1 files changed, 26 insertions, 3 deletions
diff --git a/Source/WebKit2/UIProcess/BackingStore.cpp b/Source/WebKit2/UIProcess/BackingStore.cpp
index 06d66af..b468b6b 100644
--- a/Source/WebKit2/UIProcess/BackingStore.cpp
+++ b/Source/WebKit2/UIProcess/BackingStore.cpp
@@ -25,6 +25,9 @@
 
 #include "BackingStore.h"
 
+#include "ShareableBitmap.h"
+#include "UpdateInfo.h"
+
 using namespace WebCore;
 
 #if !PLATFORM(MAC)
@@ -33,13 +36,15 @@ using namespace WebCore;
 
 namespace WebKit {
 
-PassOwnPtr<BackingStore> BackingStore::create(const IntSize& size)
+PassOwnPtr<BackingStore> BackingStore::create(const IntSize& size, WebPageProxy* webPageProxy)
 {
-    return adoptPtr(new BackingStore(size));
+    return adoptPtr(new BackingStore(size, webPageProxy));
 }
 
-BackingStore::BackingStore(const IntSize& size)
+BackingStore::BackingStore(const IntSize& size, WebPageProxy* webPageProxy)
     : m_size(size)
+    , m_webPageProxy(webPageProxy)
+    , m_latestUpdateTimestamp(0)
 {
     ASSERT(!m_size.isEmpty());
 }
@@ -48,4 +53,22 @@ BackingStore::~BackingStore()
 {
 }
 
+void BackingStore::incorporateUpdate(const UpdateInfo& updateInfo)
+{
+    if (updateInfo.timestamp < m_latestUpdateTimestamp) {
+        // The update is too old, discard it.
+        return;
+    }
+
+    ASSERT(m_size == updateInfo.viewSize);
+    
+    RefPtr<ShareableBitmap> bitmap = ShareableBitmap::create(updateInfo.updateRectBounds.size(), updateInfo.bitmapHandle);
+    if (!bitmap)
+        return;
+    
+    incorporateUpdate(bitmap.get(), updateInfo);
+
+    m_latestUpdateTimestamp = updateInfo.timestamp;
+}
+
 } // namespace WebKit