Initial import attempt, just to play with. Many things disabled/removed

ui/cc/cc/CCLayerIterator.cpp

Index: ui/cc/cc/CCLayerIterator.cpp
diff --git a/ui/cc/cc/CCLayerIterator.cpp b/ui/cc/cc/CCLayerIterator.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..2d6d2f7f7a9ec054d09091561a0c8b4772a5b30b
--- /dev/null
+++ b/ui/cc/cc/CCLayerIterator.cpp
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2012 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#if USE(ACCELERATED_COMPOSITING)
+
+#include "cc/CCLayerIterator.h"
+
+#include "LayerChromium.h"
+#include "RenderSurfaceChromium.h"
+#include "cc/CCLayerImpl.h"
+#include "cc/CCRenderSurface.h"
+
+namespace WebCore {
+
+template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
+void CCLayerIteratorActions::BackToFront::begin(CCLayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
+{
+    it.m_targetRenderSurfaceLayerIndex = 0;
+    it.m_currentLayerIndex = CCLayerIteratorValue::LayerIndexRepresentingTargetRenderSurface;
+
+    m_highestTargetRenderSurfaceLayer = 0;
+}
+
+template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
+void CCLayerIteratorActions::BackToFront::end(CCLayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
+{
+    it.m_targetRenderSurfaceLayerIndex = CCLayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
+    it.m_currentLayerIndex = 0;
+}
+
+template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
+void CCLayerIteratorActions::BackToFront::next(CCLayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
+{
+    // If the current layer has a RS, move to its layer list. Otherwise, visit the next layer in the current RS layer list.
+    if (it.currentLayerRepresentsContributingRenderSurface()) {
+        // Save our position in the childLayer list for the RenderSurface, then jump to the next RenderSurface. Save where we
+        // came from in the next RenderSurface so we can get back to it.
+        it.targetRenderSurface()->m_currentLayerIndexHistory = it.m_currentLayerIndex;
+        int previousTargetRenderSurfaceLayer = it.m_targetRenderSurfaceLayerIndex;
+
+        it.m_targetRenderSurfaceLayerIndex = ++m_highestTargetRenderSurfaceLayer;
+        it.m_currentLayerIndex = CCLayerIteratorValue::LayerIndexRepresentingTargetRenderSurface;
+
+        it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory = previousTargetRenderSurfaceLayer;
+    } else {
+        ++it.m_currentLayerIndex;
+
+        int targetRenderSurfaceNumChildren = it.targetRenderSurfaceChildren().size();
+        while (it.m_currentLayerIndex == targetRenderSurfaceNumChildren) {
+            // Jump back to the previous RenderSurface, and get back the position where we were in that list, and move to the next position there.
+            if (!it.m_targetRenderSurfaceLayerIndex) {
+                // End of the list
+                it.m_targetRenderSurfaceLayerIndex = CCLayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
+                it.m_currentLayerIndex = 0;
+                return;
+            }
+            it.m_targetRenderSurfaceLayerIndex = it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory;
+            it.m_currentLayerIndex = it.targetRenderSurface()->m_currentLayerIndexHistory + 1;
+
+            targetRenderSurfaceNumChildren = it.targetRenderSurfaceChildren().size();
+        }
+    }
+}
+
+template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
+void CCLayerIteratorActions::FrontToBack::begin(CCLayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
+{
+    it.m_targetRenderSurfaceLayerIndex = 0;
+    it.m_currentLayerIndex = it.targetRenderSurfaceChildren().size() - 1;
+    goToHighestInSubtree(it);
+}
+
+template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
+void CCLayerIteratorActions::FrontToBack::end(CCLayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
+{
+    it.m_targetRenderSurfaceLayerIndex = CCLayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
+    it.m_currentLayerIndex = 0;
+}
+
+template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
+void CCLayerIteratorActions::FrontToBack::next(CCLayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
+{
+    // Moves to the previous layer in the current RS layer list. Then we check if the
+    // new current layer has its own RS, in which case there are things in that RS layer list that are higher, so
+    // we find the highest layer in that subtree.
+    // If we move back past the front of the list, we jump up to the previous RS layer list, picking up again where we
+    // had previously recursed into the current RS layer list.
+
+    if (!it.currentLayerRepresentsTargetRenderSurface()) {
+        // Subtracting one here will eventually cause the current layer to become that layer
+        // representing the target render surface.
