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authormarha <marha@users.sourceforge.net>2010-11-29 22:05:53 +0000
committermarha <marha@users.sourceforge.net>2010-11-29 22:05:53 +0000
commitfed109d6a33c0871291d1bb2f3f6b7a3d1a3e9d7 (patch)
treefa1ba494685a71e28a096990a8707680c7cb378b /mesalib/src/mesa/main/transformfeedback.c
parentae340911c1ba1f98b418bd8f1a487fa4d79491b0 (diff)
parent6fda93be42ace9eeab0e82ceebb6798961c9105c (diff)
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svn merge ^/branches/released .
Diffstat (limited to 'mesalib/src/mesa/main/transformfeedback.c')
-rw-r--r--mesalib/src/mesa/main/transformfeedback.c944
1 files changed, 944 insertions, 0 deletions
diff --git a/mesalib/src/mesa/main/transformfeedback.c b/mesalib/src/mesa/main/transformfeedback.c
new file mode 100644
index 000000000..5c8c1fd22
--- /dev/null
+++ b/mesalib/src/mesa/main/transformfeedback.c
@@ -0,0 +1,944 @@
+/*
+ * Mesa 3-D graphics library
+ *
+ * Copyright (C) 2010 VMware, Inc. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+/*
+ * Vertex transform feedback support.
+ *
+ * Authors:
+ * Brian Paul
+ */
+
+
+#include "buffers.h"
+#include "bufferobj.h"
+#include "context.h"
+#include "hash.h"
+#include "transformfeedback.h"
+#include "shaderapi.h"
+#include "shaderobj.h"
+#include "main/dispatch.h"
+
+#include "program/prog_parameter.h"
+//#include "program/shader_api.h"
+
+
+#if FEATURE_EXT_transform_feedback
+
+
+/**
+ * Do reference counting of transform feedback buffers.
+ */
+static void
+reference_transform_feedback_object(struct gl_transform_feedback_object **ptr,
+ struct gl_transform_feedback_object *obj)
+{
+ if (*ptr == obj)
+ return;
+
+ if (*ptr) {
+ /* Unreference the old object */
+ struct gl_transform_feedback_object *oldObj = *ptr;
+
+ ASSERT(oldObj->RefCount > 0);
+ oldObj->RefCount--;
+
+ if (oldObj->RefCount == 0) {
+ GET_CURRENT_CONTEXT(ctx);
+ if (ctx)
+ ctx->Driver.DeleteTransformFeedback(ctx, oldObj);
+ }
+
+ *ptr = NULL;
+ }
+ ASSERT(!*ptr);
+
+ if (obj) {
+ /* reference new object */
+ if (obj->RefCount == 0) {
+ _mesa_problem(NULL, "referencing deleted transform feedback object");
+ *ptr = NULL;
+ }
+ else {
+ obj->RefCount++;
+ *ptr = obj;
+ }
+ }
+}
+
+
+/**
+ * Check if the given primitive mode (as in glBegin(mode)) is compatible
+ * with the current transform feedback mode (if it's enabled).
+ * This is to be called from glBegin(), glDrawArrays(), glDrawElements(), etc.
+ *
+ * \return GL_TRUE if the mode is OK, GL_FALSE otherwise.
+ */
+GLboolean
+_mesa_validate_primitive_mode(GLcontext *ctx, GLenum mode)
+{
+ if (ctx->TransformFeedback.CurrentObject->Active) {
+ switch (mode) {
+ case GL_POINTS:
+ return ctx->TransformFeedback.Mode == GL_POINTS;
+ case GL_LINES:
+ case GL_LINE_STRIP:
+ case GL_LINE_LOOP:
+ return ctx->TransformFeedback.Mode == GL_LINES;
+ default:
+ return ctx->TransformFeedback.Mode == GL_TRIANGLES;
+ }
+ }
+ return GL_TRUE;
+}
+
+
+/**
+ * Check that all the buffer objects currently bound for transform
+ * feedback actually exist. Raise a GL_INVALID_OPERATION error if
+ * any buffers are missing.
+ * \return GL_TRUE for success, GL_FALSE if error
+ */
+GLboolean
+_mesa_validate_transform_feedback_buffers(GLcontext *ctx)
+{
+ /* XXX to do */
+ return GL_TRUE;
+}
+
+
+
+/**
+ * Per-context init for transform feedback.
