gistfile1.diff

diff --git a/Source/WebCore/platform/graphics/TiledBackingStore.cpp b/Source/WebCore/platform/graphics/TiledBackingStore.cpp
index 9bd424c..940b45e 100644
--- a/Source/WebCore/platform/graphics/TiledBackingStore.cpp
+++ b/Source/WebCore/platform/graphics/TiledBackingStore.cpp
@@ -69,10 +69,14 @@ void TiledBackingStore::setTileCreationDelay(double delay)
 void TiledBackingStore::coverWithTilesIfNeeded(const FloatPoint& trajectoryVector)
 {
     IntRect visibleRect = this->visibleRect();
-    if (m_trajectoryVector == trajectoryVector && m_visibleRect == visibleRect)
+
+    FloatPoint normalizedVector = trajectoryVector;
+    normalizedVector.normalize();
+
+    if (m_trajectoryVector == normalizedVector && m_visibleRect == visibleRect)
         return;
 
-    m_trajectoryVector = trajectoryVector;
+    m_trajectoryVector = normalizedVector;
     m_visibleRect = visibleRect;
 
     startBackingStoreUpdateTimer();
@@ -340,8 +344,7 @@ void TiledBackingStore::computeCoverAndKeepRect(const IntRect& visibleRect, IntR
         coverRect.inflateY(visibleRect.height() * (m_coverAreaMultiplier - 1) / 2);
         keepRect = coverRect;
 
-        float trajectoryVectorNorm = sqrt(pow(m_trajectoryVector.x(), 2) + pow(m_trajectoryVector.y(), 2));
-        if (trajectoryVectorNorm) {
+        if (m_trajectoryVector == FloatPoint::zero()) {
             // A null trajectory vector (no motion) means that tiles for the coverArea will be created.
             // A non-null trajectory vector will shrink the covered rect to visibleRect plus its expansion from its
             // center toward the cover area edges in the direction of the given vector.
@@ -356,8 +359,8 @@ void TiledBackingStore::computeCoverAndKeepRect(const IntRect& visibleRect, IntR
 
             // Unite the visible rect with a "ghost" of the visible rect moved in the direction of the trajectory vector.
             coverRect = visibleRect;
-            coverRect.move(coverRect.width() * m_trajectoryVector.x() / trajectoryVectorNorm * trajectoryVectorMultiplier,
-                           coverRect.height() * m_trajectoryVector.y() / trajectoryVectorNorm * trajectoryVectorMultiplier);
+            coverRect.move(coverRect.width() * m_trajectoryVector.x() * trajectoryVectorMultiplier,
+                           coverRect.height() * m_trajectoryVector.y() * trajectoryVectorMultiplier);
 
             coverRect.unite(visibleRect);
         }
diff --git a/Source/WebKit2/UIProcess/API/qt/qquickwebview.cpp b/Source/WebKit2/UIProcess/API/qt/qquickwebview.cpp
index ee1abf4..6391e49 100644
--- a/Source/WebKit2/UIProcess/API/qt/qquickwebview.cpp
+++ b/Source/WebKit2/UIProcess/API/qt/qquickwebview.cpp
@@ -506,7 +506,7 @@ void QQuickWebViewLegacyPrivate::updateViewportSize()
     // The fixed layout is handled by the FrameView and the drawing area doesn't behave differently
     // whether its fixed or not. We still need to tell the drawing area which part of it
     // has to be rendered on tiles, and in desktop mode it's all of it.
-    webPageProxy->drawingArea()->setVisibleContentsRectForScaling(IntRect(IntPoint(), viewportSize), 1);
+    webPageProxy->drawingArea()->setVisibleContentsRect(IntRect(IntPoint(), viewportSize), 1, FloatPoint());
 }
 
