image.c revision 923f143335ad1cba4795276e79cb1a5b0cd19bbc 
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 */
46GLboolean
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 */
83void
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 */
97void
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 */
120GLint
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 */
156GLint
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 */
214GLint
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	 return 3;
247
248      case GL_RGBA:
249      case GL_BGRA:
250      case GL_ABGR_EXT:
251      case GL_RGBA_INTEGER_EXT:
252         return 4;
253
254      default:
255         return -1;
256   }
257}
258
259
260/**
261 * Get the bytes per pixel of pixel format type pair.
262 *
263 * \param format pixel format.
264 * \param type pixel type.
265 *
266 * \return bytes per pixel, or -1 if a bad format or type was given.
267 */
268GLint
269_mesa_bytes_per_pixel( GLenum format, GLenum type )
270{
271   GLint comps = _mesa_components_in_format( format );
272   if (comps < 0)
273      return -1;
274
275   switch (type) {
276      case GL_BITMAP:
277         return 0;  /* special case */
278      case GL_BYTE:
279      case GL_UNSIGNED_BYTE:
280         return comps * sizeof(GLubyte);
281      case GL_SHORT:
282      case GL_UNSIGNED_SHORT:
283         return comps * sizeof(GLshort);
284      case GL_INT:
285      case GL_UNSIGNED_INT:
286         return comps * sizeof(GLint);
287      case GL_FLOAT:
288         return comps * sizeof(GLfloat);
289      case GL_HALF_FLOAT_ARB:
290         return comps * sizeof(GLhalfARB);
291      case GL_UNSIGNED_BYTE_3_3_2:
292      case GL_UNSIGNED_BYTE_2_3_3_REV:
293         if (format == GL_RGB || format == GL_BGR ||
294             format == GL_RGB_INTEGER_EXT || format == GL_BGR_INTEGER_EXT)
295            return sizeof(GLubyte);
296         else
297            return -1;  /* error */
298      case GL_UNSIGNED_SHORT_5_6_5:
299      case GL_UNSIGNED_SHORT_5_6_5_REV:
300         if (format == GL_RGB || format == GL_BGR ||
301             format == GL_RGB_INTEGER_EXT || format == GL_BGR_INTEGER_EXT)
302            return sizeof(GLushort);
303         else
304            return -1;  /* error */
305      case GL_UNSIGNED_SHORT_4_4_4_4:
306      case GL_UNSIGNED_SHORT_4_4_4_4_REV:
307      case GL_UNSIGNED_SHORT_5_5_5_1:
308      case GL_UNSIGNED_SHORT_1_5_5_5_REV:
309         if (format == GL_RGBA || format == GL_BGRA || format == GL_ABGR_EXT ||
310             format == GL_RGBA_INTEGER_EXT || format == GL_BGRA_INTEGER_EXT)
311            return sizeof(GLushort);
312         else
313            return -1;
314      case GL_UNSIGNED_INT_8_8_8_8:
315      case GL_UNSIGNED_INT_8_8_8_8_REV:
316      case GL_UNSIGNED_INT_10_10_10_2:
317      case GL_UNSIGNED_INT_2_10_10_10_REV:
318         if (format == GL_RGBA || format == GL_BGRA || format == GL_ABGR_EXT ||
319             format == GL_RGBA_INTEGER_EXT || format == GL_BGRA_INTEGER_EXT)
320            return sizeof(GLuint);
321         else
322            return -1;
323      case GL_UNSIGNED_SHORT_8_8_MESA:
324      case GL_UNSIGNED_SHORT_8_8_REV_MESA:
325         if (format == GL_YCBCR_MESA)
326            return sizeof(GLushort);
327         else
328            return -1;
329      case GL_UNSIGNED_INT_24_8_EXT:
330         if (format == GL_DEPTH_STENCIL_EXT)
331            return sizeof(GLuint);
332         else
333            return -1;
334      case GL_UNSIGNED_INT_5_9_9_9_REV:
335         if (format == GL_RGB)
336            return sizeof(GLuint);
337         else
338            return -1;
339      case GL_UNSIGNED_INT_10F_11F_11F_REV:
340         if (format == GL_RGB)
341            return sizeof(GLuint);
342         else
343            return -1;
344      case GL_FLOAT_32_UNSIGNED_INT_24_8_REV:
345         if (format == GL_DEPTH_STENCIL)
346            return 8;
347         else
348            return -1;
349      default:
350         return -1;
351   }
352}
353
354
355/**
356 * Test for a legal pixel format and type.
357 *
358 * \param format pixel format.
359 * \param type pixel type.
360 *
361 * \return GL_TRUE if the given pixel format and type are legal, or GL_FALSE
362 * otherwise.
363 */
364GLboolean
365_mesa_is_legal_format_and_type(const struct gl_context *ctx,
366                               GLenum format, GLenum type)
367{
368   switch (format) {
369      case GL_COLOR_INDEX:
370      case GL_STENCIL_INDEX:
371         switch (type) {
372            case GL_BITMAP:
373            case GL_BYTE:
374            case GL_UNSIGNED_BYTE:
375            case GL_SHORT:
376            case GL_UNSIGNED_SHORT:
377            case GL_INT:
378            case GL_UNSIGNED_INT:
379            case GL_FLOAT:
380               return GL_TRUE;
381            case GL_HALF_FLOAT_ARB:
382               return ctx->Extensions.ARB_half_float_pixel;
383            default:
384               return GL_FALSE;
385         }
386      case GL_RED:
387      case GL_GREEN:
388      case GL_BLUE:
389      case GL_ALPHA:
390#if 0 /* not legal!  see table 3.6 of the 1.5 spec */
391      case GL_INTENSITY:
392#endif
393      case GL_LUMINANCE:
394      case GL_LUMINANCE_ALPHA:
395      case GL_DEPTH_COMPONENT:
396         switch (type) {
397            case GL_BYTE:
398            case GL_UNSIGNED_BYTE:
399            case GL_SHORT:
400            case GL_UNSIGNED_SHORT:
401            case GL_INT:
402            case GL_UNSIGNED_INT:
403            case GL_FLOAT:
404               return GL_TRUE;
405            case GL_HALF_FLOAT_ARB:
406               return ctx->Extensions.ARB_half_float_pixel;
407            default:
408               return GL_FALSE;
409         }
410      case GL_RG:
411	 if (!ctx->Extensions.ARB_texture_rg)
412	    return GL_FALSE;
413
414         switch (type) {
415            case GL_BYTE:
416            case GL_UNSIGNED_BYTE:
417            case GL_SHORT:
418            case GL_UNSIGNED_SHORT:
419            case GL_INT:
420            case GL_UNSIGNED_INT:
421            case GL_FLOAT:
422               return GL_TRUE;
423            case GL_HALF_FLOAT_ARB:
424               return ctx->Extensions.ARB_half_float_pixel;
425            default:
426               return GL_FALSE;
427         }
428      case GL_RGB:
429         switch (type) {
430            case GL_BYTE:
431            case GL_UNSIGNED_BYTE:
432            case GL_SHORT:
433            case GL_UNSIGNED_SHORT:
434            case GL_INT:
435            case GL_UNSIGNED_INT:
436            case GL_FLOAT:
437            case GL_UNSIGNED_BYTE_3_3_2:
438            case GL_UNSIGNED_BYTE_2_3_3_REV:
439            case GL_UNSIGNED_SHORT_5_6_5:
440            case GL_UNSIGNED_SHORT_5_6_5_REV:
441               return GL_TRUE;
442            case GL_HALF_FLOAT_ARB:
443               return ctx->Extensions.ARB_half_float_pixel;
444            case GL_UNSIGNED_INT_5_9_9_9_REV:
445               return ctx->Extensions.EXT_texture_shared_exponent;
446            case GL_UNSIGNED_INT_10F_11F_11F_REV:
447               return ctx->Extensions.EXT_packed_float;
448            default:
449               return GL_FALSE;
450         }
451      case GL_BGR:
452         switch (type) {
453            /* NOTE: no packed types are supported with BGR.  That's
454             * intentional, according to the GL spec.