+ */
+void
+_mesa_init_transform_feedback(GLcontext *ctx)
+{
+ /* core mesa expects this, even a dummy one, to be available */
+ ASSERT(ctx->Driver.NewTransformFeedback);
+
+ ctx->TransformFeedback.DefaultObject =
+ ctx->Driver.NewTransformFeedback(ctx, 0);
+
+ assert(ctx->TransformFeedback.DefaultObject->RefCount == 1);
+
+ reference_transform_feedback_object(&ctx->TransformFeedback.CurrentObject,
+ ctx->TransformFeedback.DefaultObject);
+
+ assert(ctx->TransformFeedback.DefaultObject->RefCount == 2);
+
+ ctx->TransformFeedback.Objects = _mesa_NewHashTable();
+
+ _mesa_reference_buffer_object(ctx,
+ &ctx->TransformFeedback.CurrentBuffer,
+ ctx->Shared->NullBufferObj);
+}
+
+
+
+/**
+ * Callback for _mesa_HashDeleteAll().
+ */
+static void
+delete_cb(GLuint key, void *data, void *userData)
+{
+ GLcontext *ctx = (GLcontext *) userData;
+ struct gl_transform_feedback_object *obj =
+ (struct gl_transform_feedback_object *) data;
+
+ ctx->Driver.DeleteTransformFeedback(ctx, obj);
+}
+
+
+/**
+ * Per-context free/clean-up for transform feedback.
+ */
+void
+_mesa_free_transform_feedback(GLcontext *ctx)
+{
+ /* core mesa expects this, even a dummy one, to be available */
+ ASSERT(ctx->Driver.NewTransformFeedback);
+
+ _mesa_reference_buffer_object(ctx,
+ &ctx->TransformFeedback.CurrentBuffer,
+ NULL);
+
+ /* Delete all feedback objects */
+ _mesa_HashDeleteAll(ctx->TransformFeedback.Objects, delete_cb, ctx);
+ _mesa_DeleteHashTable(ctx->TransformFeedback.Objects);
+
+ /* Delete the default feedback object */
+ assert(ctx->Driver.DeleteTransformFeedback);
+ ctx->Driver.DeleteTransformFeedback(ctx,
+ ctx->TransformFeedback.DefaultObject);
+
+ ctx->TransformFeedback.CurrentObject = NULL;
+}
+
+
+#else /* FEATURE_EXT_transform_feedback */
+
+/* forward declarations */
+static struct gl_transform_feedback_object *
+new_transform_feedback(GLcontext *ctx, GLuint name);
+
+static void
+delete_transform_feedback(GLcontext *ctx,
+ struct gl_transform_feedback_object *obj);
+
+/* dummy per-context init/clean-up for transform feedback */
+void
+_mesa_init_transform_feedback(GLcontext *ctx)
+{
+ ctx->TransformFeedback.DefaultObject = new_transform_feedback(ctx, 0);
+ ctx->TransformFeedback.CurrentObject = ctx->TransformFeedback.DefaultObject;
+ _mesa_reference_buffer_object(ctx,
+ &ctx->TransformFeedback.CurrentBuffer,
+ ctx->Shared->NullBufferObj);
+}
+
+void
+_mesa_free_transform_feedback(GLcontext *ctx)
+{
+ _mesa_reference_buffer_object(ctx,
+ &ctx->TransformFeedback.CurrentBuffer,
+ NULL);
+ ctx->TransformFeedback.CurrentObject = NULL;
+ delete_transform_feedback(ctx, ctx->TransformFeedback.DefaultObject);
+}
+
+#endif /* FEATURE_EXT_transform_feedback */
+
+
+/** Default fallback for ctx->Driver.NewTransformFeedback() */
+static struct gl_transform_feedback_object *
+new_transform_feedback(GLcontext *ctx, GLuint name)
+{
+ struct gl_transform_feedback_object *obj;
+ obj = CALLOC_STRUCT(gl_transform_feedback_object);
+ if (obj) {
+ obj->Name = name;
+ obj->RefCount = 1;
+ }
+ return obj;
+}
+
+/** Default fallback for ctx->Driver.DeleteTransformFeedback() */
+static void
+delete_transform_feedback(GLcontext *ctx,
+ struct gl_transform_feedback_object *obj)
+{
+ GLuint i;
+
+ for (i = 0; i < Elements(obj->Buffers); i++) {
+ _mesa_reference_buffer_object(ctx, &obj->Buffers[i], NULL);
+ }
+
+ free(obj);
+}
+
+
+#if FEATURE_EXT_transform_feedback
+
+
+/** Default fallback for ctx->Driver.BeginTransformFeedback() */