 QQuickWebViewFlickablePrivate::QQuickWebViewFlickablePrivate(QQuickWebView* viewport)
@@ -657,7 +657,7 @@ void QQuickWebViewFlickablePrivate::_q_commitScaleChange()
     const QRect visibleRect(visibleContentsRect());
     float scale = pageView->contentsScale();
 
-    drawingArea->setVisibleContentsRectForScaling(visibleRect, scale);
+    drawingArea->setVisibleContentsRect(visibleRect, scale, FloatPoint());
     webPageProxy->setFixedVisibleContentRect(visibleRect);
 }
 
@@ -668,11 +668,9 @@ void QQuickWebViewPrivate::_q_commitPositionChange(const QPointF& trajectoryVect
         return;
 
     const QRect visibleRect(visibleContentsRect());
-    drawingArea->setVisibleContentsRectForPanning(visibleRect, trajectoryVector);
-
-    if (!trajectoryVector.isNull())
-        return;
+    float scale = pageView->contentsScale();
 
+    drawingArea->setVisibleContentsRect(visibleRect, scale, trajectoryVector);
     webPageProxy->setFixedVisibleContentRect(visibleRect);
 }
 
diff --git a/Source/WebKit2/UIProcess/DrawingAreaProxy.h b/Source/WebKit2/UIProcess/DrawingAreaProxy.h
index 8b8dc2b..8f7930c 100644
--- a/Source/WebKit2/UIProcess/DrawingAreaProxy.h
+++ b/Source/WebKit2/UIProcess/DrawingAreaProxy.h
@@ -93,8 +93,7 @@ public:
     virtual void paintToCurrentGLContext(const WebCore::TransformationMatrix&, float, const WebCore::FloatRect&) { }
     virtual void paintLayerTree(BackingStore::PlatformGraphicsContext) { }
     LayerTreeHostProxy* layerTreeHostProxy() const { return m_layerTreeHostProxy.get(); }
-    virtual void setVisibleContentsRectForScaling(const WebCore::IntRect& visibleContentsRect, float scale) { }
-    virtual void setVisibleContentsRectForPanning(const WebCore::IntRect& visibleContentsRect, const WebCore::FloatPoint& trajectoryVector) { }
+    virtual void setVisibleContentsRect(const WebCore::IntRect& visibleContentsRect, float scale, const WebCore::FloatPoint& trajectoryVector) { }
     virtual void createTileForLayer(int layerID, int tileID, const WebKit::UpdateInfo&) { }
     virtual void updateTileForLayer(int layerID, int tileID, const WebKit::UpdateInfo&) { }
     virtual void removeTileForLayer(int layerID, int tileID) { }
diff --git a/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp b/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp
index c0d044b..6edf4ab 100644
--- a/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp
+++ b/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.cpp
@@ -348,16 +348,10 @@ void DrawingAreaProxyImpl::didReceiveLayerTreeHostProxyMessage(CoreIPC::Connecti
         m_layerTreeHostProxy->didReceiveLayerTreeHostProxyMessage(connection, messageID, arguments);
 }
 
-void DrawingAreaProxyImpl::setVisibleContentsRectForScaling(const WebCore::IntRect& visibleContentsRect, float scale)
+void DrawingAreaProxyImpl::setVisibleContentsRect(const WebCore::IntRect& visibleContentsRect, float scale, const WebCore::FloatPoint& trajectoryVector)
 {
     if (m_layerTreeHostProxy)
-        m_layerTreeHostProxy->setVisibleContentsRectForScaling(visibleContentsRect, scale);
-}
-
-void DrawingAreaProxyImpl::setVisibleContentsRectForPanning(const WebCore::IntRect& visibleContentsRect, const WebCore::FloatPoint& trajectoryVector)
-{
-    if (m_layerTreeHostProxy)
-        m_layerTreeHostProxy->setVisibleContentsRectForPanning(visibleContentsRect, trajectoryVector);
+        m_layerTreeHostProxy->setVisibleContentsRect(visibleContentsRect, scale, trajectoryVector);
 }
 
 void DrawingAreaProxyImpl::paintLayerTree(BackingStore::PlatformGraphicsContext context)
diff --git a/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.h b/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.h
index 613073b..2d57417 100644
--- a/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.h
+++ b/Source/WebKit2/UIProcess/DrawingAreaProxyImpl.h
@@ -78,8 +78,7 @@ private:
     bool isInAcceleratedCompositingMode() const { return !m_layerTreeContext.isEmpty(); }
 
