2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
6 * Copyright (c) 2008 VMware, Inc.
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the "Software"),
10 * to deal in the Software without restriction, including without limitation
11 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
12 * and/or sell copies of the Software, and to permit persons to whom the
13 * Software is furnished to do so, subject to the following conditions:
15 * The above copyright notice and this permission notice shall be included
16 * in all copies or substantial portions of the Software.
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
22 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
23 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24 * OTHER DEALINGS IN THE SOFTWARE.
30 * Helper functions for texture compression.
41 #include "texcompress.h"
42 #include "texcompress_fxt1.h"
43 #include "texcompress_rgtc.h"
44 #include "texcompress_s3tc.h"
45 #include "texcompress_etc.h"
49 * Get the GL base format of a specified GL compressed texture format
51 * From page 232 of the OpenGL 3.3 (Compatiblity Profile) spec:
53 * "Compressed Internal Format Base Internal Format Type
54 * --------------------------- -------------------- ---------
55 * COMPRESSED_ALPHA ALPHA Generic
56 * COMPRESSED_LUMINANCE LUMINANCE Generic
57 * COMPRESSED_LUMINANCE_ALPHA LUMINANCE_ALPHA Generic
58 * COMPRESSED_INTENSITY INTENSITY Generic
59 * COMPRESSED_RED RED Generic
60 * COMPRESSED_RG RG Generic
61 * COMPRESSED_RGB RGB Generic
62 * COMPRESSED_RGBA RGBA Generic
63 * COMPRESSED_SRGB RGB Generic
64 * COMPRESSED_SRGB_ALPHA RGBA Generic
65 * COMPRESSED_SLUMINANCE LUMINANCE Generic
66 * COMPRESSED_SLUMINANCE_ALPHA LUMINANCE_ALPHA Generic
67 * COMPRESSED_RED_RGTC1 RED Specific
68 * COMPRESSED_SIGNED_RED_RGTC1 RED Specific
69 * COMPRESSED_RG_RGTC2 RG Specific
70 * COMPRESSED_SIGNED_RG_RGTC2 RG Specific"
73 * The base format of \c format if \c format is a compressed format (either
74 * generic or specific. Otherwise 0 is returned.
77 _mesa_gl_compressed_format_base_format(GLenum format
)
80 case GL_COMPRESSED_RED
:
81 case GL_COMPRESSED_R11_EAC
:
82 case GL_COMPRESSED_RED_RGTC1
:
83 case GL_COMPRESSED_SIGNED_R11_EAC
:
84 case GL_COMPRESSED_SIGNED_RED_RGTC1
:
87 case GL_COMPRESSED_RG
:
88 case GL_COMPRESSED_RG11_EAC
:
89 case GL_COMPRESSED_RG_RGTC2
:
90 case GL_COMPRESSED_SIGNED_RG11_EAC
:
91 case GL_COMPRESSED_SIGNED_RG_RGTC2
:
94 case GL_COMPRESSED_RGB
:
95 case GL_COMPRESSED_SRGB
:
96 case GL_COMPRESSED_RGB_S3TC_DXT1_EXT
:
97 case GL_COMPRESSED_RGB_FXT1_3DFX
:
98 case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT
:
99 case GL_ETC1_RGB8_OES
:
100 case GL_COMPRESSED_RGB8_ETC2
:
101 case GL_COMPRESSED_SRGB8_ETC2
:
104 case GL_COMPRESSED_RGBA
:
105 case GL_COMPRESSED_SRGB_ALPHA
:
106 case GL_COMPRESSED_RGBA_BPTC_UNORM_ARB
:
107 case GL_COMPRESSED_SRGB_ALPHA_BPTC_UNORM_ARB
:
108 case GL_COMPRESSED_RGB_BPTC_SIGNED_FLOAT_ARB
:
109 case GL_COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_ARB
:
110 case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT
:
111 case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT
:
112 case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT
:
113 case GL_COMPRESSED_RGBA_FXT1_3DFX
:
114 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT
:
115 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT
:
116 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT
:
117 case GL_COMPRESSED_RGBA8_ETC2_EAC
:
118 case GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC
:
119 case GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2
:
120 case GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2
:
123 case GL_COMPRESSED_ALPHA
:
126 case GL_COMPRESSED_LUMINANCE
:
127 case GL_COMPRESSED_SLUMINANCE
:
128 case GL_COMPRESSED_LUMINANCE_LATC1_EXT
:
129 case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT
:
132 case GL_COMPRESSED_LUMINANCE_ALPHA
:
133 case GL_COMPRESSED_SLUMINANCE_ALPHA
:
134 case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT
:
135 case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT
:
136 case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI
:
137 return GL_LUMINANCE_ALPHA
;
139 case GL_COMPRESSED_INTENSITY
:
148 * Return list of (and count of) all specific texture compression
149 * formats that are supported.
