summaryrefslogtreecommitdiff
path: root/src/mesa/drivers/dri/intel/intel_fbo.c
blob: 4a83886fc16206f899b02cee30ff97aa189d8b4a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
/**************************************************************************
 * 
 * Copyright 2006 Tungsten Graphics, Inc., Cedar Park, Texas.
 * All Rights Reserved.
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * 
 **************************************************************************/


#include "main/imports.h"
#include "main/macros.h"
#include "main/mtypes.h"
#include "main/fbobject.h"
#include "main/framebuffer.h"
#include "main/renderbuffer.h"
#include "main/context.h"
#include "main/texrender.h"
#include "drivers/common/meta.h"

#include "intel_context.h"
#include "intel_batchbuffer.h"
#include "intel_buffers.h"
#include "intel_fbo.h"
#include "intel_mipmap_tree.h"
#include "intel_regions.h"

#define FILE_DEBUG_FLAG DEBUG_FBO


/**
 * Create a new framebuffer object.
 */
static struct gl_framebuffer *
intel_new_framebuffer(GLcontext * ctx, GLuint name)
{
   /* Only drawable state in intel_framebuffer at this time, just use Mesa's
    * class
    */
   return _mesa_new_framebuffer(ctx, name);
}


/** Called by gl_renderbuffer::Delete() */
static void
intel_delete_renderbuffer(struct gl_renderbuffer *rb)
{
   GET_CURRENT_CONTEXT(ctx);
   struct intel_context *intel = intel_context(ctx);
   struct intel_renderbuffer *irb = intel_renderbuffer(rb);

   ASSERT(irb);

   if (intel && irb->region) {
      intel_region_release(&irb->region);
   }

   free(irb);
}


/**
 * Return a pointer to a specific pixel in a renderbuffer.
 */
static void *
intel_get_pointer(GLcontext * ctx, struct gl_renderbuffer *rb,
                  GLint x, GLint y)
{
   /* By returning NULL we force all software rendering to go through
    * the span routines.
    */
   return NULL;
}


/**
 * Called via glRenderbufferStorageEXT() to set the format and allocate
 * storage for a user-created renderbuffer.
 */
static GLboolean
intel_alloc_renderbuffer_storage(GLcontext * ctx, struct gl_renderbuffer *rb,
                                 GLenum internalFormat,
                                 GLuint width, GLuint height)
{
   struct intel_context *intel = intel_context(ctx);
   struct intel_renderbuffer *irb = intel_renderbuffer(rb);
   int cpp;

   ASSERT(rb->Name != 0);

   switch (internalFormat) {
   case GL_R3_G3_B2:
   case GL_RGB4:
   case GL_RGB5:
      rb->Format = MESA_FORMAT_RGB565;
      rb->DataType = GL_UNSIGNED_BYTE;
      break;
   case GL_RGB:
   case GL_RGB8:
   case GL_RGB10:
   case GL_RGB12:
   case GL_RGB16:
      rb->Format = MESA_FORMAT_XRGB8888;
      rb->DataType = GL_UNSIGNED_BYTE;
      break;
   case GL_RGBA:
   case GL_RGBA2:
   case GL_RGBA4:
   case GL_RGB5_A1:
   case GL_RGBA8:
   case GL_RGB10_A2:
   case GL_RGBA12:
   case GL_RGBA16:
      rb->Format = MESA_FORMAT_ARGB8888;
      rb->DataType = GL_UNSIGNED_BYTE;
      break;
   case GL_ALPHA:
   case GL_ALPHA8:
      rb->Format = MESA_FORMAT_A8;
      rb->DataType = GL_UNSIGNED_BYTE;
      break;
   case GL_STENCIL_INDEX:
   case GL_STENCIL_INDEX1_EXT:
   case GL_STENCIL_INDEX4_EXT:
   case GL_STENCIL_INDEX8_EXT:
   case GL_STENCIL_INDEX16_EXT:
      /* alloc a depth+stencil buffer */
      rb->Format = MESA_FORMAT_S8_Z24;
      rb->DataType = GL_UNSIGNED_INT_24_8_EXT;
      break;
   case GL_DEPTH_COMPONENT16:
      rb->Format = MESA_FORMAT_Z16;
      rb->DataType = GL_UNSIGNED_SHORT;
      break;
   case GL_DEPTH_COMPONENT:
   case GL_DEPTH_COMPONENT24:
   case GL_DEPTH_COMPONENT32:
      rb->Format = MESA_FORMAT_S8_Z24;
      rb->DataType = GL_UNSIGNED_INT_24_8_EXT;
      break;
   case GL_DEPTH_STENCIL_EXT:
   case GL_DEPTH24_STENCIL8_EXT:
      rb->Format = MESA_FORMAT_S8_Z24;
      rb->DataType = GL_UNSIGNED_INT_24_8_EXT;
      break;
   default:
      _mesa_problem(ctx,
                    "Unexpected format in intel_alloc_renderbuffer_storage");
      return GL_FALSE;
   }

   rb->_BaseFormat = _mesa_base_fbo_format(ctx, internalFormat);
   cpp = _mesa_get_format_bytes(rb->Format);

   intel_flush(ctx);

