2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2008 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.
37 #include "depthstencil.h"
43 #include "framebuffer.h"
44 #include "renderbuffer.h"
50 * Compute/set the _DepthMax field for the given framebuffer.
51 * This value depends on the Z buffer resolution.
54 compute_depth_max(struct gl_framebuffer
*fb
)
56 if (fb
->Visual
.depthBits
== 0) {
57 /* Special case. Even if we don't have a depth buffer we need
58 * good values for DepthMax for Z vertex transformation purposes
59 * and for per-fragment fog computation.
61 fb
->_DepthMax
= (1 << 16) - 1;
63 else if (fb
->Visual
.depthBits
< 32) {
64 fb
->_DepthMax
= (1 << fb
->Visual
.depthBits
) - 1;
67 /* Special case since shift values greater than or equal to the
68 * number of bits in the left hand expression's type are undefined.
70 fb
->_DepthMax
= 0xffffffff;
72 fb
->_DepthMaxF
= (GLfloat
) fb
->_DepthMax
;
74 /* Minimum resolvable depth value, for polygon offset */
75 fb
->_MRD
= (GLfloat
)1.0 / fb
->_DepthMaxF
;
80 * Create and initialize a gl_framebuffer object.
81 * This is intended for creating _window_system_ framebuffers, not generic
82 * framebuffer objects ala GL_EXT_framebuffer_object.
84 * \sa _mesa_new_framebuffer
86 struct gl_framebuffer
*
87 _mesa_create_framebuffer(const GLvisual
*visual
)
89 struct gl_framebuffer
*fb
= CALLOC_STRUCT(gl_framebuffer
);
92 _mesa_initialize_window_framebuffer(fb
, visual
);
99 * Allocate a new gl_framebuffer object.
100 * This is the default function for ctx->Driver.NewFramebuffer().
101 * This is for allocating user-created framebuffers, not window-system
103 * \sa _mesa_create_framebuffer
105 struct gl_framebuffer
*
106 _mesa_new_framebuffer(GLcontext
*ctx
, GLuint name
)
108 struct gl_framebuffer
*fb
;
111 fb
= CALLOC_STRUCT(gl_framebuffer
);
113 _mesa_initialize_user_framebuffer(fb
, name
);
120 * Initialize a gl_framebuffer object. Typically used to initialize
121 * window system-created framebuffers, not user-created framebuffers.
122 * \sa _mesa_initialize_user_framebuffer
125 _mesa_initialize_window_framebuffer(struct gl_framebuffer
*fb
,
126 const GLvisual
*visual
)
131 memset(fb
, 0, sizeof(struct gl_framebuffer
));
133 _glthread_INIT_MUTEX(fb
->Mutex
);
137 /* save the visual */
138 fb
->Visual
= *visual
;
140 /* Init read/draw renderbuffer state */
141 if (visual
->doubleBufferMode
) {
142 fb
->_NumColorDrawBuffers
= 1;
143 fb
->ColorDrawBuffer
[0] = GL_BACK
;
144 fb
->_ColorDrawBufferIndexes
[0] = BUFFER_BACK_LEFT
;
145 fb
->ColorReadBuffer
= GL_BACK
;
146 fb
->_ColorReadBufferIndex
= BUFFER_BACK_LEFT
;
149 fb
->_NumColorDrawBuffers
= 1;
150 fb
->ColorDrawBuffer
[0] = GL_FRONT
;
151 fb
->_ColorDrawBufferIndexes
[0] = BUFFER_FRONT_LEFT
;
152 fb
->ColorReadBuffer
= GL_FRONT
;
153 fb
->_ColorReadBufferIndex
= BUFFER_FRONT_LEFT
;
156 fb
->Delete
= _mesa_destroy_framebuffer
;
157 fb
->_Status
= GL_FRAMEBUFFER_COMPLETE_EXT
;
159 compute_depth_max(fb
);
164 * Initialize a user-created gl_framebuffer object.