+        --it.m_currentLayerIndex;
+        goToHighestInSubtree(it);
+    } else {
+        while (it.currentLayerRepresentsTargetRenderSurface()) {
+            if (!it.m_targetRenderSurfaceLayerIndex) {
+                // End of the list
+                it.m_targetRenderSurfaceLayerIndex = CCLayerIteratorValue::InvalidTargetRenderSurfaceLayerIndex;
+                it.m_currentLayerIndex = 0;
+                return;
+            }
+            it.m_targetRenderSurfaceLayerIndex = it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory;
+            it.m_currentLayerIndex = it.targetRenderSurface()->m_currentLayerIndexHistory;
+        }
+    }
+}
+
+template <typename LayerType, typename LayerList, typename RenderSurfaceType, typename ActionType>
+void CCLayerIteratorActions::FrontToBack::goToHighestInSubtree(CCLayerIterator<LayerType, LayerList, RenderSurfaceType, ActionType>& it)
+{
+    if (it.currentLayerRepresentsTargetRenderSurface())
+        return;
+    while (it.currentLayerRepresentsContributingRenderSurface()) {
+        // Save where we were in the current target surface, move to the next one, and save the target surface that we
+        // came from there so we can go back to it.
+        it.targetRenderSurface()->m_currentLayerIndexHistory = it.m_currentLayerIndex;
+        int previousTargetRenderSurfaceLayer = it.m_targetRenderSurfaceLayerIndex;
+
+        for (LayerType* layer = it.currentLayer(); it.targetRenderSurfaceLayer() != layer; ++it.m_targetRenderSurfaceLayerIndex) { }
+        it.m_currentLayerIndex = it.targetRenderSurfaceChildren().size() - 1;
+
+        it.targetRenderSurface()->m_targetRenderSurfaceLayerIndexHistory = previousTargetRenderSurfaceLayer;
+    }
+}
+
+// Declare each of the above functions for LayerChromium and CCLayerImpl classes so that they are linked.
+template void CCLayerIteratorActions::BackToFront::begin(CCLayerIterator<LayerChromium, Vector<RefPtr<LayerChromium> >, RenderSurfaceChromium, BackToFront> &);
+template void CCLayerIteratorActions::BackToFront::end(CCLayerIterator<LayerChromium, Vector<RefPtr<LayerChromium> >, RenderSurfaceChromium, BackToFront>&);
+template void CCLayerIteratorActions::BackToFront::next(CCLayerIterator<LayerChromium, Vector<RefPtr<LayerChromium> >, RenderSurfaceChromium, BackToFront>&);
+
+template void CCLayerIteratorActions::BackToFront::begin(CCLayerIterator<CCLayerImpl, Vector<CCLayerImpl*>, CCRenderSurface, BackToFront>&);
+template void CCLayerIteratorActions::BackToFront::end(CCLayerIterator<CCLayerImpl, Vector<CCLayerImpl*>, CCRenderSurface, BackToFront>&);
+template void CCLayerIteratorActions::BackToFront::next(CCLayerIterator<CCLayerImpl, Vector<CCLayerImpl*>, CCRenderSurface, BackToFront>&);
+
+template void CCLayerIteratorActions::FrontToBack::next(CCLayerIterator<LayerChromium, Vector<RefPtr<LayerChromium> >, RenderSurfaceChromium, FrontToBack>&);
+template void CCLayerIteratorActions::FrontToBack::end(CCLayerIterator<LayerChromium, Vector<RefPtr<LayerChromium> >, RenderSurfaceChromium, FrontToBack>&);
+template void CCLayerIteratorActions::FrontToBack::begin(CCLayerIterator<LayerChromium, Vector<RefPtr<LayerChromium> >, RenderSurfaceChromium, FrontToBack>&);
+template void CCLayerIteratorActions::FrontToBack::goToHighestInSubtree(CCLayerIterator<LayerChromium, Vector<RefPtr<LayerChromium> >, RenderSurfaceChromium, FrontToBack>&);
+
+template void CCLayerIteratorActions::FrontToBack::next(CCLayerIterator<CCLayerImpl, Vector<CCLayerImpl*>, CCRenderSurface, FrontToBack>&);
+template void CCLayerIteratorActions::FrontToBack::end(CCLayerIterator<CCLayerImpl, Vector<CCLayerImpl*>, CCRenderSurface, FrontToBack>&);
+template void CCLayerIteratorActions::FrontToBack::begin(CCLayerIterator<CCLayerImpl, Vector<CCLayerImpl*>, CCRenderSurface, FrontToBack>&);
+template void CCLayerIteratorActions::FrontToBack::goToHighestInSubtree(CCLayerIterator<CCLayerImpl, Vector<CCLayerImpl*>, CCRenderSurface, FrontToBack>&);
+
+} // namespace WebCore
+
+#endif // USE(ACCELERATED_COMPOSITING)