455             */
456            case GL_BYTE:
457            case GL_UNSIGNED_BYTE:
458            case GL_SHORT:
459            case GL_UNSIGNED_SHORT:
460            case GL_INT:
461            case GL_UNSIGNED_INT:
462            case GL_FLOAT:
463               return GL_TRUE;
464            case GL_HALF_FLOAT_ARB:
465               return ctx->Extensions.ARB_half_float_pixel;
466            default:
467               return GL_FALSE;
468         }
469      case GL_RGBA:
470      case GL_BGRA:
471      case GL_ABGR_EXT:
472         switch (type) {
473            case GL_BYTE:
474            case GL_UNSIGNED_BYTE:
475            case GL_SHORT:
476            case GL_UNSIGNED_SHORT:
477            case GL_INT:
478            case GL_UNSIGNED_INT:
479            case GL_FLOAT:
480            case GL_UNSIGNED_SHORT_4_4_4_4:
481            case GL_UNSIGNED_SHORT_4_4_4_4_REV:
482            case GL_UNSIGNED_SHORT_5_5_5_1:
483            case GL_UNSIGNED_SHORT_1_5_5_5_REV:
484            case GL_UNSIGNED_INT_8_8_8_8:
485            case GL_UNSIGNED_INT_8_8_8_8_REV:
486            case GL_UNSIGNED_INT_10_10_10_2:
487            case GL_UNSIGNED_INT_2_10_10_10_REV:
488               return GL_TRUE;
489            case GL_HALF_FLOAT_ARB:
490               return ctx->Extensions.ARB_half_float_pixel;
491            default:
492               return GL_FALSE;
493         }
494      case GL_YCBCR_MESA:
495         if (type == GL_UNSIGNED_SHORT_8_8_MESA ||
496             type == GL_UNSIGNED_SHORT_8_8_REV_MESA)
497            return GL_TRUE;
498         else
499            return GL_FALSE;
500      case GL_DEPTH_STENCIL_EXT:
501         if ((ctx->Extensions.EXT_packed_depth_stencil &&
502              type == GL_UNSIGNED_INT_24_8_EXT) ||
503             (ctx->Extensions.ARB_depth_buffer_float &&
504              type == GL_FLOAT_32_UNSIGNED_INT_24_8_REV))
505            return GL_TRUE;
506         else
507            return GL_FALSE;
508      case GL_DUDV_ATI:
509      case GL_DU8DV8_ATI:
510         switch (type) {
511            case GL_BYTE:
512            case GL_UNSIGNED_BYTE:
513            case GL_SHORT:
514            case GL_UNSIGNED_SHORT:
515            case GL_INT:
516            case GL_UNSIGNED_INT:
517            case GL_FLOAT:
518               return GL_TRUE;
519            default:
520               return GL_FALSE;
521         }
522
523      /* integer-valued formats */
524      case GL_RED_INTEGER_EXT:
525      case GL_GREEN_INTEGER_EXT:
526      case GL_BLUE_INTEGER_EXT:
527      case GL_ALPHA_INTEGER_EXT:
528         switch (type) {
529            case GL_BYTE:
530            case GL_UNSIGNED_BYTE:
531            case GL_SHORT:
532            case GL_UNSIGNED_SHORT:
533            case GL_INT:
534            case GL_UNSIGNED_INT:
535               return ctx->Extensions.EXT_texture_integer;
536            default:
537               return GL_FALSE;
538         }
539
540      case GL_RGB_INTEGER_EXT:
541         switch (type) {
542            case GL_BYTE:
543            case GL_UNSIGNED_BYTE:
544            case GL_SHORT:
545            case GL_UNSIGNED_SHORT:
546            case GL_INT:
547            case GL_UNSIGNED_INT:
548               return ctx->Extensions.EXT_texture_integer;
549            case GL_UNSIGNED_BYTE_3_3_2:
550            case GL_UNSIGNED_BYTE_2_3_3_REV:
551            case GL_UNSIGNED_SHORT_5_6_5:
552            case GL_UNSIGNED_SHORT_5_6_5_REV:
553               return ctx->Extensions.ARB_texture_rgb10_a2ui;
554            default:
555               return GL_FALSE;
556         }
557
558      case GL_BGR_INTEGER_EXT:
559         switch (type) {
560            case GL_BYTE:
561            case GL_UNSIGNED_BYTE:
562            case GL_SHORT:
563            case GL_UNSIGNED_SHORT:
564            case GL_INT:
565            case GL_UNSIGNED_INT:
566            /* NOTE: no packed formats w/ BGR format */
567               return ctx->Extensions.EXT_texture_integer;
568            default:
569               return GL_FALSE;
570         }
571
572      case GL_RGBA_INTEGER_EXT:
573      case GL_BGRA_INTEGER_EXT:
574         switch (type) {
575            case GL_BYTE:
576            case GL_UNSIGNED_BYTE:
577            case GL_SHORT:
578            case GL_UNSIGNED_SHORT:
579            case GL_INT:
580            case GL_UNSIGNED_INT:
581               return ctx->Extensions.EXT_texture_integer;
582            case GL_UNSIGNED_SHORT_4_4_4_4:
583            case GL_UNSIGNED_SHORT_4_4_4_4_REV:
584            case GL_UNSIGNED_SHORT_5_5_5_1:
585            case GL_UNSIGNED_SHORT_1_5_5_5_REV:
586            case GL_UNSIGNED_INT_8_8_8_8:
587            case GL_UNSIGNED_INT_8_8_8_8_REV:
588            case GL_UNSIGNED_INT_10_10_10_2:
589            case GL_UNSIGNED_INT_2_10_10_10_REV:
590               return ctx->Extensions.ARB_texture_rgb10_a2ui;
591            default:
592               return GL_FALSE;
593         }
594
595      case GL_LUMINANCE_INTEGER_EXT:
596      case GL_LUMINANCE_ALPHA_INTEGER_EXT:
597         switch (type) {
598            case GL_BYTE:
599            case GL_UNSIGNED_BYTE:
600            case GL_SHORT:
601            case GL_UNSIGNED_SHORT:
602            case GL_INT:
603            case GL_UNSIGNED_INT:
604               return ctx->Extensions.EXT_texture_integer;
605            default:
606               return GL_FALSE;
607         }
608
609      default:
610         ; /* fall-through */
611   }
612   return GL_FALSE;
613}
614
615
616/**
617 * Test if the given image format is a color/RGBA format (i.e., not color
618 * index, depth, stencil, etc).
619 * \param format  the image format value (may by an internal texture format)
620 * \return GL_TRUE if its a color/RGBA format, GL_FALSE otherwise.