165 * \sa _mesa_initialize_window_framebuffer
168 _mesa_initialize_user_framebuffer(struct gl_framebuffer
*fb
, GLuint name
)
173 memset(fb
, 0, sizeof(struct gl_framebuffer
));
177 fb
->_NumColorDrawBuffers
= 1;
178 fb
->ColorDrawBuffer
[0] = GL_COLOR_ATTACHMENT0_EXT
;
179 fb
->_ColorDrawBufferIndexes
[0] = BUFFER_COLOR0
;
180 fb
->ColorReadBuffer
= GL_COLOR_ATTACHMENT0_EXT
;
181 fb
->_ColorReadBufferIndex
= BUFFER_COLOR0
;
182 fb
->Delete
= _mesa_destroy_framebuffer
;
183 _glthread_INIT_MUTEX(fb
->Mutex
);
188 * Deallocate buffer and everything attached to it.
189 * Typically called via the gl_framebuffer->Delete() method.
192 _mesa_destroy_framebuffer(struct gl_framebuffer
*fb
)
195 _mesa_free_framebuffer_data(fb
);
202 * Free all the data hanging off the given gl_framebuffer, but don't free
203 * the gl_framebuffer object itself.
206 _mesa_free_framebuffer_data(struct gl_framebuffer
*fb
)
211 assert(fb
->RefCount
== 0);
213 _glthread_DESTROY_MUTEX(fb
->Mutex
);
215 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
216 struct gl_renderbuffer_attachment
*att
= &fb
->Attachment
[i
];
217 if (att
->Renderbuffer
) {
218 _mesa_reference_renderbuffer(&att
->Renderbuffer
, NULL
);
221 _mesa_reference_texobj(&att
->Texture
, NULL
);
223 ASSERT(!att
->Renderbuffer
);
224 ASSERT(!att
->Texture
);
228 /* unbind _Depth/_StencilBuffer to decr ref counts */
229 _mesa_reference_renderbuffer(&fb
->_DepthBuffer
, NULL
);
230 _mesa_reference_renderbuffer(&fb
->_StencilBuffer
, NULL
);
235 * Set *ptr to point to fb, with refcounting and locking.
238 _mesa_reference_framebuffer(struct gl_framebuffer
**ptr
,
239 struct gl_framebuffer
*fb
)
248 /* unreference old renderbuffer */
249 GLboolean deleteFlag
= GL_FALSE
;
250 struct gl_framebuffer
*oldFb
= *ptr
;
252 _glthread_LOCK_MUTEX(oldFb
->Mutex
);
253 ASSERT(oldFb
->RefCount
> 0);
255 deleteFlag
= (oldFb
->RefCount
== 0);
256 _glthread_UNLOCK_MUTEX(oldFb
->Mutex
);
259 oldFb
->Delete(oldFb
);
266 _glthread_LOCK_MUTEX(fb
->Mutex
);
268 _glthread_UNLOCK_MUTEX(fb
->Mutex
);
275 * Resize the given framebuffer's renderbuffers to the new width and height.
276 * This should only be used for window-system framebuffers, not
277 * user-created renderbuffers (i.e. made with GL_EXT_framebuffer_object).
278 * This will typically be called via ctx->Driver.ResizeBuffers() or directly
279 * from a device driver.
281 * \note it's possible for ctx to be null since a window can be resized
282 * without a currently bound rendering context.
285 _mesa_resize_framebuffer(GLcontext
*ctx
, struct gl_framebuffer
*fb
,
286 GLuint width
, GLuint height
)
290 /* XXX I think we could check if the size is not changing
294 /* For window system framebuffers, Name is zero */
295 assert(fb
->Name
== 0);
297 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
298 struct gl_renderbuffer_attachment
*att
= &fb
->Attachment
[i
];
299 if (att
->Type
== GL_RENDERBUFFER_EXT
&& att
->Renderbuffer
) {
300 struct gl_renderbuffer
*rb
= att
->Renderbuffer
;
301 /* only resize if size is changing */
302 if (rb
->Width
!= width
|| rb
->Height
!= height
) {
303 if (rb
->AllocStorage(ctx
, rb
, rb
->InternalFormat
, width
, height
)) {
304 ASSERT(rb
->Width
== width
);
305 ASSERT(rb
->Height
== height
);
308 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "Resizing framebuffer");
315 if (fb
->_DepthBuffer
) {
316 struct gl_renderbuffer
*rb
= fb
->_DepthBuffer
;
317 if (rb
->Width
!= width
|| rb
->Height
!= height
) {
318 if (!rb
->AllocStorage(ctx
, rb
, rb
->InternalFormat
, width
, height
)) {
319 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "Resizing framebuffer");
324 if (fb
->_StencilBuffer
) {
325 struct gl_renderbuffer
*rb
= fb
->_StencilBuffer
;
326 if (rb
->Width
!= width
|| rb
->Height
!= height
) {
327 if (!rb
->AllocStorage(ctx
, rb
, rb
->InternalFormat
, width
, height
)) {
328 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "Resizing framebuffer");
337 /* update scissor / window bounds */
338 _mesa_update_draw_buffer_bounds(ctx
);
339 /* Signal new buffer state so that swrast will update its clipping
340 * info (the CLIP_BIT flag).
