2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
27 * Functions for allocating/managing framebuffers and renderbuffers.
28 * Also, routines for reading/writing renderbuffer data as ubytes,
29 * ushorts, uints, etc.
36 #include "depthstencil.h"
39 #include "framebuffer.h"
40 #include "renderbuffer.h"
45 * Compute/set the _DepthMax field for the given framebuffer.
46 * This value depends on the Z buffer resolution.
49 compute_depth_max(struct gl_framebuffer
*fb
)
51 if (fb
->Visual
.depthBits
== 0) {
52 /* Special case. Even if we don't have a depth buffer we need
53 * good values for DepthMax for Z vertex transformation purposes
54 * and for per-fragment fog computation.
56 fb
->_DepthMax
= (1 << 16) - 1;
58 else if (fb
->Visual
.depthBits
< 32) {
59 fb
->_DepthMax
= (1 << fb
->Visual
.depthBits
) - 1;
62 /* Special case since shift values greater than or equal to the
63 * number of bits in the left hand expression's type are undefined.
65 fb
->_DepthMax
= 0xffffffff;
67 fb
->_DepthMaxF
= (GLfloat
) fb
->_DepthMax
;
69 /* Minimum resolvable depth value, for polygon offset */
70 fb
->_MRD
= 1.0 / fb
->_DepthMaxF
;
75 * Create and initialize a gl_framebuffer object.
76 * This is intended for creating _window_system_ framebuffers, not generic
77 * framebuffer objects ala GL_EXT_framebuffer_object.
79 * \sa _mesa_new_framebuffer
81 struct gl_framebuffer
*
82 _mesa_create_framebuffer(const GLvisual
*visual
)
84 struct gl_framebuffer
*fb
= CALLOC_STRUCT(gl_framebuffer
);
87 _mesa_initialize_framebuffer(fb
, visual
);
94 * Allocate a new gl_framebuffer object.
95 * This is the default function for ctx->Driver.NewFramebuffer().
96 * This is for allocating user-created framebuffers, not window-system
98 * \sa _mesa_create_framebuffer
100 struct gl_framebuffer
*
101 _mesa_new_framebuffer(GLcontext
*ctx
, GLuint name
)
103 struct gl_framebuffer
*fb
;
106 fb
= CALLOC_STRUCT(gl_framebuffer
);
110 fb
->ColorDrawBuffer
[0] = GL_COLOR_ATTACHMENT0_EXT
;
111 fb
->_ColorDrawBufferMask
[0] = BUFFER_BIT_COLOR0
;
112 fb
->ColorReadBuffer
= GL_COLOR_ATTACHMENT0_EXT
;
113 fb
->_ColorReadBufferIndex
= BUFFER_COLOR0
;
114 fb
->Delete
= _mesa_destroy_framebuffer
;
121 * Initialize a gl_framebuffer object. Typically used to initialize
122 * window system-created framebuffers, not user-created framebuffers.
123 * \sa _mesa_create_framebuffer
126 _mesa_initialize_framebuffer(struct gl_framebuffer
*fb
, const GLvisual
*visual
)
131 _mesa_bzero(fb
, sizeof(struct gl_framebuffer
));
133 _glthread_INIT_MUTEX(fb
->Mutex
);
137 /* save the visual */
138 fb
->Visual
= *visual
;
140 /* Init glRead/DrawBuffer state */
141 if (visual
->doubleBufferMode
) {
142 fb
->ColorDrawBuffer
[0] = GL_BACK
;
143 fb
->_ColorDrawBufferMask
[0] = BUFFER_BIT_BACK_LEFT
;
144 fb
->ColorReadBuffer
= GL_BACK
;
145 fb
->_ColorReadBufferIndex
= BUFFER_BACK_LEFT
;
148 fb
->ColorDrawBuffer
[0] = GL_FRONT
;
149 fb
->_ColorDrawBufferMask
[0] = BUFFER_BIT_FRONT_LEFT
;
150 fb
->ColorReadBuffer
= GL_FRONT
;
151 fb
->_ColorReadBufferIndex
= BUFFER_FRONT_LEFT
;
154 fb
->Delete
= _mesa_destroy_framebuffer
;
155 fb
->_Status
= GL_FRAMEBUFFER_COMPLETE_EXT
;
157 compute_depth_max(fb
);
162 * Deallocate buffer and everything attached to it.