621 */
622GLboolean
623_mesa_is_color_format(GLenum format)
624{
625   switch (format) {
626      case GL_RED:
627      case GL_GREEN:
628      case GL_BLUE:
629      case GL_ALPHA:
630      case GL_ALPHA4:
631      case GL_ALPHA8:
632      case GL_ALPHA12:
633      case GL_ALPHA16:
634      case 1:
635      case GL_LUMINANCE:
636      case GL_LUMINANCE4:
637      case GL_LUMINANCE8:
638      case GL_LUMINANCE12:
639      case GL_LUMINANCE16:
640      case 2:
641      case GL_LUMINANCE_ALPHA:
642      case GL_LUMINANCE4_ALPHA4:
643      case GL_LUMINANCE6_ALPHA2:
644      case GL_LUMINANCE8_ALPHA8:
645      case GL_LUMINANCE12_ALPHA4:
646      case GL_LUMINANCE12_ALPHA12:
647      case GL_LUMINANCE16_ALPHA16:
648      case GL_INTENSITY:
649      case GL_INTENSITY4:
650      case GL_INTENSITY8:
651      case GL_INTENSITY12:
652      case GL_INTENSITY16:
653      case GL_R8:
654      case GL_R16:
655      case GL_RG:
656      case GL_RG8:
657      case GL_RG16:
658      case 3:
659      case GL_RGB:
660      case GL_BGR:
661      case GL_R3_G3_B2:
662      case GL_RGB4:
663      case GL_RGB5:
664      case GL_RGB8:
665      case GL_RGB10:
666      case GL_RGB12:
667      case GL_RGB16:
668      case 4:
669      case GL_ABGR_EXT:
670      case GL_RGBA:
671      case GL_BGRA:
672      case GL_RGBA2:
673      case GL_RGBA4:
674      case GL_RGB5_A1:
675      case GL_RGBA8:
676      case GL_RGB10_A2:
677      case GL_RGBA12:
678      case GL_RGBA16:
679      /* float texture formats */
680      case GL_ALPHA16F_ARB:
681      case GL_ALPHA32F_ARB:
682      case GL_LUMINANCE16F_ARB:
683      case GL_LUMINANCE32F_ARB:
684      case GL_LUMINANCE_ALPHA16F_ARB:
685      case GL_LUMINANCE_ALPHA32F_ARB:
686      case GL_INTENSITY16F_ARB:
687      case GL_INTENSITY32F_ARB:
688      case GL_R16F:
689      case GL_R32F:
690      case GL_RG16F:
691      case GL_RG32F:
692      case GL_RGB16F_ARB:
693      case GL_RGB32F_ARB:
694      case GL_RGBA16F_ARB:
695      case GL_RGBA32F_ARB:
696      /* compressed formats */
697      case GL_COMPRESSED_ALPHA:
698      case GL_COMPRESSED_LUMINANCE:
699      case GL_COMPRESSED_LUMINANCE_ALPHA:
700      case GL_COMPRESSED_INTENSITY:
701      case GL_COMPRESSED_RED:
702      case GL_COMPRESSED_RG:
703      case GL_COMPRESSED_RGB:
704      case GL_COMPRESSED_RGBA:
705      case GL_RGB_S3TC:
706      case GL_RGB4_S3TC:
707      case GL_RGBA_S3TC:
708      case GL_RGBA4_S3TC:
709      case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
710      case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
711      case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
712      case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
713      case GL_COMPRESSED_RGB_FXT1_3DFX:
714      case GL_COMPRESSED_RGBA_FXT1_3DFX:
715#if FEATURE_EXT_texture_sRGB
716      case GL_SRGB_EXT:
717      case GL_SRGB8_EXT:
718      case GL_SRGB_ALPHA_EXT:
719      case GL_SRGB8_ALPHA8_EXT:
720      case GL_SLUMINANCE_ALPHA_EXT:
721      case GL_SLUMINANCE8_ALPHA8_EXT:
722      case GL_SLUMINANCE_EXT:
723      case GL_SLUMINANCE8_EXT:
724      case GL_COMPRESSED_SRGB_EXT:
725      case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
726      case GL_COMPRESSED_SRGB_ALPHA_EXT:
727      case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
728      case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
729      case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
730      case GL_COMPRESSED_SLUMINANCE_EXT:
731      case GL_COMPRESSED_SLUMINANCE_ALPHA_EXT:
732#endif /* FEATURE_EXT_texture_sRGB */
733      case GL_COMPRESSED_RED_RGTC1:
734      case GL_COMPRESSED_SIGNED_RED_RGTC1:
735      case GL_COMPRESSED_RG_RGTC2:
736      case GL_COMPRESSED_SIGNED_RG_RGTC2:
737      case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
738      case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
739      case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
740      case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
741      case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
742      /* generic integer formats */
743      case GL_RED_INTEGER_EXT:
744      case GL_GREEN_INTEGER_EXT:
745      case GL_BLUE_INTEGER_EXT:
746      case GL_ALPHA_INTEGER_EXT:
747      case GL_RGB_INTEGER_EXT:
748      case GL_RGBA_INTEGER_EXT:
749      case GL_BGR_INTEGER_EXT:
750      case GL_BGRA_INTEGER_EXT:
751      case GL_LUMINANCE_INTEGER_EXT:
752      case GL_LUMINANCE_ALPHA_INTEGER_EXT:
753      /* sized integer formats */
754      case GL_RGBA32UI_EXT:
755      case GL_RGB32UI_EXT:
756      case GL_ALPHA32UI_EXT:
757      case GL_INTENSITY32UI_EXT:
758      case GL_LUMINANCE32UI_EXT:
759      case GL_LUMINANCE_ALPHA32UI_EXT:
760      case GL_RGBA16UI_EXT:
761      case GL_RGB16UI_EXT:
762      case GL_ALPHA16UI_EXT:
763      case GL_INTENSITY16UI_EXT:
764      case GL_LUMINANCE16UI_EXT:
765      case GL_LUMINANCE_ALPHA16UI_EXT:
766      case GL_RGBA8UI_EXT:
767      case GL_RGB8UI_EXT:
768      case GL_ALPHA8UI_EXT:
769      case GL_INTENSITY8UI_EXT:
770      case GL_LUMINANCE8UI_EXT:
771      case GL_LUMINANCE_ALPHA8UI_EXT:
772      case GL_RGBA32I_EXT:
773      case GL_RGB32I_EXT:
774      case GL_ALPHA32I_EXT:
775      case GL_INTENSITY32I_EXT:
776      case GL_LUMINANCE32I_EXT:
777      case GL_LUMINANCE_ALPHA32I_EXT:
778      case GL_RGBA16I_EXT:
779      case GL_RGB16I_EXT:
780      case GL_ALPHA16I_EXT:
781      case GL_INTENSITY16I_EXT:
782      case GL_LUMINANCE16I_EXT:
783      case GL_LUMINANCE_ALPHA16I_EXT:
784      case GL_RGBA8I_EXT:
785      case GL_RGB8I_EXT:
786      case GL_ALPHA8I_EXT:
787      case GL_INTENSITY8I_EXT:
788      case GL_LUMINANCE8I_EXT:
789      case GL_LUMINANCE_ALPHA8I_EXT:
790      /* signed, normalized texture formats */
791      case GL_RED_SNORM:
792      case GL_R8_SNORM:
793      case GL_R16_SNORM:
794      case GL_RG_SNORM:
795      case GL_RG8_SNORM:
796      case GL_RG16_SNORM:
797      case GL_RGB_SNORM:
798      case GL_RGB8_SNORM:
799      case GL_RGB16_SNORM:
800      case GL_RGBA_SNORM:
801      case GL_RGBA8_SNORM:
802      case GL_RGBA16_SNORM:
803      case GL_ALPHA_SNORM:
804      case GL_ALPHA8_SNORM:
805      case GL_ALPHA16_SNORM:
806      case GL_LUMINANCE_SNORM:
807      case GL_LUMINANCE8_SNORM:
808      case GL_LUMINANCE16_SNORM:
809      case GL_LUMINANCE_ALPHA_SNORM:
810      case GL_LUMINANCE8_ALPHA8_SNORM:
811      case GL_LUMINANCE16_ALPHA16_SNORM:
812      case GL_INTENSITY_SNORM:
813      case GL_INTENSITY8_SNORM:
814      case GL_INTENSITY16_SNORM:
815      case GL_RGB9_E5:
816      case GL_R11F_G11F_B10F:
817         return GL_TRUE;
818      case GL_YCBCR_MESA:  /* not considered to be RGB */
819         /* fall-through */
820      default:
821         return GL_FALSE;
822   }
823}
824
825
826/**
827 * Test if the given image format is a depth component format.
828 */
829GLboolean
830_mesa_is_depth_format(GLenum format)
831{
832   switch (format) {
833      case GL_DEPTH_COMPONENT:
834      case GL_DEPTH_COMPONENT16:
835      case GL_DEPTH_COMPONENT24:
836      case GL_DEPTH_COMPONENT32:
837      case GL_DEPTH_COMPONENT32F:
838         return GL_TRUE;
839      default:
840         return GL_FALSE;
841   }
842}
843
844
845/**
846 * Test if the given image format is a stencil format.
847 */
848GLboolean
849_mesa_is_stencil_format(GLenum format)
850{
851   switch (format) {
852      case GL_STENCIL_INDEX:
853      case GL_DEPTH_STENCIL:
854         return GL_TRUE;
855      default:
856         return GL_FALSE;
857   }
858}
859
860
861/**
862 * Test if the given image format is a YCbCr format.
863 */
864GLboolean
865_mesa_is_ycbcr_format(GLenum format)
866{
867   switch (format) {
868      case GL_YCBCR_MESA:
869         return GL_TRUE;
870      default:
871         return GL_FALSE;
872   }
873}
874
875
876/**
877 * Test if the given image format is a depth+stencil format.
878 */
879GLboolean
880_mesa_is_depthstencil_format(GLenum format)
881{
882   switch (format) {
883      case GL_DEPTH24_STENCIL8_EXT:
884      case GL_DEPTH_STENCIL_EXT:
885      case GL_DEPTH32F_STENCIL8:
886         return GL_TRUE;
887      default:
888         return GL_FALSE;
889   }
890}
891
892
893/**
894 * Test if the given image format is a depth or stencil format.
