2 * Mesa 3-D graphics library
4 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
28 * glReadBuffer, DrawBuffer functions.
39 #include "util/bitscan.h"
40 #include "util/u_math.h"
47 * Return bitmask of BUFFER_BIT_* flags indicating which color buffers are
48 * available to the rendering context (for drawing or reading).
49 * This depends on the type of framebuffer. For window system framebuffers
50 * we look at the framebuffer's visual. But for user-create framebuffers we
51 * look at the number of supported color attachments.
52 * \param fb the framebuffer to draw to, or read from
53 * \return bitmask of BUFFER_BIT_* flags
56 supported_buffer_bitmask(const struct gl_context
*ctx
,
57 const struct gl_framebuffer
*fb
)
59 GLbitfield mask
= 0x0;
61 if (_mesa_is_user_fbo(fb
)) {
62 /* A user-created renderbuffer */
63 mask
= ((1 << ctx
->Const
.MaxColorAttachments
) - 1) << BUFFER_COLOR0
;
66 /* A window system framebuffer */
68 mask
= BUFFER_BIT_FRONT_LEFT
; /* always have this */
69 if (fb
->Visual
.stereoMode
) {
70 mask
|= BUFFER_BIT_FRONT_RIGHT
;
71 if (fb
->Visual
.doubleBufferMode
) {
72 mask
|= BUFFER_BIT_BACK_LEFT
| BUFFER_BIT_BACK_RIGHT
;
75 else if (fb
->Visual
.doubleBufferMode
) {
76 mask
|= BUFFER_BIT_BACK_LEFT
;
79 for (i
= 0; i
< fb
->Visual
.numAuxBuffers
; i
++) {
80 mask
|= (BUFFER_BIT_AUX0
<< i
);
88 back_to_front_if_single_buffered(const struct gl_context
*ctx
, GLenum buffer
)
90 /* If the front buffer is the only buffer, GL_BACK and all other flags
91 * that include BACK select the front buffer for drawing. There are
92 * several reasons we want to do this.
94 * 1) OpenGL ES 3.0 requires it:
96 * Page 181 (page 192 of the PDF) in section 4.2.1 of the OpenGL
97 * ES 3.0.1 specification says:
99 * "When draw buffer zero is BACK, color values are written
100 * into the sole buffer for single-buffered contexts, or into
101 * the back buffer for double-buffered contexts."
103 * We also do this for GLES 1 and 2 because those APIs have no
104 * concept of selecting the front and back buffer anyway and it's
105 * convenient to be able to maintain the magic behaviour of
106 * GL_BACK in that case.
108 * 2) Pbuffers are back buffers from the application point of view,
109 * but they are front buffers from the Mesa point of view,
110 * because they are always single buffered.
112 if (!ctx
->DrawBuffer
->Visual
.doubleBufferMode
) {
118 buffer
= GL_FRONT_RIGHT
;
121 buffer
= GL_FRONT_LEFT
;
130 * Helper routine used by glDrawBuffer and glDrawBuffersARB.
131 * Given a GLenum naming one or more color buffers (such as
132 * GL_FRONT_AND_BACK), return the corresponding bitmask of BUFFER_BIT_* flags.