163 * Typically called via the gl_framebuffer->Delete() method.
166 _mesa_destroy_framebuffer(struct gl_framebuffer
*fb
)
169 _mesa_free_framebuffer_data(fb
);
176 * Free all the data hanging off the given gl_framebuffer, but don't free
177 * the gl_framebuffer object itself.
180 _mesa_free_framebuffer_data(struct gl_framebuffer
*fb
)
185 assert(fb
->RefCount
== 0);
187 _glthread_DESTROY_MUTEX(fb
->Mutex
);
189 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
190 struct gl_renderbuffer_attachment
*att
= &fb
->Attachment
[i
];
191 if (att
->Renderbuffer
) {
192 _mesa_reference_renderbuffer(&att
->Renderbuffer
, NULL
);
195 /* render to texture */
196 att
->Texture
->RefCount
--;
197 if (att
->Texture
->RefCount
== 0) {
198 GET_CURRENT_CONTEXT(ctx
);
200 ctx
->Driver
.DeleteTexture(ctx
, att
->Texture
);
208 /* unbind _Depth/_StencilBuffer to decr ref counts */
209 _mesa_reference_renderbuffer(&fb
->_DepthBuffer
, NULL
);
210 _mesa_reference_renderbuffer(&fb
->_StencilBuffer
, NULL
);
215 * Set *ptr to point to fb, with refcounting and locking.
218 _mesa_reference_framebuffer(struct gl_framebuffer
**ptr
,
219 struct gl_framebuffer
*fb
)
227 _mesa_unreference_framebuffer(ptr
);
231 _glthread_LOCK_MUTEX(fb
->Mutex
);
233 _glthread_UNLOCK_MUTEX(fb
->Mutex
);
239 * Undo/remove a reference to a framebuffer object.
240 * Decrement the framebuffer object's reference count and delete it when
241 * the refcount hits zero.
242 * Note: we pass the address of a pointer and set it to NULL.
245 _mesa_unreference_framebuffer(struct gl_framebuffer
**fb
)
249 GLboolean deleteFlag
= GL_FALSE
;
251 _glthread_LOCK_MUTEX((*fb
)->Mutex
);
252 ASSERT((*fb
)->RefCount
> 0);
254 deleteFlag
= ((*fb
)->RefCount
== 0);
255 _glthread_UNLOCK_MUTEX((*fb
)->Mutex
);
268 * Resize the given framebuffer's renderbuffers to the new width and height.
269 * This should only be used for window-system framebuffers, not
270 * user-created renderbuffers (i.e. made with GL_EXT_framebuffer_object).
271 * This will typically be called via ctx->Driver.ResizeBuffers() or directly
272 * from a device driver.
274 * \note it's possible for ctx to be null since a window can be resized
275 * without a currently bound rendering context.
278 _mesa_resize_framebuffer(GLcontext
*ctx
, struct gl_framebuffer
*fb
,
279 GLuint width
, GLuint height
)
283 /* XXX I think we could check if the size is not changing
287 /* For window system framebuffers, Name is zero */
288 assert(fb
->Name
== 0);
290 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
291 struct gl_renderbuffer_attachment
*att
= &fb
->Attachment
[i
];
292 if (att
->Type
== GL_RENDERBUFFER_EXT
&& att
->Renderbuffer
) {
293 struct gl_renderbuffer
*rb
= att
->Renderbuffer
;
294 /* only resize if size is changing */
295 if (rb
->Width
!= width
|| rb
->Height
!= height
) {
296 /* could just as well pass rb->_ActualFormat here */
297 if (rb
->AllocStorage(ctx
, rb
, rb
->InternalFormat
, width
, height
)) {
298 ASSERT(rb
->Width
== width
);
299 ASSERT(rb
->Height
== height
);
302 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "Resizing framebuffer");
309 if (fb
->_DepthBuffer
) {
310 struct gl_renderbuffer
*rb
= fb
->_DepthBuffer
;
311 if (rb
->Width
!= width
|| rb
->Height
!= height
) {
312 if (!rb
->AllocStorage(ctx
, rb
, rb
->InternalFormat
, width
, height
)) {
313 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "Resizing framebuffer");
318 if (fb
->_StencilBuffer
) {
319 struct gl_renderbuffer
*rb
= fb
->_StencilBuffer
;
320 if (rb
->Width
!= width
|| rb
->Height
!= height
) {
321 if (!rb
->AllocStorage(ctx
, rb
, rb
->InternalFormat
, width
, height
)) {
322 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "Resizing framebuffer");
331 /* update scissor / window bounds */
332 _mesa_update_draw_buffer_bounds(ctx
);
333 /* Signal new buffer state so that swrast will update its clipping
334 * info (the CLIP_BIT flag).
