Implement TransformFeedbackManager in GPU command buffer.

gpu/command_buffer/service/transform_feedback_manager.cc

Index: gpu/command_buffer/service/transform_feedback_manager.cc
diff --git a/gpu/command_buffer/service/transform_feedback_manager.cc b/gpu/command_buffer/service/transform_feedback_manager.cc
new file mode 100644
index 0000000000000000000000000000000000000000..e474c0bc07baf69eb65dac5056ac713f9ecbeee8
--- /dev/null
+++ b/gpu/command_buffer/service/transform_feedback_manager.cc
@@ -0,0 +1,125 @@
+// Copyright (c) 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "gpu/command_buffer/service/transform_feedback_manager.h"
+
+#include "gpu/command_buffer/service/buffer_manager.h"
+#include "ui/gl/gl_version_info.h"
+
+namespace gpu {
+namespace gles2 {
+
+TransformFeedback::TransformFeedback(TransformFeedbackManager* manager,
+                                     GLuint service_id)
+    : IndexedBufferBindingHost(
+          manager->max_transform_feedback_separate_attribs(),
+          manager->needs_emulation()),
+      manager_(manager),
+      service_id_(service_id),
+      has_been_bound_(false),
+      active_(false),
+      paused_(false),
+      primitive_mode_(GL_NONE) {
+  DCHECK_LT(0u, service_id);
+}
+
+TransformFeedback::~TransformFeedback() {
+  if (!manager_->lost_context()) {
+    glDeleteTransformFeedbacks(1, &service_id_);
+  }
+}
+
+void TransformFeedback::DoBindTransformFeedback(GLenum target) {
+  DCHECK_LT(0u, service_id_);
+  glBindTransformFeedback(target, service_id_);
+  has_been_bound_ = true;
+  OnBindHost(target);
+  if (active_ && !paused_) {
+    // This could only happen during virtual context switching.
+    // Otherwise the validation should generate a GL error without calling
+    // into this function.
+    glResumeTransformFeedback();
+  }
+}
+
+void TransformFeedback::DoBeginTransformFeedback(GLenum primitive_mode) {
+  DCHECK(!active_);
+  DCHECK(primitive_mode == GL_POINTS ||
+         primitive_mode == GL_LINES ||
+         primitive_mode == GL_TRIANGLES);
+  glBeginTransformFeedback(primitive_mode);
+  active_ = true;
+  primitive_mode_ = primitive_mode;
+}
+
+void TransformFeedback::DoEndTransformFeedback() {
+  DCHECK(active_);
+  glEndTransformFeedback();
+  active_ = false;
+  paused_ = false;
+}
+
+void TransformFeedback::DoPauseTransformFeedback() {
+  DCHECK(active_ && !paused_);
+  glPauseTransformFeedback();
+  paused_ = true;
+}
+
+void TransformFeedback::DoResumeTransformFeedback() {
+  DCHECK(active_ && paused_);
+  glResumeTransformFeedback();
+  paused_ = false;
+}
+
+
+TransformFeedbackManager::TransformFeedbackManager(
+    GLuint max_transform_feedback_separate_attribs, bool needs_emulation)
+    : max_transform_feedback_separate_attribs_(
+          max_transform_feedback_separate_attribs),
+      needs_emulation_(needs_emulation),
+      lost_context_(false) {
+}
+
+TransformFeedbackManager::~TransformFeedbackManager() {
+  DCHECK(transform_feedbacks_.empty());
+}
+
+void TransformFeedbackManager::Destroy() {
+  transform_feedbacks_.clear();
+}
+
+TransformFeedback* TransformFeedbackManager::CreateTransformFeedback(
+    GLuint client_id, GLuint service_id) {
+  scoped_refptr<TransformFeedback> transform_feedback(
+      new TransformFeedback(this, service_id));
+  auto result = transform_feedbacks_.insert(
+      std::make_pair(client_id, transform_feedback));
+  DCHECK(result.second);
+  return result.first->second.get();
+}
+
+TransformFeedback* TransformFeedbackManager::GetTransformFeedback(
+    GLuint client_id) {
+  if (client_id == 0) {
+    return nullptr;
+  }
+  auto it = transform_feedbacks_.find(client_id);
+  return it != transform_feedbacks_.end() ? it->second.get() : nullptr;
+}
+
+void TransformFeedbackManager::RemoveTransformFeedback(GLuint client_id) {
+  if (client_id) {
+    transform_feedbacks_.erase(client_id);
+  }
+}
+
+void TransformFeedbackManager::RemoveBoundBuffer(Buffer* buffer) {
+  for (auto iter = transform_feedbacks_.begin();
+       iter != transform_feedbacks_.end(); ++iter) {
+    iter->second->RemoveBoundBuffer(buffer);
+  }
+}
+
+}  // namespace gles2
+}  // namespace gpu