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mesa: add support for GL_OES_compressed_ETC1_RGB8_texture
[mesa.git] / src / mesa / main / image.c
1 /*
2 * Mesa 3-D graphics library
3 * Version: 7.5
4 *
5 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
6 * Copyright (C) 2009 VMware, Inc. All Rights Reserved.
7 *
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:
14 *
15 * The above copyright notice and this permission notice shall be included
16 * in all copies or substantial portions of the Software.
17 *
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 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
22 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
23 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 */
25
26
27 /**
28 * \file image.c
29 * Image handling.
30 */
31
32
33 #include "glheader.h"
34 #include "colormac.h"
35 #include "image.h"
36 #include "imports.h"
37 #include "macros.h"
38 #include "mfeatures.h"
39 #include "mtypes.h"
40
41
42
43 /**
44 * \return GL_TRUE if type is packed pixel type, GL_FALSE otherwise.
45 */
46 GLboolean
47 _mesa_type_is_packed(GLenum type)
48 {
49 switch (type) {
50 case GL_UNSIGNED_BYTE_3_3_2:
51 case GL_UNSIGNED_BYTE_2_3_3_REV:
52 case MESA_UNSIGNED_BYTE_4_4:
53 case GL_UNSIGNED_SHORT_5_6_5:
54 case GL_UNSIGNED_SHORT_5_6_5_REV:
55 case GL_UNSIGNED_SHORT_4_4_4_4:
56 case GL_UNSIGNED_SHORT_4_4_4_4_REV:
57 case GL_UNSIGNED_SHORT_5_5_5_1:
58 case GL_UNSIGNED_SHORT_1_5_5_5_REV:
59 case GL_UNSIGNED_INT_8_8_8_8:
60 case GL_UNSIGNED_INT_8_8_8_8_REV:
61 case GL_UNSIGNED_INT_10_10_10_2:
62 case GL_UNSIGNED_INT_2_10_10_10_REV:
63 case GL_UNSIGNED_SHORT_8_8_MESA:
64 case GL_UNSIGNED_SHORT_8_8_REV_MESA:
65 case GL_UNSIGNED_INT_24_8_EXT:
66 case GL_UNSIGNED_INT_5_9_9_9_REV:
67 case GL_UNSIGNED_INT_10F_11F_11F_REV:
68 case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
69 return GL_TRUE;
70 }
71
72 return GL_FALSE;
73 }
74
75
76
77 /**
78 * Flip the order of the 2 bytes in each word in the given array.
79 *
80 * \param p array.
81 * \param n number of words.
82 */
83 void
84 _mesa_swap2( GLushort *p, GLuint n )
85 {
86 GLuint i;
87 for (i = 0; i < n; i++) {
88 p[i] = (p[i] >> 8) | ((p[i] << 8) & 0xff00);
89 }
90 }
91
92
93
94 /*
95 * Flip the order of the 4 bytes in each word in the given array.
96 */
97 void
98 _mesa_swap4( GLuint *p, GLuint n )
99 {
100 GLuint i, a, b;
101 for (i = 0; i < n; i++) {
102 b = p[i];
103 a = (b >> 24)
104 | ((b >> 8) & 0xff00)
105 | ((b << 8) & 0xff0000)
106 | ((b << 24) & 0xff000000);
107 p[i] = a;
108 }
109 }
110
111
112 /**
113 * Get the size of a GL data type.
114 *
115 * \param type GL data type.
116 *
117 * \return the size, in bytes, of the given data type, 0 if a GL_BITMAP, or -1
118 * if an invalid type enum.
119 */
120 GLint
121 _mesa_sizeof_type( GLenum type )
122 {
123 switch (type) {
124 case GL_BITMAP:
125 return 0;
126 case GL_UNSIGNED_BYTE:
127 return sizeof(GLubyte);
128 case GL_BYTE:
129 return sizeof(GLbyte);
130 case GL_UNSIGNED_SHORT:
131 return sizeof(GLushort);
132 case GL_SHORT:
133 return sizeof(GLshort);
134 case GL_UNSIGNED_INT:
135 return sizeof(GLuint);
136 case GL_INT:
137 return sizeof(GLint);
138 case GL_FLOAT:
139 return sizeof(GLfloat);
140 case GL_DOUBLE:
141 return sizeof(GLdouble);
142 case GL_HALF_FLOAT_ARB:
143 return sizeof(GLhalfARB);
144 case GL_FIXED:
145 return sizeof(GLfixed);
146 default:
147 return -1;
148 }
149 }
150
151
152 /**
153 * Same as _mesa_sizeof_type() but also accepting the packed pixel
154 * format data types.
155 */
156 GLint
157 _mesa_sizeof_packed_type( GLenum type )
158 {
159 switch (type) {
160 case GL_BITMAP:
161 return 0;
162 case GL_UNSIGNED_BYTE:
163 return sizeof(GLubyte);
164 case GL_BYTE:
165 return sizeof(GLbyte);
166 case GL_UNSIGNED_SHORT:
167 return sizeof(GLushort);
168 case GL_SHORT:
169 return sizeof(GLshort);
170 case GL_UNSIGNED_INT:
171 return sizeof(GLuint);
172 case GL_INT:
173 return sizeof(GLint);
174 case GL_HALF_FLOAT_ARB:
175 return sizeof(GLhalfARB);
176 case GL_FLOAT:
177 return sizeof(GLfloat);
178 case GL_UNSIGNED_BYTE_3_3_2:
179 case GL_UNSIGNED_BYTE_2_3_3_REV:
180 case MESA_UNSIGNED_BYTE_4_4:
181 return sizeof(GLubyte);
182 case GL_UNSIGNED_SHORT_5_6_5:
183 case GL_UNSIGNED_SHORT_5_6_5_REV:
184 case GL_UNSIGNED_SHORT_4_4_4_4:
185 case GL_UNSIGNED_SHORT_4_4_4_4_REV:
186 case GL_UNSIGNED_SHORT_5_5_5_1:
187 case GL_UNSIGNED_SHORT_1_5_5_5_REV:
188 case GL_UNSIGNED_SHORT_8_8_MESA:
189 case GL_UNSIGNED_SHORT_8_8_REV_MESA:
190 return sizeof(GLushort);
191 case GL_UNSIGNED_INT_8_8_8_8:
192 case GL_UNSIGNED_INT_8_8_8_8_REV:
193 case GL_UNSIGNED_INT_10_10_10_2:
194 case GL_UNSIGNED_INT_2_10_10_10_REV:
195 case GL_UNSIGNED_INT_24_8_EXT:
196 case GL_UNSIGNED_INT_5_9_9_9_REV:
197 case GL_UNSIGNED_INT_10F_11F_11F_REV:
198 return sizeof(GLuint);
199 case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
200 return 8;
201 default:
202 return -1;
203 }
204 }
205
206
207 /**
208 * Get the number of components in a pixel format.
209 *
210 * \param format pixel format.
211 *
212 * \return the number of components in the given format, or -1 if a bad format.
213 */
214 GLint
215 _mesa_components_in_format( GLenum format )
216 {
217 switch (format) {
218 case GL_COLOR_INDEX:
219 case GL_STENCIL_INDEX:
220 case GL_DEPTH_COMPONENT:
221 case GL_RED:
222 case GL_RED_INTEGER_EXT:
223 case GL_GREEN:
224 case GL_GREEN_INTEGER_EXT:
225 case GL_BLUE:
226 case GL_BLUE_INTEGER_EXT:
227 case GL_ALPHA:
228 case GL_ALPHA_INTEGER_EXT:
229 case GL_LUMINANCE:
230 case GL_LUMINANCE_INTEGER_EXT:
231 case GL_INTENSITY:
232 return 1;
233
234 case GL_LUMINANCE_ALPHA:
235 case GL_LUMINANCE_ALPHA_INTEGER_EXT:
236 case GL_RG:
237 case GL_YCBCR_MESA:
238 case GL_DEPTH_STENCIL_EXT:
239 case GL_DUDV_ATI:
240 case GL_DU8DV8_ATI:
241 return 2;
242
243 case GL_RGB:
244 case GL_BGR:
245 case GL_RGB_INTEGER_EXT:
246 case GL_BGR_INTEGER_EXT:
247 return 3;
248
249 case GL_RGBA:
250 case GL_BGRA:
251 case GL_ABGR_EXT:
252 case GL_RGBA_INTEGER_EXT:
253 case GL_BGRA_INTEGER_EXT:
254 return 4;
255
256 default:
257 return -1;
258 }
259 }
260
261
262 /**
263 * Get the bytes per pixel of pixel format type pair.
264 *
265 * \param format pixel format.
266 * \param type pixel type.
267 *
268 * \return bytes per pixel, or -1 if a bad format or type was given.
