X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=src%2Fmesa%2Fmain%2Ftransformfeedback.c;h=d02b6a056a57f29779021513ae2c267e91efcf93;hb=bebb0438113efdcc1c2aaed95c70ba87de1d3053;hp=74519ba38a6d40cd6dfc5dfc633f2e9dea8bd2e9;hpb=ff20543c815a14fddad1efaaef1610454a1924d4;p=mesa.git

diff --git a/src/mesa/main/transformfeedback.c b/src/mesa/main/transformfeedback.c
index 74519ba38a6..d02b6a056a5 100644
--- a/src/mesa/main/transformfeedback.c
+++ b/src/mesa/main/transformfeedback.c
@@ -33,35 +33,58 @@
 #include "buffers.h"
 #include "bufferobj.h"
 #include "context.h"
+#include "hash.h"
+#include "mfeatures.h"
+#include "mtypes.h"
 #include "transformfeedback.h"
+#include "shaderapi.h"
+#include "shaderobj.h"
+#include "main/dispatch.h"
 
-#include "shader/prog_parameter.h"
-#include "shader/shader_api.h"
+#include "program/prog_parameter.h"
+
+
+#if FEATURE_EXT_transform_feedback
 
 
 /**
- * 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.
+ * Do reference counting of transform feedback buffers.
  */
-GLboolean
-_mesa_validate_primitive_mode(GLcontext *ctx, GLenum mode)
+static void
+reference_transform_feedback_object(struct gl_transform_feedback_object **ptr,
+                                    struct gl_transform_feedback_object *obj)
 {
-   if (ctx->TransformFeedback.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;
+   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;
       }
    }
-   return GL_TRUE;
 }
 
 
@@ -72,9 +95,9 @@ _mesa_validate_primitive_mode(GLcontext *ctx, GLenum mode)
  * \return GL_TRUE for success, GL_FALSE if error
  */
 GLboolean
-_mesa_validate_transform_feedback_buffers(GLcontext *ctx)
+_mesa_validate_transform_feedback_buffers(struct gl_context *ctx)
 {
-
+   /* XXX to do */
    return GL_TRUE;
 }
 
@@ -84,31 +107,232 @@ _mesa_validate_transform_feedback_buffers(GLcontext *ctx)
  * Per-context init for transform feedback.
  */
 void
-_mesa_init_transform_feedback(GLcontext *ctx)
+_mesa_init_transform_feedback(struct gl_context *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)
+{
+   struct gl_context *ctx = (struct gl_context *) 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)
+_mesa_free_transform_feedback(struct gl_context *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(struct gl_context *ctx, GLuint name);
+
+static void
+delete_transform_feedback(struct gl_context *ctx,
+                          struct gl_transform_feedback_object *obj);
+
+/* dummy per-context init/clean-up for transform feedback */
+void
+_mesa_init_transform_feedback(struct gl_context *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(struct gl_context *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(struct gl_context *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(struct gl_context *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(struct gl_context *ctx, GLenum mode,
+                         struct gl_transform_feedback_object *obj)
+{
+   /* nop */
+}
+
+/** Default fallback for ctx->Driver.EndTransformFeedback() */
+static void
+end_transform_feedback(struct gl_context *ctx,
+                       struct gl_transform_feedback_object *obj)
+{
+   /* nop */
+}
+
+/** Default fallback for ctx->Driver.PauseTransformFeedback() */
+static void
+pause_transform_feedback(struct gl_context *ctx,
+                         struct gl_transform_feedback_object *obj)
+{
+   /* nop */
+}
+
+/** Default fallback for ctx->Driver.ResumeTransformFeedback() */
+static void
+resume_transform_feedback(struct gl_context *ctx,
+                          struct gl_transform_feedback_object *obj)
+{
+   /* nop */
+}
+
+
+/**
+ * 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;
+}
+
+
+void
+_mesa_init_transform_feedback_dispatch(struct _glapi_table *disp)
+{
+   /* EXT_transform_feedback */
+   SET_BeginTransformFeedbackEXT(disp, _mesa_BeginTransformFeedback);
+   SET_EndTransformFeedbackEXT(disp, _mesa_EndTransformFeedback);
+   SET_BindBufferOffsetEXT(disp, _mesa_BindBufferOffsetEXT);
+   SET_TransformFeedbackVaryingsEXT(disp, _mesa_TransformFeedbackVaryings);
+   SET_GetTransformFeedbackVaryingEXT(disp, _mesa_GetTransformFeedbackVarying);
+   /* ARB_transform_feedback2 */
+   SET_BindTransformFeedback(disp, _mesa_BindTransformFeedback);
+   SET_DeleteTransformFeedbacks(disp, _mesa_DeleteTransformFeedbacks);
+   SET_GenTransformFeedbacks(disp, _mesa_GenTransformFeedbacks);
+   SET_IsTransformFeedback(disp, _mesa_IsTransformFeedback);
+   SET_PauseTransformFeedback(disp, _mesa_PauseTransformFeedback);
+   SET_ResumeTransformFeedback(disp, _mesa_ResumeTransformFeedback);
+}
+
+
+/**
+ ** Begin API functions
+ **/
+
 