135 draw_buffer_enum_to_bitmask(const struct gl_context
*ctx
, GLenum buffer
)
137 buffer
= back_to_front_if_single_buffered(ctx
, buffer
);
143 return BUFFER_BIT_FRONT_LEFT
| BUFFER_BIT_FRONT_RIGHT
;
145 return BUFFER_BIT_BACK_LEFT
| BUFFER_BIT_BACK_RIGHT
;
147 return BUFFER_BIT_FRONT_RIGHT
| BUFFER_BIT_BACK_RIGHT
;
149 return BUFFER_BIT_FRONT_RIGHT
;
151 return BUFFER_BIT_BACK_RIGHT
;
153 return BUFFER_BIT_BACK_LEFT
;
154 case GL_FRONT_AND_BACK
:
155 return BUFFER_BIT_FRONT_LEFT
| BUFFER_BIT_BACK_LEFT
156 | BUFFER_BIT_FRONT_RIGHT
| BUFFER_BIT_BACK_RIGHT
;
158 return BUFFER_BIT_FRONT_LEFT
| BUFFER_BIT_BACK_LEFT
;
160 return BUFFER_BIT_FRONT_LEFT
;
162 return BUFFER_BIT_AUX0
;
166 return 1 << BUFFER_COUNT
; /* invalid, but not BAD_MASK */
167 case GL_COLOR_ATTACHMENT0_EXT
:
168 return BUFFER_BIT_COLOR0
;
169 case GL_COLOR_ATTACHMENT1_EXT
:
170 return BUFFER_BIT_COLOR1
;
171 case GL_COLOR_ATTACHMENT2_EXT
:
172 return BUFFER_BIT_COLOR2
;
173 case GL_COLOR_ATTACHMENT3_EXT
:
174 return BUFFER_BIT_COLOR3
;
175 case GL_COLOR_ATTACHMENT4_EXT
:
176 return BUFFER_BIT_COLOR4
;
177 case GL_COLOR_ATTACHMENT5_EXT
:
178 return BUFFER_BIT_COLOR5
;
179 case GL_COLOR_ATTACHMENT6_EXT
:
180 return BUFFER_BIT_COLOR6
;
181 case GL_COLOR_ATTACHMENT7_EXT
:
182 return BUFFER_BIT_COLOR7
;
184 /* not an error, but also not supported */
185 if (buffer
>= GL_COLOR_ATTACHMENT8
&& buffer
<= GL_COLOR_ATTACHMENT31
)
186 return 1 << BUFFER_COUNT
;
194 * Helper routine used by glReadBuffer.
195 * Given a GLenum naming a color buffer, return the index of the corresponding
196 * renderbuffer (a BUFFER_* value).
197 * return BUFFER_NONE for an invalid buffer.
199 static gl_buffer_index
200 read_buffer_enum_to_index(const struct gl_context
*ctx
, GLenum buffer
)
202 buffer
= back_to_front_if_single_buffered(ctx
, buffer
);
206 return BUFFER_FRONT_LEFT
;
208 return BUFFER_BACK_LEFT
;
210 return BUFFER_FRONT_RIGHT
;
212 return BUFFER_FRONT_RIGHT
;
214 return BUFFER_BACK_RIGHT
;
216 return BUFFER_BACK_LEFT
;
218 return BUFFER_FRONT_LEFT
;
220 return BUFFER_FRONT_LEFT
;
223 case GL_FRONT_AND_BACK
:
224 return BUFFER_FRONT_LEFT
;
228 return BUFFER_COUNT
; /* invalid, but not -1 */
229 case GL_COLOR_ATTACHMENT0_EXT
:
230 return BUFFER_COLOR0
;
231 case GL_COLOR_ATTACHMENT1_EXT
:
232 return BUFFER_COLOR1
;
233 case GL_COLOR_ATTACHMENT2_EXT
:
234 return BUFFER_COLOR2
;
235 case GL_COLOR_ATTACHMENT3_EXT
:
236 return BUFFER_COLOR3
;
237 case GL_COLOR_ATTACHMENT4_EXT
:
238 return BUFFER_COLOR4
;
239 case GL_COLOR_ATTACHMENT5_EXT
:
240 return BUFFER_COLOR5
;
241 case GL_COLOR_ATTACHMENT6_EXT
:
242 return BUFFER_COLOR6
;
243 case GL_COLOR_ATTACHMENT7_EXT
:
244 return BUFFER_COLOR7
;
246 /* not an error, but also not supported */
247 if (buffer
>= GL_COLOR_ATTACHMENT8
&& buffer
<= GL_COLOR_ATTACHMENT31
)
255 is_legal_es3_readbuffer_enum(GLenum buf
)
257 return buf
== GL_BACK
|| buf
== GL_NONE
||
258 (buf
>= GL_COLOR_ATTACHMENT0
&& buf
<= GL_COLOR_ATTACHMENT31
);
262 * Called by glDrawBuffer() and glNamedFramebufferDrawBuffer().
263 * Specify which renderbuffer(s) to draw into for the first color output.
264 * <buffer> can name zero, one, two or four renderbuffers!
265 * \sa _mesa_DrawBuffers
267 * \param buffer buffer token such as GL_LEFT or GL_FRONT_AND_BACK, etc.
269 * Note that the behaviour of this function depends on whether the
270 * current ctx->DrawBuffer is a window-system framebuffer or a user-created
271 * framebuffer object.