+static void
+begin_transform_feedback(GLcontext *ctx, GLenum mode,
+ struct gl_transform_feedback_object *obj)
+{
+ /* nop */
+}
+
+/** Default fallback for ctx->Driver.EndTransformFeedback() */
+static void
+end_transform_feedback(GLcontext *ctx,
+ struct gl_transform_feedback_object *obj)
+{
+ /* nop */
+}
+
+/** Default fallback for ctx->Driver.PauseTransformFeedback() */
+static void
+pause_transform_feedback(GLcontext *ctx,
+ struct gl_transform_feedback_object *obj)
+{
+ /* nop */
+}
+
+/** Default fallback for ctx->Driver.ResumeTransformFeedback() */
+static void
+resume_transform_feedback(GLcontext *ctx,
+ struct gl_transform_feedback_object *obj)
+{
+ /* nop */
+}
+
+/** Default fallback for ctx->Driver.DrawTransformFeedback() */
+static void
+draw_transform_feedback(GLcontext *ctx, GLenum mode,
+ struct gl_transform_feedback_object *obj)
+{
+ /* XXX to do */
+ /*
+ * Get number of vertices in obj's feedback buffer.
+ * Call ctx->Exec.DrawArrays(mode, 0, count);
+ */
+}
+
+
+/**
+ * Plug in default device driver functions for transform feedback.
+ * Most drivers will override some/all of these.
+ */
+void
+_mesa_init_transform_feedback_functions(struct dd_function_table *driver)
+{
+ driver->NewTransformFeedback = new_transform_feedback;
+ driver->DeleteTransformFeedback = delete_transform_feedback;
+ driver->BeginTransformFeedback = begin_transform_feedback;
+ driver->EndTransformFeedback = end_transform_feedback;
+ driver->PauseTransformFeedback = pause_transform_feedback;
+ driver->ResumeTransformFeedback = resume_transform_feedback;
+ driver->DrawTransformFeedback = draw_transform_feedback;
+}
+
+
+void
+_mesa_init_transform_feedback_dispatch(struct _glapi_table *disp)
+{
+ SET_BeginTransformFeedbackEXT(disp, _mesa_BeginTransformFeedback);
+ SET_EndTransformFeedbackEXT(disp, _mesa_EndTransformFeedback);
+ SET_BindBufferRangeEXT(disp, _mesa_BindBufferRange);
+ SET_BindBufferBaseEXT(disp, _mesa_BindBufferBase);
+ SET_BindBufferOffsetEXT(disp, _mesa_BindBufferOffsetEXT);
+ SET_TransformFeedbackVaryingsEXT(disp, _mesa_TransformFeedbackVaryings);
+ SET_GetTransformFeedbackVaryingEXT(disp, _mesa_GetTransformFeedbackVarying);
+}
+
+
+/**
+ ** Begin API functions
+ **/
+
+
+void GLAPIENTRY
+_mesa_BeginTransformFeedback(GLenum mode)
+{
+ struct gl_transform_feedback_object *obj;
+ GET_CURRENT_CONTEXT(ctx);
+
+ obj = ctx->TransformFeedback.CurrentObject;
+
+ switch (mode) {
+ case GL_POINTS:
+ case GL_LINES:
+ case GL_TRIANGLES:
+ /* legal */
+ break;
+ default:
+ _mesa_error(ctx, GL_INVALID_ENUM, "glBeginTransformFeedback(mode)");
+ return;
+ }
+
+ if (obj->Active) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBeginTransformFeedback(already active)");
+ return;
+ }
+
+ obj->Active = GL_TRUE;
+ ctx->TransformFeedback.Mode = mode;
+
+ assert(ctx->Driver.BeginTransformFeedback);
+ ctx->Driver.BeginTransformFeedback(ctx, mode, obj);
+}
+
+
+void GLAPIENTRY
+_mesa_EndTransformFeedback(void)
+{
+ struct gl_transform_feedback_object *obj;
+ GET_CURRENT_CONTEXT(ctx);
+
+ obj = ctx->TransformFeedback.CurrentObject;
+
+ if (!obj->Active) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glEndTransformFeedback(not active)");
+ return;
+ }
+
+ ctx->TransformFeedback.CurrentObject->Active = GL_FALSE;
+
+ assert(ctx->Driver.EndTransformFeedback);
+ ctx->Driver.EndTransformFeedback(ctx, obj);
+}
+
+
+/**
+ * Helper used by BindBufferRange() and BindBufferBase().
