelBlend, rgba[c][j], rgba2[c][j]);
939               }
940            }
941         }
942      }
943      break;
944   default:
945      assert(0);
946   }
947}
948
949
950static INLINE void
951sp_get_samples_1d(const struct tgsi_sampler *sampler,
952                  const float s[QUAD_SIZE],
953                  const float t[QUAD_SIZE],
954                  const float p[QUAD_SIZE],
955                  boolean computeLambda,
956                  float lodbias,
957                  float rgba[NUM_CHANNELS][QUAD_SIZE])
958{
959   static const unsigned faces[4] = {0, 0, 0, 0};
960   static const float tzero[4] = {0, 0, 0, 0};
961   sp_get_samples_2d_common(sampler, s, tzero, NULL,
962                            computeLambda, lodbias, rgba, faces);
963}
964
965
966static INLINE void
967sp_get_samples_2d(const struct tgsi_sampler *sampler,
968                  const float s[QUAD_SIZE],
969                  const float t[QUAD_SIZE],
970                  const float p[QUAD_SIZE],
971                  boolean computeLambda,
972                  float lodbias,
973                  float rgba[NUM_CHANNELS][QUAD_SIZE])
974{
975   static const unsigned faces[4] = {0, 0, 0, 0};
976   sp_get_samples_2d_common(sampler, s, t, p,
977                            computeLambda, lodbias, rgba, faces);
978}
979
980
981static INLINE void
982sp_get_samples_3d(const struct tgsi_sampler *tgsi_sampler,
983                  const float s[QUAD_SIZE],
984                  const float t[QUAD_SIZE],
985                  const float p[QUAD_SIZE],
986                  boolean computeLambda,
987                  float lodbias,
988                  float rgba[NUM_CHANNELS][QUAD_SIZE])
989{
990   const struct sp_shader_sampler *samp = sp_shader_sampler(tgsi_sampler);
991   const struct pipe_texture *texture = samp->texture;
992   const struct pipe_sampler_state *sampler = samp->sampler;
993   /* get/map pipe_surfaces corresponding to 3D tex slices */
994   unsigned level0, level1, j, imgFilter;
995   int width, height, depth;
996   float levelBlend;
997   const uint face = 0;
998
999   choose_mipmap_levels(texture, sampler, s, t, p, computeLambda, lodbias,
1000                        &level0, &level1, &levelBlend, &imgFilter);
1001
1002   assert(sampler->normalized_coords);
1003
1004   width = texture->width[level0];
1005   height = texture->height[level0];
1006   depth = texture->depth[level0];
1007
1008   assert(width > 0);
1009   assert(height > 0);
1010   assert(depth > 0);
1011
1012   switch (imgFilter) {
1013   case PIPE_TEX_FILTER_NEAREST:
1014      {
1015         int x[4], y[4], z[4];
1016         nearest_texcoord_4(sampler->wrap_s, s, width, x);
1017         nearest_texcoord_4(sampler->wrap_t, t, height, y);
1018         nearest_texcoord_4(sampler->wrap_r, p, depth, z);
1019         for (j = 0; j < QUAD_SIZE; j++) {
1020            get_texel(tgsi_sampler, face, level0, x[j], y[j], z[j], rgba, j);
1021            if (level0 != level1) {
1022               /* get texels from second mipmap level and blend */
1023               float rgba2[4][4];
1024               unsigned c;
1025               x[j] /= 2;
1026               y[j] /= 2;
1027               z[j] /= 2;
1028               get_texel(tgsi_sampler, face, level1, x[j], y[j], z[j], rgba2, j);
1029               for (c = 0; c < NUM_CHANNELS; c++) {
1030                  rgba[c][j] = lerp(levelBlend, rgba2[c][j], rgba[c][j]);
1031               }
1032            }
1033         }
1034      }
1035      break;
1036   case PIPE_TEX_FILTER_LINEAR:
1037   case PIPE_TEX_FILTER_ANISO:
1038      {
1039         int x0[4], x1[4], y0[4], y1[4], z0[4], z1[4];
1040         float xw[4], yw[4], zw[4]; /* interpolation weights */
1041         linear_texcoord_4(sampler->wrap_s, s, width,  x0, x1, xw);
1042         linear_texcoord_4(sampler->wrap_t, t, height, y0, y1, yw);
1043         linear_texcoord_4(sampler->wrap_r, p, depth,  z0, z1, zw);
1044
1045         for (j = 0; j < QUAD_SIZE; j++) {
1046            int c;
1047            float tx0[4][4], tx1[4][4];
1048            get_texel(tgsi_sampler, face, level0, x0[j], y0[j], z0[j], tx0, 0);
1049            get_texel(tgsi_sampler, face, level0, x1[j], y0[j], z0[j], tx0, 1);
1050            get_texel(tgsi_sampler, face, level0, x0[j], y1[j], z0[j], tx0, 2);
1051            get_texel(tgsi_sampler, face, level0, x1[j], y1[j], z0[j], tx0, 3);
1052            get_texel(tgsi_sampler, face, level0, x0[j], y0[j], z1[j], tx1, 0);
1053            get_texel(tgsi_sampler, face, level0, x1[j], y0[j], z1[j], tx1, 1);
1054            get_texel(tgsi_sampler, face, level0, x0[j], y1[j], z1[j], tx1, 2);
1055            get_texel(tgsi_sampler, face, level0, x1[j], y1[j], z1[j], tx1, 3);
1056
1057            /* interpolate R, G, B, A */
1058            for (c = 0; c < 4; c++) {
1059               rgba[c][j] = lerp_3d(xw[j], yw[j], zw[j],
1060                                    tx0[c][0], tx0[c][1],
1061                                    tx0[c][2], tx0[c][3],
1062                                    tx1[c][0], tx1[c][1],
1063                                    tx1[c][2], tx1[c][3]);
1064            }
1065
1066            if (level0 != level1) {
1067               /* get texels from second mipmap level and blend */
1068               float rgba2[4][4];
1069               x0[j] /= 2;
1070               y0[j] /= 2;
1071               z0[j] /= 2;
1072               x1[j] /= 2;
1073               y1[j] /= 2;
1074               z1[j] /= 2;
1075               get_texel(tgsi_sampler, face, level1, x0[j], y0[j], z0[j], tx0, 0);
1076               get_texel(tgsi_sampler, face, level1, x1[j], y0[j], z0[j], tx0, 1);
1077               get_texel(tgsi_sampler, face, level1, x0[j], y1[j], z0[j], tx0, 2);
1078               get_texel(tgsi_sampler, face, level1, x1[j], y1[j], z0[j], tx0, 3);
1079               get_texel(tgsi_sampler, face, level1, x0[j], y0[j], z1[j], tx1, 0);
1080               get_texel(tgsi_sampler, face, level1, x1[j], y0[j], z1[j], tx1, 1);
1081               get_texel(tgsi_sampler, face, level1, x0[j], y1[j], z1[j], tx1, 2);
1082               get_texel(tgsi_sampler, face, level1, x1[j], y1[j], z1[j], tx1, 3);
1083
1084               /* interpolate R, G, B, A */
1085               for (c = 0; c < 4; c++) {
1086                  rgba2[c][j] = lerp_3d(xw[j], yw[j], zw[j],
1087                                        tx0[c][0], tx0[c][1],
1088                                        tx0[c][2], tx0[c][3],
1089                                        tx1[c][0], tx1[c][1],
1090                                        tx1[c][2], tx1[c][3]);
1091               }
1092
1093               /* blend mipmap levels */
1094               for (c = 0; c < NUM_CHANNELS; c++) {
1095                  rgba[c][j] = lerp(levelBlend, rgba[c][j], rgba2[c][j]);
1096               }
1097            }
1098         }
1099      }
1100      break;
1101   default:
1102      assert(0);
1103   }
1104}
1105
1106
1107static void
1108sp_get_samples_cube(const struct tgsi_sampler *sampler,
1109                    const float s[QUAD_SIZE],