272 * In the former case, we update the per-context ctx->Color.DrawBuffer
273 * state var _and_ the FB's ColorDrawBuffer state.
274 * In the later case, we update the FB's ColorDrawBuffer state only.
276 * Furthermore, upon a MakeCurrent() or BindFramebuffer() call, if the
277 * new FB is a window system FB, we need to re-update the FB's
278 * ColorDrawBuffer state to match the context. This is handled in
279 * _mesa_update_framebuffer().
281 * See the GL_EXT_framebuffer_object spec for more info.
283 static ALWAYS_INLINE
void
284 draw_buffer(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
285 GLenum buffer
, const char *caller
, bool no_error
)
289 FLUSH_VERTICES(ctx
, 0);
291 if (MESA_VERBOSE
& VERBOSE_API
) {
292 _mesa_debug(ctx
, "%s %s\n", caller
, _mesa_enum_to_string(buffer
));
295 if (buffer
== GL_NONE
) {
299 const GLbitfield supportedMask
300 = supported_buffer_bitmask(ctx
, fb
);
301 destMask
= draw_buffer_enum_to_bitmask(ctx
, buffer
);
302 if (!no_error
&& destMask
== BAD_MASK
) {
303 /* totally bogus buffer */
304 _mesa_error(ctx
, GL_INVALID_ENUM
, "%s(invalid buffer %s)", caller
,
305 _mesa_enum_to_string(buffer
));
308 destMask
&= supportedMask
;
309 if (!no_error
&& destMask
== 0x0) {
310 /* none of the named color buffers exist! */
311 _mesa_error(ctx
, GL_INVALID_OPERATION
, "%s(invalid buffer %s)",
312 caller
, _mesa_enum_to_string(buffer
));
317 /* if we get here, there's no error so set new state */
318 const GLenum16 buffer16
= buffer
;
319 _mesa_drawbuffers(ctx
, fb
, 1, &buffer16
, &destMask
);
321 /* Call device driver function only if fb is the bound draw buffer */
322 if (fb
== ctx
->DrawBuffer
) {
323 if (ctx
->Driver
.DrawBuffer
)
324 ctx
->Driver
.DrawBuffer(ctx
);
325 if (ctx
->Driver
.DrawBufferAllocate
)
326 ctx
->Driver
.DrawBufferAllocate(ctx
);
332 draw_buffer_error(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
333 GLenum buffer
, const char *caller
)
335 draw_buffer(ctx
, fb
, buffer
, caller
, false);
340 draw_buffer_no_error(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
341 GLenum buffer
, const char *caller
)
343 draw_buffer(ctx
, fb
, buffer
, caller
, true);
348 _mesa_DrawBuffer_no_error(GLenum buffer
)
350 GET_CURRENT_CONTEXT(ctx
);
351 draw_buffer_no_error(ctx
, ctx
->DrawBuffer
, buffer
, "glDrawBuffer");
356 _mesa_DrawBuffer(GLenum buffer
)
358 GET_CURRENT_CONTEXT(ctx
);
359 draw_buffer_error(ctx
, ctx
->DrawBuffer
, buffer
, "glDrawBuffer");
364 _mesa_NamedFramebufferDrawBuffer_no_error(GLuint framebuffer
, GLenum buf
)
366 GET_CURRENT_CONTEXT(ctx
);
367 struct gl_framebuffer
*fb
;
370 fb
= _mesa_lookup_framebuffer(ctx
, framebuffer
);
372 fb
= ctx
->WinSysDrawBuffer
;
375 draw_buffer_no_error(ctx
, fb
, buf
, "glNamedFramebufferDrawBuffer");
380 _mesa_NamedFramebufferDrawBuffer(GLuint framebuffer
, GLenum buf
)
382 GET_CURRENT_CONTEXT(ctx
);
383 struct gl_framebuffer
*fb
;
386 fb
= _mesa_lookup_framebuffer_err(ctx
, framebuffer
,
387 "glNamedFramebufferDrawBuffer");
392 fb
= ctx
->WinSysDrawBuffer
;
394 draw_buffer_error(ctx
, fb
, buf
, "glNamedFramebufferDrawBuffer");
399 * Called by glDrawBuffersARB() and glNamedFramebufferDrawBuffers() to specify
400 * the destination color renderbuffers for N fragment program color outputs.
