Make sure we call glBufferData on the same data we store internally.

gpu/command_buffer/service/buffer_manager.h

 // 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.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_BUFFER_MANAGER_H_
 #define GPU_COMMAND_BUFFER_SERVICE_BUFFER_MANAGER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <map>
+#include <vector>
+
 #include "base/containers/hash_tables.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "gpu/command_buffer/common/buffer.h"
 #include "gpu/command_buffer/service/gl_utils.h"
 #include "gpu/command_buffer/service/memory_tracking.h"
 #include "gpu/gpu_export.h"
 
@@ skipping 115 matching lines @@
   GLenum initial_target() const {
     return initial_target_;
   }
 
   void set_initial_target(GLenum target) {
     DCHECK_EQ(0u, initial_target_);
     initial_target_ = target;
   }
 
   bool shadowed() const {
-    return shadowed_;
+    return !shadow_.empty();
   }
 
   void MarkAsDeleted() {
     deleted_ = true;
   }
 
+  // Setup the shadow buffer. This will either initialize the shadow buffer
+  // with the passed data or clear the shadow buffer if no shadow required. This
+  // will return a pointer to the shadowed data if using shadow, otherwise will
+  // return the original data pointer.
+  const GLvoid* StageShadow(bool use_shadow, GLsizeiptr size,
+                            const GLvoid* data);
+
   // Sets the size, usage and initial data of a buffer.
   // If shadow is true then if data is NULL buffer will be initialized to 0.
   void SetInfo(
-      GLsizeiptr size, GLenum usage, bool shadow, const GLvoid* data,
-      bool is_client_side_array);
+      GLsizeiptr size, GLenum usage, bool shadow, bool is_client_side_array);
 
   // Sets a range of data for this buffer. Returns false if the offset or size
   // is out of range.
   bool SetRange(
     GLintptr offset, GLsizeiptr size, const GLvoid * data);
 
   // Clears any cache of index ranges.
   void ClearCache();
 
   // Check if an offset, size range is valid for the current buffer.
   bool CheckRange(GLintptr offset, GLsizeiptr size) const;
 
   // The manager that owns this Buffer.
   BufferManager* manager_;
 
-  // A copy of the data in the buffer. This data is only kept if the target
-  // is backed_ = true.
-  scoped_ptr<int8_t[]> shadow_;
+  // A copy of the data in the buffer. This data is only kept if the conditions
+  // checked in UseShadowBuffer() are true.
+  std::vector<uint8_t> shadow_;
 
   // Size of buffer.
   GLsizeiptr size_;
 
   // True if deleted.
   bool deleted_;
 
-  // Whether or not the data is shadowed.
-  bool shadowed_;
-
   // Whether or not this Buffer is not uploaded to the GPU but just
   // sitting in local memory.
   bool is_client_side_array_;
 
   // Service side buffer id.
   GLuint service_id_;
 
   // The first target of buffer. 0 = unset.
   // It is set the first time bindBuffer() is called and cannot be changed.
   GLenum initial_target_;
@@ skipping 107 matching lines @@
   // Does a glBufferData and updates the approprate accounting. Currently
   // Assumes the values have already been validated.
   void DoBufferData(
       ErrorState* error_state,
       Buffer* buffer,
       GLenum target,
       GLsizeiptr size,
       GLenum usage,
       const GLvoid* data);
 
+  // Tests whether a shadow buffer needs to be used.
+  bool UseShadowBuffer(GLenum target, GLenum usage);
+
   // Sets the size, usage and initial data of a buffer.
   // If data is NULL buffer will be initialized to 0 if shadowed.
   void SetInfo(Buffer* buffer, GLenum target, GLsizeiptr size, GLenum usage,
-               const GLvoid* data);
+               bool use_shadow);
 
   scoped_ptr<MemoryTypeTracker> memory_type_tracker_;
   MemoryTracker* memory_tracker_;
   scoped_refptr<FeatureInfo> feature_info_;
 
   // Info for each buffer in the system.
   typedef base::hash_map<GLuint, scoped_refptr<Buffer> > BufferMap;
   BufferMap buffers_;
 
   // Whether or not buffers can be bound to multiple targets.
@@ skipping 11 matching lines @@
   bool have_context_;
   bool use_client_side_arrays_for_stream_buffers_;
 
   DISALLOW_COPY_AND_ASSIGN(BufferManager);
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_BUFFER_MANAGER_H_