 void GLAPIENTRY
 _mesa_BeginTransformFeedback(GLenum mode)
 {
+   struct gl_transform_feedback_object *obj;
+   struct gl_transform_feedback_info *info;
+   int i;
    GET_CURRENT_CONTEXT(ctx);
 
+   obj = ctx->TransformFeedback.CurrentObject;
+
+   if (ctx->Shader.CurrentVertexProgram == NULL) {
+      _mesa_error(ctx, GL_INVALID_OPERATION,
+                  "glBeginTransformFeedback(no program active)");
+      return;
+   }
+
+   info = &ctx->Shader.CurrentVertexProgram->LinkedTransformFeedback;
+
+   if (info->NumOutputs == 0) {
+      _mesa_error(ctx, GL_INVALID_OPERATION,
+                  "glBeginTransformFeedback(no varyings to record)");
+      return;
+   }
+
    switch (mode) {
    case GL_POINTS:
    case GL_LINES:
@@ -120,29 +344,51 @@ _mesa_BeginTransformFeedback(GLenum mode)
       return;
    }
 
-   if (ctx->TransformFeedback.Active) {
+   if (obj->Active) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
                   "glBeginTransformFeedback(already active)");
       return;
    }
 
-   ctx->TransformFeedback.Active = GL_TRUE;
+   for (i = 0; i < info->NumBuffers; ++i) {
+      if (obj->BufferNames[i] == 0) {
+         _mesa_error(ctx, GL_INVALID_OPERATION,
+                     "glBeginTransformFeedback(binding point %d does not have "
+                     "a buffer object bound)", i);
+         return;
+      }
+   }
+
+   FLUSH_VERTICES(ctx, _NEW_TRANSFORM_FEEDBACK);
+   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);
 
-   if (!ctx->TransformFeedback.Active) {
+   obj = ctx->TransformFeedback.CurrentObject;
+
+   if (!obj->Active) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
                   "glEndTransformFeedback(not active)");
       return;
    }
 
-   ctx->TransformFeedback.Active = GL_FALSE;
+   FLUSH_VERTICES(ctx, _NEW_TRANSFORM_FEEDBACK);
+   ctx->TransformFeedback.CurrentObject->Active = GL_FALSE;
+   ctx->TransformFeedback.CurrentObject->Paused = GL_FALSE;
+   ctx->TransformFeedback.CurrentObject->EndedAnytime = GL_TRUE;
+
+   assert(ctx->Driver.EndTransformFeedback);
+   ctx->Driver.EndTransformFeedback(ctx, obj);
 }
 
 
@@ -150,10 +396,18 @@ _mesa_EndTransformFeedback(void)
  * Helper used by BindBufferRange() and BindBufferBase().
  */
 static void
-bind_buffer_range(GLcontext *ctx, GLuint index,
+bind_buffer_range(struct gl_context *ctx, GLuint index,
                   struct gl_buffer_object *bufObj,
                   GLintptr offset, GLsizeiptr size)
 {
+   struct gl_transform_feedback_object *obj =
+      ctx->TransformFeedback.CurrentObject;
+
+   /* Note: no need to FLUSH_VERTICES or flag _NEW_TRANSFORM_FEEDBACK, because
+    * transform feedback buffers can't be changed while transform feedback is
+    * active.
+    */
+
    /* The general binding point */
    _mesa_reference_buffer_object(ctx,
                                  &ctx->TransformFeedback.CurrentBuffer,
@@ -161,33 +415,33 @@ bind_buffer_range(GLcontext *ctx, GLuint index,
 