401 * \sa _mesa_DrawBuffer
402 * \param n number of outputs
403 * \param buffers array [n] of renderbuffer names. Unlike glDrawBuffer, the
404 * names cannot specify more than one buffer. For example,
405 * GL_FRONT_AND_BACK is illegal. The only exception is GL_BACK
406 * that is considered special and allowed as far as n is one
409 static ALWAYS_INLINE
void
410 draw_buffers(struct gl_context
*ctx
, struct gl_framebuffer
*fb
, GLsizei n
,
411 const GLenum
*buffers
, const char *caller
, bool no_error
)
414 GLbitfield usedBufferMask
, supportedMask
;
415 GLbitfield destMask
[MAX_DRAW_BUFFERS
];
417 FLUSH_VERTICES(ctx
, 0);
420 /* Turns out n==0 is a valid input that should not produce an error.
421 * The remaining code below correctly handles the n==0 case.
423 * From the OpenGL 3.0 specification, page 258:
424 * "An INVALID_VALUE error is generated if n is greater than
428 _mesa_error(ctx
, GL_INVALID_VALUE
, "%s(n < 0)", caller
);
432 if (n
> (GLsizei
) ctx
->Const
.MaxDrawBuffers
) {
433 _mesa_error(ctx
, GL_INVALID_VALUE
,
434 "%s(n > maximum number of draw buffers)", caller
);
438 /* From the ES 3.0 specification, page 180:
439 * "If the GL is bound to the default framebuffer, then n must be 1
440 * and the constant must be BACK or NONE."
441 * (same restriction applies with GL_EXT_draw_buffers specification)
443 if (ctx
->API
== API_OPENGLES2
&& _mesa_is_winsys_fbo(fb
) &&
444 (n
!= 1 || (buffers
[0] != GL_NONE
&& buffers
[0] != GL_BACK
))) {
445 _mesa_error(ctx
, GL_INVALID_OPERATION
, "%s(invalid buffers)", caller
);
450 supportedMask
= supported_buffer_bitmask(ctx
, fb
);
451 usedBufferMask
= 0x0;
453 /* complicated error checking... */
454 for (output
= 0; output
< n
; output
++) {
456 /* From the OpenGL 4.5 specification, page 493 (page 515 of the PDF)
457 * "An INVALID_ENUM error is generated if any value in bufs is FRONT,
458 * LEFT, RIGHT, or FRONT_AND_BACK . This restriction applies to both
459 * the default framebuffer and framebuffer objects, and exists because
460 * these constants may themselves refer to multiple buffers, as shown
463 * From the OpenGL 4.5 specification, page 492 (page 514 of the PDF):
464 * "If the default framebuffer is affected, then each of the constants
465 * must be one of the values listed in table 17.6 or the special value
466 * BACK. When BACK is used, n must be 1 and color values are written
467 * into the left buffer for single-buffered contexts, or into the back
468 * left buffer for double-buffered contexts."
470 * Note "special value BACK". GL_BACK also refers to multiple buffers,
471 * but it is consider a special case here. This is a change on 4.5.
472 * For OpenGL 4.x we check that behaviour. For any previous version we
473 * keep considering it wrong (as INVALID_ENUM).
475 if (buffers
[output
] == GL_BACK
&&
476 _mesa_is_winsys_fbo(fb
) &&
477 _mesa_is_desktop_gl(ctx
) &&
478 ctx
->Version
>= 40) {
480 _mesa_error(ctx
, GL_INVALID_OPERATION
, "%s(with GL_BACK n must be 1)",
484 } else if (buffers
[output
] == GL_FRONT
||
485 buffers
[output
] == GL_LEFT
||
486 buffers
[output
] == GL_RIGHT
||
487 buffers
[output
] == GL_FRONT_AND_BACK
||
488 (buffers
[output
] == GL_BACK
&&
489 _mesa_is_desktop_gl(ctx
))) {
490 _mesa_error(ctx
, GL_INVALID_ENUM
, "%s(invalid buffer %s)",
491 caller
, _mesa_enum_to_string(buffers
[output
]));
496 destMask
[output
] = draw_buffer_enum_to_bitmask(ctx
, buffers
[output
]);
499 /* From the OpenGL 3.0 specification, page 258:
500 * "Each buffer listed in bufs must be one of the values from tables
501 * 4.5 or 4.6. Otherwise, an INVALID_ENUM error is generated.