151 * Some formats are \b not returned by this function. The
152 * \c GL_COMPRESSED_TEXTURE_FORMATS query only returns formats that are
153 * "suitable for general-purpose usage." All texture compression extensions
154 * have taken this to mean either linear RGB or linear RGBA.
156 * The GL_ARB_texture_compress_rgtc spec says:
158 * "19) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and
159 * GL_COMPRESSED_TEXTURE_FORMATS queries return the RGTC formats?
163 * The OpenGL 2.1 specification says "The only values returned
164 * by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those
165 * corresponding to formats suitable for general-purpose usage.
166 * The renderer will not enumerate formats with restrictions that
167 * need to be specifically understood prior to use."
169 * Compressed textures with just red or red-green components are
170 * not general-purpose so should not be returned by these queries
171 * because they have restrictions.
173 * Applications that seek to use the RGTC formats should do so
174 * by looking for this extension's name in the string returned by
175 * glGetString(GL_EXTENSIONS) rather than
176 * what GL_NUM_COMPRESSED_TEXTURE_FORMATS and
177 * GL_COMPRESSED_TEXTURE_FORMATS return."
179 * There is nearly identical wording in the GL_EXT_texture_compression_rgtc
182 * The GL_EXT_texture_rRGB spec says:
184 * "22) Should the new COMPRESSED_SRGB_* formats be listed in an
185 * implementation's GL_COMPRESSED_TEXTURE_FORMATS list?
187 * RESOLVED: No. Section 3.8.1 says formats listed by
188 * GL_COMPRESSED_TEXTURE_FORMATS are "suitable for general-purpose
189 * usage." The non-linear distribution of red, green, and
190 * blue for these sRGB compressed formats makes them not really
193 * The GL_EXT_texture_compression_latc spec says:
195 * "16) Should the GL_NUM_COMPRESSED_TEXTURE_FORMATS and
196 * GL_COMPRESSED_TEXTURE_FORMATS queries return the LATC formats?
200 * The OpenGL 2.1 specification says "The only values returned
201 * by this query [GL_COMPRESSED_TEXTURE_FORMATS"] are those
202 * corresponding to formats suitable for general-purpose usage.
203 * The renderer will not enumerate formats with restrictions that
204 * need to be specifically understood prior to use."
206 * Historically, OpenGL implementation have advertised the RGB and
207 * RGBA versions of the S3TC extensions compressed format tokens
208 * through this mechanism.
210 * The specification is not sufficiently clear about what "suitable
211 * for general-purpose usage" means. Historically that seems to mean
212 * unsigned RGB or unsigned RGBA. The DXT1 format supporting alpha
213 * (GL_COMPRESSED_RGBA_S3TC_DXT1_EXT) is not exposed in the list (at
214 * least for NVIDIA drivers) because the alpha is always 1.0 expect
215 * when it is 0.0 when RGB is required to be black. NVIDIA's even
216 * limits itself to true linear RGB or RGBA formats, specifically
217 * not including EXT_texture_sRGB's sRGB S3TC compressed formats.