    /* The per-attribute binding point */
    _mesa_reference_buffer_object(ctx,
-                                 &ctx->TransformFeedback.Buffers[index],
+                                 &obj->Buffers[index],
                                  bufObj);
 
-   ctx->TransformFeedback.BufferNames[index] = bufObj->Name;
+   obj->BufferNames[index] = bufObj->Name;
 
-   ctx->TransformFeedback.Offset[index] = offset;
-   ctx->TransformFeedback.Size[index] = size;
+   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.
+ * Called from the glBindBufferRange() function.
  */
-void GLAPIENTRY
-_mesa_BindBufferRange(GLenum target, GLuint index,
-                      GLuint buffer, GLintptr offset, GLsizeiptr size)
+void
+_mesa_bind_buffer_range_transform_feedback(struct gl_context *ctx,
+					   GLuint index,
+					   struct gl_buffer_object *bufObj,
+					   GLintptr offset,
+					   GLsizeiptr size)
 {
-   struct gl_buffer_object *bufObj;
-   GET_CURRENT_CONTEXT(ctx);
+   struct gl_transform_feedback_object *obj;
 
-   if (target != GL_TRANSFORM_FEEDBACK_BUFFER) {
-      _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferRange(target)");
-      return;
-   }
+   obj = ctx->TransformFeedback.CurrentObject;
 
-   if (ctx->TransformFeedback.Active) {
+   if (obj->Active) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
                   "glBindBufferRange(transform feedback active)");
       return;
@@ -198,29 +452,16 @@ _mesa_BindBufferRange(GLenum target, GLuint index,
       return;
    }
 
-   if ((size <= 0) || (size & 0x3)) {
-      /* must be positive and multiple of four */
-      _mesa_error(ctx, GL_INVALID_VALUE, "glBindBufferRange(size%d)", size);
+   if (size & 0x3) {
+      /* must a 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)", 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 > buffer size)", size);
+                  "glBindBufferRange(offset=%d)", (int) offset);
       return;
    }  
 
@@ -231,22 +472,21 @@ _mesa_BindBufferRange(GLenum target, GLuint index,
 /**
  * Specify a buffer object to receive vertex shader results.
  * As above, but start at offset = 0.
+ * Called from the glBindBufferBase() function.
  */
-void GLAPIENTRY
-_mesa_BindBufferBase(GLenum target, GLuint index, GLuint buffer)
+void
+_mesa_bind_buffer_base_transform_feedback(struct gl_context *ctx,
+					  GLuint index,
+					  struct gl_buffer_object *bufObj)
 {
-   struct gl_buffer_object *bufObj;
-   GET_CURRENT_CONTEXT(ctx);
+   struct gl_transform_feedback_object *obj;
    GLsizeiptr size;
 
-   if (target != GL_TRANSFORM_FEEDBACK_BUFFER) {
-      _mesa_error(ctx, GL_INVALID_ENUM, "glBindBufferBase(target)");
-      return;
-   }
+   obj = ctx->TransformFeedback.CurrentObject;
 
-   if (ctx->TransformFeedback.Active) {
+   if (obj->Active) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
-                  "glBindBufferRange(transform feedback active)");
+                  "glBindBufferBase(transform feedback active)");
       return;
    }
 
@@ -255,13 +495,6 @@ _mesa_BindBufferBase(GLenum target, GLuint index, GLuint buffer)
       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.
     */
@@ -280,6 +513,7 @@ 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;
@@ -289,9 +523,11 @@ _mesa_BindBufferOffsetEXT(GLenum target, GLuint index, GLuint buffer,
       return;
    }
 
-   if (ctx->TransformFeedback.Active) {
+   obj = ctx->TransformFeedback.CurrentObject;
+
+   if (obj->Active) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
-                  "glBindBufferRange(transform feedback active)");
+                  "glBindBufferOffsetEXT(transform feedback active)");
       return;
    }
 
@@ -301,7 +537,19 @@ _mesa_BindBufferOffsetEXT(GLenum target, GLuint index, GLuint buffer,
       return;
    }
 