336 ctx
->NewState
|= _NEW_BUFFERS
;
342 * Examine all the framebuffer's renderbuffers to update the Width/Height
343 * fields of the framebuffer. If we have renderbuffers with different
344 * sizes, set the framebuffer's width and height to zero.
345 * Note: this is only intended for user-created framebuffers, not
346 * window-system framebuffes.
349 update_framebuffer_size(struct gl_framebuffer
*fb
)
351 GLboolean haveSize
= GL_FALSE
;
354 /* user-created framebuffers only */
357 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
358 struct gl_renderbuffer_attachment
*att
= &fb
->Attachment
[i
];
359 const struct gl_renderbuffer
*rb
= att
->Renderbuffer
;
362 if (rb
->Width
!= fb
->Width
&& rb
->Height
!= fb
->Height
) {
370 fb
->Width
= rb
->Width
;
371 fb
->Height
= rb
->Height
;
380 * Update the context's current drawing buffer's Xmin, Xmax, Ymin, Ymax fields.
381 * These values are computed from the buffer's width and height and
382 * the scissor box, if it's enabled.
383 * \param ctx the GL context.
386 _mesa_update_draw_buffer_bounds(GLcontext
*ctx
)
388 struct gl_framebuffer
*buffer
= ctx
->DrawBuffer
;
394 /* user-created framebuffer size depends on the renderbuffers */
395 update_framebuffer_size(buffer
);
400 buffer
->_Xmax
= buffer
->Width
;
401 buffer
->_Ymax
= buffer
->Height
;
403 if (ctx
->Scissor
.Enabled
) {
404 if (ctx
->Scissor
.X
> buffer
->_Xmin
) {
405 buffer
->_Xmin
= ctx
->Scissor
.X
;
407 if (ctx
->Scissor
.Y
> buffer
->_Ymin
) {
408 buffer
->_Ymin
= ctx
->Scissor
.Y
;
410 if (ctx
->Scissor
.X
+ ctx
->Scissor
.Width
< buffer
->_Xmax
) {
411 buffer
->_Xmax
= ctx
->Scissor
.X
+ ctx
->Scissor
.Width
;
413 if (ctx
->Scissor
.Y
+ ctx
->Scissor
.Height
< buffer
->_Ymax
) {
414 buffer
->_Ymax
= ctx
->Scissor
.Y
+ ctx
->Scissor
.Height
;
416 /* finally, check for empty region */
417 if (buffer
->_Xmin
> buffer
->_Xmax
) {
418 buffer
->_Xmin
= buffer
->_Xmax
;
420 if (buffer
->_Ymin
> buffer
->_Ymax
) {
421 buffer
->_Ymin
= buffer
->_Ymax
;
425 ASSERT(buffer
->_Xmin
<= buffer
->_Xmax
);
426 ASSERT(buffer
->_Ymin
<= buffer
->_Ymax
);
431 * The glGet queries of the framebuffer red/green/blue size, stencil size,
432 * etc. are satisfied by the fields of ctx->DrawBuffer->Visual. These can
433 * change depending on the renderbuffer bindings. This function updates
434 * the given framebuffer's Visual from the current renderbuffer bindings.
436 * This may apply to user-created framebuffers or window system framebuffers.
438 * Also note: ctx->DrawBuffer->Visual.depthBits might not equal
439 * ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer.DepthBits.
