s_texfetch.c revision 01e04c3f 
1/*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
5 * Copyright (c) 2009  VMware, Inc.
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 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26
27/**
28 * \file s_texfetch.c
29 *
30 * Texel fetch/store functions
31 *
32 * \author Gareth Hughes
33 */
34
35
36#include "main/errors.h"
37#include "main/macros.h"
38#include "main/texcompress.h"
39#include "main/texcompress_fxt1.h"
40#include "main/texcompress_s3tc.h"
41#include "main/texcompress_rgtc.h"
42#include "main/texcompress_etc.h"
43#include "main/teximage.h"
44#include "main/samplerobj.h"
45#include "s_context.h"
46#include "s_texfetch.h"
47#include "util/format_rgb9e5.h"
48#include "util/format_r11g11b10f.h"
49#include "util/format_srgb.h"
50
51
52/* Texel fetch routines for all supported formats
53 */
54#define DIM 1
55#include "s_texfetch_tmp.h"
56
57#define DIM 2
58#include "s_texfetch_tmp.h"
59
60#define DIM 3
61#include "s_texfetch_tmp.h"
62
63
64/**
65 * All compressed texture texel fetching is done though this function.
66 * Basically just call a core-Mesa texel fetch function.
67 */
68static void
69fetch_compressed(const struct swrast_texture_image *swImage,
70                 GLint i, GLint j, GLint k, GLfloat *texel)
71{
72   /* The FetchCompressedTexel function takes an integer pixel rowstride,
73    * while the image's rowstride is bytes per row of blocks.
74    */
75   GLuint bw, bh;
76   GLuint texelBytes = _mesa_get_format_bytes(swImage->Base.TexFormat);
77   _mesa_get_format_block_size(swImage->Base.TexFormat, &bw, &bh);
78   assert(swImage->RowStride * bw % texelBytes == 0);
79
80   swImage->FetchCompressedTexel(swImage->ImageSlices[k],
81                                 swImage->RowStride * bw / texelBytes,
82                                 i, j, texel);
83}
84
85
86
87/**
88 * Null texel fetch function.
89 *
90 * Have to have this so the FetchTexel function pointer is never NULL.
91 */
92static void fetch_null_texelf( const struct swrast_texture_image *texImage,
93                               GLint i, GLint j, GLint k, GLfloat *texel )
94{
95   (void) texImage; (void) i; (void) j; (void) k;
96   texel[RCOMP] = 0.0;
97   texel[GCOMP] = 0.0;
98   texel[BCOMP] = 0.0;
99   texel[ACOMP] = 0.0;
100   _mesa_warning(NULL, "fetch_null_texelf() called!");
101}
102
103
104#define FETCH_FUNCS(NAME)       \
105   {                            \
106      MESA_FORMAT_ ## NAME,     \
107      fetch_texel_1d_ ## NAME,  \
108      fetch_texel_2d_ ## NAME,  \
109      fetch_texel_3d_ ## NAME,  \
110   }
111
112#define FETCH_NULL(NAME)        \
113   {                            \
114      MESA_FORMAT_ ## NAME,     \
115      NULL,                     \
116      NULL,                     \
117      NULL                      \
118   }
119
120#define FETCH_COMPRESSED(NAME)  \
121   {                            \
122      MESA_FORMAT_ ## NAME,     \
123      fetch_compressed,         \
124      fetch_compressed,         \
125      fetch_compressed          \
126   }
127
128/**
129 * Table to map MESA_FORMAT_ to texel fetch/store funcs.