269 */
270 GLint
271 _mesa_bytes_per_pixel( GLenum format, GLenum type )
272 {
273 GLint comps = _mesa_components_in_format( format );
274 if (comps < 0)
275 return -1;
276
277 switch (type) {
278 case GL_BITMAP:
279 return 0; /* special case */
280 case GL_BYTE:
281 case GL_UNSIGNED_BYTE:
282 return comps * sizeof(GLubyte);
283 case GL_SHORT:
284 case GL_UNSIGNED_SHORT:
285 return comps * sizeof(GLshort);
286 case GL_INT:
287 case GL_UNSIGNED_INT:
288 return comps * sizeof(GLint);
289 case GL_FLOAT:
290 return comps * sizeof(GLfloat);
291 case GL_HALF_FLOAT_ARB:
292 return comps * sizeof(GLhalfARB);
293 case GL_UNSIGNED_BYTE_3_3_2:
294 case GL_UNSIGNED_BYTE_2_3_3_REV:
295 if (format == GL_RGB || format == GL_BGR ||
296 format == GL_RGB_INTEGER_EXT || format == GL_BGR_INTEGER_EXT)
297 return sizeof(GLubyte);
298 else
299 return -1; /* error */
300 case GL_UNSIGNED_SHORT_5_6_5:
301 case GL_UNSIGNED_SHORT_5_6_5_REV:
302 if (format == GL_RGB || format == GL_BGR ||
303 format == GL_RGB_INTEGER_EXT || format == GL_BGR_INTEGER_EXT)
304 return sizeof(GLushort);
305 else
306 return -1; /* error */
307 case GL_UNSIGNED_SHORT_4_4_4_4:
308 case GL_UNSIGNED_SHORT_4_4_4_4_REV:
309 case GL_UNSIGNED_SHORT_5_5_5_1:
310 case GL_UNSIGNED_SHORT_1_5_5_5_REV:
311 if (format == GL_RGBA || format == GL_BGRA || format == GL_ABGR_EXT ||
312 format == GL_RGBA_INTEGER_EXT || format == GL_BGRA_INTEGER_EXT)
313 return sizeof(GLushort);
314 else
315 return -1;
316 case GL_UNSIGNED_INT_8_8_8_8:
317 case GL_UNSIGNED_INT_8_8_8_8_REV:
318 case GL_UNSIGNED_INT_10_10_10_2:
319 case GL_UNSIGNED_INT_2_10_10_10_REV:
320 if (format == GL_RGBA || format == GL_BGRA || format == GL_ABGR_EXT ||
321 format == GL_RGBA_INTEGER_EXT || format == GL_BGRA_INTEGER_EXT)
322 return sizeof(GLuint);
323 else
324 return -1;
325 case GL_UNSIGNED_SHORT_8_8_MESA:
326 case GL_UNSIGNED_SHORT_8_8_REV_MESA:
327 if (format == GL_YCBCR_MESA)
328 return sizeof(GLushort);
329 else
330 return -1;
331 case GL_UNSIGNED_INT_24_8_EXT:
332 if (format == GL_DEPTH_STENCIL_EXT)
333 return sizeof(GLuint);
334 else
335 return -1;
336 case GL_UNSIGNED_INT_5_9_9_9_REV:
337 if (format == GL_RGB)
338 return sizeof(GLuint);
339 else
340 return -1;
341 case GL_UNSIGNED_INT_10F_11F_11F_REV:
342 if (format == GL_RGB)
343 return sizeof(GLuint);
344 else
345 return -1;
346 case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
347 if (format == GL_DEPTH_STENCIL)
348 return 8;
349 else
350 return -1;
351 default:
352 return -1;
353 }
354 }
355
356
357 /**
358 * Test for a legal pixel format and type.
359 *
360 * \param format pixel format.
361 * \param type pixel type.
362 *
363 * \return GL_TRUE if the given pixel format and type are legal, or GL_FALSE
364 * otherwise.
365 */
366 GLboolean
367 _mesa_is_legal_format_and_type(const struct gl_context *ctx,
368 GLenum format, GLenum type)
369 {
370 switch (format) {
371 case GL_COLOR_INDEX:
372 case GL_STENCIL_INDEX:
373 switch (type) {
374 case GL_BITMAP:
375 case GL_BYTE:
376 case GL_UNSIGNED_BYTE:
377 case GL_SHORT:
378 case GL_UNSIGNED_SHORT:
379 case GL_INT:
380 case GL_UNSIGNED_INT:
381 case GL_FLOAT:
382 return GL_TRUE;
383 case GL_HALF_FLOAT_ARB:
384 return ctx->Extensions.ARB_half_float_pixel;
385 default:
386 return GL_FALSE;
387 }
388 case GL_RED:
389 case GL_GREEN:
390 case GL_BLUE:
391 case GL_ALPHA:
392 #if 0 /* not legal! see table 3.6 of the 1.5 spec */
393 case GL_INTENSITY:
394 #endif
395 case GL_LUMINANCE:
396 case GL_LUMINANCE_ALPHA:
397 case GL_DEPTH_COMPONENT:
398 switch (type) {
399 case GL_BYTE:
400 case GL_UNSIGNED_BYTE:
401 case GL_SHORT:
402 case GL_UNSIGNED_SHORT:
403 case GL_INT:
404 case GL_UNSIGNED_INT:
405 case GL_FLOAT:
406 return GL_TRUE;
407 case GL_HALF_FLOAT_ARB:
408 return ctx->Extensions.ARB_half_float_pixel;
409 default:
410 return GL_FALSE;
411 }
412 case GL_RG:
413 if (!ctx->Extensions.ARB_texture_rg)
414 return GL_FALSE;
415
416 switch (type) {
417 case GL_BYTE:
418 case GL_UNSIGNED_BYTE:
419 case GL_SHORT:
420 case GL_UNSIGNED_SHORT:
421 case GL_INT:
422 case GL_UNSIGNED_INT:
423 case GL_FLOAT:
424 return GL_TRUE;
425 case GL_HALF_FLOAT_ARB:
426 return ctx->Extensions.ARB_half_float_pixel;
427 default:
428 return GL_FALSE;
429 }
430 case GL_RGB:
431 switch (type) {
432 case GL_BYTE:
433 case GL_UNSIGNED_BYTE:
434 case GL_SHORT:
435 case GL_UNSIGNED_SHORT:
436 case GL_INT:
437 case GL_UNSIGNED_INT:
438 case GL_FLOAT:
439 case GL_UNSIGNED_BYTE_3_3_2:
440 case GL_UNSIGNED_BYTE_2_3_3_REV:
441 case GL_UNSIGNED_SHORT_5_6_5:
442 case GL_UNSIGNED_SHORT_5_6_5_REV:
443 return GL_TRUE;
444 case GL_HALF_FLOAT_ARB:
445 return ctx->Extensions.ARB_half_float_pixel;
446 case GL_UNSIGNED_INT_5_9_9_9_REV:
447 return ctx->Extensions.EXT_texture_shared_exponent;
448 case GL_UNSIGNED_INT_10F_11F_11F_REV:
449 return ctx->Extensions.EXT_packed_float;
450 default:
451 return GL_FALSE;
452 }
453 case GL_BGR:
454 switch (type) {
455 /* NOTE: no packed types are supported with BGR. That's
456 * intentional, according to the GL spec.
457 */
458 case GL_BYTE:
459 case GL_UNSIGNED_BYTE:
460 case GL_SHORT:
461 case GL_UNSIGNED_SHORT:
462 case GL_INT:
463 case GL_UNSIGNED_INT:
464 case GL_FLOAT:
465 return GL_TRUE;
466 case GL_HALF_FLOAT_ARB:
467 return ctx->Extensions.ARB_half_float_pixel;
468 default:
469 return GL_FALSE;
470 }
471 case GL_RGBA:
472 case GL_BGRA:
473 case GL_ABGR_EXT:
474 switch (type) {
475 case GL_BYTE:
476 case GL_UNSIGNED_BYTE:
477 case GL_SHORT:
478 case GL_UNSIGNED_SHORT:
479 case GL_INT:
480 case GL_UNSIGNED_INT:
481 case GL_FLOAT:
482 case GL_UNSIGNED_SHORT_4_4_4_4:
483 case GL_UNSIGNED_SHORT_4_4_4_4_REV:
484 case GL_UNSIGNED_SHORT_5_5_5_1:
485 case GL_UNSIGNED_SHORT_1_5_5_5_REV:
486 case GL_UNSIGNED_INT_8_8_8_8:
487 case GL_UNSIGNED_INT_8_8_8_8_REV:
488 case GL_UNSIGNED_INT_10_10_10_2:
489 case GL_UNSIGNED_INT_2_10_10_10_REV:
490 return GL_TRUE;
491 case GL_HALF_FLOAT_ARB:
492 return ctx->Extensions.ARB_half_float_pixel;
493 default:
494 return GL_FALSE;
495 }
496 case GL_YCBCR_MESA:
497 if (type == GL_UNSIGNED_SHORT_8_8_MESA ||
498 type == GL_UNSIGNED_SHORT_8_8_REV_MESA)
499 return GL_TRUE;
500 else
501 return GL_FALSE;
502 case GL_DEPTH_STENCIL_EXT:
503 if ((ctx->Extensions.EXT_packed_depth_stencil &&
504 type == GL_UNSIGNED_INT_24_8_EXT) ||
505 (ctx->Extensions.ARB_depth_buffer_float &&
506 type == GL_FLOAT_32_UNSIGNED_INT_24_8_REV))
507 return GL_TRUE;
508 else
509 return GL_FALSE;
510 case GL_DUDV_ATI:
511 case GL_DU8DV8_ATI:
512 switch (type) {
513 case GL_BYTE:
514 case GL_UNSIGNED_BYTE:
515 case GL_SHORT:
516 case GL_UNSIGNED_SHORT:
517 case GL_INT:
518 case GL_UNSIGNED_INT:
519 case GL_FLOAT:
520 return GL_TRUE;
521 default:
522 return GL_FALSE;
523 }
524
525 /* integer-valued formats */
526 case GL_RED_INTEGER_EXT:
527 case GL_GREEN_INTEGER_EXT:
528 case GL_BLUE_INTEGER_EXT:
529 case GL_ALPHA_INTEGER_EXT:
530 switch (type) {
531 case GL_BYTE:
532 case GL_UNSIGNED_BYTE:
533 case GL_SHORT:
534 case GL_UNSIGNED_SHORT:
535 case GL_INT:
536 case GL_UNSIGNED_INT:
537 return ctx->Extensions.EXT_texture_integer;
538 default:
539 return GL_FALSE;
540 }
541
542 case GL_RGB_INTEGER_EXT:
543 switch (type) {
544 case GL_BYTE:
545 case GL_UNSIGNED_BYTE:
546 case GL_SHORT:
547 case GL_UNSIGNED_SHORT:
548 case GL_INT:
549 case GL_UNSIGNED_INT:
550 return ctx->Extensions.EXT_texture_integer;
551 case GL_UNSIGNED_BYTE_3_3_2:
552 case GL_UNSIGNED_BYTE_2_3_3_REV:
553 case GL_UNSIGNED_SHORT_5_6_5:
554 case GL_UNSIGNED_SHORT_5_6_5_REV:
555 return ctx->Extensions.ARB_texture_rgb10_a2ui;
556 default:
557 return GL_FALSE;
558 }
559
560 case GL_BGR_INTEGER_EXT:
561 switch (type) {
562 case GL_BYTE:
563 case GL_UNSIGNED_BYTE:
564 case GL_SHORT:
565 case GL_UNSIGNED_SHORT:
566 case GL_INT:
567 case GL_UNSIGNED_INT:
568 /* NOTE: no packed formats w/ BGR format */
569 return ctx->Extensions.EXT_texture_integer;
570 default:
571 return GL_FALSE;
572 }
573
574 case GL_RGBA_INTEGER_EXT:
575 case GL_BGRA_INTEGER_EXT:
576 switch (type) {
577 case GL_BYTE:
578 case GL_UNSIGNED_BYTE:
579 case GL_SHORT:
580 case GL_UNSIGNED_SHORT:
581 case GL_INT:
582 case GL_UNSIGNED_INT:
583 return ctx->Extensions.EXT_texture_integer;
584 case GL_UNSIGNED_SHORT_4_4_4_4:
585 case GL_UNSIGNED_SHORT_4_4_4_4_REV:
586 case GL_UNSIGNED_SHORT_5_5_5_1:
587 case GL_UNSIGNED_SHORT_1_5_5_5_REV:
588 case GL_UNSIGNED_INT_8_8_8_8:
589 case GL_UNSIGNED_INT_8_8_8_8_REV:
590 case GL_UNSIGNED_INT_10_10_10_2:
591 case GL_UNSIGNED_INT_2_10_10_10_REV:
592 return ctx->Extensions.ARB_texture_rgb10_a2ui;
593 default:
594 return GL_FALSE;
595 }
596
597 case GL_LUMINANCE_INTEGER_EXT:
598 case GL_LUMINANCE_ALPHA_INTEGER_EXT:
599 switch (type) {
600 case GL_BYTE:
601 case GL_UNSIGNED_BYTE:
602 case GL_SHORT:
603 case GL_UNSIGNED_SHORT:
604 case GL_INT:
605 case GL_UNSIGNED_INT:
606 return ctx->Extensions.EXT_texture_integer;
607 default:
608 return GL_FALSE;
609 }
610
611 default:
612 ; /* fall-through */
613 }
614 return GL_FALSE;
615 }
616
617
618 /**
619 * Test if the given image format is a color/RGBA format (i.e., not color
620 * index, depth, stencil, etc).
621 * \param format the image format value (may by an internal texture format)
622 * \return GL_TRUE if its a color/RGBA format, GL_FALSE otherwise.
623 */
624 GLboolean
625 _mesa_is_color_format(GLenum format)
626 {
627 switch (format) {
628 case GL_RED:
629 case GL_GREEN:
630 case GL_BLUE:
631 case GL_ALPHA:
632 case GL_ALPHA4:
633 case GL_ALPHA8:
634 case GL_ALPHA12:
635 case GL_ALPHA16:
636 case 1:
637 case GL_LUMINANCE:
638 case GL_LUMINANCE4:
639 case GL_LUMINANCE8:
640 case GL_LUMINANCE12:
641 case GL_LUMINANCE16:
642 case 2:
643 case GL_LUMINANCE_ALPHA:
644 case GL_LUMINANCE4_ALPHA4:
645 case GL_LUMINANCE6_ALPHA2:
646 case GL_LUMINANCE8_ALPHA8:
647 case GL_LUMINANCE12_ALPHA4:
648 case GL_LUMINANCE12_ALPHA12:
649 case GL_LUMINANCE16_ALPHA16:
650 case GL_INTENSITY:
651 case GL_INTENSITY4:
652 case GL_INTENSITY8:
653 case GL_INTENSITY12:
654 case GL_INTENSITY16:
655 case GL_R8:
656 case GL_R16:
657 case GL_RG:
658 case GL_RG8:
659 case GL_RG16:
660 case 3:
661 case GL_RGB:
662 case GL_BGR:
663 case GL_R3_G3_B2:
664 case GL_RGB4:
665 case GL_RGB5:
666 case GL_RGB8:
667 case GL_RGB10:
668 case GL_RGB12:
669 case GL_RGB16:
670 case 4:
671 case GL_ABGR_EXT:
672 case GL_RGBA:
673 case GL_BGRA:
674 case GL_RGBA2:
675 case GL_RGBA4:
676 case GL_RGB5_A1:
677 case GL_RGBA8:
678 case GL_RGB10_A2:
679 case GL_RGBA12:
680 case GL_RGBA16:
681 /* float texture formats */
682 case GL_ALPHA16F_ARB:
683 case GL_ALPHA32F_ARB:
684 case GL_LUMINANCE16F_ARB:
685 case GL_LUMINANCE32F_ARB:
686 case GL_LUMINANCE_ALPHA16F_ARB:
687 case GL_LUMINANCE_ALPHA32F_ARB:
688 case GL_INTENSITY16F_ARB:
689 case GL_INTENSITY32F_ARB:
690 case GL_R16F:
691 case GL_R32F:
692 case GL_RG16F:
693 case GL_RG32F:
694 case GL_RGB16F_ARB:
695 case GL_RGB32F_ARB:
696 case GL_RGBA16F_ARB:
697 case GL_RGBA32F_ARB:
698 /* compressed formats */
699 case GL_COMPRESSED_ALPHA:
700 case GL_COMPRESSED_LUMINANCE:
701 case GL_COMPRESSED_LUMINANCE_ALPHA:
702 case GL_COMPRESSED_INTENSITY:
703 case GL_COMPRESSED_RED:
704 case GL_COMPRESSED_RG:
705 case GL_COMPRESSED_RGB:
706 case GL_COMPRESSED_RGBA:
707 case GL_RGB_S3TC:
708 case GL_RGB4_S3TC:
709 case GL_RGBA_S3TC:
710 case GL_RGBA4_S3TC:
711 case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
712 case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
713 case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
714 case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
715 case GL_COMPRESSED_RGB_FXT1_3DFX:
716 case GL_COMPRESSED_RGBA_FXT1_3DFX:
717 #if FEATURE_EXT_texture_sRGB
718 case GL_SRGB_EXT:
719 case GL_SRGB8_EXT:
720 case GL_SRGB_ALPHA_EXT:
721 case GL_SRGB8_ALPHA8_EXT:
722 case GL_SLUMINANCE_ALPHA_EXT:
723 case GL_SLUMINANCE8_ALPHA8_EXT:
724 case GL_SLUMINANCE_EXT:
725 case GL_SLUMINANCE8_EXT:
726 case GL_COMPRESSED_SRGB_EXT:
727 case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
728 case GL_COMPRESSED_SRGB_ALPHA_EXT:
729 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
730 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
731 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
732 case GL_COMPRESSED_SLUMINANCE_EXT:
733 case GL_COMPRESSED_SLUMINANCE_ALPHA_EXT:
734 #endif /* FEATURE_EXT_texture_sRGB */
735 case GL_COMPRESSED_RED_RGTC1:
736 case GL_COMPRESSED_SIGNED_RED_RGTC1:
737 case GL_COMPRESSED_RG_RGTC2:
738 case GL_COMPRESSED_SIGNED_RG_RGTC2:
739 case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
740 case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
741 case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
742 case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
743 case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
744 case GL_ETC1_RGB8_OES:
745 /* generic integer formats */
746 case GL_RED_INTEGER_EXT:
747 case GL_GREEN_INTEGER_EXT:
748 case GL_BLUE_INTEGER_EXT:
749 case GL_ALPHA_INTEGER_EXT:
750 case GL_RGB_INTEGER_EXT:
751 case GL_RGBA_INTEGER_EXT:
752 case GL_BGR_INTEGER_EXT:
753 case GL_BGRA_INTEGER_EXT:
754 case GL_LUMINANCE_INTEGER_EXT:
755 case GL_LUMINANCE_ALPHA_INTEGER_EXT:
756 /* sized integer formats */
757 case GL_RGBA32UI_EXT:
758 case GL_RGB32UI_EXT:
759 case GL_ALPHA32UI_EXT:
760 case GL_INTENSITY32UI_EXT:
761 case GL_LUMINANCE32UI_EXT:
762 case GL_LUMINANCE_ALPHA32UI_EXT:
763 case GL_RGBA16UI_EXT:
764 case GL_RGB16UI_EXT:
765 case GL_ALPHA16UI_EXT:
766 case GL_INTENSITY16UI_EXT:
767 case GL_LUMINANCE16UI_EXT:
768 case GL_LUMINANCE_ALPHA16UI_EXT:
769 case GL_RGBA8UI_EXT:
770 case GL_RGB8UI_EXT:
771 case GL_ALPHA8UI_EXT:
772 case GL_INTENSITY8UI_EXT:
773 case GL_LUMINANCE8UI_EXT:
774 case GL_LUMINANCE_ALPHA8UI_EXT:
775 case GL_RGBA32I_EXT:
776 case GL_RGB32I_EXT:
777 case GL_ALPHA32I_EXT:
778 case GL_INTENSITY32I_EXT:
779 case GL_LUMINANCE32I_EXT:
780 case GL_LUMINANCE_ALPHA32I_EXT:
781 case GL_RGBA16I_EXT:
782 case GL_RGB16I_EXT:
783 case GL_ALPHA16I_EXT:
784 case GL_INTENSITY16I_EXT:
785 case GL_LUMINANCE16I_EXT:
786 case GL_LUMINANCE_ALPHA16I_EXT:
787 case GL_RGBA8I_EXT:
788 case GL_RGB8I_EXT:
789 case GL_ALPHA8I_EXT:
790 case GL_INTENSITY8I_EXT:
791 case GL_LUMINANCE8I_EXT:
792 case GL_LUMINANCE_ALPHA8I_EXT:
793 /* signed, normalized texture formats */
794 case GL_RED_SNORM:
795 case GL_R8_SNORM:
796 case GL_R16_SNORM:
797 case GL_RG_SNORM:
798 case GL_RG8_SNORM:
799 case GL_RG16_SNORM:
800 case GL_RGB_SNORM:
801 case GL_RGB8_SNORM:
802 case GL_RGB16_SNORM:
803 case GL_RGBA_SNORM:
804 case GL_RGBA8_SNORM:
805 case GL_RGBA16_SNORM:
806 case GL_ALPHA_SNORM:
807 case GL_ALPHA8_SNORM:
808 case GL_ALPHA16_SNORM:
809 case GL_LUMINANCE_SNORM:
810 case GL_LUMINANCE8_SNORM:
811 case GL_LUMINANCE16_SNORM:
812 case GL_LUMINANCE_ALPHA_SNORM:
813 case GL_LUMINANCE8_ALPHA8_SNORM:
814 case GL_LUMINANCE16_ALPHA16_SNORM:
815 case GL_INTENSITY_SNORM:
816 case GL_INTENSITY8_SNORM:
817 case GL_INTENSITY16_SNORM:
818 case GL_RGB9_E5:
819 case GL_R11F_G11F_B10F:
820 case GL_RGB10_A2UI:
821 return GL_TRUE;
822 case GL_YCBCR_MESA: /* not considered to be RGB */
823 /* fall-through */
824 default:
825 return GL_FALSE;
826 }
827 }
828
829
830 /**
831 * Test if the given image format is a depth component format.