440 * The former one is used to convert floating point depth values into
444 _mesa_update_framebuffer_visual(struct gl_framebuffer
*fb
)
448 _mesa_bzero(&fb
->Visual
, sizeof(fb
->Visual
));
449 fb
->Visual
.rgbMode
= GL_TRUE
; /* assume this */
451 #if 0 /* this _might_ be needed */
452 if (fb
->_Status
!= GL_FRAMEBUFFER_COMPLETE_EXT
) {
453 /* leave visual fields zero'd */
458 /* find first RGB or CI renderbuffer */
459 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
460 if (fb
->Attachment
[i
].Renderbuffer
) {
461 const struct gl_renderbuffer
*rb
= fb
->Attachment
[i
].Renderbuffer
;
462 if (rb
->_BaseFormat
== GL_RGBA
|| rb
->_BaseFormat
== GL_RGB
) {
463 fb
->Visual
.redBits
= rb
->RedBits
;
464 fb
->Visual
.greenBits
= rb
->GreenBits
;
465 fb
->Visual
.blueBits
= rb
->BlueBits
;
466 fb
->Visual
.alphaBits
= rb
->AlphaBits
;
467 fb
->Visual
.rgbBits
= fb
->Visual
.redBits
468 + fb
->Visual
.greenBits
+ fb
->Visual
.blueBits
;
469 fb
->Visual
.floatMode
= GL_FALSE
;
472 else if (rb
->_BaseFormat
== GL_COLOR_INDEX
) {
473 fb
->Visual
.indexBits
= rb
->IndexBits
;
474 fb
->Visual
.rgbMode
= GL_FALSE
;
480 if (fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
) {
481 fb
->Visual
.haveDepthBuffer
= GL_TRUE
;
483 = fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
->DepthBits
;
486 if (fb
->Attachment
[BUFFER_STENCIL
].Renderbuffer
) {
487 fb
->Visual
.haveStencilBuffer
= GL_TRUE
;
488 fb
->Visual
.stencilBits
489 = fb
->Attachment
[BUFFER_STENCIL
].Renderbuffer
->StencilBits
;
492 if (fb
->Attachment
[BUFFER_ACCUM
].Renderbuffer
) {
493 fb
->Visual
.haveAccumBuffer
= GL_TRUE
;
494 fb
->Visual
.accumRedBits
495 = fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
->RedBits
;
496 fb
->Visual
.accumGreenBits
497 = fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
->GreenBits
;
498 fb
->Visual
.accumBlueBits
499 = fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
->BlueBits
;
500 fb
->Visual
.accumAlphaBits
501 = fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
->AlphaBits
;
504 compute_depth_max(fb
);
509 * Update the framebuffer's _DepthBuffer field using the renderbuffer
510 * found at the given attachment index.
512 * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
513 * create and install a depth wrapper/adaptor.
515 * \param fb the framebuffer whose _DepthBuffer field to update
516 * \param attIndex indicates the renderbuffer to possibly wrap
519 _mesa_update_depth_buffer(GLcontext
*ctx
,
520 struct gl_framebuffer
*fb
,
523 struct gl_renderbuffer
*depthRb
;
525 /* only one possiblity for now */
526 ASSERT(attIndex
== BUFFER_DEPTH
);
528 depthRb
= fb
->Attachment
[attIndex
].Renderbuffer
;
530 if (depthRb
&& depthRb
->_ActualFormat
== GL_DEPTH24_STENCIL8_EXT
) {
531 /* The attached depth buffer is a GL_DEPTH_STENCIL renderbuffer */
532 if (!fb
->_DepthBuffer
533 || fb
->_DepthBuffer
->Wrapped
!= depthRb
534 || fb
->_DepthBuffer
->_BaseFormat
!= GL_DEPTH_COMPONENT
) {
535 /* need to update wrapper */
536 struct gl_renderbuffer
*wrapper
537 = _mesa_new_z24_renderbuffer_wrapper(ctx
, depthRb
);
538 _mesa_reference_renderbuffer(&fb
->_DepthBuffer
, wrapper
);
539 ASSERT(fb
->_DepthBuffer
->Wrapped
== depthRb
);
543 /* depthRb may be null */
544 _mesa_reference_renderbuffer(&fb
->_DepthBuffer
, depthRb
);
550 * Update the framebuffer's _StencilBuffer field using the renderbuffer
551 * found at the given attachment index.
553 * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
554 * create and install a stencil wrapper/adaptor.