219 * Adding luminance and luminance-alpha texture formats (and
220 * certainly signed versions of luminance and luminance-alpha
221 * formats!) invites potential comptaibility problems with old
222 * applications using this mechanism since old applications are
223 * unlikely to expect non-RGB or non-RGBA formats to be advertised
224 * through this mechanism. However no specific misinteractions
225 * with old applications is known.
227 * Applications that seek to use the LATC formats should do so
228 * by looking for this extension's name in the string returned by
229 * glGetString(GL_EXTENSIONS) rather than
230 * what GL_NUM_COMPRESSED_TEXTURE_FORMATS and
231 * GL_COMPRESSED_TEXTURE_FORMATS return."
233 * There is no formal spec for GL_ATI_texture_compression_3dc. Since the
234 * formats added by this extension are luminance-alpha formats, it is
235 * reasonable to expect them to follow the same rules as
236 * GL_EXT_texture_compression_latc. At the very least, Catalyst 11.6 does not
237 * expose the 3dc formats through this mechanism.
239 * \param ctx the GL context
240 * \param formats the resulting format list (may be NULL).
242 * \return number of formats.
245 _mesa_get_compressed_formats(struct gl_context
*ctx
, GLint
*formats
)
248 if (ctx
->Extensions
.TDFX_texture_compression_FXT1
) {
250 formats
[n
++] = GL_COMPRESSED_RGB_FXT1_3DFX
;
251 formats
[n
++] = GL_COMPRESSED_RGBA_FXT1_3DFX
;
258 if (ctx
->Extensions
.EXT_texture_compression_s3tc
) {
260 formats
[n
++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT
;
261 formats
[n
++] = GL_COMPRESSED_RGBA_S3TC_DXT3_EXT
;
262 formats
[n
++] = GL_COMPRESSED_RGBA_S3TC_DXT5_EXT
;
268 if (_mesa_is_desktop_gl(ctx
)
269 && ctx
->Extensions
.ANGLE_texture_compression_dxt
) {
271 formats
[n
++] = GL_RGB_S3TC
;
272 formats
[n
++] = GL_RGB4_S3TC
;
273 formats
[n
++] = GL_RGBA_S3TC
;
274 formats
[n
++] = GL_RGBA4_S3TC
;
281 if (ctx
->Extensions
.OES_compressed_ETC1_RGB8_texture
) {
283 formats
[n
++] = GL_ETC1_RGB8_OES
;
290 if (ctx
->API
== API_OPENGLES
) {
292 formats
[n
++] = GL_PALETTE4_RGB8_OES
;
293 formats
[n
++] = GL_PALETTE4_RGBA8_OES
;
294 formats
[n
++] = GL_PALETTE4_R5_G6_B5_OES
;
295 formats
[n
++] = GL_PALETTE4_RGBA4_OES
;
296 formats
[n
++] = GL_PALETTE4_RGB5_A1_OES
;
297 formats
[n
++] = GL_PALETTE8_RGB8_OES
;
298 formats
[n
++] = GL_PALETTE8_RGBA8_OES
;
299 formats
[n
++] = GL_PALETTE8_R5_G6_B5_OES
;
300 formats
[n
++] = GL_PALETTE8_RGBA4_OES
;
301 formats
[n
++] = GL_PALETTE8_RGB5_A1_OES
;
308 if (_mesa_is_gles3(ctx
)) {
310 formats
[n
++] = GL_COMPRESSED_RGB8_ETC2
;
311 formats
[n
++] = GL_COMPRESSED_SRGB8_ETC2
;
312 formats
[n
++] = GL_COMPRESSED_RGBA8_ETC2_EAC
;
313 formats
[n
++] = GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC
;
314 formats
[n
++] = GL_COMPRESSED_R11_EAC
;
315 formats
[n
++] = GL_COMPRESSED_RG11_EAC
;
316 formats
[n
++] = GL_COMPRESSED_SIGNED_R11_EAC
;
317 formats
[n
++] = GL_COMPRESSED_SIGNED_RG11_EAC
;
318 formats
[n
++] = GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2
;
319 formats
[n
++] = GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2
;
330 * Convert a compressed MESA_FORMAT_x to a GLenum.