130 */
131static struct {
132   mesa_format Name;
133   FetchTexelFunc Fetch1D;
134   FetchTexelFunc Fetch2D;
135   FetchTexelFunc Fetch3D;
136}
137texfetch_funcs[] =
138{
139   {
140      MESA_FORMAT_NONE,
141      fetch_null_texelf,
142      fetch_null_texelf,
143      fetch_null_texelf
144   },
145
146   /* Packed unorm formats */
147   FETCH_FUNCS(A8B8G8R8_UNORM),
148   FETCH_FUNCS(X8B8G8R8_UNORM),
149   FETCH_FUNCS(R8G8B8A8_UNORM),
150   FETCH_FUNCS(R8G8B8X8_UNORM),
151   FETCH_FUNCS(B8G8R8A8_UNORM),
152   FETCH_FUNCS(B8G8R8X8_UNORM),
153   FETCH_FUNCS(A8R8G8B8_UNORM),
154   FETCH_FUNCS(X8R8G8B8_UNORM),
155   FETCH_FUNCS(L16A16_UNORM),
156   FETCH_FUNCS(A16L16_UNORM),
157   FETCH_FUNCS(B5G6R5_UNORM),
158   FETCH_FUNCS(R5G6B5_UNORM),
159   FETCH_FUNCS(B4G4R4A4_UNORM),
160   FETCH_NULL(B4G4R4X4_UNORM),
161   FETCH_FUNCS(A4R4G4B4_UNORM),
162   FETCH_FUNCS(A1B5G5R5_UNORM),
163   FETCH_NULL(X1B5G5R5_UNORM),
164   FETCH_FUNCS(B5G5R5A1_UNORM),
165   FETCH_NULL(B5G5R5X1_UNORM),
166   FETCH_FUNCS(A1R5G5B5_UNORM),
167   FETCH_FUNCS(L8A8_UNORM),
168   FETCH_FUNCS(A8L8_UNORM),
169   FETCH_FUNCS(R8G8_UNORM),
170   FETCH_FUNCS(G8R8_UNORM),
171   FETCH_FUNCS(L4A4_UNORM),
172   FETCH_FUNCS(B2G3R3_UNORM),
173   FETCH_FUNCS(R16G16_UNORM),
174   FETCH_FUNCS(G16R16_UNORM),
175   FETCH_FUNCS(B10G10R10A2_UNORM),
176   FETCH_NULL(B10G10R10X2_UNORM),
177   FETCH_FUNCS(R10G10B10A2_UNORM),
178   FETCH_NULL(R10G10B10X2_UNORM),
179
180   FETCH_FUNCS(S8_UINT_Z24_UNORM),
181   {
182      MESA_FORMAT_X8_UINT_Z24_UNORM,
183      fetch_texel_1d_S8_UINT_Z24_UNORM,
184      fetch_texel_2d_S8_UINT_Z24_UNORM,
185      fetch_texel_3d_S8_UINT_Z24_UNORM
186   },
187   FETCH_FUNCS(Z24_UNORM_S8_UINT),
188   {
189      MESA_FORMAT_Z24_UNORM_X8_UINT,
190      fetch_texel_1d_Z24_UNORM_S8_UINT,
191      fetch_texel_2d_Z24_UNORM_S8_UINT,
192      fetch_texel_3d_Z24_UNORM_S8_UINT
193   },
194   FETCH_NULL(R3G3B2_UNORM),
195   FETCH_NULL(A4B4G4R4_UNORM),
196   FETCH_NULL(R4G4B4A4_UNORM),
197   FETCH_NULL(R5G5B5A1_UNORM),
198   FETCH_NULL(A2B10G10R10_UNORM),
199   FETCH_NULL(A2R10G10B10_UNORM),
200
201   FETCH_FUNCS(YCBCR),
202   FETCH_FUNCS(YCBCR_REV),
203
204   /* Array unorm formats */
205   FETCH_FUNCS(A_UNORM8),
206   FETCH_FUNCS(A_UNORM16),
207   FETCH_FUNCS(L_UNORM8),
208   FETCH_FUNCS(L_UNORM16),
209   FETCH_FUNCS(I_UNORM8),
210   FETCH_FUNCS(I_UNORM16),
211   FETCH_FUNCS(R_UNORM8),
212   FETCH_FUNCS(R_UNORM16),
213   FETCH_FUNCS(BGR_UNORM8),
214   FETCH_FUNCS(RGB_UNORM8),
215   FETCH_FUNCS(RGBA_UNORM16),
216   FETCH_FUNCS(RGBX_UNORM16),