342 ctx
->NewState
|= _NEW_BUFFERS
;
349 * XXX THIS IS OBSOLETE - drivers should take care of detecting window
350 * size changes and act accordingly, likely calling _mesa_resize_framebuffer().
352 * GL_MESA_resize_buffers extension.
354 * When this function is called, we'll ask the window system how large
355 * the current window is. If it's a new size, we'll call the driver's
356 * ResizeBuffers function. The driver will then resize its color buffers
357 * as needed, and maybe call the swrast's routine for reallocating
358 * swrast-managed depth/stencil/accum/etc buffers.
359 * \note This function should only be called through the GL API, not
360 * from device drivers (as was done in the past).
363 _mesa_resizebuffers( GLcontext
*ctx
)
365 ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH( ctx
);
367 if (MESA_VERBOSE
& VERBOSE_API
)
368 _mesa_debug(ctx
, "glResizeBuffersMESA\n");
370 if (!ctx
->Driver
.GetBufferSize
) {
374 if (ctx
->WinSysDrawBuffer
) {
375 GLuint newWidth
, newHeight
;
376 GLframebuffer
*buffer
= ctx
->WinSysDrawBuffer
;
378 assert(buffer
->Name
== 0);
380 /* ask device driver for size of output buffer */
381 ctx
->Driver
.GetBufferSize( buffer
, &newWidth
, &newHeight
);
383 /* see if size of device driver's color buffer (window) has changed */
384 if (buffer
->Width
!= newWidth
|| buffer
->Height
!= newHeight
) {
385 if (ctx
->Driver
.ResizeBuffers
)
386 ctx
->Driver
.ResizeBuffers(ctx
, buffer
, newWidth
, newHeight
);
390 if (ctx
->WinSysReadBuffer
391 && ctx
->WinSysReadBuffer
!= ctx
->WinSysDrawBuffer
) {
392 GLuint newWidth
, newHeight
;
393 GLframebuffer
*buffer
= ctx
->WinSysReadBuffer
;
395 assert(buffer
->Name
== 0);
397 /* ask device driver for size of read buffer */
398 ctx
->Driver
.GetBufferSize( buffer
, &newWidth
, &newHeight
);
400 /* see if size of device driver's color buffer (window) has changed */
401 if (buffer
->Width
!= newWidth
|| buffer
->Height
!= newHeight
) {
402 if (ctx
->Driver
.ResizeBuffers
)
403 ctx
->Driver
.ResizeBuffers(ctx
, buffer
, newWidth
, newHeight
);
407 ctx
->NewState
|= _NEW_BUFFERS
; /* to update scissor / window bounds */
412 * XXX THIS IS OBSOLETE
415 _mesa_ResizeBuffersMESA( void )
417 GET_CURRENT_CONTEXT(ctx
);
419 if (ctx
->Extensions
.MESA_resize_buffers
)
420 _mesa_resizebuffers( ctx
);
426 * Examine all the framebuffer's renderbuffers to update the Width/Height
427 * fields of the framebuffer. If we have renderbuffers with different
428 * sizes, set the framebuffer's width and height to the min size.
429 * Note: this is only intended for user-created framebuffers, not
430 * window-system framebuffes.
433 update_framebuffer_size(GLcontext
*ctx
, struct gl_framebuffer
*fb
)
435 GLuint minWidth
= ~0, minHeight
= ~0;
438 /* user-created framebuffers only */
441 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
442 struct gl_renderbuffer_attachment
*att
= &fb
->Attachment
[i
];
443 const struct gl_renderbuffer
*rb
= att
->Renderbuffer
;
445 minWidth
= MIN2(minWidth
, rb
->Width
);
446 minHeight
= MIN2(minHeight
, rb
->Height
);
450 if (minWidth
!= ~0) {
451 fb
->Width
= minWidth
;
452 fb
->Height
= minHeight
;
462 * Update the context's current drawing buffer's Xmin, Xmax, Ymin, Ymax fields.