503 if (destMask
[output
] == BAD_MASK
) {
504 _mesa_error(ctx
, GL_INVALID_ENUM
, "%s(invalid buffer %s)",
505 caller
, _mesa_enum_to_string(buffers
[output
]));
509 /* Section 4.2 (Whole Framebuffer Operations) of the OpenGL ES 3.0
510 * specification says:
512 * "If the GL is bound to a draw framebuffer object, the ith
513 * buffer listed in bufs must be COLOR_ATTACHMENTi or NONE .
514 * Specifying a buffer out of order, BACK , or COLOR_ATTACHMENTm
515 * where m is greater than or equal to the value of MAX_-
516 * COLOR_ATTACHMENTS , will generate the error INVALID_OPERATION .
518 if (_mesa_is_gles3(ctx
) && _mesa_is_user_fbo(fb
) &&
519 buffers
[output
] != GL_NONE
&&
520 (buffers
[output
] < GL_COLOR_ATTACHMENT0
||
521 buffers
[output
] >= GL_COLOR_ATTACHMENT0
+ ctx
->Const
.MaxColorAttachments
)) {
522 _mesa_error(ctx
, GL_INVALID_OPERATION
, "glDrawBuffers(buffer)");
527 if (buffers
[output
] == GL_NONE
) {
528 destMask
[output
] = 0x0;
531 /* Page 259 (page 275 of the PDF) in section 4.2.1 of the OpenGL 3.0
532 * spec (20080923) says:
534 * "If the GL is bound to a framebuffer object and DrawBuffers is
535 * supplied with [...] COLOR_ATTACHMENTm where m is greater than
536 * or equal to the value of MAX_COLOR_ATTACHMENTS, then the error
537 * INVALID_OPERATION results."
539 if (!no_error
&& _mesa_is_user_fbo(fb
) && buffers
[output
] >=
540 GL_COLOR_ATTACHMENT0
+ ctx
->Const
.MaxDrawBuffers
) {
541 _mesa_error(ctx
, GL_INVALID_OPERATION
,
542 "%s(buffers[%d] >= maximum number of draw buffers)",
547 /* From the OpenGL 3.0 specification, page 259:
548 * "If the GL is bound to the default framebuffer and DrawBuffers is
549 * supplied with a constant (other than NONE) that does not indicate
550 * any of the color buffers allocated to the GL context by the window
551 * system, the error INVALID_OPERATION will be generated.
553 * If the GL is bound to a framebuffer object and DrawBuffers is
554 * supplied with a constant from table 4.6 [...] then the error
555 * INVALID_OPERATION results."
557 destMask
[output
] &= supportedMask
;
559 if (destMask
[output
] == 0) {
560 _mesa_error(ctx
, GL_INVALID_OPERATION
,
561 "%s(unsupported buffer %s)",
562 caller
, _mesa_enum_to_string(buffers
[output
]));
566 /* ES 3.0 is even more restrictive. From the ES 3.0 spec, page 180:
567 * "If the GL is bound to a framebuffer object, the ith buffer
568 * listed in bufs must be COLOR_ATTACHMENTi or NONE. [...]
569 * INVALID_OPERATION." (same restriction applies with
570 * GL_EXT_draw_buffers specification)
572 if (ctx
->API
== API_OPENGLES2
&& _mesa_is_user_fbo(fb
) &&
573 buffers
[output
] != GL_NONE
&&
574 buffers
[output
] != GL_COLOR_ATTACHMENT0
+ output
) {
575 _mesa_error(ctx
, GL_INVALID_OPERATION
,
576 "%s(unsupported buffer %s)",
577 caller
, _mesa_enum_to_string(buffers
[output
]));
581 /* From the OpenGL 3.0 specification, page 258:
582 * "Except for NONE, a buffer may not appear more than once in the
583 * array pointed to by bufs. Specifying a buffer more then once
584 * will result in the error INVALID_OPERATION."
586 if (destMask
[output
] & usedBufferMask
) {
587 _mesa_error(ctx
, GL_INVALID_OPERATION
,
588 "%s(duplicated buffer %s)",
589 caller
, _mesa_enum_to_string(buffers
[output
]));
595 usedBufferMask
|= destMask
[output
];
599 /* OK, if we get here, there were no errors so set the new state */
600 GLenum16 buffers16
[MAX_DRAW_BUFFERS
];
601 for (int i
= 0; i
< n
; i
++)
602 buffers16
[i
] = buffers
[i
];
604 _mesa_drawbuffers(ctx
, fb
, n
, buffers16
, destMask
);
607 * Call device driver function if fb is the bound draw buffer.