832 */
833 GLboolean
834 _mesa_is_depth_format(GLenum format)
835 {
836 switch (format) {
837 case GL_DEPTH_COMPONENT:
838 case GL_DEPTH_COMPONENT16:
839 case GL_DEPTH_COMPONENT24:
840 case GL_DEPTH_COMPONENT32:
841 case GL_DEPTH_COMPONENT32F:
842 return GL_TRUE;
843 default:
844 return GL_FALSE;
845 }
846 }
847
848
849 /**
850 * Test if the given image format is a stencil format.
851 */
852 GLboolean
853 _mesa_is_stencil_format(GLenum format)
854 {
855 switch (format) {
856 case GL_STENCIL_INDEX:
857 return GL_TRUE;
858 default:
859 return GL_FALSE;
860 }
861 }
862
863
864 /**
865 * Test if the given image format is a YCbCr format.
866 */
867 GLboolean
868 _mesa_is_ycbcr_format(GLenum format)
869 {
870 switch (format) {
871 case GL_YCBCR_MESA:
872 return GL_TRUE;
873 default:
874 return GL_FALSE;
875 }
876 }
877
878
879 /**
880 * Test if the given image format is a depth+stencil format.
881 */
882 GLboolean
883 _mesa_is_depthstencil_format(GLenum format)
884 {
885 switch (format) {
886 case GL_DEPTH24_STENCIL8_EXT:
887 case GL_DEPTH_STENCIL_EXT:
888 case GL_DEPTH32F_STENCIL8:
889 return GL_TRUE;
890 default:
891 return GL_FALSE;
892 }
893 }
894
895
896 /**
897 * Test if the given image format is a depth or stencil format.
898 */
899 GLboolean
900 _mesa_is_depth_or_stencil_format(GLenum format)
901 {
902 switch (format) {
903 case GL_DEPTH_COMPONENT:
904 case GL_DEPTH_COMPONENT16:
905 case GL_DEPTH_COMPONENT24:
906 case GL_DEPTH_COMPONENT32:
907 case GL_STENCIL_INDEX:
908 case GL_STENCIL_INDEX1_EXT:
909 case GL_STENCIL_INDEX4_EXT:
910 case GL_STENCIL_INDEX8_EXT:
911 case GL_STENCIL_INDEX16_EXT:
912 case GL_DEPTH_STENCIL_EXT:
913 case GL_DEPTH24_STENCIL8_EXT:
914 case GL_DEPTH_COMPONENT32F:
915 case GL_DEPTH32F_STENCIL8:
916 return GL_TRUE;
917 default:
918 return GL_FALSE;
919 }
920 }
921
922
923 /**
924 * Test if the given image format is a dudv format.
925 */
926 GLboolean
927 _mesa_is_dudv_format(GLenum format)
928 {
929 switch (format) {
930 case GL_DUDV_ATI:
931 case GL_DU8DV8_ATI:
932 return GL_TRUE;
933 default:
934 return GL_FALSE;
935 }
936 }
937
938
939 /**
940 * Test if the given format is an integer (non-normalized) format.
941 */
942 GLboolean
943 _mesa_is_integer_format(GLenum format)
944 {
945 switch (format) {
946 /* generic integer formats */
947 case GL_RED_INTEGER_EXT:
948 case GL_GREEN_INTEGER_EXT:
949 case GL_BLUE_INTEGER_EXT:
950 case GL_ALPHA_INTEGER_EXT:
951 case GL_RGB_INTEGER_EXT:
952 case GL_RGBA_INTEGER_EXT:
953 case GL_BGR_INTEGER_EXT:
954 case GL_BGRA_INTEGER_EXT:
955 case GL_LUMINANCE_INTEGER_EXT:
956 case GL_LUMINANCE_ALPHA_INTEGER_EXT:
957 /* specific integer formats */
958 case GL_RGBA32UI_EXT:
959 case GL_RGB32UI_EXT:
960 case GL_RG32UI:
961 case GL_R32UI:
962 case GL_ALPHA32UI_EXT:
963 case GL_INTENSITY32UI_EXT:
964 case GL_LUMINANCE32UI_EXT:
965 case GL_LUMINANCE_ALPHA32UI_EXT:
966 case GL_RGBA16UI_EXT:
967 case GL_RGB16UI_EXT:
968 case GL_RG16UI:
969 case GL_R16UI:
970 case GL_ALPHA16UI_EXT:
971 case GL_INTENSITY16UI_EXT:
972 case GL_LUMINANCE16UI_EXT:
973 case GL_LUMINANCE_ALPHA16UI_EXT:
974 case GL_RGBA8UI_EXT:
975 case GL_RGB8UI_EXT:
976 case GL_RG8UI:
977 case GL_R8UI:
978 case GL_ALPHA8UI_EXT:
979 case GL_INTENSITY8UI_EXT:
980 case GL_LUMINANCE8UI_EXT:
981 case GL_LUMINANCE_ALPHA8UI_EXT:
982 case GL_RGBA32I_EXT:
983 case GL_RGB32I_EXT:
984 case GL_RG32I:
985 case GL_R32I:
986 case GL_ALPHA32I_EXT:
987 case GL_INTENSITY32I_EXT:
988 case GL_LUMINANCE32I_EXT:
989 case GL_LUMINANCE_ALPHA32I_EXT:
990 case GL_RGBA16I_EXT:
991 case GL_RGB16I_EXT:
992 case GL_RG16I:
993 case GL_R16I:
994 case GL_ALPHA16I_EXT:
995 case GL_INTENSITY16I_EXT:
996 case GL_LUMINANCE16I_EXT:
997 case GL_LUMINANCE_ALPHA16I_EXT:
998 case GL_RGBA8I_EXT:
999 case GL_RGB8I_EXT:
1000 case GL_RG8I:
1001 case GL_R8I:
1002 case GL_ALPHA8I_EXT:
1003 case GL_INTENSITY8I_EXT:
1004 case GL_LUMINANCE8I_EXT:
1005 case GL_LUMINANCE_ALPHA8I_EXT:
1006 case GL_RGB10_A2UI:
1007 return GL_TRUE;
1008 default:
1009 return GL_FALSE;
1010 }
1011 }
1012
1013
1014 /**
1015 * Test if an image format is a supported compressed format.
1016 * \param format the internal format token provided by the user.
1017 * \return GL_TRUE if compressed, GL_FALSE if uncompressed
1018 */
1019 GLboolean
1020 _mesa_is_compressed_format(struct gl_context *ctx, GLenum format)
1021 {
1022 switch (format) {
1023 case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
1024 case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
1025 case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
1026 case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
1027 return ctx->Extensions.EXT_texture_compression_s3tc;
1028 case GL_RGB_S3TC:
1029 case GL_RGB4_S3TC:
1030 case GL_RGBA_S3TC:
1031 case GL_RGBA4_S3TC:
1032 return ctx->Extensions.S3_s3tc;
1033 case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
1034 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
1035 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
1036 case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
1037 return ctx->Extensions.EXT_texture_sRGB
1038 && ctx->Extensions.EXT_texture_compression_s3tc;
1039 case GL_COMPRESSED_RGB_FXT1_3DFX:
1040 case GL_COMPRESSED_RGBA_FXT1_3DFX:
1041 return ctx->Extensions.TDFX_texture_compression_FXT1;
1042 case GL_COMPRESSED_RED_RGTC1:
1043 case GL_COMPRESSED_SIGNED_RED_RGTC1:
1044 case GL_COMPRESSED_RG_RGTC2:
1045 case GL_COMPRESSED_SIGNED_RG_RGTC2:
1046 return ctx->Extensions.ARB_texture_compression_rgtc;
1047 case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
1048 case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
1049 case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
1050 case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
1051 return ctx->Extensions.EXT_texture_compression_latc;
1052 case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
1053 return ctx->Extensions.ATI_texture_compression_3dc;
1054 case GL_ETC1_RGB8_OES:
1055 return ctx->Extensions.OES_compressed_ETC1_RGB8_texture;
1056 #if FEATURE_ES
1057 case GL_PALETTE4_RGB8_OES:
1058 case GL_PALETTE4_RGBA8_OES:
1059 case GL_PALETTE4_R5_G6_B5_OES:
1060 case GL_PALETTE4_RGBA4_OES:
1061 case GL_PALETTE4_RGB5_A1_OES:
1062 case GL_PALETTE8_RGB8_OES:
1063 case GL_PALETTE8_RGBA8_OES:
1064 case GL_PALETTE8_R5_G6_B5_OES:
1065 case GL_PALETTE8_RGBA4_OES:
1066 case GL_PALETTE8_RGB5_A1_OES:
1067 return ctx->API == API_OPENGLES;
1068 #endif
1069 default:
1070 return GL_FALSE;
1071 }
1072 }
1073
1074
1075 /**
1076 * Does the given base texture/renderbuffer format have the channel
1077 * named by 'pname'?