463 * These values are computed from the buffer's width and height and
464 * the scissor box, if it's enabled.
465 * \param ctx the GL context.
468 _mesa_update_draw_buffer_bounds(GLcontext
*ctx
)
470 struct gl_framebuffer
*buffer
= ctx
->DrawBuffer
;
476 /* user-created framebuffer size depends on the renderbuffers */
477 update_framebuffer_size(ctx
, buffer
);
482 buffer
->_Xmax
= buffer
->Width
;
483 buffer
->_Ymax
= buffer
->Height
;
485 if (ctx
->Scissor
.Enabled
) {
486 if (ctx
->Scissor
.X
> buffer
->_Xmin
) {
487 buffer
->_Xmin
= ctx
->Scissor
.X
;
489 if (ctx
->Scissor
.Y
> buffer
->_Ymin
) {
490 buffer
->_Ymin
= ctx
->Scissor
.Y
;
492 if (ctx
->Scissor
.X
+ ctx
->Scissor
.Width
< buffer
->_Xmax
) {
493 buffer
->_Xmax
= ctx
->Scissor
.X
+ ctx
->Scissor
.Width
;
495 if (ctx
->Scissor
.Y
+ ctx
->Scissor
.Height
< buffer
->_Ymax
) {
496 buffer
->_Ymax
= ctx
->Scissor
.Y
+ ctx
->Scissor
.Height
;
498 /* finally, check for empty region */
499 if (buffer
->_Xmin
> buffer
->_Xmax
) {
500 buffer
->_Xmin
= buffer
->_Xmax
;
502 if (buffer
->_Ymin
> buffer
->_Ymax
) {
503 buffer
->_Ymin
= buffer
->_Ymax
;
507 ASSERT(buffer
->_Xmin
<= buffer
->_Xmax
);
508 ASSERT(buffer
->_Ymin
<= buffer
->_Ymax
);
513 * The glGet queries of the framebuffer red/green/blue size, stencil size,
514 * etc. are satisfied by the fields of ctx->DrawBuffer->Visual. These can
515 * change depending on the renderbuffer bindings. This function updates
516 * the given framebuffer's Visual from the current renderbuffer bindings.
518 * This may apply to user-created framebuffers or window system framebuffers.
520 * Also note: ctx->DrawBuffer->Visual.depthBits might not equal
521 * ctx->DrawBuffer->Attachment[BUFFER_DEPTH].Renderbuffer.DepthBits.
522 * The former one is used to convert floating point depth values into
526 _mesa_update_framebuffer_visual(struct gl_framebuffer
*fb
)
530 memset(&fb
->Visual
, 0, sizeof(fb
->Visual
));
531 fb
->Visual
.rgbMode
= GL_TRUE
; /* assume this */
533 #if 0 /* this _might_ be needed */
534 if (fb
->_Status
!= GL_FRAMEBUFFER_COMPLETE_EXT
) {
535 /* leave visual fields zero'd */
540 /* find first RGB renderbuffer */
541 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
542 if (fb
->Attachment
[i
].Renderbuffer
) {
543 const struct gl_renderbuffer
*rb
= fb
->Attachment
[i
].Renderbuffer
;
544 const GLenum baseFormat
= _mesa_get_format_base_format(rb
->Format
);
545 const gl_format fmt
= rb
->Format
;
547 if (baseFormat
== GL_RGBA
|| baseFormat
== GL_RGB
||
548 baseFormat
== GL_ALPHA
) {
549 fb
->Visual
.redBits
= _mesa_get_format_bits(fmt
, GL_RED_BITS
);
550 fb
->Visual
.greenBits
= _mesa_get_format_bits(fmt
, GL_GREEN_BITS
);
551 fb
->Visual
.blueBits
= _mesa_get_format_bits(fmt
, GL_BLUE_BITS
);
552 fb
->Visual
.alphaBits
= _mesa_get_format_bits(fmt
, GL_ALPHA_BITS
);
553 fb
->Visual
.rgbBits
= fb