   /* free old region */
   if (irb->region) {
      intel_region_release(&irb->region);
   }

   /* allocate new memory region/renderbuffer */

   /* alloc hardware renderbuffer */
   DBG("Allocating %d x %d Intel RBO\n", width, height);

   irb->region = intel_region_alloc(intel, I915_TILING_NONE, cpp,
				    width, height, GL_TRUE);
   if (!irb->region)
      return GL_FALSE;       /* out of memory? */

   ASSERT(irb->region->buffer);

   rb->Width = width;
   rb->Height = height;

   return GL_TRUE;
}


#if FEATURE_OES_EGL_image
static void
intel_image_target_renderbuffer_storage(GLcontext *ctx,
					struct gl_renderbuffer *rb,
					void *image_handle)
{
   struct intel_context *intel = intel_context(ctx);
   struct intel_renderbuffer *irb;
   __DRIscreen *screen;
   __DRIimage *image;

   screen = intel->intelScreen->driScrnPriv;
   image = screen->dri2.image->lookupEGLImage(intel->driContext, image_handle,
					      intel->driContext->loaderPrivate);
   if (image == NULL)
      return;

   irb = intel_renderbuffer(rb);
   if (irb->region)
      intel_region_release(&irb->region);
   intel_region_reference(&irb->region, image->region);

   rb->InternalFormat = image->internal_format;
   rb->Width = image->region->width;
   rb->Height = image->region->height;
   rb->Format = image->format;
   rb->DataType = image->data_type;
   rb->_BaseFormat = _mesa_base_fbo_format(&intel->ctx,
					   image->internal_format);
}
#endif

/**
 * Called for each hardware renderbuffer when a _window_ is resized.
 * Just update fields.
 * Not used for user-created renderbuffers!
 */
static GLboolean
intel_alloc_window_storage(GLcontext * ctx, struct gl_renderbuffer *rb,
                           GLenum internalFormat, GLuint width, GLuint height)
{
   ASSERT(rb->Name == 0);
   rb->Width = width;
   rb->Height = height;
   rb->InternalFormat = internalFormat;

   return GL_TRUE;
}


static void
intel_resize_buffers(GLcontext *ctx, struct gl_framebuffer *fb,
		     GLuint width, GLuint height)
{
   int i;

   _mesa_resize_framebuffer(ctx, fb, width, height);

   fb->Initialized = GL_TRUE; /* XXX remove someday */

   if (fb->Name != 0) {
      return;
   }


   /* Make sure all window system renderbuffers are up to date */
   for (i = BUFFER_FRONT_LEFT; i <= BUFFER_BACK_RIGHT; i++) {
      struct gl_renderbuffer *rb = fb->Attachment[i].Renderbuffer;

      /* only resize if size is changing */
      if (rb && (rb->Width != width || rb->Height != height)) {
	 rb->AllocStorage(ctx, rb, rb->InternalFormat, width, height);
      }
   }
}


/** Dummy function for gl_renderbuffer::AllocStorage() */
static GLboolean
intel_nop_alloc_storage(GLcontext * ctx, struct gl_renderbuffer *rb,
                        GLenum internalFormat, GLuint width, GLuint height)
{
   _mesa_problem(ctx, "intel_op_alloc_storage should never be called.");
   return GL_FALSE;
}


void
intel_renderbuffer_set_region(struct intel_context *intel,
			      struct intel_renderbuffer *rb,
			      struct intel_region *region)
{
   struct intel_region *old;

   old = rb->region;
   rb->region = NULL;
   intel_region_reference(&rb->region, region);
   intel_region_release(&old);
}


/**
 * Create a new intel_renderbuffer which corresponds to an on-screen window,
 * not a user-created renderbuffer.
 */
struct intel_renderbuffer *
intel_create_renderbuffer(gl_format format)
{
   GET_CURRENT_CONTEXT(ctx);

   struct intel_renderbuffer *irb;

   irb = CALLOC_STRUCT(intel_renderbuffer);
   if (!irb) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "creating renderbuffer");
      return NULL;
   }