608 * Note that n can be equal to 0,
609 * in which case we don't want to reference buffers[0], which
612 if (fb
== ctx
->DrawBuffer
) {
613 if (ctx
->Driver
.DrawBuffer
)
614 ctx
->Driver
.DrawBuffer(ctx
);
615 if (ctx
->Driver
.DrawBufferAllocate
)
616 ctx
->Driver
.DrawBufferAllocate(ctx
);
622 draw_buffers_error(struct gl_context
*ctx
, struct gl_framebuffer
*fb
, GLsizei n
,
623 const GLenum
*buffers
, const char *caller
)
625 draw_buffers(ctx
, fb
, n
, buffers
, caller
, false);
630 draw_buffers_no_error(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
631 GLsizei n
, const GLenum
*buffers
, const char *caller
)
633 draw_buffers(ctx
, fb
, n
, buffers
, caller
, true);
638 _mesa_DrawBuffers_no_error(GLsizei n
, const GLenum
*buffers
)
640 GET_CURRENT_CONTEXT(ctx
);
641 draw_buffers_no_error(ctx
, ctx
->DrawBuffer
, n
, buffers
, "glDrawBuffers");
646 _mesa_DrawBuffers(GLsizei n
, const GLenum
*buffers
)
648 GET_CURRENT_CONTEXT(ctx
);
649 draw_buffers_error(ctx
, ctx
->DrawBuffer
, n
, buffers
, "glDrawBuffers");
654 _mesa_NamedFramebufferDrawBuffers_no_error(GLuint framebuffer
, GLsizei n
,
657 GET_CURRENT_CONTEXT(ctx
);
658 struct gl_framebuffer
*fb
;
661 fb
= _mesa_lookup_framebuffer(ctx
, framebuffer
);
663 fb
= ctx
->WinSysDrawBuffer
;
666 draw_buffers_no_error(ctx
, fb
, n
, bufs
, "glNamedFramebufferDrawBuffers");
671 _mesa_NamedFramebufferDrawBuffers(GLuint framebuffer
, GLsizei n
,
674 GET_CURRENT_CONTEXT(ctx
);
675 struct gl_framebuffer
*fb
;
678 fb
= _mesa_lookup_framebuffer_err(ctx
, framebuffer
,
679 "glNamedFramebufferDrawBuffers");
684 fb
= ctx
->WinSysDrawBuffer
;
686 draw_buffers_error(ctx
, fb
, n
, bufs
, "glNamedFramebufferDrawBuffers");
691 * Performs necessary state updates when _mesa_drawbuffers makes an
695 updated_drawbuffers(struct gl_context
*ctx
, struct gl_framebuffer
*fb
)
697 FLUSH_VERTICES(ctx
, _NEW_BUFFERS
);
699 if (ctx
->API
== API_OPENGL_COMPAT
&& !ctx
->Extensions
.ARB_ES2_compatibility
) {
700 /* Flag the FBO as requiring validation. */
701 if (_mesa_is_user_fbo(fb
)) {
709 * Helper function to set the GL_DRAW_BUFFER state for the given context and
710 * FBO. Called via glDrawBuffer(), glDrawBuffersARB()
712 * All error checking will have been done prior to calling this function
713 * so nothing should go wrong at this point.
715 * \param ctx current context
716 * \param fb the desired draw buffer
717 * \param n number of color outputs to set
718 * \param buffers array[n] of colorbuffer names, like GL_LEFT.
719 * \param destMask array[n] of BUFFER_BIT_* bitmasks which correspond to the
720 * colorbuffer names. (i.e. GL_FRONT_AND_BACK =>
721 * BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT).
724 _mesa_drawbuffers(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
725 GLuint n
, const GLenum16
*buffers
,
726 const GLbitfield
*destMask
)
728 GLbitfield mask
[MAX_DRAW_BUFFERS
];
732 /* compute destMask values now */
733 const GLbitfield supportedMask
= supported_buffer_bitmask(ctx
, fb
);
735 for (output
= 0; output
< n
; output
++) {
736 mask
[output
] = draw_buffer_enum_to_bitmask(ctx
, buffers
[output
]);
737 assert(mask
[output
] != BAD_MASK
);
738 mask
[output
] &= supportedMask
;
744 * destMask[0] may have up to four bits set
745 * (ex: glDrawBuffer(GL_FRONT_AND_BACK)).