 #if USE(UI_SIDE_COMPOSITING)
-    virtual void setVisibleContentsRectForScaling(const WebCore::IntRect& visibleContentsRect, float scale);
-    virtual void setVisibleContentsRectForPanning(const WebCore::IntRect& visibleContentsRect, const WebCore::FloatPoint&);
+    virtual void setVisibleContentsRect(const WebCore::IntRect& visibleContentsRect, float scale, const WebCore::FloatPoint& trajectory);
     virtual void paintToCurrentGLContext(const WebCore::TransformationMatrix&, float opacity, const WebCore::FloatRect&);
     virtual void paintLayerTree(BackingStore::PlatformGraphicsContext);
     void didReceiveLayerTreeHostProxyMessage(CoreIPC::Connection*, CoreIPC::MessageID, CoreIPC::ArgumentDecoder*);
diff --git a/Source/WebKit2/UIProcess/LayerTreeHostProxy.cpp b/Source/WebKit2/UIProcess/LayerTreeHostProxy.cpp
index e760a7d..004c951 100644
--- a/Source/WebKit2/UIProcess/LayerTreeHostProxy.cpp
+++ b/Source/WebKit2/UIProcess/LayerTreeHostProxy.cpp
@@ -118,15 +118,10 @@ void LayerTreeHostProxy::destroyDirectlyCompositedImage(int64_t key)
     dispatchUpdate(bind(&WebLayerTreeRenderer::destroyImage, m_renderer.get(), key));
 }
 
-void LayerTreeHostProxy::setVisibleContentsRectForPanning(const IntRect& rect, const FloatPoint& trajectoryVector)
+void LayerTreeHostProxy::setVisibleContentsRect(const IntRect& rect, float scale, const FloatPoint& trajectoryVector)
 {
-    m_drawingAreaProxy->page()->process()->send(Messages::LayerTreeHost::SetVisibleContentsRectForPanning(rect, trajectoryVector), m_drawingAreaProxy->page()->pageID());
-}
-
-void LayerTreeHostProxy::setVisibleContentsRectForScaling(const IntRect& rect, float scale)
-{
-    m_renderer->setVisibleContentsRectForScaling(rect, scale);
-    m_drawingAreaProxy->page()->process()->send(Messages::LayerTreeHost::SetVisibleContentsRectForScaling(rect, scale), m_drawingAreaProxy->page()->pageID());
+    m_renderer->setVisibleContentsRect(rect, scale);
+    m_drawingAreaProxy->page()->process()->send(Messages::LayerTreeHost::SetVisibleContentsRect(rect, scale, trajectoryVector), m_drawingAreaProxy->page()->pageID());
 }
 
