Use client side arrays for GL_STREAM_DRAW attributes

gpu/command_buffer/service/buffer_manager.cc

 // Copyright (c) 2012 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/buffer_manager.h"
 #include <limits>
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "gpu/command_buffer/common/gles2_cmd_utils.h"
+#include "gpu/command_buffer/service/feature_info.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 #include "gpu/command_buffer/service/memory_tracking.h"
 
 namespace gpu {
 namespace gles2 {
 
-BufferManager::BufferManager(MemoryTracker* memory_tracker)
+BufferManager::BufferManager(
+    MemoryTracker* memory_tracker,
+    FeatureInfo* feature_info)
     : memory_tracker_(
           new MemoryTypeTracker(memory_tracker, MemoryTracker::kManaged)),
+      feature_info_(feature_info),
       allow_buffers_on_multiple_targets_(false),
       buffer_info_count_(0),
       have_context_(true) {
 }
 
 BufferManager::~BufferManager() {
   DCHECK(buffer_infos_.empty());
   CHECK_EQ(buffer_info_count_, 0u);
 }
 
@@ skipping 34 matching lines @@
   --buffer_info_count_;
 }
 
 Buffer::Buffer(BufferManager* manager, GLuint service_id)
     : manager_(manager),
       deleted_(false),
       service_id_(service_id),
       target_(0),
       size_(0),
       usage_(GL_STATIC_DRAW),
-      shadowed_(false) {
+      shadowed_(false),
+      is_client_side_array_(false) {
   manager_->StartTracking(this);
 }
 
 Buffer::~Buffer() {
   if (manager_) {
     if (manager_->have_context_) {
       GLuint id = service_id();
       glDeleteBuffersARB(1, &id);
     }
     manager_->StopTracking(this);
     manager_ = NULL;
   }
 }
 
 void Buffer::SetInfo(
-    GLsizeiptr size, GLenum usage, bool shadow) {
+    GLsizeiptr size, GLenum usage, bool shadow, const GLvoid* data,
+    bool is_client_side_array) {
   usage_ = usage;
+  is_client_side_array_ = is_client_side_array;
   if (size != size_ || shadow != shadowed_) {
     shadowed_ = shadow;
     size_ = size;
     ClearCache();
     if (shadowed_) {
       shadow_.reset(new int8[size]);
-      memset(shadow_.get(), 0, size);
+      if (!data) {
+        memset(shadow_.get(), 0, size);
+      }
+    } else {
+      shadow_.reset();
     }
   }
+  if (shadowed_ && data) {
+    memcpy(shadow_.get(), data, size);
+  }
 }
 
 bool Buffer::CheckRange(
     GLintptr offset, GLsizeiptr size) const {
   int32 end = 0;
   return offset >= 0 && size >= 0 &&
          offset <= std::numeric_limits<int32>::max() &&
          size <= std::numeric_limits<int32>::max() &&
          SafeAddInt32(offset, size, &end) && end <= size_;
 }
@@ skipping 101 matching lines @@
        it != buffer_infos_.end(); ++it) {
     if (it->second->service_id() == service_id) {
       *client_id = it->first;
       return true;
     }
   }
   return false;
 }
 
 void BufferManager::SetInfo(
-    Buffer* info, GLsizeiptr size, GLenum usage) {
+    Buffer* info, GLsizeiptr size, GLenum usage, const GLvoid* data) {
   DCHECK(info);
   memory_tracker_->TrackMemFree(info->size());
-  info->SetInfo(size,
-                usage,
-                info->target() == GL_ELEMENT_ARRAY_BUFFER ||
-                allow_buffers_on_multiple_targets_);
+  bool is_client_side_array =
+      (usage == GL_STREAM_DRAW &&
+       feature_info_->workarounds().use_client_side_arrays_for_stream_buffers);
+  bool shadow = info->target() == GL_ELEMENT_ARRAY_BUFFER ||
+                allow_buffers_on_multiple_targets_ ||
+                is_client_side_array;
+  info->SetInfo(size, usage, shadow, data, is_client_side_array);
   memory_tracker_->TrackMemAlloc(info->size());
 }
 
 bool BufferManager::SetTarget(Buffer* info, GLenum target) {
   // Check that we are not trying to bind it to a different target.
   if (info->target() != 0 && info->target() != target &&
       !allow_buffers_on_multiple_targets_) {
     return false;
   }
   if (info->target() == 0) {
     info->set_target(target);
   }
   return true;
 }
 
 }  // namespace gles2
 }  // namespace gpu