746 * Otherwise, destMask[x] can only have one bit set.
748 if (n
> 0 && util_bitcount(destMask
[0]) > 1) {
749 GLuint count
= 0, destMask0
= destMask
[0];
751 const gl_buffer_index bufIndex
= u_bit_scan(&destMask0
);
752 if (fb
->_ColorDrawBufferIndexes
[count
] != bufIndex
) {
753 updated_drawbuffers(ctx
, fb
);
754 fb
->_ColorDrawBufferIndexes
[count
] = bufIndex
;
758 fb
->ColorDrawBuffer
[0] = buffers
[0];
759 fb
->_NumColorDrawBuffers
= count
;
763 for (buf
= 0; buf
< n
; buf
++ ) {
765 gl_buffer_index bufIndex
= ffs(destMask
[buf
]) - 1;
766 /* only one bit should be set in the destMask[buf] field */
767 assert(util_bitcount(destMask
[buf
]) == 1);
768 if (fb
->_ColorDrawBufferIndexes
[buf
] != bufIndex
) {
769 updated_drawbuffers(ctx
, fb
);
770 fb
->_ColorDrawBufferIndexes
[buf
] = bufIndex
;
775 if (fb
->_ColorDrawBufferIndexes
[buf
] != BUFFER_NONE
) {
776 updated_drawbuffers(ctx
, fb
);
777 fb
->_ColorDrawBufferIndexes
[buf
] = BUFFER_NONE
;
780 fb
->ColorDrawBuffer
[buf
] = buffers
[buf
];
782 fb
->_NumColorDrawBuffers
= count
;
785 /* set remaining outputs to BUFFER_NONE */
786 for (buf
= fb
->_NumColorDrawBuffers
; buf
< ctx
->Const
.MaxDrawBuffers
; buf
++) {
787 if (fb
->_ColorDrawBufferIndexes
[buf
] != BUFFER_NONE
) {
788 updated_drawbuffers(ctx
, fb
);
789 fb
->_ColorDrawBufferIndexes
[buf
] = BUFFER_NONE
;
792 for (buf
= n
; buf
< ctx
->Const
.MaxDrawBuffers
; buf
++) {
793 fb
->ColorDrawBuffer
[buf
] = GL_NONE
;
796 if (_mesa_is_winsys_fbo(fb
)) {
797 /* also set context drawbuffer state */
798 for (buf
= 0; buf
< ctx
->Const
.MaxDrawBuffers
; buf
++) {
799 if (ctx
->Color
.DrawBuffer
[buf
] != fb
->ColorDrawBuffer
[buf
]) {
800 updated_drawbuffers(ctx
, fb
);
801 ctx
->Color
.DrawBuffer
[buf
] = fb
->ColorDrawBuffer
[buf
];
809 * Update the current drawbuffer's _ColorDrawBufferIndex[] list, etc.
810 * from the context's Color.DrawBuffer[] state.
811 * Use when changing contexts.
814 _mesa_update_draw_buffers(struct gl_context
*ctx
)
816 /* should be a window system FBO */
817 assert(_mesa_is_winsys_fbo(ctx
->DrawBuffer
));
819 _mesa_drawbuffers(ctx
, ctx
->DrawBuffer
, ctx
->Const
.MaxDrawBuffers
,
820 ctx
->Color
.DrawBuffer
, NULL
);
825 * Like \sa _mesa_drawbuffers(), this is a helper function for setting
826 * GL_READ_BUFFER state for the given context and FBO.
827 * Note that all error checking should have been done before calling
829 * \param ctx the rendering context
830 * \param fb the framebuffer object to update
831 * \param buffer GL_FRONT, GL_BACK, GL_COLOR_ATTACHMENT0, etc.
832 * \param bufferIndex the numerical index corresponding to 'buffer'
835 _mesa_readbuffer(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
836 GLenum buffer
, gl_buffer_index bufferIndex
)
838 if ((fb
== ctx
->ReadBuffer
) && _mesa_is_winsys_fbo(fb
)) {
839 /* Only update the per-context READ_BUFFER state if we're bound to
840 * a window-system framebuffer.