217   FETCH_FUNCS(Z_UNORM16),
218   FETCH_FUNCS(Z_UNORM32),
219   FETCH_NULL(S_UINT8),
220
221   /* Packed signed/normalized formats */
222   FETCH_FUNCS(A8B8G8R8_SNORM),
223   FETCH_FUNCS(X8B8G8R8_SNORM),
224   FETCH_FUNCS(R8G8B8A8_SNORM),
225   FETCH_NULL(R8G8B8X8_SNORM),
226   FETCH_FUNCS(R16G16_SNORM),
227   FETCH_NULL(G16R16_SNORM),
228   FETCH_FUNCS(R8G8_SNORM),
229   FETCH_NULL(G8R8_SNORM),
230   FETCH_FUNCS(L8A8_SNORM),
231   FETCH_FUNCS(A8L8_SNORM),
232
233   /* Array signed/normalized formats */
234   FETCH_FUNCS(A_SNORM8),
235   FETCH_FUNCS(A_SNORM16),
236   FETCH_FUNCS(L_SNORM8),
237   FETCH_FUNCS(L_SNORM16),
238   FETCH_FUNCS(I_SNORM8),
239   FETCH_FUNCS(I_SNORM16),
240   FETCH_FUNCS(R_SNORM8),
241   FETCH_FUNCS(R_SNORM16),
242   FETCH_FUNCS(LA_SNORM16),
243   FETCH_FUNCS(RGB_SNORM16),
244   FETCH_FUNCS(RGBA_SNORM16),
245   FETCH_NULL(RGBX_SNORM16),
246
247   /* Packed sRGB formats */
248   FETCH_FUNCS(A8B8G8R8_SRGB),
249   FETCH_FUNCS(B8G8R8A8_SRGB),
250   FETCH_FUNCS(A8R8G8B8_SRGB),
251   FETCH_NULL(B8G8R8X8_SRGB),
252   FETCH_NULL(X8R8G8B8_SRGB),
253   FETCH_FUNCS(R8G8B8A8_SRGB),
254   FETCH_FUNCS(R8G8B8X8_SRGB),
255   FETCH_FUNCS(X8B8G8R8_SRGB),
256   FETCH_FUNCS(L8A8_SRGB),
257   FETCH_FUNCS(A8L8_SRGB),
258
259   /* Array sRGB formats */
260   FETCH_FUNCS(L_SRGB8),
261   FETCH_FUNCS(BGR_SRGB8),
262
263   /* Packed float formats */
264   FETCH_FUNCS(R9G9B9E5_FLOAT),
265   FETCH_FUNCS(R11G11B10_FLOAT),
266   FETCH_FUNCS(Z32_FLOAT_S8X24_UINT),
267
268   /* Array float formats */
269   FETCH_FUNCS(A_FLOAT16),
270   FETCH_FUNCS(A_FLOAT32),
271   FETCH_FUNCS(L_FLOAT16),
272   FETCH_FUNCS(L_FLOAT32),
273   FETCH_FUNCS(LA_FLOAT16),
274   FETCH_FUNCS(LA_FLOAT32),
275   FETCH_FUNCS(I_FLOAT16),
276   FETCH_FUNCS(I_FLOAT32),
277   FETCH_FUNCS(R_FLOAT16),
278   FETCH_FUNCS(R_FLOAT32),
279   FETCH_FUNCS(RG_FLOAT16),
280   FETCH_FUNCS(RG_FLOAT32),
281   FETCH_FUNCS(RGB_FLOAT16),
282   FETCH_FUNCS(RGB_FLOAT32),
283   FETCH_FUNCS(RGBA_FLOAT16),
284   FETCH_FUNCS(RGBA_FLOAT32),
285   FETCH_FUNCS(RGBX_FLOAT16),
286   FETCH_FUNCS(RGBX_FLOAT32),
287   {
288      MESA_FORMAT_Z_FLOAT32,
289      fetch_texel_1d_R_FLOAT32, /* Reuse the R32F functions. */
290      fetch_texel_2d_R_FLOAT32,
291      fetch_texel_3d_R_FLOAT32
292   },
293
294   /* Packed signed/unsigned non-normalized integer formats */
295   FETCH_NULL(A8B8G8R8_UINT),
296   FETCH_NULL(A8R8G8B8_UINT),
297   FETCH_NULL(R8G8B8A8_UINT),
298   FETCH_NULL(B8G8R8A8_UINT),
299   FETCH_NULL(B10G10R10A2_UINT),
300   FETCH_NULL(R10G10B10A2_UINT),
