2 * Mesa 3-D graphics library
4 * Copyright (C) 2010 VMware, Inc. 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.
27 * Transform feedback support.
35 #include "bufferobj.h"
40 #include "transformfeedback.h"
41 #include "shaderapi.h"
42 #include "shaderobj.h"
43 #include "main/dispatch.h"
45 #include "program/prog_parameter.h"
47 struct using_program_tuple
49 struct gl_shader_program
*shProg
;
54 active_xfb_object_references_program(GLuint key
, void *data
, void *user_data
)
56 struct using_program_tuple
*callback_data
= user_data
;
57 struct gl_transform_feedback_object
*obj
= data
;
58 if (obj
->Active
&& obj
->shader_program
== callback_data
->shProg
)
59 callback_data
->found
= true;
63 * Return true if any active transform feedback object is using a program.
66 _mesa_transform_feedback_is_using_program(struct gl_context
*ctx
,
67 struct gl_shader_program
*shProg
)
69 struct using_program_tuple callback_data
;
70 callback_data
.shProg
= shProg
;
71 callback_data
.found
= false;
73 _mesa_HashWalk(ctx
->TransformFeedback
.Objects
,
74 active_xfb_object_references_program
, &callback_data
);
76 /* Also check DefaultObject, as it's not in the Objects hash table. */
77 active_xfb_object_references_program(0, ctx
->TransformFeedback
.DefaultObject
,
80 return callback_data
.found
;
84 * Do reference counting of transform feedback buffers.
87 reference_transform_feedback_object(struct gl_transform_feedback_object
**ptr
,
88 struct gl_transform_feedback_object
*obj
)
94 /* Unreference the old object */
95 struct gl_transform_feedback_object
*oldObj
= *ptr
;
97 ASSERT(oldObj
->RefCount
> 0);
100 if (oldObj
->RefCount
== 0) {
101 GET_CURRENT_CONTEXT(ctx
);
103 ctx
->Driver
.DeleteTransformFeedback(ctx
, oldObj
);
111 /* reference new object */
112 if (obj
->RefCount
== 0) {
113 _mesa_problem(NULL
, "referencing deleted transform feedback object");
118 obj
->EverBound
= GL_TRUE
;
126 * Check that all the buffer objects currently bound for transform
127 * feedback actually exist. Raise a GL_INVALID_OPERATION error if
128 * any buffers are missing.
129 * \return GL_TRUE for success, GL_FALSE if error
132 _mesa_validate_transform_feedback_buffers(struct gl_context
*ctx
)
141 * Per-context init for transform feedback.
144 _mesa_init_transform_feedback(struct gl_context
*ctx
)
146 /* core mesa expects this, even a dummy one, to be available */
147 ASSERT(ctx
->Driver
.NewTransformFeedback
);
149 ctx
->TransformFeedback
.DefaultObject
=
150 ctx
->Driver
.NewTransformFeedback(ctx
, 0);
152 assert(ctx
->TransformFeedback
.DefaultObject
->RefCount
== 1);
154 reference_transform_feedback_object(&ctx
->TransformFeedback
.CurrentObject
,
155 ctx
->TransformFeedback
.DefaultObject
);
157 assert(ctx
->TransformFeedback
.DefaultObject
->RefCount
== 2);
159 ctx
->TransformFeedback
.Objects
= _mesa_NewHashTable();
161 _mesa_reference_buffer_object(ctx
,
162 &ctx
->TransformFeedback
.CurrentBuffer
,
163 ctx
->Shared
->NullBufferObj
);
169 * Callback for _mesa_HashDeleteAll().
172 delete_cb(GLuint key
, void *data
, void *userData
)
174 struct gl_context
*ctx
= (struct gl_context
*) userData
;
175 struct gl_transform_feedback_object
*obj
=
176 (struct gl_transform_feedback_object
*) data
;
178 ctx
->Driver
.DeleteTransformFeedback(ctx
, obj
);
183 * Per-context free/clean-up for transform feedback.