->Visual
.redBits
554 + fb
->Visual
.greenBits
+ fb
->Visual
.blueBits
;
555 fb
->Visual
.floatMode
= GL_FALSE
;
556 fb
->Visual
.samples
= rb
->NumSamples
;
562 if (fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
) {
563 const struct gl_renderbuffer
*rb
=
564 fb
->Attachment
[BUFFER_DEPTH
].Renderbuffer
;
565 const gl_format fmt
= rb
->Format
;
566 fb
->Visual
.haveDepthBuffer
= GL_TRUE
;
567 fb
->Visual
.depthBits
= _mesa_get_format_bits(fmt
, GL_DEPTH_BITS
);
570 if (fb
->Attachment
[BUFFER_STENCIL
].Renderbuffer
) {
571 const struct gl_renderbuffer
*rb
=
572 fb
->Attachment
[BUFFER_STENCIL
].Renderbuffer
;
573 const gl_format fmt
= rb
->Format
;
574 fb
->Visual
.haveStencilBuffer
= GL_TRUE
;
575 fb
->Visual
.stencilBits
= _mesa_get_format_bits(fmt
, GL_STENCIL_BITS
);
578 if (fb
->Attachment
[BUFFER_ACCUM
].Renderbuffer
) {
579 const struct gl_renderbuffer
*rb
=
580 fb
->Attachment
[BUFFER_ACCUM
].Renderbuffer
;
581 const gl_format fmt
= rb
->Format
;
582 fb
->Visual
.haveAccumBuffer
= GL_TRUE
;
583 fb
->Visual
.accumRedBits
= _mesa_get_format_bits(fmt
, GL_RED_BITS
);
584 fb
->Visual
.accumGreenBits
= _mesa_get_format_bits(fmt
, GL_GREEN_BITS
);
585 fb
->Visual
.accumBlueBits
= _mesa_get_format_bits(fmt
, GL_BLUE_BITS
);
586 fb
->Visual
.accumAlphaBits
= _mesa_get_format_bits(fmt
, GL_ALPHA_BITS
);
589 compute_depth_max(fb
);
594 * Update the framebuffer's _DepthBuffer field using the renderbuffer
595 * found at the given attachment index.
597 * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
598 * create and install a depth wrapper/adaptor.
600 * \param fb the framebuffer whose _DepthBuffer field to update
601 * \param attIndex indicates the renderbuffer to possibly wrap
604 _mesa_update_depth_buffer(GLcontext
*ctx
,
605 struct gl_framebuffer
*fb
,
608 struct gl_renderbuffer
*depthRb
;
610 /* only one possiblity for now */
611 ASSERT(attIndex
== BUFFER_DEPTH
);
613 depthRb
= fb
->Attachment
[attIndex
].Renderbuffer
;
615 if (depthRb
&& depthRb
->_BaseFormat
== GL_DEPTH_STENCIL
) {
616 /* The attached depth buffer is a GL_DEPTH_STENCIL renderbuffer */
617 if (!fb
->_DepthBuffer
618 || fb
->_DepthBuffer
->Wrapped
!= depthRb
619 || _mesa_get_format_base_format(fb
->_DepthBuffer
->Format
) != GL_DEPTH_COMPONENT
) {
620 /* need to update wrapper */
621 struct gl_renderbuffer
*wrapper
622 = _mesa_new_z24_renderbuffer_wrapper(ctx
, depthRb
);
623 _mesa_reference_renderbuffer(&fb
->_DepthBuffer
, wrapper
);
624 ASSERT(fb
->_DepthBuffer
->Wrapped
== depthRb
);
628 /* depthRb may be null */
629 _mesa_reference_renderbuffer(&fb
->_DepthBuffer
, depthRb
);
635 * Update the framebuffer's _StencilBuffer field using the renderbuffer
636 * found at the given attachment index.
638 * If that attachment points to a combined GL_DEPTH_STENCIL renderbuffer,
639 * create and install a stencil wrapper/adaptor.