301   FETCH_NULL(A2B10G10R10_UINT),
302   FETCH_NULL(A2R10G10B10_UINT),
303   FETCH_NULL(B5G6R5_UINT),
304   FETCH_NULL(R5G6B5_UINT),
305   FETCH_NULL(B2G3R3_UINT),
306   FETCH_NULL(R3G3B2_UINT),
307   FETCH_NULL(A4B4G4R4_UINT),
308   FETCH_NULL(R4G4B4A4_UINT),
309   FETCH_NULL(B4G4R4A4_UINT),
310   FETCH_NULL(A4R4G4B4_UINT),
311   FETCH_NULL(A1B5G5R5_UINT),
312   FETCH_NULL(B5G5R5A1_UINT),
313   FETCH_NULL(A1R5G5B5_UINT),
314   FETCH_NULL(R5G5B5A1_UINT),
315
316   /* Array signed/unsigned non-normalized integer formats */
317   FETCH_NULL(A_UINT8),
318   FETCH_NULL(A_UINT16),
319   FETCH_NULL(A_UINT32),
320   FETCH_NULL(A_SINT8),
321   FETCH_NULL(A_SINT16),
322   FETCH_NULL(A_SINT32),
323   FETCH_NULL(I_UINT8),
324   FETCH_NULL(I_UINT16),
325   FETCH_NULL(I_UINT32),
326   FETCH_NULL(I_SINT8),
327   FETCH_NULL(I_SINT16),
328   FETCH_NULL(I_SINT32),
329   FETCH_NULL(L_UINT8),
330   FETCH_NULL(L_UINT16),
331   FETCH_NULL(L_UINT32),
332   FETCH_NULL(L_SINT8),
333   FETCH_NULL(L_SINT16),
334   FETCH_NULL(L_SINT32),
335   FETCH_NULL(LA_UINT8),
336   FETCH_NULL(LA_UINT16),
337   FETCH_NULL(LA_UINT32),
338   FETCH_NULL(LA_SINT8),
339   FETCH_NULL(LA_SINT16),
340   FETCH_NULL(LA_SINT32),
341   FETCH_NULL(R_UINT8),
342   FETCH_NULL(R_UINT16),
343   FETCH_NULL(R_UINT32),
344   FETCH_NULL(R_SINT8),
345   FETCH_NULL(R_SINT16),
346   FETCH_NULL(R_SINT32),
347   FETCH_NULL(RG_UINT8),
348   FETCH_NULL(RG_UINT16),
349   FETCH_NULL(RG_UINT32),
350   FETCH_NULL(RG_SINT8),
351   FETCH_NULL(RG_SINT16),
352   FETCH_NULL(RG_SINT32),
353   FETCH_NULL(RGB_UINT8),
354   FETCH_NULL(RGB_UINT16),
355   FETCH_NULL(RGB_UINT32),
356   FETCH_NULL(RGB_SINT8),
357   FETCH_NULL(RGB_SINT16),
358   FETCH_NULL(RGB_SINT32),
359   FETCH_FUNCS(RGBA_UINT8),
360   FETCH_FUNCS(RGBA_UINT16),
361   FETCH_FUNCS(RGBA_UINT32),
362   FETCH_FUNCS(RGBA_SINT8),
363   FETCH_FUNCS(RGBA_SINT16),
364   FETCH_FUNCS(RGBA_SINT32),
365   FETCH_NULL(RGBX_UINT8),
366   FETCH_NULL(RGBX_UINT16),
367   FETCH_NULL(RGBX_UINT32),
368   FETCH_NULL(RGBX_SINT8),
369   FETCH_NULL(RGBX_SINT16),
370   FETCH_NULL(RGBX_SINT32),
371
372   /* DXT compressed formats */
373   FETCH_COMPRESSED(RGB_DXT1),
374   FETCH_COMPRESSED(RGBA_DXT1),
375   FETCH_COMPRESSED(RGBA_DXT3),
376   FETCH_COMPRESSED(RGBA_DXT5),
377
378   /* DXT sRGB compressed formats */
379   FETCH_COMPRESSED(SRGB_DXT1),
380   FETCH_COMPRESSED(SRGBA_DXT1),
381   FETCH_COMPRESSED(SRGBA_DXT3),
382   FETCH_COMPRESSED(SRGBA_DXT5),
383
384   /* FXT1 compressed formats */
385   FETCH_COMPRESSED(RGB_FXT1),