   _mesa_init_renderbuffer(&irb->Base, 0);
   irb->Base.ClassID = INTEL_RB_CLASS;

   switch (format) {
   case MESA_FORMAT_RGB565:
      irb->Base._BaseFormat = GL_RGB;
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      break;
   case MESA_FORMAT_XRGB8888:
      irb->Base._BaseFormat = GL_RGB;
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      break;
   case MESA_FORMAT_ARGB8888:
      irb->Base._BaseFormat = GL_RGBA;
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      break;
   case MESA_FORMAT_Z16:
      irb->Base._BaseFormat = GL_DEPTH_COMPONENT;
      irb->Base.DataType = GL_UNSIGNED_SHORT;
      break;
   case MESA_FORMAT_X8_Z24:
      irb->Base._BaseFormat = GL_DEPTH_COMPONENT;
      irb->Base.DataType = GL_UNSIGNED_INT;
      break;
   case MESA_FORMAT_S8_Z24:
      irb->Base._BaseFormat = GL_DEPTH_STENCIL;
      irb->Base.DataType = GL_UNSIGNED_INT_24_8_EXT;
      break;
   case MESA_FORMAT_A8:
      irb->Base._BaseFormat = GL_ALPHA;
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      break;
   default:
      _mesa_problem(NULL,
                    "Unexpected intFormat in intel_create_renderbuffer");
      free(irb);
      return NULL;
   }

   irb->Base.Format = format;
   irb->Base.InternalFormat = irb->Base._BaseFormat;

   /* intel-specific methods */
   irb->Base.Delete = intel_delete_renderbuffer;
   irb->Base.AllocStorage = intel_alloc_window_storage;
   irb->Base.GetPointer = intel_get_pointer;

   return irb;
}


/**
 * Create a new renderbuffer object.
 * Typically called via glBindRenderbufferEXT().
 */
static struct gl_renderbuffer *
intel_new_renderbuffer(GLcontext * ctx, GLuint name)
{
   /*struct intel_context *intel = intel_context(ctx); */
   struct intel_renderbuffer *irb;

   irb = CALLOC_STRUCT(intel_renderbuffer);
   if (!irb) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "creating renderbuffer");
      return NULL;
   }

   _mesa_init_renderbuffer(&irb->Base, name);
   irb->Base.ClassID = INTEL_RB_CLASS;

   /* intel-specific methods */
   irb->Base.Delete = intel_delete_renderbuffer;
   irb->Base.AllocStorage = intel_alloc_renderbuffer_storage;
   irb->Base.GetPointer = intel_get_pointer;
   /* span routines set in alloc_storage function */

   return &irb->Base;
}


/**
 * Called via glBindFramebufferEXT().
 */
static void
intel_bind_framebuffer(GLcontext * ctx, GLenum target,
                       struct gl_framebuffer *fb, struct gl_framebuffer *fbread)
{
   if (target == GL_FRAMEBUFFER_EXT || target == GL_DRAW_FRAMEBUFFER_EXT) {
      intel_draw_buffer(ctx, fb);
   }
   else {
      /* don't need to do anything if target == GL_READ_FRAMEBUFFER_EXT */
   }
}


/**
 * Called via glFramebufferRenderbufferEXT().
 */
static void
intel_framebuffer_renderbuffer(GLcontext * ctx,
                               struct gl_framebuffer *fb,
                               GLenum attachment, struct gl_renderbuffer *rb)
{
   DBG("Intel FramebufferRenderbuffer %u %u\n", fb->Name, rb ? rb->Name : 0);

   intel_flush(ctx);

   _mesa_framebuffer_renderbuffer(ctx, fb, attachment, rb);
   intel_draw_buffer(ctx, fb);
}