1078 */
1079 GLboolean
1080 _mesa_base_format_has_channel(GLenum base_format, GLenum pname)
1081 {
1082 switch (pname) {
1083 case GL_TEXTURE_RED_SIZE:
1084 case GL_TEXTURE_RED_TYPE:
1085 case GL_RENDERBUFFER_RED_SIZE_EXT:
1086 case GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE:
1087 if (base_format == GL_RED ||
1088 base_format == GL_RG ||
1089 base_format == GL_RGB ||
1090 base_format == GL_RGBA) {
1091 return GL_TRUE;
1092 }
1093 return GL_FALSE;
1094 case GL_TEXTURE_GREEN_SIZE:
1095 case GL_TEXTURE_GREEN_TYPE:
1096 case GL_RENDERBUFFER_GREEN_SIZE_EXT:
1097 case GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE:
1098 if (base_format == GL_RG ||
1099 base_format == GL_RGB ||
1100 base_format == GL_RGBA) {
1101 return GL_TRUE;
1102 }
1103 return GL_FALSE;
1104 case GL_TEXTURE_BLUE_SIZE:
1105 case GL_TEXTURE_BLUE_TYPE:
1106 case GL_RENDERBUFFER_BLUE_SIZE_EXT:
1107 case GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE:
1108 if (base_format == GL_RGB ||
1109 base_format == GL_RGBA) {
1110 return GL_TRUE;
1111 }
1112 return GL_FALSE;
1113 case GL_TEXTURE_ALPHA_SIZE:
1114 case GL_TEXTURE_ALPHA_TYPE:
1115 case GL_RENDERBUFFER_ALPHA_SIZE_EXT:
1116 case GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE:
1117 if (base_format == GL_RGBA ||
1118 base_format == GL_ALPHA ||
1119 base_format == GL_LUMINANCE_ALPHA) {
1120 return GL_TRUE;
1121 }
1122 return GL_FALSE;
1123 case GL_TEXTURE_LUMINANCE_SIZE:
1124 case GL_TEXTURE_LUMINANCE_TYPE:
1125 if (base_format == GL_LUMINANCE ||
1126 base_format == GL_LUMINANCE_ALPHA) {
1127 return GL_TRUE;
1128 }
1129 return GL_FALSE;
1130 case GL_TEXTURE_INTENSITY_SIZE:
1131 case GL_TEXTURE_INTENSITY_TYPE:
1132 if (base_format == GL_INTENSITY) {
1133 return GL_TRUE;
1134 }
1135 return GL_FALSE;
1136 case GL_TEXTURE_DEPTH_SIZE:
1137 case GL_TEXTURE_DEPTH_TYPE:
1138 case GL_RENDERBUFFER_DEPTH_SIZE_EXT:
1139 case GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE:
1140 if (base_format == GL_DEPTH_STENCIL ||
1141 base_format == GL_DEPTH_COMPONENT) {
1142 return GL_TRUE;
1143 }
1144 return GL_FALSE;
1145 case GL_RENDERBUFFER_STENCIL_SIZE_EXT:
1146 case GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE:
1147 if (base_format == GL_DEPTH_STENCIL ||
1148 base_format == GL_STENCIL_INDEX) {
1149 return GL_TRUE;
1150 }
1151 return GL_FALSE;
1152 default:
1153 _mesa_warning(NULL, "%s: Unexpected channel token 0x%x\n",
1154 __FUNCTION__, pname);
1155 return GL_FALSE;
1156 }
1157
1158 return GL_FALSE;
1159 }
1160
1161
1162 /**
1163 * Return the address of a specific pixel in an image (1D, 2D or 3D).
1164 *
1165 * Pixel unpacking/packing parameters are observed according to \p packing.
1166 *
1167 * \param dimensions either 1, 2 or 3 to indicate dimensionality of image
1168 * \param image starting address of image data
1169 * \param width the image width
1170 * \param height theimage height
1171 * \param format the pixel format
1172 * \param type the pixel data type
1173 * \param packing the pixelstore attributes
1174 * \param img which image in the volume (0 for 1D or 2D images)
1175 * \param row row of pixel in the image (0 for 1D images)
1176 * \param column column of pixel in the image
1177 *
1178 * \return address of pixel on success, or NULL on error.
1179 *
1180 * \sa gl_pixelstore_attrib.
1181 */
1182 GLvoid *
1183 _mesa_image_address( GLuint dimensions,
1184 const struct gl_pixelstore_attrib *packing,
1185 const GLvoid *image,
1186 GLsizei width, GLsizei height,
1187 GLenum format, GLenum type,
1188 GLint img, GLint row, GLint column )
1189 {
1190 GLint alignment; /* 1, 2 or 4 */
1191 GLint pixels_per_row;
1192 GLint rows_per_image;
1193 GLint skiprows;
1194 GLint skippixels;
1195 GLint skipimages; /* for 3-D volume images */
1196 GLubyte *pixel_addr;
1197
1198 ASSERT(dimensions >= 1 && dimensions <= 3);
1199
1200 alignment = packing->Alignment;
1201 if (packing->RowLength > 0) {
1202 pixels_per_row = packing->RowLength;
1203 }
1204 else {
1205 pixels_per_row = width;
1206 }
1207 if (packing->ImageHeight > 0) {
1208 rows_per_image = packing->ImageHeight;
1209 }
1210 else {
1211 rows_per_image = height;
1212 }
1213
1214 skippixels = packing->SkipPixels;
1215 /* Note: SKIP_ROWS _is_ used for 1D images */
1216 skiprows = packing->SkipRows;
1217 /* Note: SKIP_IMAGES is only used for 3D images */
1218 skipimages = (dimensions == 3) ? packing->SkipImages : 0;
1219
1220 if (type == GL_BITMAP) {
1221 /* BITMAP data */
1222 GLint comp_per_pixel; /* components per pixel */
1223 GLint bytes_per_comp; /* bytes per component */
1224 GLint bytes_per_row;
1225 GLint bytes_per_image;
1226
1227 /* Compute bytes per component */
1228 bytes_per_comp = _mesa_sizeof_packed_type( type );
1229 if (bytes_per_comp < 0) {
1230 return NULL;
1231 }
1232
1233 /* Compute number of components per pixel */
1234 comp_per_pixel = _mesa_components_in_format( format );
1235 if (comp_per_pixel < 0) {
1236 return NULL;
1237 }
1238
1239 bytes_per_row = alignment
1240 * CEILING( comp_per_pixel*pixels_per_row, 8*alignment );
1241
1242 bytes_per_image = bytes_per_row * rows_per_image;
1243
1244 pixel_addr = (GLubyte *) image
1245 + (skipimages + img) * bytes_per_image
1246 + (skiprows + row) * bytes_per_row
1247 + (skippixels + column) / 8;
1248 }
1249 else {
1250 /* Non-BITMAP data */
1251 GLint bytes_per_pixel, bytes_per_row, remainder, bytes_per_image;
1252 GLint topOfImage;
1253
1254 bytes_per_pixel = _mesa_bytes_per_pixel( format, type );
1255
1256 /* The pixel type and format should have been error checked earlier */
1257 assert(bytes_per_pixel > 0);
1258
1259 bytes_per_row = pixels_per_row * bytes_per_pixel;
1260 remainder = bytes_per_row % alignment;
1261 if (remainder > 0)
1262 bytes_per_row += (alignment - remainder);
1263
1264 ASSERT(bytes_per_row % alignment == 0);
1265
1266 bytes_per_image = bytes_per_row * rows_per_image;
1267
1268 if (packing->Invert) {
1269 /* set pixel_addr to the last row */
1270 topOfImage = bytes_per_row * (height - 1);
1271 bytes_per_row = -bytes_per_row;
1272 }
1273 else {
1274 topOfImage = 0;
1275 }
1276
1277 /* compute final pixel address */
1278 pixel_addr = (GLubyte *) image
1279 + (skipimages + img) * bytes_per_image
1280 + topOfImage
1281 + (skiprows + row) * bytes_per_row
1282 + (skippixels + column) * bytes_per_pixel;
1283 }
1284
1285 return (GLvoid *) pixel_addr;
1286 }
1287
1288
1289 GLvoid *
1290 _mesa_image_address1d( const struct gl_pixelstore_attrib *packing,
1291 const GLvoid *image,
1292 GLsizei width,
1293 GLenum format, GLenum type,
1294 GLint column )
1295 {
1296 return _mesa_image_address(1, packing, image, width, 1,
1297 format, type, 0, 0, column);
1298 }
1299
1300
1301 GLvoid *
1302 _mesa_image_address2d( const struct gl_pixelstore_attrib *packing,
1303 const GLvoid *image,
1304 GLsizei width, GLsizei height,
1305 GLenum format, GLenum type,
1306 GLint row, GLint column )
1307 {
1308 return _mesa_image_address(2, packing, image, width, height,
1309 format, type, 0, row, column);
1310 }
1311
1312
1313 GLvoid *
1314 _mesa_image_address3d( const struct gl_pixelstore_attrib *packing,
1315 const GLvoid *image,
1316 GLsizei width, GLsizei height,
1317 GLenum format, GLenum type,
1318 GLint img, GLint row, GLint column )
1319 {
1320 return _mesa_image_address(3, packing, image, width, height,
1321 format, type, img, row, column);
1322 }
1323
1324
1325
1326 /**
1327 * Compute the stride (in bytes) between image rows.