386   FETCH_COMPRESSED(RGBA_FXT1),
387
388   /* RGTC compressed formats */
389   FETCH_COMPRESSED(R_RGTC1_UNORM),
390   FETCH_COMPRESSED(R_RGTC1_SNORM),
391   FETCH_COMPRESSED(RG_RGTC2_UNORM),
392   FETCH_COMPRESSED(RG_RGTC2_SNORM),
393
394   /* LATC1/2 compressed formats */
395   FETCH_COMPRESSED(L_LATC1_UNORM),
396   FETCH_COMPRESSED(L_LATC1_SNORM),
397   FETCH_COMPRESSED(LA_LATC2_UNORM),
398   FETCH_COMPRESSED(LA_LATC2_SNORM),
399
400   /* ETC1/2 compressed formats */
401   FETCH_COMPRESSED(ETC1_RGB8),
402   FETCH_COMPRESSED(ETC2_RGB8),
403   FETCH_COMPRESSED(ETC2_SRGB8),
404   FETCH_COMPRESSED(ETC2_RGBA8_EAC),
405   FETCH_COMPRESSED(ETC2_SRGB8_ALPHA8_EAC),
406   FETCH_COMPRESSED(ETC2_R11_EAC),
407   FETCH_COMPRESSED(ETC2_RG11_EAC),
408   FETCH_COMPRESSED(ETC2_SIGNED_R11_EAC),
409   FETCH_COMPRESSED(ETC2_SIGNED_RG11_EAC),
410   FETCH_COMPRESSED(ETC2_RGB8_PUNCHTHROUGH_ALPHA1),
411   FETCH_COMPRESSED(ETC2_SRGB8_PUNCHTHROUGH_ALPHA1),
412   FETCH_COMPRESSED(BPTC_RGBA_UNORM),
413   FETCH_COMPRESSED(BPTC_SRGB_ALPHA_UNORM),
414   FETCH_COMPRESSED(BPTC_RGB_SIGNED_FLOAT),
415   FETCH_COMPRESSED(BPTC_RGB_UNSIGNED_FLOAT),
416
417   /* ASTC compressed formats */
418   FETCH_NULL(RGBA_ASTC_4x4),
419   FETCH_NULL(RGBA_ASTC_5x4),
420   FETCH_NULL(RGBA_ASTC_5x5),
421   FETCH_NULL(RGBA_ASTC_6x5),
422   FETCH_NULL(RGBA_ASTC_6x6),
423   FETCH_NULL(RGBA_ASTC_8x5),
424   FETCH_NULL(RGBA_ASTC_8x6),
425   FETCH_NULL(RGBA_ASTC_8x8),
426   FETCH_NULL(RGBA_ASTC_10x5),
427   FETCH_NULL(RGBA_ASTC_10x6),
428   FETCH_NULL(RGBA_ASTC_10x8),
429   FETCH_NULL(RGBA_ASTC_10x10),
430   FETCH_NULL(RGBA_ASTC_12x10),
431   FETCH_NULL(RGBA_ASTC_12x12),
432   FETCH_NULL(SRGB8_ALPHA8_ASTC_4x4),
433   FETCH_NULL(SRGB8_ALPHA8_ASTC_5x4),
434   FETCH_NULL(SRGB8_ALPHA8_ASTC_5x5),
435   FETCH_NULL(SRGB8_ALPHA8_ASTC_6x5),
436   FETCH_NULL(SRGB8_ALPHA8_ASTC_6x6),
437   FETCH_NULL(SRGB8_ALPHA8_ASTC_8x5),
438   FETCH_NULL(SRGB8_ALPHA8_ASTC_8x6),
439   FETCH_NULL(SRGB8_ALPHA8_ASTC_8x8),
440   FETCH_NULL(SRGB8_ALPHA8_ASTC_10x5),
441   FETCH_NULL(SRGB8_ALPHA8_ASTC_10x6),
442   FETCH_NULL(SRGB8_ALPHA8_ASTC_10x8),
443   FETCH_NULL(SRGB8_ALPHA8_ASTC_10x10),
444   FETCH_NULL(SRGB8_ALPHA8_ASTC_12x10),
445   FETCH_NULL(SRGB8_ALPHA8_ASTC_12x12),
446
447   FETCH_NULL(RGBA_ASTC_3x3x3),
448   FETCH_NULL(RGBA_ASTC_4x3x3),
449   FETCH_NULL(RGBA_ASTC_4x4x3),
450   FETCH_NULL(RGBA_ASTC_4x4x4),
451   FETCH_NULL(RGBA_ASTC_5x4x4),
452   FETCH_NULL(RGBA_ASTC_5x5x4),
453   FETCH_NULL(RGBA_ASTC_5x5x5),
454   FETCH_NULL(RGBA_ASTC_6x5x5),
455   FETCH_NULL(RGBA_ASTC_6x6x5),