186 _mesa_free_transform_feedback(struct gl_context
*ctx
)
188 /* core mesa expects this, even a dummy one, to be available */
189 ASSERT(ctx
->Driver
.NewTransformFeedback
);
191 _mesa_reference_buffer_object(ctx
,
192 &ctx
->TransformFeedback
.CurrentBuffer
,
195 /* Delete all feedback objects */
196 _mesa_HashDeleteAll(ctx
->TransformFeedback
.Objects
, delete_cb
, ctx
);
197 _mesa_DeleteHashTable(ctx
->TransformFeedback
.Objects
);
199 /* Delete the default feedback object */
200 assert(ctx
->Driver
.DeleteTransformFeedback
);
201 ctx
->Driver
.DeleteTransformFeedback(ctx
,
202 ctx
->TransformFeedback
.DefaultObject
);
204 ctx
->TransformFeedback
.CurrentObject
= NULL
;
208 /** Initialize the fields of a gl_transform_feedback_object. */
210 _mesa_init_transform_feedback_object(struct gl_transform_feedback_object
*obj
,
218 obj
->EverBound
= GL_FALSE
;
222 /** Default fallback for ctx->Driver.NewTransformFeedback() */
223 static struct gl_transform_feedback_object
*
224 new_transform_feedback(struct gl_context
*ctx
, GLuint name
)
226 struct gl_transform_feedback_object
*obj
;
227 obj
= CALLOC_STRUCT(gl_transform_feedback_object
);
228 _mesa_init_transform_feedback_object(obj
, name
);
232 /** Default fallback for ctx->Driver.DeleteTransformFeedback() */
234 delete_transform_feedback(struct gl_context
*ctx
,
235 struct gl_transform_feedback_object
*obj
)
239 for (i
= 0; i
< Elements(obj
->Buffers
); i
++) {
240 _mesa_reference_buffer_object(ctx
, &obj
->Buffers
[i
], NULL
);
248 /** Default fallback for ctx->Driver.BeginTransformFeedback() */
250 begin_transform_feedback(struct gl_context
*ctx
, GLenum mode
,
251 struct gl_transform_feedback_object
*obj
)
256 /** Default fallback for ctx->Driver.EndTransformFeedback() */
258 end_transform_feedback(struct gl_context
*ctx
,
259 struct gl_transform_feedback_object
*obj
)
264 /** Default fallback for ctx->Driver.PauseTransformFeedback() */
266 pause_transform_feedback(struct gl_context
*ctx
,
267 struct gl_transform_feedback_object
*obj
)
272 /** Default fallback for ctx->Driver.ResumeTransformFeedback() */
274 resume_transform_feedback(struct gl_context
*ctx
,
275 struct gl_transform_feedback_object
*obj
)
282 * Plug in default device driver functions for transform feedback.
283 * Most drivers will override some/all of these.
286 _mesa_init_transform_feedback_functions(struct dd_function_table
*driver
)
288 driver
->NewTransformFeedback
= new_transform_feedback
;
289 driver
->DeleteTransformFeedback
= delete_transform_feedback
;
290 driver
->BeginTransformFeedback
= begin_transform_feedback
;
291 driver
->EndTransformFeedback
= end_transform_feedback
;
292 driver
->PauseTransformFeedback
= pause_transform_feedback
;
293 driver
->ResumeTransformFeedback
= resume_transform_feedback
;
298 * Fill in the correct Size value for each buffer in \c obj.
300 * From the GL 4.3 spec, section 6.1.1 ("Binding Buffer Objects to Indexed
303 * BindBufferBase binds the entire buffer, even when the size of the buffer
304 * is changed after the binding is established. It is equivalent to calling
305 * BindBufferRange with offset zero, while size is determined by the size of
306 * the bound buffer at the time the binding is used.
308 * Regardless of the size specified with BindBufferRange, or indirectly with
309 * BindBufferBase, the GL will never read or write beyond the end of a bound
310 * buffer. In some cases this constraint may result in visibly different
311 * behavior when a buffer overflow would otherwise result, such as described
312 * for transform feedback operations in section 13.2.2.
315 compute_transform_feedback_buffer_sizes(
316 struct gl_transform_feedback_object
*obj
)
319 for (i
= 0; i
< MAX_FEEDBACK_BUFFERS
; ++i
) {
320 GLintptr offset
= obj
->Offset
[i
];
321 GLsizeiptr buffer_size
322 = obj
->Buffers
[i
] == NULL
? 0 : obj
->Buffers
[i
]->Size
;
323 GLsizeiptr available_space
324 = buffer_size
<= offset
? 0 : buffer_size
- offset
;
325 GLsizeiptr computed_size
;
326 if (obj
->RequestedSize
[i
] == 0) {
327 /* No size was specified at the time the buffer was bound, so allow
328 * writing to all available space in the buffer.