842 ctx
->Pixel
.ReadBuffer
= buffer
;
845 fb
->ColorReadBuffer
= buffer
;
846 fb
->_ColorReadBufferIndex
= bufferIndex
;
848 ctx
->NewState
|= _NEW_BUFFERS
;
854 * Called by glReadBuffer and glNamedFramebufferReadBuffer to set the source
855 * renderbuffer for reading pixels.
856 * \param mode color buffer such as GL_FRONT, GL_BACK, etc.
858 static ALWAYS_INLINE
void
859 read_buffer(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
860 GLenum buffer
, const char *caller
, bool no_error
)
862 gl_buffer_index srcBuffer
;
864 FLUSH_VERTICES(ctx
, 0);
866 if (MESA_VERBOSE
& VERBOSE_API
)
867 _mesa_debug(ctx
, "%s %s\n", caller
, _mesa_enum_to_string(buffer
));
869 if (buffer
== GL_NONE
) {
870 /* This is legal--it means that no buffer should be bound for reading. */
871 srcBuffer
= BUFFER_NONE
;
874 /* general case / window-system framebuffer */
875 if (!no_error
&&_mesa_is_gles3(ctx
) &&
876 !is_legal_es3_readbuffer_enum(buffer
))
877 srcBuffer
= BUFFER_NONE
;
879 srcBuffer
= read_buffer_enum_to_index(ctx
, buffer
);
882 GLbitfield supportedMask
;
884 if (srcBuffer
== BUFFER_NONE
) {
885 _mesa_error(ctx
, GL_INVALID_ENUM
,
886 "%s(invalid buffer %s)", caller
,
887 _mesa_enum_to_string(buffer
));
891 supportedMask
= supported_buffer_bitmask(ctx
, fb
);
892 if (((1 << srcBuffer
) & supportedMask
) == 0) {
893 _mesa_error(ctx
, GL_INVALID_OPERATION
,
894 "%s(invalid buffer %s)", caller
,
895 _mesa_enum_to_string(buffer
));
901 /* OK, all error checking has been completed now */
903 _mesa_readbuffer(ctx
, fb
, buffer
, srcBuffer
);
905 /* Call the device driver function only if fb is the bound read buffer */
906 if (fb
== ctx
->ReadBuffer
) {
907 if (ctx
->Driver
.ReadBuffer
)
908 ctx
->Driver
.ReadBuffer(ctx
, buffer
);
914 read_buffer_err(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
915 GLenum buffer
, const char *caller
)
917 read_buffer(ctx
, fb
, buffer
, caller
, false);
922 read_buffer_no_error(struct gl_context
*ctx
, struct gl_framebuffer
*fb
,
923 GLenum buffer
, const char *caller
)
925 read_buffer(ctx
, fb
, buffer
, caller
, true);
930 _mesa_ReadBuffer_no_error(GLenum buffer
)
932 GET_CURRENT_CONTEXT(ctx
);
933 read_buffer_no_error(ctx
, ctx
->ReadBuffer
, buffer
, "glReadBuffer");
938 _mesa_ReadBuffer(GLenum buffer
)
940 GET_CURRENT_CONTEXT(ctx
);
941 read_buffer_err(ctx
, ctx
->ReadBuffer
, buffer
, "glReadBuffer");
946 _mesa_NamedFramebufferReadBuffer_no_error(GLuint framebuffer
, GLenum src
)
948 GET_CURRENT_CONTEXT(ctx
);
950 struct gl_framebuffer
*fb
;
953 fb
= _mesa_lookup_framebuffer(ctx
, framebuffer
);
955 fb
= ctx
->WinSysReadBuffer
;
958 read_buffer_no_error(ctx
, fb
, src
, "glNamedFramebufferReadBuffer");
963 _mesa_NamedFramebufferReadBuffer(GLuint framebuffer
, GLenum src
)
965 GET_CURRENT_CONTEXT(ctx
);
966 struct gl_framebuffer
*fb
;
969 fb
= _mesa_lookup_framebuffer_err(ctx
, framebuffer
,
970 "glNamedFramebufferReadBuffer");
975 fb
= ctx
->WinSysReadBuffer
;
977 read_buffer_err(ctx
, fb
, src
, "glNamedFramebufferReadBuffer");