641 * \param fb the framebuffer whose _StencilBuffer field to update
642 * \param attIndex indicates the renderbuffer to possibly wrap
645 _mesa_update_stencil_buffer(GLcontext
*ctx
,
646 struct gl_framebuffer
*fb
,
649 struct gl_renderbuffer
*stencilRb
;
651 ASSERT(attIndex
== BUFFER_DEPTH
||
652 attIndex
== BUFFER_STENCIL
);
654 stencilRb
= fb
->Attachment
[attIndex
].Renderbuffer
;
656 if (stencilRb
&& stencilRb
->_BaseFormat
== GL_DEPTH_STENCIL
) {
657 /* The attached stencil buffer is a GL_DEPTH_STENCIL renderbuffer */
658 if (!fb
->_StencilBuffer
659 || fb
->_StencilBuffer
->Wrapped
!= stencilRb
660 || _mesa_get_format_base_format(fb
->_StencilBuffer
->Format
) != GL_STENCIL_INDEX
) {
661 /* need to update wrapper */
662 struct gl_renderbuffer
*wrapper
663 = _mesa_new_s8_renderbuffer_wrapper(ctx
, stencilRb
);
664 _mesa_reference_renderbuffer(&fb
->_StencilBuffer
, wrapper
);
665 ASSERT(fb
->_StencilBuffer
->Wrapped
== stencilRb
);
669 /* stencilRb may be null */
670 _mesa_reference_renderbuffer(&fb
->_StencilBuffer
, stencilRb
);
676 * Example DrawBuffers scenarios:
678 * 1. glDrawBuffer(GL_FRONT_AND_BACK), fixed-func or shader writes to
679 * "gl_FragColor" or program writes to the "result.color" register:
681 * fragment color output renderbuffer
682 * --------------------- ---------------
683 * color[0] Front, Back
686 * 2. glDrawBuffers(3, [GL_FRONT, GL_AUX0, GL_AUX1]), shader writes to
687 * gl_FragData[i] or program writes to result.color[i] registers:
689 * fragment color output renderbuffer
690 * --------------------- ---------------
696 * 3. glDrawBuffers(3, [GL_FRONT, GL_AUX0, GL_AUX1]) and shader writes to
697 * gl_FragColor, or fixed function:
699 * fragment color output renderbuffer
700 * --------------------- ---------------
701 * color[0] Front, Aux0, Aux1
704 * In either case, the list of renderbuffers is stored in the
705 * framebuffer->_ColorDrawBuffers[] array and
706 * framebuffer->_NumColorDrawBuffers indicates the number of buffers.
707 * The renderer (like swrast) has to look at the current fragment shader
708 * to see if it writes to gl_FragColor vs. gl_FragData[i] to determine
709 * how to map color outputs to renderbuffers.
711 * Note that these two calls are equivalent (for fixed function fragment
713 * a) glDrawBuffer(GL_FRONT_AND_BACK); (assuming non-stereo framebuffer)
714 * b) glDrawBuffers(2, [GL_FRONT_LEFT, GL_BACK_LEFT]);
721 * Update the (derived) list of color drawing renderbuffer pointers.
722 * Later, when we're rendering we'll loop from 0 to _NumColorDrawBuffers
726 update_color_draw_buffers(GLcontext
*ctx
, struct gl_framebuffer
*fb
)
730 /* set 0th buffer to NULL now in case _NumColorDrawBuffers is zero */
731 fb
->_ColorDrawBuffers
[0] = NULL
;
733 for (output
= 0; output
< fb
->_NumColorDrawBuffers
; output
++) {
734 GLint buf
= fb
->_ColorDrawBufferIndexes
[output
];
736 fb
->_ColorDrawBuffers
[output
] = fb
->Attachment
[buf
].Renderbuffer
;
739 fb
->_ColorDrawBuffers
[output
] = NULL
;
746 * Update the (derived) color read renderbuffer pointer.
747 * Unlike the DrawBuffer, we can only read from one (or zero) color buffers.
750 update_color_read_buffer(GLcontext
*ctx
, struct gl_framebuffer
*fb
)
753 if (fb
->_ColorReadBufferIndex
== -1 ||
757 fb
->_ColorReadBuffer
= NULL
; /* legal! */
760 ASSERT(fb
->_ColorReadBufferIndex
>= 0);
761 ASSERT(fb
->_ColorReadBufferIndex
< BUFFER_COUNT
);
763 = fb
->Attachment
[fb
->_ColorReadBufferIndex
].Renderbuffer
;
769 * Update a gl_framebuffer's derived state.
771 * Specifically, update these framebuffer fields:
773 * _NumColorDrawBuffers
778 * If the framebuffer is user-created, make sure it's complete.
780 * The following functions (at least) can effect framebuffer state:
781 * glReadBuffer, glDrawBuffer, glDrawBuffersARB, glFramebufferRenderbufferEXT,
782 * glRenderbufferStorageEXT.