895 */
896GLboolean
897_mesa_is_depth_or_stencil_format(GLenum format)
898{
899   switch (format) {
900      case GL_DEPTH_COMPONENT:
901      case GL_DEPTH_COMPONENT16:
902      case GL_DEPTH_COMPONENT24:
903      case GL_DEPTH_COMPONENT32:
904      case GL_STENCIL_INDEX:
905      case GL_STENCIL_INDEX1_EXT:
906      case GL_STENCIL_INDEX4_EXT:
907      case GL_STENCIL_INDEX8_EXT:
908      case GL_STENCIL_INDEX16_EXT:
909      case GL_DEPTH_STENCIL_EXT:
910      case GL_DEPTH24_STENCIL8_EXT:
911      case GL_DEPTH_COMPONENT32F:
912      case GL_DEPTH32F_STENCIL8:
913         return GL_TRUE;
914      default:
915         return GL_FALSE;
916   }
917}
918
919
920/**
921 * Test if the given image format is a dudv format.
922 */
923GLboolean
924_mesa_is_dudv_format(GLenum format)
925{
926   switch (format) {
927      case GL_DUDV_ATI:
928      case GL_DU8DV8_ATI:
929         return GL_TRUE;
930      default:
931         return GL_FALSE;
932   }
933}
934
935
936/**
937 * Test if the given format is an integer (non-normalized) format.
938 */
939GLboolean
940_mesa_is_integer_format(GLenum format)
941{
942   switch (format) {
943   /* generic integer formats */
944   case GL_RED_INTEGER_EXT:
945   case GL_GREEN_INTEGER_EXT:
946   case GL_BLUE_INTEGER_EXT:
947   case GL_ALPHA_INTEGER_EXT:
948   case GL_RGB_INTEGER_EXT:
949   case GL_RGBA_INTEGER_EXT:
950   case GL_BGR_INTEGER_EXT:
951   case GL_BGRA_INTEGER_EXT:
952   case GL_LUMINANCE_INTEGER_EXT:
953   case GL_LUMINANCE_ALPHA_INTEGER_EXT:
954   /* specific integer formats */
955   case GL_RGBA32UI_EXT:
956   case GL_RGB32UI_EXT:
957   case GL_RG32UI:
958   case GL_R32UI:
959   case GL_ALPHA32UI_EXT:
960   case GL_INTENSITY32UI_EXT:
961   case GL_LUMINANCE32UI_EXT:
962   case GL_LUMINANCE_ALPHA32UI_EXT:
963   case GL_RGBA16UI_EXT:
964   case GL_RGB16UI_EXT:
965   case GL_RG16UI:
966   case GL_R16UI:
967   case GL_ALPHA16UI_EXT:
968   case GL_INTENSITY16UI_EXT:
969   case GL_LUMINANCE16UI_EXT:
970   case GL_LUMINANCE_ALPHA16UI_EXT:
971   case GL_RGBA8UI_EXT:
972   case GL_RGB8UI_EXT:
973   case GL_RG8UI:
974   case GL_R8UI:
975   case GL_ALPHA8UI_EXT:
976   case GL_INTENSITY8UI_EXT:
977   case GL_LUMINANCE8UI_EXT:
978   case GL_LUMINANCE_ALPHA8UI_EXT:
979   case GL_RGBA32I_EXT:
980   case GL_RGB32I_EXT:
981   case GL_RG32I:
982   case GL_R32I:
983   case GL_ALPHA32I_EXT:
984   case GL_INTENSITY32I_EXT:
985   case GL_LUMINANCE32I_EXT:
986   case GL_LUMINANCE_ALPHA32I_EXT:
987   case GL_RGBA16I_EXT:
988   case GL_RGB16I_EXT:
989   case GL_RG16I:
990   case GL_R16I:
991   case GL_ALPHA16I_EXT:
992   case GL_INTENSITY16I_EXT:
993   case GL_LUMINANCE16I_EXT:
994   case GL_LUMINANCE_ALPHA16I_EXT:
995   case GL_RGBA8I_EXT:
996   case GL_RGB8I_EXT:
997   case GL_RG8I:
998   case GL_R8I:
999   case GL_ALPHA8I_EXT:
1000   case GL_INTENSITY8I_EXT:
1001   case GL_LUMINANCE8I_EXT:
1002   case GL_LUMINANCE_ALPHA8I_EXT:
1003      return GL_TRUE;
1004   default:
1005      return GL_FALSE;
1006   }
1007}
1008
1009
1010/**
1011 * Test if an image format is a supported compressed format.
1012 * \param format the internal format token provided by the user.
1013 * \return GL_TRUE if compressed, GL_FALSE if uncompressed
1014 */
1015GLboolean
1016_mesa_is_compressed_format(struct gl_context *ctx, GLenum format)
1017{
1018   switch (format) {
1019   case GL_COMPRESSED_RGB_S3TC_DXT1_EXT:
1020   case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT:
1021   case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT:
1022   case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT:
1023      return ctx->Extensions.EXT_texture_compression_s3tc;
1024   case GL_RGB_S3TC:
1025   case GL_RGB4_S3TC:
1026   case GL_RGBA_S3TC:
1027   case GL_RGBA4_S3TC:
1028      return ctx->Extensions.S3_s3tc;
1029   case GL_COMPRESSED_SRGB_S3TC_DXT1_EXT:
1030   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT:
1031   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT:
1032   case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
1033      return ctx->Extensions.EXT_texture_sRGB
1034         && ctx->Extensions.EXT_texture_compression_s3tc;
1035   case GL_COMPRESSED_RGB_FXT1_3DFX:
1036   case GL_COMPRESSED_RGBA_FXT1_3DFX:
1037      return ctx->Extensions.TDFX_texture_compression_FXT1;
1038   case GL_COMPRESSED_RED_RGTC1:
1039   case GL_COMPRESSED_SIGNED_RED_RGTC1:
1040   case GL_COMPRESSED_RG_RGTC2:
1041   case GL_COMPRESSED_SIGNED_RG_RGTC2:
1042      return ctx->Extensions.ARB_texture_compression_rgtc;
1043   case GL_COMPRESSED_LUMINANCE_LATC1_EXT:
1044   case GL_COMPRESSED_SIGNED_LUMINANCE_LATC1_EXT:
1045   case GL_COMPRESSED_LUMINANCE_ALPHA_LATC2_EXT:
1046   case GL_COMPRESSED_SIGNED_LUMINANCE_ALPHA_LATC2_EXT:
1047      return ctx->Extensions.EXT_texture_compression_latc;
1048   case GL_COMPRESSED_LUMINANCE_ALPHA_3DC_ATI:
1049      return ctx->Extensions.ATI_texture_compression_3dc;
1050#if FEATURE_ES
1051   case GL_PALETTE4_RGB8_OES:
1052   case GL_PALETTE4_RGBA8_OES:
1053   case GL_PALETTE4_R5_G6_B5_OES:
1054   case GL_PALETTE4_RGBA4_OES:
1055   case GL_PALETTE4_RGB5_A1_OES:
1056   case GL_PALETTE8_RGB8_OES:
1057   case GL_PALETTE8_RGBA8_OES:
1058   case GL_PALETTE8_R5_G6_B5_OES:
1059   case GL_PALETTE8_RGBA4_OES:
1060   case GL_PALETTE8_RGB5_A1_OES:
1061      return ctx->API == API_OPENGLES;
1062#endif
1063   default:
1064      return GL_FALSE;
1065   }
1066}
1067
1068
1069/**
1070 * Return the address of a specific pixel in an image (1D, 2D or 3D).
1071 *
1072 * Pixel unpacking/packing parameters are observed according to \p packing.
1073 *
1074 * \param dimensions either 1, 2 or 3 to indicate dimensionality of image
1075 * \param image  starting address of image data
1076 * \param width  the image width
1077 * \param height  theimage height
1078 * \param format  the pixel format
1079 * \param type  the pixel data type
1080 * \param packing  the pixelstore attributes
1081 * \param img  which image in the volume (0 for 1D or 2D images)
1082 * \param row  row of pixel in the image (0 for 1D images)
1083 * \param column column of pixel in the image
1084 *
1085 * \return address of pixel on success, or NULL on error.
1086 *
1087 * \sa gl_pixelstore_attrib.