456   FETCH_NULL(RGBA_ASTC_6x6x6),
457   FETCH_NULL(SRGB8_ALPHA8_ASTC_3x3x3),
458   FETCH_NULL(SRGB8_ALPHA8_ASTC_4x3x3),
459   FETCH_NULL(SRGB8_ALPHA8_ASTC_4x4x3),
460   FETCH_NULL(SRGB8_ALPHA8_ASTC_4x4x4),
461   FETCH_NULL(SRGB8_ALPHA8_ASTC_5x4x4),
462   FETCH_NULL(SRGB8_ALPHA8_ASTC_5x5x4),
463   FETCH_NULL(SRGB8_ALPHA8_ASTC_5x5x5),
464   FETCH_NULL(SRGB8_ALPHA8_ASTC_6x5x5),
465   FETCH_NULL(SRGB8_ALPHA8_ASTC_6x6x5),
466   FETCH_NULL(SRGB8_ALPHA8_ASTC_6x6x6)
467};
468
469
470/**
471 * Initialize the texture image's FetchTexel methods.
472 */
473static void
474set_fetch_functions(const struct gl_sampler_object *samp,
475                    struct swrast_texture_image *texImage, GLuint dims)
476{
477   mesa_format format = texImage->Base.TexFormat;
478
479#ifdef DEBUG
480   /* check that the table entries are sorted by format name */
481   mesa_format fmt;
482   for (fmt = 0; fmt < MESA_FORMAT_COUNT; fmt++) {
483      assert(texfetch_funcs[fmt].Name == fmt);
484   }
485#endif
486
487   STATIC_ASSERT(ARRAY_SIZE(texfetch_funcs) == MESA_FORMAT_COUNT);
488
489   if (samp->sRGBDecode == GL_SKIP_DECODE_EXT &&
490       _mesa_get_format_color_encoding(format) == GL_SRGB) {
491      format = _mesa_get_srgb_format_linear(format);
492   }
493
494   assert(format < MESA_FORMAT_COUNT);
495
496   switch (dims) {
497   case 1:
498      texImage->FetchTexel = texfetch_funcs[format].Fetch1D;
499      break;
500   case 2:
501      texImage->FetchTexel = texfetch_funcs[format].Fetch2D;
502      break;
503   case 3:
504      texImage->FetchTexel = texfetch_funcs[format].Fetch3D;
505      break;
506   default:
507      assert(!"Bad dims in set_fetch_functions()");
508   }
509
510   texImage->FetchCompressedTexel = _mesa_get_compressed_fetch_func(format);
511
512   assert(texImage->FetchTexel);
513}
514
515void
516_mesa_update_fetch_functions(struct gl_context *ctx, GLuint unit)
517{
518   struct gl_texture_object *texObj = ctx->Texture.Unit[unit]._Current;
519   struct gl_sampler_object *samp;
520   GLuint face, i;
521   GLuint dims;
522
523   if (!texObj)
524      return;
525
526   samp = _mesa_get_samplerobj(ctx, unit);
527
528   dims = _mesa_get_texture_dimensions(texObj->Target);
529
530   for (face = 0; face < 6; face++) {
531      for (i = 0; i < MAX_TEXTURE_LEVELS; i++) {
532         if (texObj->Image[face][i]) {
533	    set_fetch_functions(samp,
534                                swrast_texture_image(texObj->Image[face][i]),
535                                dims);
536         }
537      }
538   }
539}
540