785 update_framebuffer(GLcontext
*ctx
, struct gl_framebuffer
*fb
)
788 /* This is a window-system framebuffer */
789 /* Need to update the FB's GL_DRAW_BUFFER state to match the
790 * context state (GL_READ_BUFFER too).
792 if (fb
->ColorDrawBuffer
[0] != ctx
->Color
.DrawBuffer
[0]) {
793 _mesa_drawbuffers(ctx
, ctx
->Const
.MaxDrawBuffers
,
794 ctx
->Color
.DrawBuffer
, NULL
);
796 if (fb
->ColorReadBuffer
!= ctx
->Pixel
.ReadBuffer
) {
801 /* This is a user-created framebuffer.
802 * Completeness only matters for user-created framebuffers.
804 if (fb
->_Status
!= GL_FRAMEBUFFER_COMPLETE
) {
805 _mesa_test_framebuffer_completeness(ctx
, fb
);
809 /* Strictly speaking, we don't need to update the draw-state
810 * if this FB is bound as ctx->ReadBuffer (and conversely, the
811 * read-state if this FB is bound as ctx->DrawBuffer), but no
814 update_color_draw_buffers(ctx
, fb
);
815 update_color_read_buffer(ctx
, fb
);
816 _mesa_update_depth_buffer(ctx
, fb
, BUFFER_DEPTH
);
817 _mesa_update_stencil_buffer(ctx
, fb
, BUFFER_STENCIL
);
819 compute_depth_max(fb
);
824 * Update state related to the current draw/read framebuffers.
827 _mesa_update_framebuffer(GLcontext
*ctx
)
829 struct gl_framebuffer
*drawFb
;
830 struct gl_framebuffer
*readFb
;
833 drawFb
= ctx
->DrawBuffer
;
834 readFb
= ctx
->ReadBuffer
;
836 update_framebuffer(ctx
, drawFb
);
837 if (readFb
!= drawFb
)
838 update_framebuffer(ctx
, readFb
);
843 * Check if the renderbuffer for a read operation (glReadPixels, glCopyPixels,
844 * glCopyTex[Sub]Image, etc) exists.
845 * \param format a basic image format such as GL_RGB, GL_RGBA, GL_ALPHA,
846 * GL_DEPTH_COMPONENT, etc. or GL_COLOR, GL_DEPTH, GL_STENCIL.
847 * \return GL_TRUE if buffer exists, GL_FALSE otherwise
850 _mesa_source_buffer_exists(GLcontext
*ctx
, GLenum format
)
852 const struct gl_renderbuffer_attachment
*att
= ctx
->ReadBuffer
->Attachment
;
854 /* If we don't know the framebuffer status, update it now */
855 if (ctx
->ReadBuffer
->_Status
== 0) {
856 _mesa_test_framebuffer_completeness(ctx
, ctx
->ReadBuffer
);
859 if (ctx
->ReadBuffer
->_Status
!= GL_FRAMEBUFFER_COMPLETE_EXT
) {
870 case GL_LUMINANCE_ALPHA
:
878 if (ctx
->ReadBuffer
->_ColorReadBuffer
== NULL
) {
881 ASSERT(_mesa_get_format_bits(ctx
->ReadBuffer
->_ColorReadBuffer
->Format
, GL_RED_BITS
) > 0 ||
882 _mesa_get_format_bits(ctx
->ReadBuffer
->_ColorReadBuffer
->Format
, GL_ALPHA_BITS
) > 0 ||
883 _mesa_get_format_bits(ctx
->ReadBuffer
->_ColorReadBuffer
->Format
, GL_INDEX_BITS
) > 0);
886 case GL_DEPTH_COMPONENT
:
887 if (!att
[BUFFER_DEPTH
].Renderbuffer
) {
890 /*ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);*/
893 case GL_STENCIL_INDEX
:
894 if (!att
[BUFFER_STENCIL
].Renderbuffer
) {
897 /*ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);*/
899 case GL_DEPTH_STENCIL_EXT
:
900 if (!att
[BUFFER_DEPTH
].Renderbuffer
||
901 !att
[BUFFER_STENCIL
].Renderbuffer
) {
905 ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);
906 ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);
911 "Unexpected format 0x%x in _mesa_source_buffer_exists",
922 * As above, but for drawing operations.
923 * XXX could do some code merging w/ above function.