+ */
+static void
+bind_buffer_range(GLcontext *ctx, GLuint index,
+ struct gl_buffer_object *bufObj,
+ GLintptr offset, GLsizeiptr size)
+{
+ struct gl_transform_feedback_object *obj =
+ ctx->TransformFeedback.CurrentObject;
+
+ /* The general binding point */
+ _mesa_reference_buffer_object(ctx,
+ &ctx->TransformFeedback.CurrentBuffer,
+ bufObj);
+
+ /* The per-attribute binding point */
+ _mesa_reference_buffer_object(ctx,
+ &obj->Buffers[index],
+ bufObj);
+
+ obj->BufferNames[index] = bufObj->Name;
+
+ obj->Offset[index] = offset;
+ obj->Size[index] = size;
+}
+
+
+/**
+ * Specify a buffer object to receive vertex shader results. Plus,
+ * specify the starting offset to place the results, and max size.
+ */
+void GLAPIENTRY
+_mesa_BindBufferRange(GLenum target, GLuint index,
+ GLuint buffer, GLintptr offset, GLsizeiptr size)
+{
+ struct gl_transform_feedback_object *obj;
+ struct gl_buffer_object *bufObj;
+ GET_CURRENT_CONTEXT(ctx);
+
+ if (target != GL_TRANSFORM_FEEDBACK_BUFFER) {
+ _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferRange(target)");
+ return;
+ }
+
+ obj = ctx->TransformFeedback.CurrentObject;
+
+ if (obj->Active) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindBufferRange(transform feedback active)");
+ return;
+ }
+
+ if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+ _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(index=%d)", index);
+ return;
+ }
+
+ if ((size <= 0) || (size & 0x3)) {
+ /* must be positive and multiple of four */
+ _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(size%d)", (int) size);
+ return;
+ }
+
+ if (offset & 0x3) {
+ /* must be multiple of four */
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glBindBufferRange(offset=%d)", (int) offset);
+ return;
+ }
+
+ bufObj = _mesa_lookup_bufferobj(ctx, buffer);
+ if (!bufObj) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindBufferRange(invalid buffer=%u)", buffer);
+ return;
+ }
+
+ if (offset + size >= bufObj->Size) {
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glBindBufferRange(offset + size %d > buffer size %d)",
+ (int) (offset + size), (int) (bufObj->Size));
+ return;
+ }
+
+ bind_buffer_range(ctx, index, bufObj, offset, size);
+}
+
+
+/**
+ * Specify a buffer object to receive vertex shader results.
+ * As above, but start at offset = 0.
+ */
+void GLAPIENTRY
+_mesa_BindBufferBase(GLenum target, GLuint index, GLuint buffer)
+{
+ struct gl_transform_feedback_object *obj;
+ struct gl_buffer_object *bufObj;
+ GLsizeiptr size;
+ GET_CURRENT_CONTEXT(ctx);
+
+ if (target != GL_TRANSFORM_FEEDBACK_BUFFER) {
+ _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferBase(target)");
+ return;
+ }
+
+ obj = ctx->TransformFeedback.CurrentObject;
+
+ if (obj->Active) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindBufferRange(transform feedback active)");
+ return;
+ }
+
+ if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+ _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferBase(index=%d)", index);
+ return;
+ }
+
+ bufObj = _mesa_lookup_bufferobj(ctx, buffer);
+ if (!bufObj) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindBufferBase(invalid buffer=%u)", buffer);
+ return;
+ }
+
+ /* default size is the buffer size rounded down to nearest
+ * multiple of four.
+ */
+ size = bufObj->Size & ~0x3;
+
+ bind_buffer_range(ctx, index, bufObj, 0, size);
+}
+
+
+/**
+ * Specify a buffer object to receive vertex shader results, plus the
+ * offset in the buffer to start placing results.