330 computed_size
= available_space
;
332 /* A size was specified at the time the buffer was bound, however
333 * it's possible that the buffer has shrunk since then. So only
334 * allow writing to the minimum of the specified size and the space
337 computed_size
= MIN2(available_space
, obj
->RequestedSize
[i
]);
340 /* Legal sizes must be multiples of four, so round down if necessary. */
341 obj
->Size
[i
] = computed_size
& ~0x3;
347 * Compute the maximum number of vertices that can be written to the currently
348 * enabled transform feedback buffers without overflowing any of them.
351 _mesa_compute_max_transform_feedback_vertices(
352 const struct gl_transform_feedback_object
*obj
,
353 const struct gl_transform_feedback_info
*info
)
355 unsigned max_index
= 0xffffffff;
358 for (i
= 0; i
< info
->NumBuffers
; ++i
) {
359 unsigned stride
= info
->BufferStride
[i
];
360 unsigned max_for_this_buffer
;
362 /* Skip any inactive buffers, which have a stride of 0. */
366 max_for_this_buffer
= obj
->Size
[i
] / (4 * stride
);
367 max_index
= MIN2(max_index
, max_for_this_buffer
);
375 ** Begin API functions
380 * Figure out which stage of the pipeline is the source of transform feedback
381 * data given the current context state, and return its gl_shader_program.
383 * If no active program can generate transform feedback data (i.e. no vertex
384 * shader is active), returns NULL.
386 static struct gl_shader_program
*
387 get_xfb_source(struct gl_context
*ctx
)
390 for (i
= MESA_SHADER_GEOMETRY
; i
>= MESA_SHADER_VERTEX
; i
--) {
391 if (ctx
->Shader
.CurrentProgram
[i
] != NULL
)
392 return ctx
->Shader
.CurrentProgram
[i
];
399 _mesa_BeginTransformFeedback(GLenum mode
)
401 struct gl_transform_feedback_object
*obj
;
402 struct gl_transform_feedback_info
*info
= NULL
;
403 struct gl_shader_program
*source
;
405 unsigned vertices_per_prim
;
406 GET_CURRENT_CONTEXT(ctx
);
408 obj
= ctx
->TransformFeedback
.CurrentObject
;
410 /* Figure out what pipeline stage is the source of data for transform
413 source
= get_xfb_source(ctx
);
414 if (source
== NULL
) {
415 _mesa_error(ctx
, GL_INVALID_OPERATION
,
416 "glBeginTransformFeedback(no program active)");
420 info
= &source
->LinkedTransformFeedback
;
422 if (info
->NumOutputs
== 0) {
423 _mesa_error(ctx
, GL_INVALID_OPERATION
,
424 "glBeginTransformFeedback(no varyings to record)");
430 vertices_per_prim
= 1;
433 vertices_per_prim
= 2;
436 vertices_per_prim
= 3;
439 _mesa_error(ctx
, GL_INVALID_ENUM
, "glBeginTransformFeedback(mode)");
444 _mesa_error(ctx
, GL_INVALID_OPERATION
,
445 "glBeginTransformFeedback(already active)");
449 for (i
= 0; i
< info
->NumBuffers
; ++i
) {
450 if (obj
->BufferNames
[i
] == 0) {
451 _mesa_error(ctx
, GL_INVALID_OPERATION
,
452 "glBeginTransformFeedback(binding point %d does not have "
453 "a buffer object bound)", i
);
458 FLUSH_VERTICES(ctx
, 0);
459 ctx
->NewDriverState
|= ctx
->DriverFlags
.NewTransformFeedback
;
461 obj
->Active
= GL_TRUE
;
462 ctx
->TransformFeedback
.Mode
= mode
;
464 compute_transform_feedback_buffer_sizes(obj
);
466 if (_mesa_is_gles3(ctx
)) {
467 /* In GLES3, we are required to track the usage of the transform
468 * feedback buffer and report INVALID_OPERATION if a draw call tries to
469 * exceed it. So compute the maximum number of vertices that we can
470 * write without overflowing any of the buffers currently being used for
473 unsigned max_vertices
474 = _mesa_compute_max_transform_feedback_vertices(obj
, info
);
475 obj
->GlesRemainingPrims