926 _mesa_dest_buffer_exists(GLcontext
*ctx
, GLenum format
)
928 const struct gl_renderbuffer_attachment
*att
= ctx
->DrawBuffer
->Attachment
;
930 /* If we don't know the framebuffer status, update it now */
931 if (ctx
->DrawBuffer
->_Status
== 0) {
932 _mesa_test_framebuffer_completeness(ctx
, ctx
->DrawBuffer
);
935 if (ctx
->DrawBuffer
->_Status
!= GL_FRAMEBUFFER_COMPLETE_EXT
) {
946 case GL_LUMINANCE_ALPHA
:
954 /* Nothing special since GL_DRAW_BUFFER could be GL_NONE. */
955 /* Could assert that colorbuffer has RedBits > 0 */
958 case GL_DEPTH_COMPONENT
:
959 if (!att
[BUFFER_DEPTH
].Renderbuffer
) {
962 /*ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);*/
965 case GL_STENCIL_INDEX
:
966 if (!att
[BUFFER_STENCIL
].Renderbuffer
) {
969 /*ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);*/
971 case GL_DEPTH_STENCIL_EXT
:
972 if (!att
[BUFFER_DEPTH
].Renderbuffer
||
973 !att
[BUFFER_STENCIL
].Renderbuffer
) {
977 ASSERT(att[BUFFER_DEPTH].Renderbuffer->DepthBits > 0);
978 ASSERT(att[BUFFER_STENCIL].Renderbuffer->StencilBits > 0);
983 "Unexpected format 0x%x in _mesa_dest_buffer_exists",
994 * Used to answer the GL_IMPLEMENTATION_COLOR_READ_FORMAT_OES query.
997 _mesa_get_color_read_format(GLcontext
*ctx
)
999 switch (ctx
->ReadBuffer
->_ColorReadBuffer
->Format
) {
1000 case MESA_FORMAT_ARGB8888
:
1002 case MESA_FORMAT_RGB565
:
1011 * Used to answer the GL_IMPLEMENTATION_COLOR_READ_TYPE_OES query.
1014 _mesa_get_color_read_type(GLcontext
*ctx
)
1016 switch (ctx
->ReadBuffer
->_ColorReadBuffer
->Format
) {
1017 case MESA_FORMAT_ARGB8888
:
1018 return GL_UNSIGNED_BYTE
;
1019 case MESA_FORMAT_RGB565
:
1020 return GL_UNSIGNED_SHORT_5_6_5_REV
;
1022 return GL_UNSIGNED_BYTE
;
1028 * Print framebuffer info to stderr, for debugging.
1031 _mesa_print_framebuffer(const struct gl_framebuffer
*fb
)
1035 fprintf(stderr
, "Mesa Framebuffer %u at %p\n", fb
->Name
, (void *) fb
);
1036 fprintf(stderr
, " Size: %u x %u Status: %s\n", fb
->Width
, fb
->Height
,
1037 _mesa_lookup_enum_by_nr(fb
->_Status
));
1038 fprintf(stderr
, " Attachments:\n");
1040 for (i
= 0; i
< BUFFER_COUNT
; i
++) {
1041 const struct gl_renderbuffer_attachment
*att
= &fb
->Attachment
[i
];
1042 if (att
->Type
== GL_TEXTURE
) {
1043 const struct gl_texture_image
*texImage
;
1045 " %2d: Texture %u, level %u, face %u, slice %u, complete %d\n",
1046 i
, att
->Texture
->Name
, att
->TextureLevel
, att
->CubeMapFace
,
1047 att
->Zoffset
, att
->Complete
);
1048 texImage
= att
->Texture
->Image
[att
->CubeMapFace
][att
->TextureLevel
];
1049 fprintf(stderr
, " Size: %u x %u x %u Format %s\n",
1050 texImage
->Width
, texImage
->Height
, texImage
->Depth
,
1051 _mesa_get_format_name(texImage
->TexFormat
));
1053 else if (att
->Type
== GL_RENDERBUFFER
) {
1054 fprintf(stderr
, " %2d: Renderbuffer %u, complete %d\n",
1055 i
, att
->Renderbuffer
->Name
, att
->Complete
);
1056 fprintf(stderr
, " Size: %u x %u Format %s\n",
1057 att
->Renderbuffer
->Width
, att
->Renderbuffer
->Height
,
1058 _mesa_get_format_name(att
->Renderbuffer
->Format
));
1061 fprintf(stderr
, " %2d: none\n", i
);