1088 */
1089GLvoid *
1090_mesa_image_address( GLuint dimensions,
1091                     const struct gl_pixelstore_attrib *packing,
1092                     const GLvoid *image,
1093                     GLsizei width, GLsizei height,
1094                     GLenum format, GLenum type,
1095                     GLint img, GLint row, GLint column )
1096{
1097   GLint alignment;        /* 1, 2 or 4 */
1098   GLint pixels_per_row;
1099   GLint rows_per_image;
1100   GLint skiprows;
1101   GLint skippixels;
1102   GLint skipimages;       /* for 3-D volume images */
1103   GLubyte *pixel_addr;
1104
1105   ASSERT(dimensions >= 1 && dimensions <= 3);
1106
1107   alignment = packing->Alignment;
1108   if (packing->RowLength > 0) {
1109      pixels_per_row = packing->RowLength;
1110   }
1111   else {
1112      pixels_per_row = width;
1113   }
1114   if (packing->ImageHeight > 0) {
1115      rows_per_image = packing->ImageHeight;
1116   }
1117   else {
1118      rows_per_image = height;
1119   }
1120
1121   skippixels = packing->SkipPixels;
1122   /* Note: SKIP_ROWS _is_ used for 1D images */
1123   skiprows = packing->SkipRows;
1124   /* Note: SKIP_IMAGES is only used for 3D images */
1125   skipimages = (dimensions == 3) ? packing->SkipImages : 0;
1126
1127   if (type == GL_BITMAP) {
1128      /* BITMAP data */
1129      GLint comp_per_pixel;   /* components per pixel */
1130      GLint bytes_per_comp;   /* bytes per component */
1131      GLint bytes_per_row;
1132      GLint bytes_per_image;
1133
1134      /* Compute bytes per component */
1135      bytes_per_comp = _mesa_sizeof_packed_type( type );
1136      if (bytes_per_comp < 0) {
1137         return NULL;
1138      }
1139
1140      /* Compute number of components per pixel */
1141      comp_per_pixel = _mesa_components_in_format( format );
1142      if (comp_per_pixel < 0) {
1143         return NULL;
1144      }
1145
1146      bytes_per_row = alignment
1147                    * CEILING( comp_per_pixel*pixels_per_row, 8*alignment );
1148
1149      bytes_per_image = bytes_per_row * rows_per_image;
1150
1151      pixel_addr = (GLubyte *) image
1152                 + (skipimages + img) * bytes_per_image
1153                 + (skiprows + row) * bytes_per_row
1154                 + (skippixels + column) / 8;
1155   }
1156   else {
1157      /* Non-BITMAP data */
1158      GLint bytes_per_pixel, bytes_per_row, remainder, bytes_per_image;
1159      GLint topOfImage;
1160
1161      bytes_per_pixel = _mesa_bytes_per_pixel( format, type );
1162
1163      /* The pixel type and format should have been error checked earlier */
1164      assert(bytes_per_pixel > 0);
1165
1166      bytes_per_row = pixels_per_row * bytes_per_pixel;
1167      remainder = bytes_per_row % alignment;
1168      if (remainder > 0)
1169         bytes_per_row += (alignment - remainder);
1170
1171      ASSERT(bytes_per_row % alignment == 0);
1172
1173      bytes_per_image = bytes_per_row * rows_per_image;
1174
1175      if (packing->Invert) {
1176         /* set pixel_addr to the last row */
1177         topOfImage = bytes_per_row * (height - 1);
1178         bytes_per_row = -bytes_per_row;
1179      }
1180      else {
1181         topOfImage = 0;
1182      }
1183
1184      /* compute final pixel address */
1185      pixel_addr = (GLubyte *) image
1186                 + (skipimages + img) * bytes_per_image
1187                 + topOfImage
1188                 + (skiprows + row) * bytes_per_row
1189                 + (skippixels + column) * bytes_per_pixel;
1190   }
1191
1192   return (GLvoid *) pixel_addr;
1193}
1194
1195
1196GLvoid *
1197_mesa_image_address1d( const struct gl_pixelstore_attrib *packing,
1198                       const GLvoid *image,
1199                       GLsizei width,
1200                       GLenum format, GLenum type,
1201                       GLint column )
1202{
1203   return _mesa_image_address(1, packing, image, width, 1,
1204                              format, type, 0, 0, column);
1205}
1206
1207
1208GLvoid *
1209_mesa_image_address2d( const struct gl_pixelstore_attrib *packing,
1210                       const GLvoid *image,
1211                       GLsizei width, GLsizei height,
1212                       GLenum format, GLenum type,
1213                       GLint row, GLint column )
1214{
1215   return _mesa_image_address(2, packing, image, width, height,
1216                              format, type, 0, row, column);
1217}
1218
1219
1220GLvoid *
1221_mesa_image_address3d( const struct gl_pixelstore_attrib *packing,
1222                       const GLvoid *image,
1223                       GLsizei width, GLsizei height,
1224                       GLenum format, GLenum type,
1225                       GLint img, GLint row, GLint column )
1226{
1227   return _mesa_image_address(3, packing, image, width, height,
1228                              format, type, img, row, column);
1229}
1230
1231
1232
1233/**
1234 * Compute the stride (in bytes) between image rows.
1235 *
1236 * \param packing the pixelstore attributes
1237 * \param width image width.
1238 * \param format pixel format.
1239 * \param type pixel data type.
1240 *
1241 * \return the stride in bytes for the given parameters, or -1 if error
1242 */
1243GLint
1244_mesa_image_row_stride( const struct gl_pixelstore_attrib *packing,
1245                        GLint width, GLenum format, GLenum type )
1246{
1247   GLint bytesPerRow, remainder;
1248
1249   ASSERT(packing);
1250
1251   if (type == GL_BITMAP) {
1252      if (packing->RowLength == 0) {
1253         bytesPerRow = (width + 7) / 8;
1254      }
1255      else {
1256         bytesPerRow = (packing->RowLength + 7) / 8;
1257      }
1258   }
1259   else {
1260      /* Non-BITMAP data */
1261      const GLint bytesPerPixel = _mesa_bytes_per_pixel(format, type);
1262      if (bytesPerPixel <= 0)
1263         return -1;  /* error */
1264      if (packing->RowLength == 0) {
1265         bytesPerRow = bytesPerPixel * width;
1266      }
1267      else {
1268         bytesPerRow = bytesPerPixel * packing->RowLength;
1269      }
1270   }
1271
1272   remainder = bytesPerRow % packing->Alignment;
1273   if (remainder > 0) {
1274      bytesPerRow += (packing->Alignment - remainder);
1275   }
1276
1277   if (packing->Invert) {
1278      /* negate the bytes per row (negative row stride) */
1279      bytesPerRow = -bytesPerRow;
1280   }
1281
1282   return bytesPerRow;
1283}
1284
1285
1286/*
1287 * Compute the stride between images in a 3D texture (in bytes) for the given
1288 * pixel packing parameters and image width, format and type.
1289 */
1290GLint
1291_mesa_image_image_stride( const struct gl_pixelstore_attrib *packing,
1292                          GLint width, GLint height,
1293                          GLenum format, GLenum type )
1294{
1295   GLint bytesPerRow, bytesPerImage, remainder;
1296
1297   ASSERT(packing);
1298
1299   if (type == GL_BITMAP) {
1300      if (packing->RowLength == 0) {
1301         bytesPerRow = (width + 7) / 8;
1302      }
1303      else {
1304         bytesPerRow = (packing->RowLength + 7) / 8;
1305      }
1306   }
1307   else {
1308      const GLint bytesPerPixel = _mesa_bytes_per_pixel(format, type);
1309
1310      if (bytesPerPixel <= 0)
1311         return -1;  /* error */
1312      if (packing->RowLength == 0) {
1313         bytesPerRow = bytesPerPixel * width;
1314      }
1315      else {
1316         bytesPerRow = bytesPerPixel * packing->RowLength;
1317      }
1318   }
1319
1320   remainder = bytesPerRow % packing->Alignment;
1321   if (remainder > 0)
1322      bytesPerRow += (packing->Alignment - remainder);
1323
1324   if (packing->ImageHeight == 0)
1325      bytesPerImage = bytesPerRow * height;
1326   else
1327      bytesPerImage = bytesPerRow * packing->ImageHeight;
1328
1329   return bytesPerImage;
1330}
1331
1332
1333
1334/**
1335 * "Expand" a bitmap from 1-bit per pixel to 8-bits per pixel.
1336 * This is typically used to convert a bitmap into a GLubyte/pixel texture.
1337 * "On" bits will set texels to \p onValue.
1338 * "Off" bits will not modify texels.