1328 *
1329 * \param packing the pixelstore attributes
1330 * \param width image width.
1331 * \param format pixel format.
1332 * \param type pixel data type.
1333 *
1334 * \return the stride in bytes for the given parameters, or -1 if error
1335 */
1336 GLint
1337 _mesa_image_row_stride( const struct gl_pixelstore_attrib *packing,
1338 GLint width, GLenum format, GLenum type )
1339 {
1340 GLint bytesPerRow, remainder;
1341
1342 ASSERT(packing);
1343
1344 if (type == GL_BITMAP) {
1345 if (packing->RowLength == 0) {
1346 bytesPerRow = (width + 7) / 8;
1347 }
1348 else {
1349 bytesPerRow = (packing->RowLength + 7) / 8;
1350 }
1351 }
1352 else {
1353 /* Non-BITMAP data */
1354 const GLint bytesPerPixel = _mesa_bytes_per_pixel(format, type);
1355 if (bytesPerPixel <= 0)
1356 return -1; /* error */
1357 if (packing->RowLength == 0) {
1358 bytesPerRow = bytesPerPixel * width;
1359 }
1360 else {
1361 bytesPerRow = bytesPerPixel * packing->RowLength;
1362 }
1363 }
1364
1365 remainder = bytesPerRow % packing->Alignment;
1366 if (remainder > 0) {
1367 bytesPerRow += (packing->Alignment - remainder);
1368 }
1369
1370 if (packing->Invert) {
1371 /* negate the bytes per row (negative row stride) */
1372 bytesPerRow = -bytesPerRow;
1373 }
1374
1375 return bytesPerRow;
1376 }
1377
1378
1379 /*
1380 * Compute the stride between images in a 3D texture (in bytes) for the given
1381 * pixel packing parameters and image width, format and type.
1382 */
1383 GLint
1384 _mesa_image_image_stride( const struct gl_pixelstore_attrib *packing,
1385 GLint width, GLint height,
1386 GLenum format, GLenum type )
1387 {
1388 GLint bytesPerRow, bytesPerImage, remainder;
1389
1390 ASSERT(packing);
1391
1392 if (type == GL_BITMAP) {
1393 if (packing->RowLength == 0) {
1394 bytesPerRow = (width + 7) / 8;
1395 }
1396 else {
1397 bytesPerRow = (packing->RowLength + 7) / 8;
1398 }
1399 }
1400 else {
1401 const GLint bytesPerPixel = _mesa_bytes_per_pixel(format, type);
1402
1403 if (bytesPerPixel <= 0)
1404 return -1; /* error */
1405 if (packing->RowLength == 0) {
1406 bytesPerRow = bytesPerPixel * width;
1407 }
1408 else {
1409 bytesPerRow = bytesPerPixel * packing->RowLength;
1410 }
1411 }
1412
1413 remainder = bytesPerRow % packing->Alignment;
1414 if (remainder > 0)
1415 bytesPerRow += (packing->Alignment - remainder);
1416
1417 if (packing->ImageHeight == 0)
1418 bytesPerImage = bytesPerRow * height;
1419 else
1420 bytesPerImage = bytesPerRow * packing->ImageHeight;
1421
1422 return bytesPerImage;
1423 }
1424
1425
1426
1427 /**
1428 * "Expand" a bitmap from 1-bit per pixel to 8-bits per pixel.
1429 * This is typically used to convert a bitmap into a GLubyte/pixel texture.
1430 * "On" bits will set texels to \p onValue.
1431 * "Off" bits will not modify texels.
1432 * \param width src bitmap width in pixels
1433 * \param height src bitmap height in pixels
1434 * \param unpack bitmap unpacking state
1435 * \param bitmap the src bitmap data
1436 * \param destBuffer start of dest buffer
1437 * \param destStride row stride in dest buffer
1438 * \param onValue if bit is 1, set destBuffer pixel to this value
1439 */
1440 void
1441 _mesa_expand_bitmap(GLsizei width, GLsizei height,
1442 const struct gl_pixelstore_attrib *unpack,
1443 const GLubyte *bitmap,
1444 GLubyte *destBuffer, GLint destStride,
1445 GLubyte onValue)
1446 {
1447 const GLubyte *srcRow = (const GLubyte *)
1448 _mesa_image_address2d(unpack, bitmap, width, height,
1449 GL_COLOR_INDEX, GL_BITMAP, 0, 0);
1450 const GLint srcStride = _mesa_image_row_stride(unpack, width,
1451 GL_COLOR_INDEX, GL_BITMAP);
1452 GLint row, col;
1453
1454 #define SET_PIXEL(COL, ROW) \
1455 destBuffer[(ROW) * destStride + (COL)] = onValue;
1456
1457 for (row = 0; row < height; row++) {
1458 const GLubyte *src = srcRow;
1459
1460 if (unpack->LsbFirst) {
1461 /* Lsb first */
1462 GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
1463 for (col = 0; col < width; col++) {
1464
1465 if (*src & mask) {
1466 SET_PIXEL(col, row);
1467 }
1468
1469 if (mask == 128U) {
1470 src++;
1471 mask = 1U;
1472 }
1473 else {
1474 mask = mask << 1;
1475 }
1476 }
1477
1478 /* get ready for next row */
1479 if (mask != 1)
1480 src++;
1481 }
1482 else {
1483 /* Msb first */
1484 GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
1485 for (col = 0; col < width; col++) {
1486
1487 if (*src & mask) {
1488 SET_PIXEL(col, row);
1489 }
1490
1491 if (mask == 1U) {
1492 src++;
1493 mask = 128U;
1494 }
1495 else {
1496 mask = mask >> 1;
1497 }
1498 }
1499
1500 /* get ready for next row */
1501 if (mask != 128)
1502 src++;
1503 }
1504
1505 srcRow += srcStride;
1506 } /* row */
1507
1508 #undef SET_PIXEL
1509 }
1510
1511
1512
1513
1514 /**
1515 * Convert an array of RGBA colors from one datatype to another.
1516 * NOTE: src may equal dst. In that case, we use a temporary buffer.