= max_vertices
/ vertices_per_prim
;
478 if (obj
->shader_program
!= source
) {
479 ctx
->NewDriverState
|= ctx
->DriverFlags
.NewTransformFeedbackProg
;
480 obj
->shader_program
= source
;
483 assert(ctx
->Driver
.BeginTransformFeedback
);
484 ctx
->Driver
.BeginTransformFeedback(ctx
, mode
, obj
);
489 _mesa_EndTransformFeedback(void)
491 struct gl_transform_feedback_object
*obj
;
492 GET_CURRENT_CONTEXT(ctx
);
494 obj
= ctx
->TransformFeedback
.CurrentObject
;
497 _mesa_error(ctx
, GL_INVALID_OPERATION
,
498 "glEndTransformFeedback(not active)");
502 FLUSH_VERTICES(ctx
, 0);
503 ctx
->NewDriverState
|= ctx
->DriverFlags
.NewTransformFeedback
;
505 ctx
->TransformFeedback
.CurrentObject
->Active
= GL_FALSE
;
506 ctx
->TransformFeedback
.CurrentObject
->Paused
= GL_FALSE
;
507 ctx
->TransformFeedback
.CurrentObject
->EndedAnytime
= GL_TRUE
;
509 assert(ctx
->Driver
.EndTransformFeedback
);
510 ctx
->Driver
.EndTransformFeedback(ctx
, obj
);
515 * Helper used by BindBufferRange() and BindBufferBase().
518 bind_buffer_range(struct gl_context
*ctx
, GLuint index
,
519 struct gl_buffer_object
*bufObj
,
520 GLintptr offset
, GLsizeiptr size
)
522 struct gl_transform_feedback_object
*obj
=
523 ctx
->TransformFeedback
.CurrentObject
;
525 /* Note: no need to FLUSH_VERTICES or flag NewTransformFeedback, because
526 * transform feedback buffers can't be changed while transform feedback is
530 /* The general binding point */
531 _mesa_reference_buffer_object(ctx
,
532 &ctx
->TransformFeedback
.CurrentBuffer
,
535 /* The per-attribute binding point */
536 _mesa_reference_buffer_object(ctx
,
537 &obj
->Buffers
[index
],
540 obj
->BufferNames
[index
] = bufObj
->Name
;
542 obj
->Offset
[index
] = offset
;
543 obj
->RequestedSize
[index
] = size
;
548 * Specify a buffer object to receive transform feedback results. Plus,
549 * specify the starting offset to place the results, and max size.
550 * Called from the glBindBufferRange() function.
553 _mesa_bind_buffer_range_transform_feedback(struct gl_context
*ctx
,
555 struct gl_buffer_object
*bufObj
,
559 struct gl_transform_feedback_object
*obj
;
561 obj
= ctx
->TransformFeedback
.CurrentObject
;
564 _mesa_error(ctx
, GL_INVALID_OPERATION
,
565 "glBindBufferRange(transform feedback active)");
569 if (index
>= ctx
->Const
.MaxTransformFeedbackBuffers
) {
570 _mesa_error(ctx
, GL_INVALID_VALUE
, "glBindBufferRange(index=%d)", index
);
575 /* must a multiple of four */
576 _mesa_error(ctx
, GL_INVALID_VALUE
, "glBindBufferRange(size=%d)", (int) size
);
581 /* must be multiple of four */
582 _mesa_error(ctx
, GL_INVALID_VALUE
,
583 "glBindBufferRange(offset=%d)", (int) offset
);
587 bind_buffer_range(ctx
, index
, bufObj
, offset
, size
);
592 * Specify a buffer object to receive transform feedback results.
593 * As above, but start at offset = 0.
594 * Called from the glBindBufferBase() function.
597 _mesa_bind_buffer_base_transform_feedback(struct gl_context
*ctx
,
599 struct gl_buffer_object
*bufObj
)
601 struct gl_transform_feedback_object
*obj
;
603 obj
= ctx
->TransformFeedback
.CurrentObject
;
606 _mesa_error(ctx
, GL_INVALID_OPERATION
,
607 "glBindBufferBase(transform feedback active)");
611 if (index
>= ctx
->Const
.MaxTransformFeedbackBuffers
) {
612 _mesa_error(ctx
, GL_INVALID_VALUE
, "glBindBufferBase(index=%d)", index
);
616 bind_buffer_range(ctx
, index
, bufObj
, 0, 0);
621 * Specify a buffer object to receive transform feedback results, plus the
622 * offset in the buffer to start placing results.