+ * This function is part of GL_EXT_transform_feedback, but not GL3.
+ */
+void GLAPIENTRY
+_mesa_BindBufferOffsetEXT(GLenum target, GLuint index, GLuint buffer,
+ GLintptr offset)
+{
+ struct gl_transform_feedback_object *obj;
+ struct gl_buffer_object *bufObj;
+ GET_CURRENT_CONTEXT(ctx);
+ GLsizeiptr size;
+
+ if (target != GL_TRANSFORM_FEEDBACK_BUFFER) {
+ _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferOffsetEXT(target)");
+ return;
+ }
+
+ obj = ctx->TransformFeedback.CurrentObject;
+
+ if (obj->Active) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindBufferRange(transform feedback active)");
+ return;
+ }
+
+ if (index >= ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glBindBufferOffsetEXT(index=%d)", index);
+ return;
+ }
+
+ bufObj = _mesa_lookup_bufferobj(ctx, buffer);
+ if (!bufObj) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindBufferOffsetEXT(invalid buffer=%u)", buffer);
+ return;
+ }
+
+ /* default size is the buffer size rounded down to nearest
+ * multiple of four.
+ */
+ size = (bufObj->Size - offset) & ~0x3;
+
+ bind_buffer_range(ctx, index, bufObj, offset, size);
+}
+
+
+/**
+ * This function specifies the vertex shader outputs to be written
+ * to the feedback buffer(s), and in what order.
+ */
+void GLAPIENTRY
+_mesa_TransformFeedbackVaryings(GLuint program, GLsizei count,
+ const GLchar **varyings, GLenum bufferMode)
+{
+ struct gl_shader_program *shProg;
+ GLuint i;
+ GET_CURRENT_CONTEXT(ctx);
+
+ switch (bufferMode) {
+ case GL_INTERLEAVED_ATTRIBS:
+ break;
+ case GL_SEPARATE_ATTRIBS:
+ break;
+ default:
+ _mesa_error(ctx, GL_INVALID_ENUM,
+ "glTransformFeedbackVaryings(bufferMode)");
+ return;
+ }
+
+ if (count < 0 || count > ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glTransformFeedbackVaryings(count=%d)", count);
+ return;
+ }
+
+ shProg = _mesa_lookup_shader_program(ctx, program);
+ if (!shProg) {
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glTransformFeedbackVaryings(program=%u)", program);
+ return;
+ }
+
+ /* free existing varyings, if any */
+ for (i = 0; i < shProg->TransformFeedback.NumVarying; i++) {
+ free(shProg->TransformFeedback.VaryingNames[i]);
+ }
+ free(shProg->TransformFeedback.VaryingNames);
+
+ /* allocate new memory for varying names */
+ shProg->TransformFeedback.VaryingNames =
+ (GLchar **) malloc(count * sizeof(GLchar *));
+
+ if (!shProg->TransformFeedback.VaryingNames) {
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glTransformFeedbackVaryings()");
+ return;
+ }
+
+ /* Save the new names and the count */
+ for (i = 0; i < (GLuint) count; i++) {
+ shProg->TransformFeedback.VaryingNames[i] = _mesa_strdup(varyings[i]);
+ }
+ shProg->TransformFeedback.NumVarying = count;
+
+ shProg->TransformFeedback.BufferMode = bufferMode;
+
+ /* The varyings won't be used until shader link time */
+}
+
+
+/**
+ * Get info about the vertex shader's outputs which are to be written
+ * to the feedback buffer(s).