1339 * \param width  src bitmap width in pixels
1340 * \param height  src bitmap height in pixels
1341 * \param unpack  bitmap unpacking state
1342 * \param bitmap  the src bitmap data
1343 * \param destBuffer  start of dest buffer
1344 * \param destStride  row stride in dest buffer
1345 * \param onValue  if bit is 1, set destBuffer pixel to this value
1346 */
1347void
1348_mesa_expand_bitmap(GLsizei width, GLsizei height,
1349                    const struct gl_pixelstore_attrib *unpack,
1350                    const GLubyte *bitmap,
1351                    GLubyte *destBuffer, GLint destStride,
1352                    GLubyte onValue)
1353{
1354   const GLubyte *srcRow = (const GLubyte *)
1355      _mesa_image_address2d(unpack, bitmap, width, height,
1356                            GL_COLOR_INDEX, GL_BITMAP, 0, 0);
1357   const GLint srcStride = _mesa_image_row_stride(unpack, width,
1358                                                  GL_COLOR_INDEX, GL_BITMAP);
1359   GLint row, col;
1360
1361#define SET_PIXEL(COL, ROW) \
1362   destBuffer[(ROW) * destStride + (COL)] = onValue;
1363
1364   for (row = 0; row < height; row++) {
1365      const GLubyte *src = srcRow;
1366
1367      if (unpack->LsbFirst) {
1368         /* Lsb first */
1369         GLubyte mask = 1U << (unpack->SkipPixels & 0x7);
1370         for (col = 0; col < width; col++) {
1371
1372            if (*src & mask) {
1373               SET_PIXEL(col, row);
1374            }
1375
1376            if (mask == 128U) {
1377               src++;
1378               mask = 1U;
1379            }
1380            else {
1381               mask = mask << 1;
1382            }
1383         }
1384
1385         /* get ready for next row */
1386         if (mask != 1)
1387            src++;
1388      }
1389      else {
1390         /* Msb first */
1391         GLubyte mask = 128U >> (unpack->SkipPixels & 0x7);
1392         for (col = 0; col < width; col++) {
1393
1394            if (*src & mask) {
1395               SET_PIXEL(col, row);
1396            }
1397
1398            if (mask == 1U) {
1399               src++;
1400               mask = 128U;
1401            }
1402            else {
1403               mask = mask >> 1;
1404            }
1405         }
1406
1407         /* get ready for next row */
1408         if (mask != 128)
1409            src++;
1410      }
1411
1412      srcRow += srcStride;
1413   } /* row */
1414
1415#undef SET_PIXEL
1416}
1417
1418
1419
1420
1421/**
1422 * Convert an array of RGBA colors from one datatype to another.
1423 * NOTE: src may equal dst.  In that case, we use a temporary buffer.
1424 */
1425void
1426_mesa_convert_colors(GLenum srcType, const GLvoid *src,
1427                     GLenum dstType, GLvoid *dst,
1428                     GLuint count, const GLubyte mask[])
1429{
1430   GLuint tempBuffer[MAX_WIDTH][4];
1431   const GLboolean useTemp = (src == dst);
1432
1433   ASSERT(srcType != dstType);
1434
1435   switch (srcType) {
1436   case GL_UNSIGNED_BYTE:
1437      if (dstType == GL_UNSIGNED_SHORT) {
1438         const GLubyte (*src1)[4] = (const GLubyte (*)[4]) src;
1439         GLushort (*dst2)[4] = (GLushort (*)[4]) (useTemp ? tempBuffer : dst);
1440         GLuint i;
1441         for (i = 0; i < count; i++) {
1442            if (!mask || mask[i]) {
1443               dst2[i][RCOMP] = UBYTE_TO_USHORT(src1[i][RCOMP]);
1444               dst2[i][GCOMP] = UBYTE_TO_USHORT(src1[i][GCOMP]);
1445               dst2[i][BCOMP] = UBYTE_TO_USHORT(src1[i][BCOMP]);
1446               dst2[i][ACOMP] = UBYTE_TO_USHORT(src1[i][ACOMP]);
1447            }
1448         }
1449         if (useTemp)
1450            memcpy(dst, tempBuffer, count * 4 * sizeof(GLushort));
1451      }
1452      else {
1453         const GLubyte (*src1)[4] = (const GLubyte (*)[4]) src;
1454         GLfloat (*dst4)[4] = (GLfloat (*)[4]) (useTemp ? tempBuffer : dst);
1455         GLuint i;
1456         ASSERT(dstType == GL_FLOAT);
1457         for (i = 0; i < count; i++) {
1458            if (!mask || mask[i]) {
1459               dst4[i][RCOMP] = UBYTE_TO_FLOAT(src1[i][RCOMP]);
1460               dst4[i][GCOMP] = UBYTE_TO_FLOAT(src1[i][GCOMP]);
1461               dst4[i][BCOMP] = UBYTE_TO_FLOAT(src1[i][BCOMP]);
1462               dst4[i][ACOMP] = UBYTE_TO_FLOAT(src1[i][ACOMP]);
1463            }
1464         }
1465         if (useTemp)
1466            memcpy(dst, tempBuffer, count * 4 * sizeof(GLfloat));
1467      }
1468      break;
1469   case GL_UNSIGNED_SHORT:
1470      if (dstType == GL_UNSIGNED_BYTE) {
1471         const GLushort (*src2)[4] = (const GLushort (*)[4]) src;
1472         GLubyte (*dst1)[4] = (GLubyte (*)[4]) (useTemp ? tempBuffer : dst);
1473         GLuint i;
1474         for (i = 0; i < count; i++) {
1475            if (!mask || mask[i]) {
1476               dst1[i][RCOMP] = USHORT_TO_UBYTE(src2[i][RCOMP]);
1477               dst1[i][GCOMP] = USHORT_TO_UBYTE(src2[i][GCOMP]);
1478               dst1[i][BCOMP] = USHORT_TO_UBYTE(src2[i][BCOMP]);
1479               dst1[i][ACOMP] = USHORT_TO_UBYTE(src2[i][ACOMP]);
1480            }
1481         }
1482         if (useTemp)
1483            memcpy(dst, tempBuffer, count * 4 * sizeof(GLubyte));
1484      }
1485      else {
1486         const GLushort (*src2)[4] = (const GLushort (*)[4]) src;
1487         GLfloat (*dst4)[4] = (GLfloat (*)[4]) (useTemp ? tempBuffer : dst);
1488         GLuint i;
1489         ASSERT(dstType == GL_FLOAT);
1490         for (i = 0; i < count; i++) {
1491            if (!mask || mask[i]) {
1492               dst4[i][RCOMP] = USHORT_TO_FLOAT(src2[i][RCOMP]);
1493               dst4[i][GCOMP] = USHORT_TO_FLOAT(src2[i][GCOMP]);
1494               dst4[i][BCOMP] = USHORT_TO_FLOAT(src2[i][BCOMP]);
1495               dst4[i][ACOMP] = USHORT_TO_FLOAT(src2[i][ACOMP]);
1496            }
1497         }
1498         if (useTemp)
1499            memcpy(dst, tempBuffer, count * 4 * sizeof(GLfloat));
1500      }
1501      break;
1502   case GL_FLOAT:
1503      if (dstType == GL_UNSIGNED_BYTE) {
1504         const GLfloat (*src4)[4] = (const GLfloat (*)[4]) src;
1505         GLubyte (*dst1)[4] = (GLubyte (*)[4]) (useTemp ? tempBuffer : dst);
1506         GLuint i;
1507         for (i = 0; i < count; i++) {
1508            if (!mask || mask[i])
1509               _mesa_unclamped_float_rgba_to_ubyte(dst1[i], src4[i]);
1510         }
1511         if (useTemp)
1512            memcpy(dst, tempBuffer, count * 4 * sizeof(GLubyte));
1513      }
1514      else {
1515         const GLfloat (*src4)[4] = (const GLfloat (*)[4]) src;
1516         GLushort (*dst2)[4] = (GLushort (*)[4]) (useTemp ? tempBuffer : dst);
1517         GLuint i;
1518         ASSERT(dstType == GL_UNSIGNED_SHORT);
1519         for (i = 0; i < count; i++) {
1520            if (!mask || mask[i]) {
1521               UNCLAMPED_FLOAT_TO_USHORT(dst2[i][RCOMP], src4[i][RCOMP]);
1522               UNCLAMPED_FLOAT_TO_USHORT(dst2[i][GCOMP], src4[i][GCOMP]);
1523               UNCLAMPED_FLOAT_TO_USHORT(dst2[i][BCOMP], src4[i][BCOMP]);
1524               UNCLAMPED_FLOAT_TO_USHORT(dst2[i][ACOMP], src4[i][ACOMP]);
1525            }
1526         }
1527         if (useTemp)
1528            memcpy(dst, tempBuffer, count * 4 * sizeof(GLushort));
1529      }
1530      break;
1531   default:
1532      _mesa_problem(NULL, "Invalid datatype in _mesa_convert_colors");
1533   }
1534}
1535
1536
1537
1538
1539/**
1540 * Perform basic clipping for glDrawPixels.  The image's position and size
1541 * and the unpack SkipPixels and SkipRows are adjusted so that the image
1542 * region is entirely within the window and scissor bounds.