333 _mesa_glenum_to_compressed_format(GLenum format
)
336 case GL_COMPRESSED_RGB_FXT1_3DFX
:
337 return MESA_FORMAT_RGB_FXT1
;
338 case GL_COMPRESSED_RGBA_FXT1_3DFX
:
339 return MESA_FORMAT_RGBA_FXT1
;
341 case GL_COMPRESSED_RGB_S3TC_DXT1_EXT
:
343 return MESA_FORMAT_RGB_DXT1
;
344 case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT
:
346 return MESA_FORMAT_RGBA_DXT1
;
347 case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT
:
349 return MESA_FORMAT_RGBA_DXT3
;
350 case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT
:
352 return MESA_FORMAT_RGBA_DXT5
;
354 case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT
:
355 return MESA_FORMAT_SRGB_DXT1
;
356 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT
:
357 return MESA_FORMAT_SRGBA_DXT1
;
358 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT
:
359 return MESA_FORMAT_SRGBA_DXT3
;
360 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT
:
361 return MESA_FORMAT_SRGBA_DXT5
;
363 case GL_COMPRESSED_RED_RGTC1
:
364 return MESA_FORMAT_RED_RGTC1
;
365 case GL_COMPRESSED_SIGNED_RED_RGTC1
:
366 return MESA_FORMAT_SIGNED_RED_RGTC1
;
367 case GL_COMPRESSED_RG_RGTC2
:
368 return MESA_FORMAT_RG_RGTC2
;
369 case GL_COMPRESSED_SIGNED_RG_RGTC2
:
370 return MESA_FORMAT_SIGNED_RG_RGTC2
;
372 case GL_COMPRESSED_LUMINANCE_LATC1_EXT
:
373 return MESA_FORMAT_L_LATC1
;
374 case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT
:
375 return MESA_FORMAT_SIGNED_L_LATC1
;
376 case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT
:
377 case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI
:
378 return MESA_FORMAT_LA_LATC2
;
379 case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT
:
380 return MESA_FORMAT_SIGNED_LA_LATC2
;
382 case GL_ETC1_RGB8_OES
:
383 return MESA_FORMAT_ETC1_RGB8
;
384 case GL_COMPRESSED_RGB8_ETC2
:
385 return MESA_FORMAT_ETC2_RGB8
;
386 case GL_COMPRESSED_SRGB8_ETC2
:
387 return MESA_FORMAT_ETC2_SRGB8
;
388 case GL_COMPRESSED_RGBA8_ETC2_EAC
:
389 return MESA_FORMAT_ETC2_RGBA8_EAC
;
390 case GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC
:
391 return MESA_FORMAT_ETC2_SRGB8_ALPHA8_EAC
;
392 case GL_COMPRESSED_R11_EAC
:
393 return MESA_FORMAT_ETC2_R11_EAC
;
394 case GL_COMPRESSED_RG11_EAC
:
395 return MESA_FORMAT_ETC2_RG11_EAC
;
396 case GL_COMPRESSED_SIGNED_R11_EAC
:
397 return MESA_FORMAT_ETC2_SIGNED_R11_EAC
;
398 case GL_COMPRESSED_SIGNED_RG11_EAC
:
399 return MESA_FORMAT_ETC2_SIGNED_RG11_EAC
;
400 case GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2
:
401 return MESA_FORMAT_ETC2_RGB8_PUNCHTHROUGH_ALPHA1
;
402 case GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2
:
403 return MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1
;
406 return MESA_FORMAT_NONE
;
412 * Given a compressed MESA_FORMAT_x value, return the corresponding
413 * GLenum for that format.