556 * \param fb the framebuffer whose _StencilBuffer field to update
557 * \param attIndex indicates the renderbuffer to possibly wrap
560 _mesa_update_stencil_buffer(GLcontext
*ctx
,
561 struct gl_framebuffer
*fb
,
564 struct gl_renderbuffer
*stencilRb
;
566 ASSERT(attIndex
== BUFFER_DEPTH
||
567 attIndex
== BUFFER_STENCIL
);
569 stencilRb
= fb
->Attachment
[attIndex
].Renderbuffer
;
571 if (stencilRb
&& stencilRb
->_ActualFormat
== GL_DEPTH24_STENCIL8_EXT
) {
572 /* The attached stencil buffer is a GL_DEPTH_STENCIL renderbuffer */
573 if (!fb
->_StencilBuffer
574 || fb
->_StencilBuffer
->Wrapped
!= stencilRb
575 || fb
->_StencilBuffer
->_BaseFormat
!= GL_STENCIL_INDEX
) {
576 /* need to update wrapper */
577 struct gl_renderbuffer
*wrapper
578 = _mesa_new_s8_renderbuffer_wrapper(ctx
, stencilRb
);
579 _mesa_reference_renderbuffer(&fb
->_StencilBuffer
, wrapper
);
580 ASSERT(fb
->_StencilBuffer
->Wrapped
== stencilRb
);
584 /* stencilRb may be null */
585 _mesa_reference_renderbuffer(&fb
->_StencilBuffer
, stencilRb
);
591 * Update the list of color drawing renderbuffer pointers.
592 * Later, when we're rendering we'll loop from 0 to _NumColorDrawBuffers
596 update_color_draw_buffers(GLcontext
*ctx
, struct gl_framebuffer
*fb
)
601 * Fragment programs can write to multiple colorbuffers with
602 * the GL_ARB_draw_buffers extension.
604 for (output
= 0; output
< ctx
->Const
.MaxDrawBuffers
; output
++) {
605 GLbitfield bufferMask
= fb
->_ColorDrawBufferMask
[output
];
608 if (!fb
->DeletePending
) {
609 /* We need the inner loop here because glDrawBuffer(GL_FRONT_AND_BACK)
610 * can specify writing to two or four color buffers (for example).
612 for (i
= 0; bufferMask
&& i
< BUFFER_COUNT
; i
++) {
613 const GLuint bufferBit
= 1 << i
;
614 if (bufferBit
& bufferMask
) {
615 struct gl_renderbuffer
*rb
= fb
->Attachment
[i
].Renderbuffer
;
616 if (rb
&& rb
->Width
> 0 && rb
->Height
> 0) {
617 fb
->_ColorDrawBuffers
[output
][count
] = rb
;
622 _mesa_warning(ctx, "DrawBuffer names a missing buffer!\n");
625 bufferMask
&= ~bufferBit
;
629 fb
->_NumColorDrawBuffers
[output
] = count
;
635 * Update the color read renderbuffer pointer.
636 * Unlike the DrawBuffer, we can only read from one (or zero) color buffers.
639 update_color_read_buffer(GLcontext
*ctx
, struct gl_framebuffer
*fb
)
642 if (fb
->_ColorReadBufferIndex
== -1 ||
646 fb
->_ColorReadBuffer
= NULL
; /* legal! */
649 ASSERT(fb
->_ColorReadBufferIndex
>= 0);
650 ASSERT(fb
->_ColorReadBufferIndex
< BUFFER_COUNT
);
652 = fb
->Attachment
[fb
->_ColorReadBufferIndex
].Renderbuffer
;
658 update_framebuffer(GLcontext
*ctx
, struct gl_framebuffer
*fb
)
660 /* Completeness only matters for user-created framebuffers */
662 /* XXX: EXT_framebuffer_blit:
663 framebuffer must still be complete wrt read/draw? */
664 _mesa_test_framebuffer_completeness(ctx
, fb
);
665 _mesa_update_framebuffer_visual(fb
);
668 /* update_color_draw/read_buffers not needed for
669 read/draw only fb, but shouldn't hurt ??? */
670 update_color_draw_buffers(ctx
, fb
);
671 update_color_read_buffer(ctx
, fb
);
672 _mesa_update_depth_buffer(ctx
, fb
, BUFFER_DEPTH
);
673 _mesa_update_stencil_buffer(ctx
, fb
, BUFFER_STENCIL
);
675 compute_depth_max(fb
);
679 * Update state related to the current draw/read framebuffers.
680 * Specifically, update these framebuffer fields:
682 * _NumColorDrawBuffers
686 * If the current framebuffer is user-created, make sure it's complete.