1543 * NOTE: this will only work when glPixelZoom is (1, 1) or (1, -1).
1544 * If Pixel.ZoomY is -1, *destY will be changed to be the first row which
1545 * we'll actually write.  Beforehand, *destY-1 is the first drawing row.
1546 *
1547 * \return  GL_TRUE if image is ready for drawing or
1548 *          GL_FALSE if image was completely clipped away (draw nothing)
1549 */
1550GLboolean
1551_mesa_clip_drawpixels(const struct gl_context *ctx,
1552                      GLint *destX, GLint *destY,
1553                      GLsizei *width, GLsizei *height,
1554                      struct gl_pixelstore_attrib *unpack)
1555{
1556   const struct gl_framebuffer *buffer = ctx->DrawBuffer;
1557
1558   if (unpack->RowLength == 0) {
1559      unpack->RowLength = *width;
1560   }
1561
1562   ASSERT(ctx->Pixel.ZoomX == 1.0F);
1563   ASSERT(ctx->Pixel.ZoomY == 1.0F || ctx->Pixel.ZoomY == -1.0F);
1564
1565   /* left clipping */
1566   if (*destX < buffer->_Xmin) {
1567      unpack->SkipPixels += (buffer->_Xmin - *destX);
1568      *width -= (buffer->_Xmin - *destX);
1569      *destX = buffer->_Xmin;
1570   }
1571   /* right clipping */
1572   if (*destX + *width > buffer->_Xmax)
1573      *width -= (*destX + *width - buffer->_Xmax);
1574
1575   if (*width <= 0)
1576      return GL_FALSE;
1577
1578   if (ctx->Pixel.ZoomY == 1.0F) {
1579      /* bottom clipping */
1580      if (*destY < buffer->_Ymin) {
1581         unpack->SkipRows += (buffer->_Ymin - *destY);
1582         *height -= (buffer->_Ymin - *destY);
1583         *destY = buffer->_Ymin;
1584      }
1585      /* top clipping */
1586      if (*destY + *height > buffer->_Ymax)
1587         *height -= (*destY + *height - buffer->_Ymax);
1588   }
1589   else { /* upside down */
1590      /* top clipping */
1591      if (*destY > buffer->_Ymax) {
1592         unpack->SkipRows += (*destY - buffer->_Ymax);
1593         *height -= (*destY - buffer->_Ymax);
1594         *destY = buffer->_Ymax;
1595      }
1596      /* bottom clipping */
1597      if (*destY - *height < buffer->_Ymin)
1598         *height -= (buffer->_Ymin - (*destY - *height));
1599      /* adjust destY so it's the first row to write to */
1600      (*destY)--;
1601   }
1602
1603   if (*height <= 0)
1604      return GL_FALSE;
1605
1606   return GL_TRUE;
1607}
1608
1609
1610/**
1611 * Perform clipping for glReadPixels.  The image's window position
1612 * and size, and the pack skipPixels, skipRows and rowLength are adjusted
1613 * so that the image region is entirely within the window bounds.
1614 * Note: this is different from _mesa_clip_drawpixels() in that the
1615 * scissor box is ignored, and we use the bounds of the current readbuffer
1616 * surface.
1617 *
1618 * \return  GL_TRUE if region to read is in bounds
1619 *          GL_FALSE if region is completely out of bounds (nothing to read)
1620 */
1621GLboolean
1622_mesa_clip_readpixels(const struct gl_context *ctx,
1623                      GLint *srcX, GLint *srcY,
1624                      GLsizei *width, GLsizei *height,
1625                      struct gl_pixelstore_attrib *pack)
1626{
1627   const struct gl_framebuffer *buffer = ctx->ReadBuffer;
1628
1629   if (pack->RowLength == 0) {
1630      pack->RowLength = *width;
1631   }
1632
1633   /* left clipping */
1634   if (*srcX < 0) {
1635      pack->SkipPixels += (0 - *srcX);
1636      *width -= (0 - *srcX);
1637      *srcX = 0;
1638   }
1639   /* right clipping */
1640   if (*srcX + *width > (GLsizei) buffer->Width)
1641      *width -= (*srcX + *width - buffer->Width);
1642
1643   if (*width <= 0)
1644      return GL_FALSE;
1645
1646   /* bottom clipping */
1647   if (*srcY < 0) {
1648      pack->SkipRows += (0 - *srcY);
1649      *height -= (0 - *srcY);
1650      *srcY = 0;
1651   }
1652   /* top clipping */
1653   if (*srcY + *height > (GLsizei) buffer->Height)
1654      *height -= (*srcY + *height - buffer->Height);
1655
1656   if (*height <= 0)
1657      return GL_FALSE;
1658
1659   return GL_TRUE;
1660}
1661
1662
1663/**
1664 * Do clipping for a glCopyTexSubImage call.
1665 * The framebuffer source region might extend outside the framebuffer
1666 * bounds.  Clip the source region against the framebuffer bounds and
1667 * adjust the texture/dest position and size accordingly.
1668 *
1669 * \return GL_FALSE if region is totally clipped, GL_TRUE otherwise.
1670 */
1671GLboolean
1672_mesa_clip_copytexsubimage(const struct gl_context *ctx,
1673                           GLint *destX, GLint *destY,
1674                           GLint *srcX, GLint *srcY,
1675                           GLsizei *width, GLsizei *height)
1676{
1677   const struct gl_framebuffer *fb = ctx->ReadBuffer;
1678   const GLint srcX0 = *srcX, srcY0 = *srcY;
1679
1680   if (_mesa_clip_to_region(0, 0, fb->Width, fb->Height,
1681                            srcX, srcY, width, height)) {
1682      *destX = *destX + *srcX - srcX0;
1683      *destY = *destY + *srcY - srcY0;
1684
1685      return GL_TRUE;
1686   }
1687   else {
1688      return GL_FALSE;
1689   }
1690}
1691
1692
1693
1694/**
1695 * Clip the rectangle defined by (x, y, width, height) against the bounds
1696 * specified by [xmin, xmax) and [ymin, ymax).
1697 * \return GL_FALSE if rect is totally clipped, GL_TRUE otherwise.
1698 */
1699GLboolean
1700_mesa_clip_to_region(GLint xmin, GLint ymin,
1701                     GLint xmax, GLint ymax,
1702                     GLint *x, GLint *y,
1703                     GLsizei *width, GLsizei *height )
1704{
1705   /* left clipping */
1706   if (*x < xmin) {
1707      *width -= (xmin - *x);
1708      *x = xmin;
1709   }
1710
1711   /* right clipping */
1712   if (*x + *width > xmax)
1713      *width -= (*x + *width - xmax);
1714
1715   if (*width <= 0)
1716      return GL_FALSE;
1717
1718   /* bottom (or top) clipping */
1719   if (*y < ymin) {
1720      *height -= (ymin - *y);
1721      *y = ymin;
1722   }
1723
1724   /* top (or bottom) clipping */
1725   if (*y + *height > ymax)
1726      *height -= (*y + *height - ymax);
1727
1728   if (*height <= 0)
1729      return GL_FALSE;
1730
1731   return GL_TRUE;
1732}
1733
1734
1735/**
1736 * Clip dst coords against Xmax (or Ymax).