1110                    const float t[QUAD_SIZE],
1111                    const float p[QUAD_SIZE],
1112                    boolean computeLambda,
1113                    float lodbias,
1114                    float rgba[NUM_CHANNELS][QUAD_SIZE])
1115{
1116   unsigned faces[QUAD_SIZE], j;
1117   float ssss[4], tttt[4];
1118   for (j = 0; j < QUAD_SIZE; j++) {
1119      faces[j] = choose_cube_face(s[j], t[j], p[j], ssss + j, tttt + j);
1120   }
1121   sp_get_samples_2d_common(sampler, ssss, tttt, NULL,
1122                            computeLambda, lodbias, rgba, faces);
1123}
1124
1125
1126static void
1127sp_get_samples_rect(const struct tgsi_sampler *tgsi_sampler,
1128                    const float s[QUAD_SIZE],
1129                    const float t[QUAD_SIZE],
1130                    const float p[QUAD_SIZE],
1131                    boolean computeLambda,
1132                    float lodbias,
1133                    float rgba[NUM_CHANNELS][QUAD_SIZE])
1134{
1135   const struct sp_shader_sampler *samp = sp_shader_sampler(tgsi_sampler);
1136   const struct pipe_texture *texture = samp->texture;
1137   const struct pipe_sampler_state *sampler = samp->sampler;
1138   const uint face = 0;
1139   unsigned level0, level1, j, imgFilter;
1140   int width, height;
1141   float levelBlend;
1142
1143   choose_mipmap_levels(texture, sampler, s, t, p, computeLambda, lodbias,
1144                        &level0, &level1, &levelBlend, &imgFilter);
1145
1146   /* texture RECTS cannot be mipmapped */
1147   assert(level0 == level1);
1148
1149   width = texture->width[level0];
1150   height = texture->height[level0];
1151
1152   assert(width > 0);
1153
1154   switch (imgFilter) {
1155   case PIPE_TEX_FILTER_NEAREST:
1156      {
1157         int x[4], y[4];
1158         nearest_texcoord_unnorm_4(sampler->wrap_s, s, width, x);
1159         nearest_texcoord_unnorm_4(sampler->wrap_t, t, height, y);
1160         for (j = 0; j < QUAD_SIZE; j++) {
1161            get_texel(tgsi_sampler, face, level0, x[j], y[j], 0, rgba, j);
1162            if (sampler->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
1163               shadow_compare(sampler, rgba, p, j);
1164            }
1165         }
1166      }
1167      break;
1168   case PIPE_TEX_FILTER_LINEAR:
1169   case PIPE_TEX_FILTER_ANISO:
1170      {
1171         int x0[4], y0[4], x1[4], y1[4];
1172         float xw[4], yw[4]; /* weights */
1173         linear_texcoord_unnorm_4(sampler->wrap_s, s, width,  x0, x1, xw);
1174         linear_texcoord_unnorm_4(sampler->wrap_t, t, height, y0, y1, yw);
1175         for (j = 0; j < QUAD_SIZE; j++) {
1176            float tx[4][4]; /* texels */
1177            int c;
1178            get_texel(tgsi_sampler, face, level0, x0[j], y0[j], 0, tx, 0);
1179            get_texel(tgsi_sampler, face, level0, x1[j], y0[j], 0, tx, 1);
1180            get_texel(tgsi_sampler, face, level0, x0[j], y1[j], 0, tx, 2);
1181            get_texel(tgsi_sampler, face, level0, x1[j], y1[j], 0, tx, 3);
1182            if (sampler->compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
1183               shadow_compare4(sampler, tx, p);
1184            }
1185            for (c = 0; c < 4; c++) {
1186               rgba[c][j] = lerp_2d(xw[j], yw[j],
1187                                    tx[c][0], tx[c][1], tx[c][2], tx[c][3]);
1188            }
1189         }
1190      }
1191      break;
1192   default:
1193      assert(0);
1194   }
1195}
1196
1197
1198/**
1199 * Common code for vertex/fragment program texture sampling.