687 * The following functions can effect this state: glReadBuffer,
688 * glDrawBuffer, glDrawBuffersARB, glFramebufferRenderbufferEXT,
689 * glRenderbufferStorageEXT.
692 _mesa_update_framebuffer(GLcontext
*ctx
)
694 struct gl_framebuffer
*fb
= ctx
->DrawBuffer
;
695 struct gl_framebuffer
*fbread
= ctx
->ReadBuffer
;
697 update_framebuffer(ctx
, fb
);
698 if (fbread
!= fb
&& fbread
!= NULL
/* can happen at make_current -
699 core/driver circular dependencies, should be fixed up */)
700 update_framebuffer(ctx
, fbread
);
705 * Check if the renderbuffer for a read operation (glReadPixels, glCopyPixels,
706 * glCopyTex[Sub]Image, etc. exists.
707 * \param format a basic image format such as GL_RGB, GL_RGBA, GL_ALPHA,
708 * GL_DEPTH_COMPONENT, etc. or GL_COLOR, GL_DEPTH, GL_STENCIL.
709 * \return GL_TRUE if buffer exists, GL_FALSE otherwise
712 _mesa_source_buffer_exists(GLcontext
*ctx
, GLenum format
)
714 const struct gl_renderbuffer_attachment
*att
715 = ctx
->ReadBuffer
->Attachment
;
717 if (ctx
->ReadBuffer
->_Status
!= GL_FRAMEBUFFER_COMPLETE_EXT
) {
728 case GL_LUMINANCE_ALPHA
:
736 if (ctx
->ReadBuffer
->_ColorReadBuffer
== NULL
) {
739 /* XXX enable this post 6.5 release:
740 ASSERT(ctx->ReadBuffer->_ColorReadBuffer->RedBits > 0 ||
741 ctx->ReadBuffer->_ColorReadBuffer->IndexBits > 0);
745 case GL_DEPTH_COMPONENT
:
746 if (!att
[BUFFER_DEPTH
].Renderbuffer
) {
749 ASSERT(att
[BUFFER_DEPTH
].Renderbuffer
->DepthBits
> 0);
752 case GL_STENCIL_INDEX
:
753 if (!att
[BUFFER_STENCIL
].Renderbuffer
) {
756 ASSERT(att
[BUFFER_STENCIL
].Renderbuffer
->StencilBits
> 0);
758 case GL_DEPTH_STENCIL_EXT
:
759 if (!att
[BUFFER_DEPTH
].Renderbuffer
||
760 !att
[BUFFER_STENCIL
].Renderbuffer
) {
763 ASSERT(att
[BUFFER_DEPTH
].Renderbuffer
->DepthBits
> 0);
764 ASSERT(att
[BUFFER_STENCIL
].Renderbuffer
->StencilBits
> 0);
768 "Unexpected format 0x%x in _mesa_source_buffer_exists",
779 * As above, but for drawing operations.
780 * XXX code do some code merging w/ above function.
783 _mesa_dest_buffer_exists(GLcontext
*ctx
, GLenum format
)
785 const struct gl_renderbuffer_attachment
*att
786 = ctx
->ReadBuffer
->Attachment
;
788 if (ctx
->DrawBuffer
->_Status
!= GL_FRAMEBUFFER_COMPLETE_EXT
) {
799 case GL_LUMINANCE_ALPHA
:
807 /* nothing special */
808 /* Could assert that colorbuffer has RedBits > 0 */
811 case GL_DEPTH_COMPONENT
:
812 if (!att
[BUFFER_DEPTH
].Renderbuffer
) {
815 ASSERT(att
[BUFFER_DEPTH
].Renderbuffer
->DepthBits
> 0);
818 case GL_STENCIL_INDEX
:
819 if (!att
[BUFFER_STENCIL
].Renderbuffer
) {
822 ASSERT(att
[BUFFER_STENCIL
].Renderbuffer
->StencilBits
> 0);
824 case GL_DEPTH_STENCIL_EXT
:
825 if (!att
[BUFFER_DEPTH
].Renderbuffer
||
826 !att
[BUFFER_STENCIL
].Renderbuffer
) {
829 ASSERT(att
[BUFFER_DEPTH
].Renderbuffer
->DepthBits
> 0);
830 ASSERT(att
[BUFFER_STENCIL
].Renderbuffer
->StencilBits
> 0);
834 "Unexpected format 0x%x in _mesa_source_buffer_exists",