1517 */
1518 void
1519 _mesa_convert_colors(GLenum srcType, const GLvoid *src,
1520 GLenum dstType, GLvoid *dst,
1521 GLuint count, const GLubyte mask[])
1522 {
1523 GLuint tempBuffer[MAX_WIDTH][4];
1524 const GLboolean useTemp = (src == dst);
1525
1526 ASSERT(srcType != dstType);
1527
1528 switch (srcType) {
1529 case GL_UNSIGNED_BYTE:
1530 if (dstType == GL_UNSIGNED_SHORT) {
1531 const GLubyte (*src1)[4] = (const GLubyte (*)[4]) src;
1532 GLushort (*dst2)[4] = (GLushort (*)[4]) (useTemp ? tempBuffer : dst);
1533 GLuint i;
1534 for (i = 0; i < count; i++) {
1535 if (!mask || mask[i]) {
1536 dst2[i][RCOMP] = UBYTE_TO_USHORT(src1[i][RCOMP]);
1537 dst2[i][GCOMP] = UBYTE_TO_USHORT(src1[i][GCOMP]);
1538 dst2[i][BCOMP] = UBYTE_TO_USHORT(src1[i][BCOMP]);
1539 dst2[i][ACOMP] = UBYTE_TO_USHORT(src1[i][ACOMP]);
1540 }
1541 }
1542 if (useTemp)
1543 memcpy(dst, tempBuffer, count * 4 * sizeof(GLushort));
1544 }
1545 else {
1546 const GLubyte (*src1)[4] = (const GLubyte (*)[4]) src;
1547 GLfloat (*dst4)[4] = (GLfloat (*)[4]) (useTemp ? tempBuffer : dst);
1548 GLuint i;
1549 ASSERT(dstType == GL_FLOAT);
1550 for (i = 0; i < count; i++) {
1551 if (!mask || mask[i]) {
1552 dst4[i][RCOMP] = UBYTE_TO_FLOAT(src1[i][RCOMP]);
1553 dst4[i][GCOMP] = UBYTE_TO_FLOAT(src1[i][GCOMP]);
1554 dst4[i][BCOMP] = UBYTE_TO_FLOAT(src1[i][BCOMP]);
1555 dst4[i][ACOMP] = UBYTE_TO_FLOAT(src1[i][ACOMP]);
1556 }
1557 }
1558 if (useTemp)
1559 memcpy(dst, tempBuffer, count * 4 * sizeof(GLfloat));
1560 }
1561 break;
1562 case GL_UNSIGNED_SHORT:
1563 if (dstType == GL_UNSIGNED_BYTE) {
1564 const GLushort (*src2)[4] = (const GLushort (*)[4]) src;
1565 GLubyte (*dst1)[4] = (GLubyte (*)[4]) (useTemp ? tempBuffer : dst);
1566 GLuint i;
1567 for (i = 0; i < count; i++) {
1568 if (!mask || mask[i]) {
1569 dst1[i][RCOMP] = USHORT_TO_UBYTE(src2[i][RCOMP]);
1570 dst1[i][GCOMP] = USHORT_TO_UBYTE(src2[i][GCOMP]);
1571 dst1[i][BCOMP] = USHORT_TO_UBYTE(src2[i][BCOMP]);
1572 dst1[i][ACOMP] = USHORT_TO_UBYTE(src2[i][ACOMP]);
1573 }
1574 }
1575 if (useTemp)
1576 memcpy(dst, tempBuffer, count * 4 * sizeof(GLubyte));
1577 }
1578 else {
1579 const GLushort (*src2)[4] = (const GLushort (*)[4]) src;
1580 GLfloat (*dst4)[4] = (GLfloat (*)[4]) (useTemp ? tempBuffer : dst);
1581 GLuint i;
1582 ASSERT(dstType == GL_FLOAT);
1583 for (i = 0; i < count; i++) {
1584 if (!mask || mask[i]) {
1585 dst4[i][RCOMP] = USHORT_TO_FLOAT(src2[i][RCOMP]);
1586 dst4[i][GCOMP] = USHORT_TO_FLOAT(src2[i][GCOMP]);
1587 dst4[i][BCOMP] = USHORT_TO_FLOAT(src2[i][BCOMP]);
1588 dst4[i][ACOMP] = USHORT_TO_FLOAT(src2[i][ACOMP]);
1589 }
1590 }
1591 if (useTemp)
1592 memcpy(dst, tempBuffer, count * 4 * sizeof(GLfloat));
1593 }
1594 break;
1595 case GL_FLOAT:
1596 if (dstType == GL_UNSIGNED_BYTE) {
1597 const GLfloat (*src4)[4] = (const GLfloat (*)[4]) src;
1598 GLubyte (*dst1)[4] = (GLubyte (*)[4]) (useTemp ? tempBuffer : dst);
1599 GLuint i;
1600 for (i = 0; i < count; i++) {
1601 if (!mask || mask[i])
1602 _mesa_unclamped_float_rgba_to_ubyte(dst1[i], src4[i]);
1603 }
1604 if (useTemp)
1605 memcpy(dst, tempBuffer, count * 4 * sizeof(GLubyte));
1606 }
1607 else {
1608 const GLfloat (*src4)[4] = (const GLfloat (*)[4]) src;
1609 GLushort (*dst2)[4] = (GLushort (*)[4]) (useTemp ? tempBuffer : dst);
1610 GLuint i;
1611 ASSERT(dstType == GL_UNSIGNED_SHORT);
1612 for (i = 0; i < count; i++) {
1613 if (!mask || mask[i]) {
1614 UNCLAMPED_FLOAT_TO_USHORT(dst2[i][RCOMP], src4[i][RCOMP]);
1615 UNCLAMPED_FLOAT_TO_USHORT(dst2[i][GCOMP], src4[i][GCOMP]);
1616 UNCLAMPED_FLOAT_TO_USHORT(dst2[i][BCOMP], src4[i][BCOMP]);
1617 UNCLAMPED_FLOAT_TO_USHORT(dst2[i][ACOMP], src4[i][ACOMP]);
1618 }
1619 }
1620 if (useTemp)
1621 memcpy(dst, tempBuffer, count * 4 * sizeof(GLushort));
1622 }
1623 break;
1624 default:
1625 _mesa_problem(NULL, "Invalid datatype in _mesa_convert_colors");
1626 }
1627 }
1628
1629
1630
1631
1632 /**
1633 * Perform basic clipping for glDrawPixels. The image's position and size
1634 * and the unpack SkipPixels and SkipRows are adjusted so that the image
1635 * region is entirely within the window and scissor bounds.
1636 * NOTE: this will only work when glPixelZoom is (1, 1) or (1, -1).
1637 * If Pixel.ZoomY is -1, *destY will be changed to be the first row which
1638 * we'll actually write. Beforehand, *destY-1 is the first drawing row.
1639 *
1640 * \return GL_TRUE if image is ready for drawing or
1641 * GL_FALSE if image was completely clipped away (draw nothing)
1642 */
1643 GLboolean
1644 _mesa_clip_drawpixels(const struct gl_context *ctx,
1645 GLint *destX, GLint *destY,
1646 GLsizei *width, GLsizei *height,
1647 struct gl_pixelstore_attrib *unpack)
1648 {
1649 const struct gl_framebuffer *buffer = ctx->DrawBuffer;
1650
1651 if (unpack->RowLength == 0) {
1652 unpack->RowLength = *width;
1653 }
1654
1655 ASSERT(ctx->Pixel.ZoomX == 1.0F);
1656 ASSERT(ctx->Pixel.ZoomY == 1.0F || ctx->Pixel.ZoomY == -1.0F);
1657
1658 /* left clipping */
1659 if (*destX < buffer->_Xmin) {
1660 unpack->SkipPixels += (buffer->_Xmin - *destX);
1661 *width -= (buffer->_Xmin - *destX);
1662 *destX = buffer->_Xmin;
1663 }
1664 /* right clipping */
1665 if (*destX + *width > buffer->_Xmax)
1666 *width -= (*destX + *width - buffer->_Xmax);
1667
1668 if (*width <= 0)
1669 return GL_FALSE;
1670
1671 if (ctx->Pixel.ZoomY == 1.0F) {
1672 /* bottom clipping */
1673 if (*destY < buffer->_Ymin) {
1674 unpack->SkipRows += (buffer->_Ymin - *destY);
1675 *height -= (buffer->_Ymin - *destY);
1676 *destY = buffer->_Ymin;
1677 }
1678 /* top clipping */
1679 if (*destY + *height > buffer->_Ymax)
1680 *height -= (*destY + *height - buffer->_Ymax);
1681 }
1682 else { /* upside down */
1683 /* top clipping */
1684 if (*destY > buffer->_Ymax) {
1685 unpack->SkipRows += (*destY - buffer->_Ymax);
1686 *height -= (*destY - buffer->_Ymax);
1687 *destY = buffer->_Ymax;
1688 }
1689 /* bottom clipping */
1690 if (*destY - *height < buffer->_Ymin)
1691 *height -= (buffer->_Ymin - (*destY - *height));
1692 /* adjust destY so it's the first row to write to */
1693 (*destY)--;
1694 }
1695
1696 if (*height <= 0)
1697 return GL_FALSE;
1698
1699 return GL_TRUE;
1700 }
1701
1702
1703 /**
1704 * Perform clipping for glReadPixels. The image's window position
1705 * and size, and the pack skipPixels, skipRows and rowLength are adjusted
1706 * so that the image region is entirely within the window bounds.
1707 * Note: this is different from _mesa_clip_drawpixels() in that the
1708 * scissor box is ignored, and we use the bounds of the current readbuffer
1709 * surface.
1710 *
1711 * \return GL_TRUE if region to read is in bounds
1712 * GL_FALSE if region is completely out of bounds (nothing to read)
1713 */
1714 GLboolean
1715 _mesa_clip_readpixels(const struct gl_context *ctx,
1716 GLint *srcX, GLint *srcY,
1717 GLsizei *width, GLsizei *height,
1718 struct gl_pixelstore_attrib *pack)
1719 {
1720 const struct gl_framebuffer *buffer = ctx->ReadBuffer;
1721
1722 if (pack->RowLength == 0) {
1723 pack->RowLength = *width;
1724 }
1725
1726 /* left clipping */
1727 if (*srcX < 0) {
1728 pack->SkipPixels += (0 - *srcX);
1729 *width -= (0 - *srcX);
1730 *srcX = 0;
1731 }
1732 /* right clipping */
1733 if (*srcX + *width > (GLsizei) buffer->Width)
1734 *width -= (*srcX + *width - buffer->Width);
1735
1736 if (*width <= 0)
1737 return GL_FALSE;
1738
1739 /* bottom clipping */
1740 if (*srcY < 0) {
1741 pack->SkipRows += (0 - *srcY);
1742 *height -= (0 - *srcY);
1743 *srcY = 0;
1744 }
1745 /* top clipping */
1746 if (*srcY + *height > (GLsizei) buffer->Height)
1747 *height -= (*srcY + *height - buffer->Height);
1748
1749 if (*height <= 0)
1750 return GL_FALSE;
1751
1752 return GL_TRUE;
1753 }
1754
1755
1756 /**
1757 * Do clipping for a glCopyTexSubImage call.
1758 * The framebuffer source region might extend outside the framebuffer
1759 * bounds. Clip the source region against the framebuffer bounds and
1760 * adjust the texture/dest position and size accordingly.
1761 *
1762 * \return GL_FALSE if region is totally clipped, GL_TRUE otherwise.
1763 */
1764 GLboolean
1765 _mesa_clip_copytexsubimage(const struct gl_context *ctx,
1766 GLint *destX, GLint *destY,
1767 GLint *srcX, GLint *srcY,
1768 GLsizei *width, GLsizei *height)
1769 {
1770 const struct gl_framebuffer *fb = ctx->ReadBuffer;
1771 const GLint srcX0 = *srcX, srcY0 = *srcY;
1772
1773 if (_mesa_clip_to_region(0, 0, fb->Width, fb->Height,
1774 srcX, srcY, width, height)) {
1775 *destX = *destX + *srcX - srcX0;
1776 *destY = *destY + *srcY - srcY0;
1777
1778 return GL_TRUE;
1779 }
1780 else {
1781 return GL_FALSE;
1782 }
1783 }
1784
1785
1786
1787 /**
1788 * Clip the rectangle defined by (x, y, width, height) against the bounds
1789 * specified by [xmin, xmax) and [ymin, ymax).
1790 * \return GL_FALSE if rect is totally clipped, GL_TRUE otherwise.