static GLboolean
intel_update_wrapper(GLcontext *ctx, struct intel_renderbuffer *irb, 
		     struct gl_texture_image *texImage)
{
   if (texImage->TexFormat == MESA_FORMAT_ARGB8888) {
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      DBG("Render to RGBA8 texture OK\n");
   }
   else if (texImage->TexFormat == MESA_FORMAT_XRGB8888) {
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      DBG("Render to XGBA8 texture OK\n");
   }
   else if (texImage->TexFormat == MESA_FORMAT_RGB565) {
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      DBG("Render to RGB5 texture OK\n");
   }
   else if (texImage->TexFormat == MESA_FORMAT_ARGB1555) {
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      DBG("Render to ARGB1555 texture OK\n");
   }
   else if (texImage->TexFormat == MESA_FORMAT_ARGB4444) {
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      DBG("Render to ARGB4444 texture OK\n");
   }
   else if (texImage->TexFormat == MESA_FORMAT_A8) {
      irb->Base.DataType = GL_UNSIGNED_BYTE;
      DBG("Render to A8 texture OK\n");
   }
   else if (texImage->TexFormat == MESA_FORMAT_Z16) {
      irb->Base.DataType = GL_UNSIGNED_SHORT;
      DBG("Render to DEPTH16 texture OK\n");
   }
   else if (texImage->TexFormat == MESA_FORMAT_S8_Z24) {
      irb->Base.DataType = GL_UNSIGNED_INT_24_8_EXT;
      DBG("Render to DEPTH_STENCIL texture OK\n");
   }
   else {
      DBG("Render to texture BAD FORMAT %s\n",
	  _mesa_get_format_name(texImage->TexFormat));
      return GL_FALSE;
   }

   irb->Base.Format = texImage->TexFormat;

   irb->Base.InternalFormat = texImage->InternalFormat;
   irb->Base._BaseFormat = _mesa_base_fbo_format(ctx, irb->Base.InternalFormat);
   irb->Base.Width = texImage->Width;
   irb->Base.Height = texImage->Height;

   irb->Base.Delete = intel_delete_renderbuffer;
   irb->Base.AllocStorage = intel_nop_alloc_storage;

   return GL_TRUE;
}


/**
 * When glFramebufferTexture[123]D is called this function sets up the
 * gl_renderbuffer wrapper around the texture image.
 * This will have the region info needed for hardware rendering.
 */
static struct intel_renderbuffer *
intel_wrap_texture(GLcontext * ctx, struct gl_texture_image *texImage)
{
   const GLuint name = ~0;   /* not significant, but distinct for debugging */
   struct intel_renderbuffer *irb;

   /* make an intel_renderbuffer to wrap the texture image */
   irb = CALLOC_STRUCT(intel_renderbuffer);
   if (!irb) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glFramebufferTexture");
      return NULL;
   }

   _mesa_init_renderbuffer(&irb->Base, name);
   irb->Base.ClassID = INTEL_RB_CLASS;

   if (!intel_update_wrapper(ctx, irb, texImage)) {
      free(irb);
      return NULL;
   }

   return irb;
}


/**
 * Called by glFramebufferTexture[123]DEXT() (and other places) to
 * prepare for rendering into texture memory.  This might be called
 * many times to choose different texture levels, cube faces, etc
 * before intel_finish_render_texture() is ever called.
 */
static void
intel_render_texture(GLcontext * ctx,
                     struct gl_framebuffer *fb,
                     struct gl_renderbuffer_attachment *att)
{
   struct gl_texture_image *newImage
      = att->Texture->Image[att->CubeMapFace][att->TextureLevel];
   struct intel_renderbuffer *irb = intel_renderbuffer(att->Renderbuffer);
   struct intel_texture_image *intel_image;
   GLuint dst_x, dst_y;

   (void) fb;

   ASSERT(newImage);

   intel_image = intel_texture_image(newImage);
   if (!intel_image->mt) {
      /* Fallback on drawing to a texture that doesn't have a miptree
       * (has a border, width/height 0, etc.)
       */
      _mesa_reference_renderbuffer(&att->Renderbuffer, NULL);
      _mesa_render_texture(ctx, fb, att);
      return;
   }
   else if (!irb) {
      irb = intel_wrap_texture(ctx, newImage);
      if (irb) {
         /* bind the wrapper to the attachment point */
         _mesa_reference_renderbuffer(&att->Renderbuffer, &irb->Base);
      }
      else {
         /* fallback to software rendering */
         _mesa_render_texture(ctx, fb, att);
         return;
      }
   }

   if (!intel_update_wrapper(ctx, irb, newImage)) {
       _mesa_reference_renderbuffer(&att->Renderbuffer, NULL);
       _mesa_render_texture(ctx, fb, att);
       return;
   }

   DBG("Begin render texture tid %lx tex=%u w=%d h=%d refcount=%d\n",
       _glthread_GetID(),
       att->Texture->Name, newImage->Width, newImage->Height,
       irb->Base.RefCount);

   /* point the renderbufer's region to the texture image region */
   if (irb->region != intel_image->mt->region) {
      if (irb->region)
	 intel_region_release(&irb->region);
      intel_region_reference(&irb->region, intel_image->mt->region);
   }

