Added an abstract BufferStorage::copyData method and implemented it for…

src/libGLESv2/renderer/BufferStorage.h

@@ -23,6 +23,8 @@ class BufferStorage
     // The data returned is only guaranteed valid until next non-const method.
     virtual void *getData() = 0;
     virtual void setData(const void* data, unsigned int size, unsigned int offset) = 0;
+    virtual void copyData(BufferStorage* sourceStorage, unsigned int size,
+                          unsigned int sourceOffset, unsigned int destOffset) = 0;
     virtual void clear() = 0;
     virtual unsigned int getSize() const = 0;
     virtual bool supportsDirectBinding() const = 0;

src/libGLESv2/renderer/BufferStorage11.cpp

@@ -295,6 +295,26 @@ void BufferStorage11::setData(const void* data, unsigned int size, unsigned int
     mResolvedDataValid = false;
 }
 
+void BufferStorage11::copyData(BufferStorage* sourceStorage, unsigned int size,
+                               unsigned int sourceOffset, unsigned int destOffset)
+{
+    BufferStorage11* source = makeBufferStorage11(sourceStorage);
+    if (source)
+    {
+        ID3D11DeviceContext *context = mRenderer->getDeviceContext();
+
+        D3D11_BOX srcBox;
+        srcBox.left = sourceOffset;
+        srcBox.right = sourceOffset + size;
+        srcBox.top = 0;
+        srcBox.bottom = 1;
+        srcBox.front = 0;
+        srcBox.back = 1;
+
+        context->CopySubresourceRegion(mBuffer, 0, destOffset, 0, 0, source->mBuffer, 0, &srcBox);
+    }
+}
+
 void BufferStorage11::clear()
 {
     mResolvedDataValid = false;

src/libGLESv2/renderer/BufferStorage11.h

@@ -25,6 +25,8 @@ class BufferStorage11 : public BufferStorage
 
     virtual void *getData();
     virtual void setData(const void* data, unsigned int size, unsigned int offset);
+    virtual void copyData(BufferStorage* sourceStorage, unsigned int size,
+                          unsigned int sourceOffset, unsigned int destOffset);
     virtual void clear();
     virtual unsigned int getSize() const;
     virtual bool supportsDirectBinding() const;

src/libGLESv2/renderer/BufferStorage9.cpp

@@ -57,6 +57,19 @@ void BufferStorage9::setData(const void* data, unsigned int size, unsigned int o
     memcpy(reinterpret_cast<char*>(mMemory) + offset, data, size);
 }
 
+void BufferStorage9::copyData(BufferStorage* sourceStorage, unsigned int size,
+                              unsigned int sourceOffset, unsigned int destOffset)
+{
+    BufferStorage9* source = makeBufferStorage9(sourceStorage);
+    if (source)
+    {
+        void* sourceMemory = reinterpret_cast<char*>(source->mMemory) + sourceOffset;
+        void* destMemory = reinterpret_cast<char*>(mMemory) + destOffset;
+
+        memcpy(destMemory, sourceMemory, size);
+    }
+}
+
 void BufferStorage9::clear()
 {
     mSize = 0;

src/libGLESv2/renderer/BufferStorage9.h

@@ -24,6 +24,8 @@ class BufferStorage9 : public BufferStorage
 
     virtual void *getData();
     virtual void setData(const void* data, unsigned int size, unsigned int offset);
+    virtual void copyData(BufferStorage* sourceStorage, unsigned int size,
+                          unsigned int sourceOffset, unsigned int destOffset);
     virtual void clear();
     virtual unsigned int getSize() const;
     virtual bool supportsDirectBinding() const;