+ */
+void GLAPIENTRY
+_mesa_GetTransformFeedbackVarying(GLuint program, GLuint index,
+ GLsizei bufSize, GLsizei *length,
+ GLsizei *size, GLenum *type, GLchar *name)
+{
+ const struct gl_shader_program *shProg;
+ const GLchar *varyingName;
+ GLint v;
+ GET_CURRENT_CONTEXT(ctx);
+
+ shProg = _mesa_lookup_shader_program(ctx, program);
+ if (!shProg) {
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glGetTransformFeedbackVaryings(program=%u)", program);
+ return;
+ }
+
+ if (index >= shProg->TransformFeedback.NumVarying) {
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glGetTransformFeedbackVaryings(index=%u)", index);
+ return;
+ }
+
+ varyingName = shProg->TransformFeedback.VaryingNames[index];
+
+ v = _mesa_lookup_parameter_index(shProg->Varying, -1, varyingName);
+ if (v >= 0) {
+ struct gl_program_parameter *param = &shProg->Varying->Parameters[v];
+
+ /* return the varying's name and length */
+ _mesa_copy_string(name, bufSize, length, varyingName);
+
+ /* return the datatype and value's size (in datatype units) */
+ if (type)
+ *type = param->DataType;
+ if (size)
+ *size = param->Size;
+ }
+ else {
+ name[0] = 0;
+ if (length)
+ *length = 0;
+ if (type)
+ *type = 0;
+ if (size)
+ *size = 0;
+ }
+}
+
+
+
+static struct gl_transform_feedback_object *
+lookup_transform_feedback_object(GLcontext *ctx, GLuint name)
+{
+ if (name == 0) {
+ return ctx->TransformFeedback.DefaultObject;
+ }
+ else
+ return (struct gl_transform_feedback_object *)
+ _mesa_HashLookup(ctx->TransformFeedback.Objects, name);
+}
+
+
+/**
+ * Create new transform feedback objects. Transform feedback objects
+ * encapsulate the state related to transform feedback to allow quickly
+ * switching state (and drawing the results, below).
+ * Part of GL_ARB_transform_feedback2.
+ */
+void GLAPIENTRY
+_mesa_GenTransformFeedbacks(GLsizei n, GLuint *names)
+{
+ GLuint first;
+ GET_CURRENT_CONTEXT(ctx);
+
+ ASSERT_OUTSIDE_BEGIN_END(ctx);
+
+ if (n < 0) {
+ _mesa_error(ctx, GL_INVALID_VALUE, "glGenTransformFeedbacks(n < 0)");
+ return;
+ }
+
+ if (!names)
+ return;
+
+ /* we don't need contiguous IDs, but this might be faster */
+ first = _mesa_HashFindFreeKeyBlock(ctx->TransformFeedback.Objects, n);
+ if (first) {
+ GLsizei i;
+ for (i = 0; i < n; i++) {
+ struct gl_transform_feedback_object *obj
+ = ctx->Driver.NewTransformFeedback(ctx, first + i);
+ if (!obj) {
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGenTransformFeedbacks");
+ return;
+ }
+ names[i] = first + i;
+ _mesa_HashInsert(ctx->TransformFeedback.Objects, first + i, obj);
+ }
+ }
+ else {
+ _mesa_error(ctx, GL_OUT_OF_MEMORY, "glGenTransformFeedbacks");
+ }
+}
+
+
+/**
+ * Is the given ID a transform feedback object?
+ * Part of GL_ARB_transform_feedback2.
+ */
+GLboolean GLAPIENTRY
+_mesa_IsTransformFeedback(GLuint name)
+{
+ GET_CURRENT_CONTEXT(ctx);
+
+ ASSERT_OUTSIDE_BEGIN_END_WITH_RETVAL(ctx, GL_FALSE);
+
+ if (name && lookup_transform_feedback_object(ctx, name))
+ return GL_TRUE;
+ else
+ return GL_FALSE;
+}
+
+
+/**
+ * Bind the given transform feedback object.
+ * Part of GL_ARB_transform_feedback2.
+ */
+void GLAPIENTRY
+_mesa_BindTransformFeedback(GLenum target, GLuint name)
+{
+ struct gl_transform_feedback_object *obj;
+ GET_CURRENT_CONTEXT(ctx);
+
+ if (target != GL_TRANSFORM_FEEDBACK) {
+ _mesa_error(ctx, GL_INVALID_ENUM, "glBindTransformFeedback(target)");
+ return;
+ }
+
+ if (ctx->TransformFeedback.CurrentObject->Active &&
+ !ctx->TransformFeedback.CurrentObject->Paused) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindTransformFeedback(transform is active, or not paused)");
+ return;
+ }
+
+ obj = lookup_transform_feedback_object(ctx, name);
+ if (!obj) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glBindTransformFeedback(name=%u)", name);
+ return;
+ }
+
+ reference_transform_feedback_object(&ctx->TransformFeedback.CurrentObject,
+ obj);
+}
+
+
+/**
+ * Delete the given transform feedback objects.
+ * Part of GL_ARB_transform_feedback2.