1791 */
1792 GLboolean
1793 _mesa_clip_to_region(GLint xmin, GLint ymin,
1794 GLint xmax, GLint ymax,
1795 GLint *x, GLint *y,
1796 GLsizei *width, GLsizei *height )
1797 {
1798 /* left clipping */
1799 if (*x < xmin) {
1800 *width -= (xmin - *x);
1801 *x = xmin;
1802 }
1803
1804 /* right clipping */
1805 if (*x + *width > xmax)
1806 *width -= (*x + *width - xmax);
1807
1808 if (*width <= 0)
1809 return GL_FALSE;
1810
1811 /* bottom (or top) clipping */
1812 if (*y < ymin) {
1813 *height -= (ymin - *y);
1814 *y = ymin;
1815 }
1816
1817 /* top (or bottom) clipping */
1818 if (*y + *height > ymax)
1819 *height -= (*y + *height - ymax);
1820
1821 if (*height <= 0)
1822 return GL_FALSE;
1823
1824 return GL_TRUE;
1825 }
1826
1827
1828 /**
1829 * Clip dst coords against Xmax (or Ymax).
1830 */
1831 static inline void
1832 clip_right_or_top(GLint *srcX0, GLint *srcX1,
1833 GLint *dstX0, GLint *dstX1,
1834 GLint maxValue)
1835 {
1836 GLfloat t, bias;
1837
1838 if (*dstX1 > maxValue) {
1839 /* X1 outside right edge */
1840 ASSERT(*dstX0 < maxValue); /* X0 should be inside right edge */
1841 t = (GLfloat) (maxValue - *dstX0) / (GLfloat) (*dstX1 - *dstX0);
1842 /* chop off [t, 1] part */
1843 ASSERT(t >= 0.0 && t <= 1.0);
1844 *dstX1 = maxValue;
1845 bias = (*srcX0 < *srcX1) ? 0.5F : -0.5F;
1846 *srcX1 = *srcX0 + (GLint) (t * (*srcX1 - *srcX0) + bias);
1847 }
1848 else if (*dstX0 > maxValue) {
1849 /* X0 outside right edge */
1850 ASSERT(*dstX1 < maxValue); /* X1 should be inside right edge */
1851 t = (GLfloat) (maxValue - *dstX1) / (GLfloat) (*dstX0 - *dstX1);
1852 /* chop off [t, 1] part */
1853 ASSERT(t >= 0.0 && t <= 1.0);
1854 *dstX0 = maxValue;
1855 bias = (*srcX0 < *srcX1) ? -0.5F : 0.5F;
1856 *srcX0 = *srcX1 + (GLint) (t * (*srcX0 - *srcX1) + bias);
1857 }
1858 }
1859
1860
1861 /**
1862 * Clip dst coords against Xmin (or Ymin).
1863 */
1864 static inline void
1865 clip_left_or_bottom(GLint *srcX0, GLint *srcX1,
1866 GLint *dstX0, GLint *dstX1,
1867 GLint minValue)
1868 {
1869 GLfloat t, bias;
1870
1871 if (*dstX0 < minValue) {
1872 /* X0 outside left edge */
1873 ASSERT(*dstX1 > minValue); /* X1 should be inside left edge */
1874 t = (GLfloat) (minValue - *dstX0) / (GLfloat) (*dstX1 - *dstX0);
1875 /* chop off [0, t] part */
1876 ASSERT(t >= 0.0 && t <= 1.0);
1877 *dstX0 = minValue;
1878 bias = (*srcX0 < *srcX1) ? 0.5F : -0.5F; /* flipped??? */
1879 *srcX0 = *srcX0 + (GLint) (t * (*srcX1 - *srcX0) + bias);
1880 }
1881 else if (*dstX1 < minValue) {
1882 /* X1 outside left edge */
1883 ASSERT(*dstX0 > minValue); /* X0 should be inside left edge */
1884 t = (GLfloat) (minValue - *dstX1) / (GLfloat) (*dstX0 - *dstX1);
1885 /* chop off [0, t] part */
1886 ASSERT(t >= 0.0 && t <= 1.0);
1887 *dstX1 = minValue;
1888 bias = (*srcX0 < *srcX1) ? 0.5F : -0.5F;
1889 *srcX1 = *srcX1 + (GLint) (t * (*srcX0 - *srcX1) + bias);
1890 }
1891 }
1892
1893
1894 /**
1895 * Do clipping of blit src/dest rectangles.
1896 * The dest rect is clipped against both the buffer bounds and scissor bounds.
1897 * The src rect is just clipped against the buffer bounds.
1898 *
1899 * When either the src or dest rect is clipped, the other is also clipped
1900 * proportionately!
1901 *
1902 * Note that X0 need not be less than X1 (same for Y) for either the source
1903 * and dest rects. That makes the clipping a little trickier.
1904 *
1905 * \return GL_TRUE if anything is left to draw, GL_FALSE if totally clipped
1906 */
1907 GLboolean
1908 _mesa_clip_blit(struct gl_context *ctx,
1909 GLint *srcX0, GLint *srcY0, GLint *srcX1, GLint *srcY1,
1910 GLint *dstX0, GLint *dstY0, GLint *dstX1, GLint *dstY1)
1911 {
1912 const GLint srcXmin = 0;
1913 const GLint srcXmax = ctx->ReadBuffer->Width;
1914 const GLint srcYmin = 0;
1915 const GLint srcYmax = ctx->ReadBuffer->Height;
1916
1917 /* these include scissor bounds */
1918 const GLint dstXmin = ctx->DrawBuffer->_Xmin;
1919 const GLint dstXmax = ctx->DrawBuffer->_Xmax;
1920 const GLint dstYmin = ctx->DrawBuffer->_Ymin;
1921 const GLint dstYmax = ctx->DrawBuffer->_Ymax;
1922
1923 /*
1924 printf("PreClipX: src: %d .. %d dst: %d .. %d\n",
1925 *srcX0, *srcX1, *dstX0, *dstX1);
1926 printf("PreClipY: src: %d .. %d dst: %d .. %d\n",
1927 *srcY0, *srcY1, *dstY0, *dstY1);
1928 */
1929
1930 /* trivial rejection tests */
1931 if (*dstX0 == *dstX1)
1932 return GL_FALSE; /* no width */
1933 if (*dstX0 <= dstXmin && *dstX1 <= dstXmin)
1934 return GL_FALSE; /* totally out (left) of bounds */
1935 if (*dstX0 >= dstXmax && *dstX1 >= dstXmax)
1936 return GL_FALSE; /* totally out (right) of bounds */
1937
1938 if (*dstY0 == *dstY1)
1939 return GL_FALSE;
1940 if (*dstY0 <= dstYmin && *dstY1 <= dstYmin)
1941 return GL_FALSE;
1942 if (*dstY0 >= dstYmax && *dstY1 >= dstYmax)
1943 return GL_FALSE;
1944
1945 if (*srcX0 == *srcX1)
1946 return GL_FALSE;
1947 if (*srcX0 <= srcXmin && *srcX1 <= srcXmin)
1948 return GL_FALSE;
1949 if (*srcX0 >= srcXmax && *srcX1 >= srcXmax)
1950 return GL_FALSE;
1951
1952 if (*srcY0 == *srcY1)
1953 return GL_FALSE;
1954 if (*srcY0 <= srcYmin && *srcY1 <= srcYmin)
1955 return GL_FALSE;
1956 if (*srcY0 >= srcYmax && *srcY1 >= srcYmax)
1957 return GL_FALSE;
1958
1959 /*
1960 * dest clip
1961 */
1962 clip_right_or_top(srcX0, srcX1, dstX0, dstX1, dstXmax);
1963 clip_right_or_top(srcY0, srcY1, dstY0, dstY1, dstYmax);
1964 clip_left_or_bottom(srcX0, srcX1, dstX0, dstX1, dstXmin);
1965 clip_left_or_bottom(srcY0, srcY1, dstY0, dstY1, dstYmin);
1966
1967 /*
1968 * src clip (just swap src/dst values from above)
1969 */
1970 clip_right_or_top(dstX0, dstX1, srcX0, srcX1, srcXmax);
1971 clip_right_or_top(dstY0, dstY1, srcY0, srcY1, srcYmax);
1972 clip_left_or_bottom(dstX0, dstX1, srcX0, srcX1, srcXmin);
1973 clip_left_or_bottom(dstY0, dstY1, srcY0, srcY1, srcYmin);
1974
1975 /*
1976 printf("PostClipX: src: %d .. %d dst: %d .. %d\n",
1977 *srcX0, *srcX1, *dstX0, *dstX1);
1978 printf("PostClipY: src: %d .. %d dst: %d .. %d\n",
1979 *srcY0, *srcY1, *dstY0, *dstY1);
1980 */
1981
1982 ASSERT(*dstX0 >= dstXmin);
1983 ASSERT(*dstX0 <= dstXmax);
1984 ASSERT(*dstX1 >= dstXmin);
1985 ASSERT(*dstX1 <= dstXmax);
1986
1987 ASSERT(*dstY0 >= dstYmin);
1988 ASSERT(*dstY0 <= dstYmax);
1989 ASSERT(*dstY1 >= dstYmin);
1990 ASSERT(*dstY1 <= dstYmax);
1991
1992 ASSERT(*srcX0 >= srcXmin);
1993 ASSERT(*srcX0 <= srcXmax);
1994 ASSERT(*srcX1 >= srcXmin);
1995 ASSERT(*srcX1 <= srcXmax);
1996
1997 ASSERT(*srcY0 >= srcYmin);
1998 ASSERT(*srcY0 <= srcYmax);
1999 ASSERT(*srcY1 >= srcYmin);
2000 ASSERT(*srcY1 <= srcYmax);
2001
2002 return GL_TRUE;
2003 }