623 * This function is part of GL_EXT_transform_feedback, but not GL3.
626 _mesa_BindBufferOffsetEXT(GLenum target
, GLuint index
, GLuint buffer
,
629 struct gl_transform_feedback_object
*obj
;
630 struct gl_buffer_object
*bufObj
;
631 GET_CURRENT_CONTEXT(ctx
);
633 if (target
!= GL_TRANSFORM_FEEDBACK_BUFFER
) {
634 _mesa_error(ctx
, GL_INVALID_ENUM
, "glBindBufferOffsetEXT(target)");
638 obj
= ctx
->TransformFeedback
.CurrentObject
;
641 _mesa_error(ctx
, GL_INVALID_OPERATION
,
642 "glBindBufferOffsetEXT(transform feedback active)");
646 if (index
>= ctx
->Const
.MaxTransformFeedbackBuffers
) {
647 _mesa_error(ctx
, GL_INVALID_VALUE
,
648 "glBindBufferOffsetEXT(index=%d)", index
);
653 /* must be multiple of four */
654 _mesa_error(ctx
, GL_INVALID_VALUE
,
655 "glBindBufferOffsetEXT(offset=%d)", (int) offset
);
660 bufObj
= ctx
->Shared
->NullBufferObj
;
662 bufObj
= _mesa_lookup_bufferobj(ctx
, buffer
);
666 _mesa_error(ctx
, GL_INVALID_OPERATION
,
667 "glBindBufferOffsetEXT(invalid buffer=%u)", buffer
);
671 bind_buffer_range(ctx
, index
, bufObj
, offset
, 0);
676 * This function specifies the transform feedback outputs to be written
677 * to the feedback buffer(s), and in what order.
680 _mesa_TransformFeedbackVaryings(GLuint program
, GLsizei count
,
681 const GLchar
* const *varyings
,
684 struct gl_shader_program
*shProg
;
686 GET_CURRENT_CONTEXT(ctx
);
688 /* From the ARB_transform_feedback2 specification:
689 * "The error INVALID_OPERATION is generated by TransformFeedbackVaryings
690 * if the current transform feedback object is active, even if paused."
692 if (ctx
->TransformFeedback
.CurrentObject
->Active
) {
693 _mesa_error(ctx
, GL_INVALID_OPERATION
,
694 "glTransformFeedbackVaryings(current object is active)");
698 switch (bufferMode
) {
699 case GL_INTERLEAVED_ATTRIBS
:
701 case GL_SEPARATE_ATTRIBS
:
704 _mesa_error(ctx
, GL_INVALID_ENUM
,
705 "glTransformFeedbackVaryings(bufferMode)");
710 (bufferMode
== GL_SEPARATE_ATTRIBS
&&
711 (GLuint
) count
> ctx
->Const
.MaxTransformFeedbackBuffers
)) {
712 _mesa_error(ctx
, GL_INVALID_VALUE
,
713 "glTransformFeedbackVaryings(count=%d)", count
);
717 shProg
= _mesa_lookup_shader_program(ctx
, program
);
719 _mesa_error(ctx
, GL_INVALID_VALUE
,
720 "glTransformFeedbackVaryings(program=%u)", program
);
724 if (ctx
->Extensions
.ARB_transform_feedback3
) {
725 if (bufferMode
== GL_INTERLEAVED_ATTRIBS
) {
726 unsigned buffers
= 1;
728 for (i
= 0; i
< count
; i
++) {
729 if (strcmp(varyings
[i
], "gl_NextBuffer") == 0)
733 if (buffers
> ctx
->Const
.MaxTransformFeedbackBuffers
) {
734 _mesa_error(ctx
, GL_INVALID_OPERATION
,
735 "glTransformFeedbackVaryings(too many gl_NextBuffer "
740 for (i
= 0; i
< count
; i
++) {
741 if (strcmp(varyings
[i
], "gl_NextBuffer") == 0 ||
742 strcmp(varyings
[i
], "gl_SkipComponents1") == 0 ||
743 strcmp(varyings
[i
], "gl_SkipComponents2") == 0 ||
744 strcmp(varyings
[i
], "gl_SkipComponents3") == 0 ||
745 strcmp(varyings
[i
], "gl_SkipComponents4") == 0) {
746 _mesa_error(ctx
, GL_INVALID_OPERATION
,
747 "glTransformFeedbackVaryings(SEPARATE_ATTRIBS,"
756 /* free existing varyings, if any */
757 for (i
= 0; i
< (GLint
) shProg
->TransformFeedback
.NumVarying
; i
++) {
758 free(shProg
->TransformFeedback
.VaryingNames
[i
]);
760 free(shProg
->TransformFeedback
.VaryingNames
);
762 /* allocate new memory for varying names */
763 shProg
->TransformFeedback
.VaryingNames
=
764 malloc(count
* sizeof(GLchar
*));
766 if (!shProg
->TransformFeedback
.VaryingNames
) {
767 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "glTransformFeedbackVaryings()");
771 /* Save the new names and the count */
772 for (i
= 0; i
< count
; i
++) {
773 shProg
->TransformFeedback
.VaryingNames
[i
] = _mesa_strdup(varyings
[i
]);
775 shProg
->TransformFeedback
.NumVarying
= count
;
777 shProg
->TransformFeedback
.BufferMode
= bufferMode
;
779 /* No need to invoke FLUSH_VERTICES or flag NewTransformFeedback since
780 * the varyings won't be used until shader link time.