414 * This is needed for glGetTexLevelParameter(GL_TEXTURE_INTERNAL_FORMAT)
415 * which must return the specific texture format used when the user might
416 * have originally specified a generic compressed format in their
417 * glTexImage2D() call.
418 * For non-compressed textures, we always return the user-specified
419 * internal format unchanged.
422 _mesa_compressed_format_to_glenum(struct gl_context
*ctx
, gl_format mesaFormat
)
424 switch (mesaFormat
) {
425 case MESA_FORMAT_RGB_FXT1
:
426 return GL_COMPRESSED_RGB_FXT1_3DFX
;
427 case MESA_FORMAT_RGBA_FXT1
:
428 return GL_COMPRESSED_RGBA_FXT1_3DFX
;
429 case MESA_FORMAT_RGB_DXT1
:
430 return GL_COMPRESSED_RGB_S3TC_DXT1_EXT
;
431 case MESA_FORMAT_RGBA_DXT1
:
432 return GL_COMPRESSED_RGBA_S3TC_DXT1_EXT
;
433 case MESA_FORMAT_RGBA_DXT3
:
434 return GL_COMPRESSED_RGBA_S3TC_DXT3_EXT
;
435 case MESA_FORMAT_RGBA_DXT5
:
436 return GL_COMPRESSED_RGBA_S3TC_DXT5_EXT
;
437 case MESA_FORMAT_SRGB_DXT1
:
438 return GL_COMPRESSED_SRGB_S3TC_DXT1_EXT
;
439 case MESA_FORMAT_SRGBA_DXT1
:
440 return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT
;
441 case MESA_FORMAT_SRGBA_DXT3
:
442 return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT
;
443 case MESA_FORMAT_SRGBA_DXT5
:
444 return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT
;
445 case MESA_FORMAT_RED_RGTC1
:
446 return GL_COMPRESSED_RED_RGTC1
;
447 case MESA_FORMAT_SIGNED_RED_RGTC1
:
448 return GL_COMPRESSED_SIGNED_RED_RGTC1
;
449 case MESA_FORMAT_RG_RGTC2
:
450 return GL_COMPRESSED_RG_RGTC2
;
451 case MESA_FORMAT_SIGNED_RG_RGTC2
:
452 return GL_COMPRESSED_SIGNED_RG_RGTC2
;
454 case MESA_FORMAT_L_LATC1
:
455 return GL_COMPRESSED_LUMINANCE_LATC1_EXT
;
456 case MESA_FORMAT_SIGNED_L_LATC1
:
457 return GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT
;
458 case MESA_FORMAT_LA_LATC2
:
459 return GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT
;
460 case MESA_FORMAT_SIGNED_LA_LATC2
:
461 return GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT
;
463 case MESA_FORMAT_ETC1_RGB8
:
464 return GL_ETC1_RGB8_OES
;
465 case MESA_FORMAT_ETC2_RGB8
:
466 return GL_COMPRESSED_RGB8_ETC2
;
467 case MESA_FORMAT_ETC2_SRGB8
:
468 return GL_COMPRESSED_SRGB8_ETC2
;
469 case MESA_FORMAT_ETC2_RGBA8_EAC
:
470 return GL_COMPRESSED_RGBA8_ETC2_EAC
;
471 case MESA_FORMAT_ETC2_SRGB8_ALPHA8_EAC
:
472 return GL_COMPRESSED_SRGB8_ALPHA8_ETC2_EAC
;
473 case MESA_FORMAT_ETC2_R11_EAC
:
474 return GL_COMPRESSED_R11_EAC
;
475 case MESA_FORMAT_ETC2_RG11_EAC
:
476 return GL_COMPRESSED_RG11_EAC
;
477 case MESA_FORMAT_ETC2_SIGNED_R11_EAC
:
478 return GL_COMPRESSED_SIGNED_R11_EAC
;
479 case MESA_FORMAT_ETC2_SIGNED_RG11_EAC
:
480 return GL_COMPRESSED_SIGNED_RG11_EAC
;
481 case MESA_FORMAT_ETC2_RGB8_PUNCHTHROUGH_ALPHA1
:
482 return GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2
;
483 case MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1
:
484 return GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2
;
487 _mesa_problem(ctx
, "Unexpected mesa texture format in"
488 " _mesa_compressed_format_to_glenum()");
495 * Return the address of the pixel at (col, row, img) in a
496 * compressed texture image.