+ */
+void GLAPIENTRY
+_mesa_DeleteTransformFeedbacks(GLsizei n, const GLuint *names)
+{
+ GLint i;
+ GET_CURRENT_CONTEXT(ctx);
+
+ ASSERT_OUTSIDE_BEGIN_END(ctx);
+
+ if (n < 0) {
+ _mesa_error(ctx, GL_INVALID_VALUE, "glDeleteTransformFeedbacks(n < 0)");
+ return;
+ }
+
+ if (!names)
+ return;
+
+ for (i = 0; i < n; i++) {
+ if (names[i] > 0) {
+ struct gl_transform_feedback_object *obj
+ = lookup_transform_feedback_object(ctx, names[i]);
+ if (obj) {
+ if (obj->Active) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glDeleteTransformFeedbacks(object %u is active)",
+ names[i]);
+ return;
+ }
+ _mesa_HashRemove(ctx->TransformFeedback.Objects, names[i]);
+ /* unref, but object may not be deleted until later */
+ reference_transform_feedback_object(&obj, NULL);
+ }
+ }
+ }
+}
+
+
+/**
+ * Pause transform feedback.
+ * Part of GL_ARB_transform_feedback2.
+ */
+void GLAPIENTRY
+_mesa_PauseTransformFeedback(void)
+{
+ struct gl_transform_feedback_object *obj;
+ GET_CURRENT_CONTEXT(ctx);
+
+ obj = ctx->TransformFeedback.CurrentObject;
+
+ if (!obj->Active || obj->Paused) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glPauseTransformFeedback(feedback not active or already paused)");
+ return;
+ }
+
+ obj->Paused = GL_TRUE;
+
+ assert(ctx->Driver.PauseTransformFeedback);
+ ctx->Driver.PauseTransformFeedback(ctx, obj);
+}
+
+
+/**
+ * Resume transform feedback.
+ * Part of GL_ARB_transform_feedback2.
+ */
+void GLAPIENTRY
+_mesa_ResumeTransformFeedback(void)
+{
+ struct gl_transform_feedback_object *obj;
+ GET_CURRENT_CONTEXT(ctx);
+
+ obj = ctx->TransformFeedback.CurrentObject;
+
+ if (!obj->Active || !obj->Paused) {
+ _mesa_error(ctx, GL_INVALID_OPERATION,
+ "glPauseTransformFeedback(feedback not active or not paused)");
+ return;
+ }
+
+ obj->Paused = GL_FALSE;
+
+ assert(ctx->Driver.ResumeTransformFeedback);
+ ctx->Driver.ResumeTransformFeedback(ctx, obj);
+}
+
+
+/**
+ * Draw the vertex data in a transform feedback object.
+ * \param mode GL_POINTS, GL_LINES, GL_TRIANGLE_STRIP, etc.
+ * \param name the transform feedback object
+ * The number of vertices comes from the transform feedback object.
+ * User still has to setup of the vertex attribute info with
+ * glVertexPointer, glColorPointer, etc.
+ * Part of GL_ARB_transform_feedback2.
+ */
+void GLAPIENTRY
+_mesa_DrawTransformFeedback(GLenum mode, GLuint name)
+{
+ GET_CURRENT_CONTEXT(ctx);
+ struct gl_transform_feedback_object *obj =
+ lookup_transform_feedback_object(ctx, name);
+
+ if (mode > GL_POLYGON) {
+ _mesa_error(ctx, GL_INVALID_ENUM,
+ "glDrawTransformFeedback(mode=0x%x)", mode);
+ return;
+ }
+ if (!obj) {
+ _mesa_error(ctx, GL_INVALID_VALUE,
+ "glDrawTransformFeedback(name = %u)", name);
+ return;
+ }
+
+ /* XXX check if EndTransformFeedback has never been called while
+ * the object was bound
+ */
+
+ assert(ctx->Driver.DrawTransformFeedback);
+ ctx->Driver.DrawTransformFeedback(ctx, mode, obj);
+}
+
+
+/*
+XXX misc to do:
+
+glGet*() for
+
+GL_TRANSFORM_FEEDBACK_BUFFER_PAUSED
+GL_TRANSFORM_FEEDBACK_BUFFER_ACTIVE
+GL_TRANSFORM_FEEDBACK_BINDING
+*/
+
+
+#endif /* FEATURE_EXT_transform_feedback */