786 * Get info about the transform feedback outputs which are to be written
787 * to the feedback buffer(s).
790 _mesa_GetTransformFeedbackVarying(GLuint program
, GLuint index
,
791 GLsizei bufSize
, GLsizei
*length
,
792 GLsizei
*size
, GLenum
*type
, GLchar
*name
)
794 const struct gl_shader_program
*shProg
;
795 const struct gl_transform_feedback_info
*linked_xfb_info
;
796 GET_CURRENT_CONTEXT(ctx
);
798 shProg
= _mesa_lookup_shader_program(ctx
, program
);
800 _mesa_error(ctx
, GL_INVALID_VALUE
,
801 "glGetTransformFeedbackVarying(program=%u)", program
);
805 linked_xfb_info
= &shProg
->LinkedTransformFeedback
;
806 if (index
>= (GLuint
) linked_xfb_info
->NumVarying
) {
807 _mesa_error(ctx
, GL_INVALID_VALUE
,
808 "glGetTransformFeedbackVarying(index=%u)", index
);
812 /* return the varying's name and length */
813 _mesa_copy_string(name
, bufSize
, length
,
814 linked_xfb_info
->Varyings
[index
].Name
);
816 /* return the datatype and value's size (in datatype units) */
818 *type
= linked_xfb_info
->Varyings
[index
].Type
;
820 *size
= linked_xfb_info
->Varyings
[index
].Size
;
825 struct gl_transform_feedback_object
*
826 _mesa_lookup_transform_feedback_object(struct gl_context
*ctx
, GLuint name
)
829 return ctx
->TransformFeedback
.DefaultObject
;
832 return (struct gl_transform_feedback_object
*)
833 _mesa_HashLookup(ctx
->TransformFeedback
.Objects
, name
);
838 * Create new transform feedback objects. Transform feedback objects
839 * encapsulate the state related to transform feedback to allow quickly
840 * switching state (and drawing the results, below).
841 * Part of GL_ARB_transform_feedback2.
844 _mesa_GenTransformFeedbacks(GLsizei n
, GLuint
*names
)
847 GET_CURRENT_CONTEXT(ctx
);
850 _mesa_error(ctx
, GL_INVALID_VALUE
, "glGenTransformFeedbacks(n < 0)");
857 /* we don't need contiguous IDs, but this might be faster */
858 first
= _mesa_HashFindFreeKeyBlock(ctx
->TransformFeedback
.Objects
, n
);
861 for (i
= 0; i
< n
; i
++) {
862 struct gl_transform_feedback_object
*obj
863 = ctx
->Driver
.NewTransformFeedback(ctx
, first
+ i
);
865 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "glGenTransformFeedbacks");
868 names
[i
] = first
+ i
;
869 _mesa_HashInsert(ctx
->TransformFeedback
.Objects
, first
+ i
, obj
);
873 _mesa_error(ctx
, GL_OUT_OF_MEMORY
, "glGenTransformFeedbacks");
879 * Is the given ID a transform feedback object?
880 * Part of GL_ARB_transform_feedback2.
883 _mesa_IsTransformFeedback(GLuint name
)
885 struct gl_transform_feedback_object
*obj
;
886 GET_CURRENT_CONTEXT(ctx
);
888 ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx
, GL_FALSE
);
893 obj
= _mesa_lookup_transform_feedback_object(ctx
, name
);
897 return obj
->EverBound
;
902 * Bind the given transform feedback object.