1200 */
1201static INLINE void
1202sp_get_samples(struct tgsi_sampler *tgsi_sampler,
1203               const float s[QUAD_SIZE],
1204               const float t[QUAD_SIZE],
1205               const float p[QUAD_SIZE],
1206               boolean computeLambda,
1207               float lodbias,
1208               float rgba[NUM_CHANNELS][QUAD_SIZE])
1209{
1210   const struct sp_shader_sampler *samp = sp_shader_sampler(tgsi_sampler);
1211   const struct pipe_texture *texture = samp->texture;
1212   const struct pipe_sampler_state *sampler = samp->sampler;
1213
1214   if (!texture)
1215      return;
1216
1217   switch (texture->target) {
1218   case PIPE_TEXTURE_1D:
1219      assert(sampler->normalized_coords);
1220      sp_get_samples_1d(tgsi_sampler, s, t, p, computeLambda, lodbias, rgba);
1221      break;
1222   case PIPE_TEXTURE_2D:
1223      if (sampler->normalized_coords)
1224         sp_get_samples_2d(tgsi_sampler, s, t, p, computeLambda, lodbias, rgba);
1225      else
1226         sp_get_samples_rect(tgsi_sampler, s, t, p, computeLambda, lodbias, rgba);
1227      break;
1228   case PIPE_TEXTURE_3D:
1229      assert(sampler->normalized_coords);
1230      sp_get_samples_3d(tgsi_sampler, s, t, p, computeLambda, lodbias, rgba);
1231      break;
1232   case PIPE_TEXTURE_CUBE:
1233      assert(sampler->normalized_coords);
1234      sp_get_samples_cube(tgsi_sampler, s, t, p, computeLambda, lodbias, rgba);
1235      break;
1236   default:
1237      assert(0);
1238   }
1239
1240#if 0 /* DEBUG */
1241   {
1242      int i;
1243      printf("Sampled at %f, %f, %f:\n", s[0], t[0], p[0]);
1244      for (i = 0; i < 4; i++) {
1245         printf("Frag %d: %f %f %f %f\n", i,
1246                rgba[0][i],
1247                rgba[1][i],
1248                rgba[2][i],
1249                rgba[3][i]);
1250      }
1251   }
1252#endif
1253}
1254
1255
1256/**
1257 * Called via tgsi_sampler::get_samples() when running a fragment shader.
1258 * Get four filtered RGBA values from the sampler's texture.
1259 */
1260void
1261sp_get_samples_fragment(struct tgsi_sampler *tgsi_sampler,
1262                        const float s[QUAD_SIZE],
1263                        const float t[QUAD_SIZE],
1264                        const float p[QUAD_SIZE],
1265                        float lodbias,
1266                        float rgba[NUM_CHANNELS][QUAD_SIZE])
1267{
1268   sp_get_samples(tgsi_sampler, s, t, p, TRUE, lodbias, rgba);
1269}
1270
1271
1272/**
1273 * Called via tgsi_sampler::get_samples() when running a vertex shader.
1274 * Get four filtered RGBA values from the sampler's texture.
1275 */
1276void
1277sp_get_samples_vertex(struct tgsi_sampler *tgsi_sampler,
1278                      const float s[QUAD_SIZE],
1279                      const float t[QUAD_SIZE],
1280                      const float p[QUAD_SIZE],
1281                      float lodbias,
1282                      float rgba[NUM_CHANNELS][QUAD_SIZE])
1283{
1284   sp_get_samples(tgsi_sampler, s, t, p, FALSE, lodbias, rgba);
1285}
1286