   /* compute offset of the particular 2D image within the texture region */
   intel_miptree_get_image_offset(intel_image->mt,
				  att->TextureLevel,
				  att->CubeMapFace,
				  att->Zoffset,
				  &dst_x, &dst_y);

   intel_image->mt->region->draw_offset = (dst_y * intel_image->mt->region->pitch +
					   dst_x) * intel_image->mt->cpp;
   intel_image->mt->region->draw_x = dst_x;
   intel_image->mt->region->draw_y = dst_y;
   intel_image->used_as_render_target = GL_TRUE;

   /* update drawing region, etc */
   intel_draw_buffer(ctx, fb);
}


/**
 * Called by Mesa when rendering to a texture is done.
 */
static void
intel_finish_render_texture(GLcontext * ctx,
                            struct gl_renderbuffer_attachment *att)
{
   struct intel_context *intel = intel_context(ctx);
   struct gl_texture_object *tex_obj = att->Texture;
   struct gl_texture_image *image =
      tex_obj->Image[att->CubeMapFace][att->TextureLevel];
   struct intel_texture_image *intel_image = intel_texture_image(image);

   /* Flag that this image may now be validated into the object's miptree. */
   intel_image->used_as_render_target = GL_FALSE;

   /* Since we've (probably) rendered to the texture and will (likely) use
    * it in the texture domain later on in this batchbuffer, flush the
    * batch.  Once again, we wish for a domain tracker in libdrm to cover
    * usage inside of a batchbuffer like GEM does in the kernel.
    */
   intel_batchbuffer_emit_mi_flush(intel->batch);
}

/**
 * Do additional "completeness" testing of a framebuffer object.
 */
static void
intel_validate_framebuffer(GLcontext *ctx, struct gl_framebuffer *fb)
{
   const struct intel_renderbuffer *depthRb =
      intel_get_renderbuffer(fb, BUFFER_DEPTH);
   const struct intel_renderbuffer *stencilRb =
      intel_get_renderbuffer(fb, BUFFER_STENCIL);
   int i;

   if (depthRb && stencilRb && stencilRb != depthRb) {
      if (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Type == GL_TEXTURE &&
	  ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Type == GL_TEXTURE &&
	  (ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Texture->Name ==
	   ctx->DrawBuffer->Attachment[BUFFER_STENCIL].Texture->Name)) {
	 /* OK */
      } else {
	 /* we only support combined depth/stencil buffers, not separate
	  * stencil buffers.
	  */
	 DBG("Only supports combined depth/stencil (found %s, %s)\n",
	     depthRb ? _mesa_get_format_name(depthRb->Base.Format): "NULL",
	     stencilRb ? _mesa_get_format_name(stencilRb->Base.Format): "NULL");
	 fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
      }
   }

   for (i = 0; i < ctx->Const.MaxDrawBuffers; i++) {
      struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[i];
      struct intel_renderbuffer *irb = intel_renderbuffer(rb);

      if (rb == NULL)
	 continue;

      if (irb == NULL) {
	 DBG("software rendering renderbuffer\n");
	 fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
	 continue;
      }

      switch (irb->Base.Format) {
      case MESA_FORMAT_ARGB8888:
      case MESA_FORMAT_XRGB8888:
      case MESA_FORMAT_RGB565:
      case MESA_FORMAT_ARGB1555:
      case MESA_FORMAT_ARGB4444:
      case MESA_FORMAT_A8:
	 break;
      default:
	 fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;
      }
   }
}


/**
 * Do one-time context initializations related to GL_EXT_framebuffer_object.
 * Hook in device driver functions.
 */
void
intel_fbo_init(struct intel_context *intel)
{
   intel->ctx.Driver.NewFramebuffer = intel_new_framebuffer;
   intel->ctx.Driver.NewRenderbuffer = intel_new_renderbuffer;
   intel->ctx.Driver.BindFramebuffer = intel_bind_framebuffer;
   intel->ctx.Driver.FramebufferRenderbuffer = intel_framebuffer_renderbuffer;
   intel->ctx.Driver.RenderTexture = intel_render_texture;
   intel->ctx.Driver.FinishRenderTexture = intel_finish_render_texture;
   intel->ctx.Driver.ResizeBuffers = intel_resize_buffers;
   intel->ctx.Driver.ValidateFramebuffer = intel_validate_framebuffer;
   intel->ctx.Driver.BlitFramebuffer = _mesa_meta_BlitFramebuffer;

#if FEATURE_OES_EGL_image
   intel->ctx.Driver.EGLImageTargetRenderbufferStorage =
      intel_image_target_renderbuffer_storage;
#endif   
}