903 * Part of GL_ARB_transform_feedback2.
906 _mesa_BindTransformFeedback(GLenum target
, GLuint name
)
908 struct gl_transform_feedback_object
*obj
;
909 GET_CURRENT_CONTEXT(ctx
);
911 if (target
!= GL_TRANSFORM_FEEDBACK
) {
912 _mesa_error(ctx
, GL_INVALID_ENUM
, "glBindTransformFeedback(target)");
916 if (_mesa_is_xfb_active_and_unpaused(ctx
)) {
917 _mesa_error(ctx
, GL_INVALID_OPERATION
,
918 "glBindTransformFeedback(transform is active, or not paused)");
922 obj
= _mesa_lookup_transform_feedback_object(ctx
, name
);
924 _mesa_error(ctx
, GL_INVALID_OPERATION
,
925 "glBindTransformFeedback(name=%u)", name
);
929 reference_transform_feedback_object(&ctx
->TransformFeedback
.CurrentObject
,
935 * Delete the given transform feedback objects.
936 * Part of GL_ARB_transform_feedback2.
939 _mesa_DeleteTransformFeedbacks(GLsizei n
, const GLuint
*names
)
942 GET_CURRENT_CONTEXT(ctx
);
945 _mesa_error(ctx
, GL_INVALID_VALUE
, "glDeleteTransformFeedbacks(n < 0)");
952 for (i
= 0; i
< n
; i
++) {
954 struct gl_transform_feedback_object
*obj
955 = _mesa_lookup_transform_feedback_object(ctx
, names
[i
]);
958 _mesa_error(ctx
, GL_INVALID_OPERATION
,
959 "glDeleteTransformFeedbacks(object %u is active)",
963 _mesa_HashRemove(ctx
->TransformFeedback
.Objects
, names
[i
]);
964 /* unref, but object may not be deleted until later */
965 reference_transform_feedback_object(&obj
, NULL
);
973 * Pause transform feedback.
974 * Part of GL_ARB_transform_feedback2.
977 _mesa_PauseTransformFeedback(void)
979 struct gl_transform_feedback_object
*obj
;
980 GET_CURRENT_CONTEXT(ctx
);
982 obj
= ctx
->TransformFeedback
.CurrentObject
;
984 if (!_mesa_is_xfb_active_and_unpaused(ctx
)) {
985 _mesa_error(ctx
, GL_INVALID_OPERATION
,
986 "glPauseTransformFeedback(feedback not active or already paused)");
990 FLUSH_VERTICES(ctx
, 0);
991 ctx
->NewDriverState
|= ctx
->DriverFlags
.NewTransformFeedback
;
993 obj
->Paused
= GL_TRUE
;
995 assert(ctx
->Driver
.PauseTransformFeedback
);
996 ctx
->Driver
.PauseTransformFeedback(ctx
, obj
);
1001 * Resume transform feedback.
1002 * Part of GL_ARB_transform_feedback2.
1005 _mesa_ResumeTransformFeedback(void)
1007 struct gl_transform_feedback_object
*obj
;
1008 GET_CURRENT_CONTEXT(ctx
);
1010 obj
= ctx
->TransformFeedback
.CurrentObject
;
1012 if (!obj
->Active
|| !obj
->Paused
) {
1013 _mesa_error(ctx
, GL_INVALID_OPERATION
,
1014 "glResumeTransformFeedback(feedback not active or not paused)");
1018 /* From the ARB_transform_feedback2 specification:
1019 * "The error INVALID_OPERATION is generated by ResumeTransformFeedback if
1020 * the program object being used by the current transform feedback object
1023 if (obj
->shader_program
!= get_xfb_source(ctx
)) {
1024 _mesa_error(ctx
, GL_INVALID_OPERATION
,
1025 "glResumeTransformFeedback(wrong program bound)");
1029 FLUSH_VERTICES(ctx
, 0);
1030 ctx
->NewDriverState
|= ctx
->DriverFlags
.NewTransformFeedback
;
1032 obj
->Paused
= GL_FALSE
;
1034 assert(ctx
->Driver
.ResumeTransformFeedback
);
1035 ctx
->Driver
.ResumeTransformFeedback(ctx
, obj
);