-   bufObj = _mesa_lookup_bufferobj(ctx, buffer);
+   if (offset & 0x3) {
+      /* must be multiple of four */
+      _mesa_error(ctx, GL_INVALID_VALUE,
+                  "glBindBufferOffsetEXT(offset=%d)", (int) offset);
+      return;
+   }
+
+   if (buffer == 0) {
+      bufObj = ctx->Shared->NullBufferObj;
+   } else {
+      bufObj = _mesa_lookup_bufferobj(ctx, buffer);
+   }
+
    if (!bufObj) {
       _mesa_error(ctx, GL_INVALID_OPERATION,
                   "glBindBufferOffsetEXT(invalid buffer=%u)", buffer);
@@ -340,7 +588,9 @@ _mesa_TransformFeedbackVaryings(GLuint program, GLsizei count,
       return;
    }
 
-   if (count < 0 || count > ctx->Const.MaxTransformFeedbackSeparateAttribs) {
+   if (count < 0 ||
+       (bufferMode == GL_SEPARATE_ATTRIBS &&
+        (GLuint) count > ctx->Const.MaxTransformFeedbackSeparateAttribs)) {
       _mesa_error(ctx, GL_INVALID_VALUE,
                   "glTransformFeedbackVaryings(count=%d)", count);
       return;
@@ -376,7 +626,9 @@ _mesa_TransformFeedbackVaryings(GLuint program, GLsizei count,
 
    shProg->TransformFeedback.BufferMode = bufferMode;
 
-   /* The varyings won't be used until shader link time */
+   /* No need to set _NEW_TRANSFORM_FEEDBACK (or invoke FLUSH_VERTICES) since
+    * the varyings won't be used until shader link time.
+    */
 }
 
 
@@ -390,8 +642,7 @@ _mesa_GetTransformFeedbackVarying(GLuint program, GLuint index,
                                   GLsizei *size, GLenum *type, GLchar *name)
 {
    const struct gl_shader_program *shProg;
-   const GLchar *varyingName;
-   GLint v;
+   const struct gl_transform_feedback_info *linked_xfb_info;
    GET_CURRENT_CONTEXT(ctx);
 
    shProg = _mesa_lookup_shader_program(ctx, program);
@@ -401,35 +652,222 @@ _mesa_GetTransformFeedbackVarying(GLuint program, GLuint index,
       return;
    }
 
-   if (index >= shProg->TransformFeedback.NumVarying) {
+   linked_xfb_info = &shProg->LinkedTransformFeedback;
+   if (index >= linked_xfb_info->NumVarying) {
       _mesa_error(ctx, GL_INVALID_VALUE,
                   "glGetTransformFeedbackVaryings(index=%u)", index);
       return;
    }
 
-   varyingName = shProg->TransformFeedback.VaryingNames[index];
+   /* return the varying's name and length */
+   _mesa_copy_string(name, bufSize, length,
+		     linked_xfb_info->Varyings[index].Name);
 
-   v = _mesa_lookup_parameter_index(shProg->Varying, -1, varyingName);
-   if (v >= 0) {
-      struct gl_program_parameter *param = &shProg->Varying->Parameters[v];
+   /* return the datatype and value's size (in datatype units) */
+   if (type)
+      *type = linked_xfb_info->Varyings[index].Type;
+   if (size)
+      *size = linked_xfb_info->Varyings[index].Size;
+}
+
+
+
+struct gl_transform_feedback_object *
+_mesa_lookup_transform_feedback_object(struct gl_context *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;
+   }
 
-      /* return the varying's name and length */
-      _mesa_copy_string(name, bufSize, length, varyingName);
+   if (!names)
+      return;
 
-      /* return the datatype and value's size (in datatype units) */
-      if (type)
-         *type = param->DataType;
-      if (size)
-         *size = param->Size;
+   /* 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 {
-      name[0] = 0;
-      if (length)
-         *length = 0;
-      if (type)
-         *type = 0;
-      if (size)
-         *size = 0;
+      _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 && _mesa_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 = _mesa_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
+            = _mesa_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;
+   }
+
+   FLUSH_VERTICES(ctx, _NEW_TRANSFORM_FEEDBACK);
+   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,
+               "glResumeTransformFeedback(feedback not active or not paused)");
+      return;
    }
+
+   FLUSH_VERTICES(ctx, _NEW_TRANSFORM_FEEDBACK);
+   obj->Paused = GL_FALSE;
+
+   assert(ctx->Driver.ResumeTransformFeedback);
+   ctx->Driver.ResumeTransformFeedback(ctx, obj);
 }
 
+#endif /* FEATURE_EXT_transform_feedback */