497 * \param col, row, img - image position (3D), should be a multiple of the
498 * format's block size.
499 * \param format - compressed image format
500 * \param width - image width (stride) in pixels
501 * \param image - the image address
502 * \return address of pixel at (row, col, img)
505 _mesa_compressed_image_address(GLint col
, GLint row
, GLint img
,
506 gl_format mesaFormat
,
507 GLsizei width
, const GLubyte
*image
)
509 /* XXX only 2D images implemented, not 3D */
510 const GLuint blockSize
= _mesa_get_format_bytes(mesaFormat
);
514 _mesa_get_format_block_size(mesaFormat
, &bw
, &bh
);
516 ASSERT(col
% bw
== 0);
517 ASSERT(row
% bh
== 0);
519 offset
= ((width
+ bw
- 1) / bw
) * (row
/ bh
) + col
/ bw
;
522 return (GLubyte
*) image
+ offset
;
527 * Return a texel-fetch function for the given format, or NULL if
530 compressed_fetch_func
531 _mesa_get_compressed_fetch_func(gl_format format
)
534 case MESA_FORMAT_RGB_DXT1
:
535 case MESA_FORMAT_RGBA_DXT1
:
536 case MESA_FORMAT_RGBA_DXT3
:
537 case MESA_FORMAT_RGBA_DXT5
:
538 case MESA_FORMAT_SRGB_DXT1
:
539 case MESA_FORMAT_SRGBA_DXT1
:
540 case MESA_FORMAT_SRGBA_DXT3
:
541 case MESA_FORMAT_SRGBA_DXT5
:
542 return _mesa_get_dxt_fetch_func(format
);
543 case MESA_FORMAT_RGB_FXT1
:
544 case MESA_FORMAT_RGBA_FXT1
:
545 return _mesa_get_fxt_fetch_func(format
);
546 case MESA_FORMAT_RED_RGTC1
:
547 case MESA_FORMAT_L_LATC1
:
548 case MESA_FORMAT_SIGNED_RED_RGTC1
:
549 case MESA_FORMAT_SIGNED_L_LATC1
:
550 case MESA_FORMAT_RG_RGTC2
:
551 case MESA_FORMAT_LA_LATC2
:
552 case MESA_FORMAT_SIGNED_RG_RGTC2
:
553 case MESA_FORMAT_SIGNED_LA_LATC2
:
554 return _mesa_get_compressed_rgtc_func(format
);
555 case MESA_FORMAT_ETC1_RGB8
:
556 return _mesa_get_etc_fetch_func(format
);
564 * Decompress a compressed texture image, returning a GL_RGBA/GL_FLOAT image.
565 * \param srcRowStride stride in bytes between rows of blocks in the
566 * compressed source image.
569 _mesa_decompress_image(gl_format format
, GLuint width
, GLuint height
,
570 const GLubyte
*src
, GLint srcRowStride
,
573 compressed_fetch_func fetch
;
575 GLuint bytes
, bw
, bh
;
578 bytes
= _mesa_get_format_bytes(format
);
579 _mesa_get_format_block_size(format
, &bw
, &bh
);
581 fetch
= _mesa_get_compressed_fetch_func(format
);
583 _mesa_problem(NULL
, "Unexpected format in _mesa_decompress_image()");
587 stride
= srcRowStride
* bh
/ bytes
;
589 for (j
= 0; j
< height
; j
++) {
590 for (i
= 0; i
< width
; i
++) {
591 fetch(src
, stride
, i
, j
, dest
);