1737 */
1738static inline void
1739clip_right_or_top(GLint *srcX0, GLint *srcX1,
1740                  GLint *dstX0, GLint *dstX1,
1741                  GLint maxValue)
1742{
1743   GLfloat t, bias;
1744
1745   if (*dstX1 > maxValue) {
1746      /* X1 outside right edge */
1747      ASSERT(*dstX0 < maxValue); /* X0 should be inside right edge */
1748      t = (GLfloat) (maxValue - *dstX0) / (GLfloat) (*dstX1 - *dstX0);
1749      /* chop off [t, 1] part */
1750      ASSERT(t >= 0.0 && t <= 1.0);
1751      *dstX1 = maxValue;
1752      bias = (*srcX0 < *srcX1) ? 0.5F : -0.5F;
1753      *srcX1 = *srcX0 + (GLint) (t * (*srcX1 - *srcX0) + bias);
1754   }
1755   else if (*dstX0 > maxValue) {
1756      /* X0 outside right edge */
1757      ASSERT(*dstX1 < maxValue); /* X1 should be inside right edge */
1758      t = (GLfloat) (maxValue - *dstX1) / (GLfloat) (*dstX0 - *dstX1);
1759      /* chop off [t, 1] part */
1760      ASSERT(t >= 0.0 && t <= 1.0);
1761      *dstX0 = maxValue;
1762      bias = (*srcX0 < *srcX1) ? -0.5F : 0.5F;
1763      *srcX0 = *srcX1 + (GLint) (t * (*srcX0 - *srcX1) + bias);
1764   }
1765}
1766
1767
1768/**
1769 * Clip dst coords against Xmin (or Ymin).
1770 */
1771static inline void
1772clip_left_or_bottom(GLint *srcX0, GLint *srcX1,
1773                    GLint *dstX0, GLint *dstX1,
1774                    GLint minValue)
1775{
1776   GLfloat t, bias;
1777
1778   if (*dstX0 < minValue) {
1779      /* X0 outside left edge */
1780      ASSERT(*dstX1 > minValue); /* X1 should be inside left edge */
1781      t = (GLfloat) (minValue - *dstX0) / (GLfloat) (*dstX1 - *dstX0);
1782      /* chop off [0, t] part */
1783      ASSERT(t >= 0.0 && t <= 1.0);
1784      *dstX0 = minValue;
1785      bias = (*srcX0 < *srcX1) ? 0.5F : -0.5F; /* flipped??? */
1786      *srcX0 = *srcX0 + (GLint) (t * (*srcX1 - *srcX0) + bias);
1787   }
1788   else if (*dstX1 < minValue) {
1789      /* X1 outside left edge */
1790      ASSERT(*dstX0 > minValue); /* X0 should be inside left edge */
1791      t = (GLfloat) (minValue - *dstX1) / (GLfloat) (*dstX0 - *dstX1);
1792      /* chop off [0, t] part */
1793      ASSERT(t >= 0.0 && t <= 1.0);
1794      *dstX1 = minValue;
1795      bias = (*srcX0 < *srcX1) ? 0.5F : -0.5F;
1796      *srcX1 = *srcX1 + (GLint) (t * (*srcX0 - *srcX1) + bias);
1797   }
1798}
1799
1800
1801/**
1802 * Do clipping of blit src/dest rectangles.
1803 * The dest rect is clipped against both the buffer bounds and scissor bounds.
1804 * The src rect is just clipped against the buffer bounds.
1805 *
1806 * When either the src or dest rect is clipped, the other is also clipped
1807 * proportionately!
1808 *
1809 * Note that X0 need not be less than X1 (same for Y) for either the source
1810 * and dest rects.  That makes the clipping a little trickier.
1811 *
1812 * \return GL_TRUE if anything is left to draw, GL_FALSE if totally clipped
1813 */
1814GLboolean
1815_mesa_clip_blit(struct gl_context *ctx,
1816                GLint *srcX0, GLint *srcY0, GLint *srcX1, GLint *srcY1,
1817                GLint *dstX0, GLint *dstY0, GLint *dstX1, GLint *dstY1)
1818{
1819   const GLint srcXmin = 0;
1820   const GLint srcXmax = ctx->ReadBuffer->Width;
1821   const GLint srcYmin = 0;
1822   const GLint srcYmax = ctx->ReadBuffer->Height;
1823
1824   /* these include scissor bounds */
1825   const GLint dstXmin = ctx->DrawBuffer->_Xmin;
1826   const GLint dstXmax = ctx->DrawBuffer->_Xmax;
1827   const GLint dstYmin = ctx->DrawBuffer->_Ymin;
1828   const GLint dstYmax = ctx->DrawBuffer->_Ymax;
1829
1830   /*
1831   printf("PreClipX:  src: %d .. %d  dst: %d .. %d\n",
1832          *srcX0, *srcX1, *dstX0, *dstX1);
1833   printf("PreClipY:  src: %d .. %d  dst: %d .. %d\n",
1834          *srcY0, *srcY1, *dstY0, *dstY1);
1835   */
1836
1837   /* trivial rejection tests */
1838   if (*dstX0 == *dstX1)
1839      return GL_FALSE; /* no width */
1840   if (*dstX0 <= dstXmin && *dstX1 <= dstXmin)
1841      return GL_FALSE; /* totally out (left) of bounds */
1842   if (*dstX0 >= dstXmax && *dstX1 >= dstXmax)
1843      return GL_FALSE; /* totally out (right) of bounds */
1844
1845   if (*dstY0 == *dstY1)
1846      return GL_FALSE;
1847   if (*dstY0 <= dstYmin && *dstY1 <= dstYmin)
1848      return GL_FALSE;
1849   if (*dstY0 >= dstYmax && *dstY1 >= dstYmax)
1850      return GL_FALSE;
1851
1852   if (*srcX0 == *srcX1)
1853      return GL_FALSE;
1854   if (*srcX0 <= srcXmin && *srcX1 <= srcXmin)
1855      return GL_FALSE;
1856   if (*srcX0 >= srcXmax && *srcX1 >= srcXmax)
1857      return GL_FALSE;
1858
1859   if (*srcY0 == *srcY1)
1860      return GL_FALSE;
1861   if (*srcY0 <= srcYmin && *srcY1 <= srcYmin)
1862      return GL_FALSE;
1863   if (*srcY0 >= srcYmax && *srcY1 >= srcYmax)
1864      return GL_FALSE;
1865
1866   /*
1867    * dest clip
1868    */
1869   clip_right_or_top(srcX0, srcX1, dstX0, dstX1, dstXmax);
1870   clip_right_or_top(srcY0, srcY1, dstY0, dstY1, dstYmax);
1871   clip_left_or_bottom(srcX0, srcX1, dstX0, dstX1, dstXmin);
1872   clip_left_or_bottom(srcY0, srcY1, dstY0, dstY1, dstYmin);
1873
1874   /*
1875    * src clip (just swap src/dst values from above)
1876    */
1877   clip_right_or_top(dstX0, dstX1, srcX0, srcX1, srcXmax);
1878   clip_right_or_top(dstY0, dstY1, srcY0, srcY1, srcYmax);
1879   clip_left_or_bottom(dstX0, dstX1, srcX0, srcX1, srcXmin);
1880   clip_left_or_bottom(dstY0, dstY1, srcY0, srcY1, srcYmin);
1881
1882   /*
1883   printf("PostClipX: src: %d .. %d  dst: %d .. %d\n",
1884          *srcX0, *srcX1, *dstX0, *dstX1);
1885   printf("PostClipY: src: %d .. %d  dst: %d .. %d\n",
1886          *srcY0, *srcY1, *dstY0, *dstY1);
1887   */
1888
1889   ASSERT(*dstX0 >= dstXmin);
1890   ASSERT(*dstX0 <= dstXmax);
1891   ASSERT(*dstX1 >= dstXmin);
1892   ASSERT(*dstX1 <= dstXmax);
1893
1894   ASSERT(*dstY0 >= dstYmin);
1895   ASSERT(*dstY0 <= dstYmax);
1896   ASSERT(*dstY1 >= dstYmin);
1897   ASSERT(*dstY1 <= dstYmax);
1898
1899   ASSERT(*srcX0 >= srcXmin);
1900   ASSERT(*srcX0 <= srcXmax);
1901   ASSERT(*srcX1 >= srcXmin);
1902   ASSERT(*srcX1 <= srcXmax);
1903
1904   ASSERT(*srcY0 >= srcYmin);
1905   ASSERT(*srcY0 <= srcYmax);
1906   ASSERT(*srcY1 >= srcYmin);
1907   ASSERT(*srcY1 <= srcYmax);
1908
1909   return GL_TRUE;
1910}
1911