 void LayerTreeHostProxy::renderNextFrame()
diff --git a/Source/WebKit2/UIProcess/LayerTreeHostProxy.h b/Source/WebKit2/UIProcess/LayerTreeHostProxy.h
index f6c31d1..2587c1f 100644
--- a/Source/WebKit2/UIProcess/LayerTreeHostProxy.h
+++ b/Source/WebKit2/UIProcess/LayerTreeHostProxy.h
@@ -54,8 +54,7 @@ public:
     void paintToCurrentGLContext(const WebCore::TransformationMatrix&, float opacity, const WebCore::FloatRect& clip);
     void paintToGraphicsContext(BackingStore::PlatformGraphicsContext);
     void purgeGLResources();
-    void setVisibleContentsRectForScaling(const WebCore::IntRect&, float);
-    void setVisibleContentsRectForPanning(const WebCore::IntRect&, const WebCore::FloatPoint&);
+    void setVisibleContentsRect(const WebCore::IntRect&, float scale, const WebCore::FloatPoint& trajectory);
     void didRenderFrame();
     void createTileForLayer(int layerID, int tileID, const WebKit::UpdateInfo&);
     void updateTileForLayer(int layerID, int tileID, const WebKit::UpdateInfo&);
diff --git a/Source/WebKit2/UIProcess/WebLayerTreeRenderer.cpp b/Source/WebKit2/UIProcess/WebLayerTreeRenderer.cpp
index f2c0495..20229f3 100644
--- a/Source/WebKit2/UIProcess/WebLayerTreeRenderer.cpp
+++ b/Source/WebKit2/UIProcess/WebLayerTreeRenderer.cpp
@@ -155,7 +155,7 @@ void WebLayerTreeRenderer::paintToGraphicsContext(QPainter* painter)
     m_textureMapper->setGraphicsContext(0);
 }
 
-void WebLayerTreeRenderer::setVisibleContentsRectForScaling(const IntRect& rect, float scale)
+void WebLayerTreeRenderer::setVisibleContentsRect(const IntRect& rect, float scale)
 {
     m_visibleContentsRect = rect;
     m_contentsScale = scale;
diff --git a/Source/WebKit2/UIProcess/WebLayerTreeRenderer.h b/Source/WebKit2/UIProcess/WebLayerTreeRenderer.h
index 6c78865..f258489 100644
--- a/Source/WebKit2/UIProcess/WebLayerTreeRenderer.h
+++ b/Source/WebKit2/UIProcess/WebLayerTreeRenderer.h
@@ -51,7 +51,7 @@ public:
     void paintToCurrentGLContext(const WebCore::TransformationMatrix&, float, const WebCore::FloatRect&);
     void paintToGraphicsContext(BackingStore::PlatformGraphicsContext);
     void syncRemoteContent();
-    void setVisibleContentsRectForScaling(const WebCore::IntRect&, float);
+    void setVisibleContentsRect(const WebCore::IntRect&, float scale);
 
     void detach();
     void appendUpdate(const Function<void()>&);
diff --git a/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h b/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h
index 6f336a5..0349e24 100644
--- a/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h
+++ b/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.h
@@ -80,8 +80,7 @@ public:
     virtual void resumeRendering() { }
 
 #if USE(TILED_BACKING_STORE)
-    virtual void setVisibleContentsRectForScaling(const WebCore::IntRect&, float scale) { }
-    virtual void setVisibleContentsRectForPanning(const WebCore::IntRect&, const WebCore::FloatPoint&) { }
+    virtual void setVisibleContentsRect(const WebCore::IntRect&, float scale, const WebCore::FloatPoint&) { }
     virtual void setVisibleContentsRectForLayer(int layerID, const WebCore::IntRect&) { }
     virtual void renderNextFrame() { }
     virtual void purgeBackingStores() { }
diff --git a/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.messages.in b/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.messages.in
index 70fa858..8920de2 100644
--- a/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.messages.in
+++ b/Source/WebKit2/WebProcess/WebPage/LayerTreeHost.messages.in
@@ -20,8 +20,7 @@
 
 #if USE(TILED_BACKING_STORE)
 messages -> LayerTreeHost {
-    SetVisibleContentsRectForPanning(WebCore::IntRect visibleContentsRect, WebCore::FloatPoint trajectoryVectory)
-    SetVisibleContentsRectForScaling(WebCore::IntRect visibleContentsRect, float scale)
+    SetVisibleContentsRect(WebCore::IntRect visibleContentsRect, float scale, WebCore::FloatPoint trajectoryVectory)
     RenderNextFrame()
     PurgeBackingStores()
 }
diff --git a/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.cpp b/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.cpp
index 2137430..468a5e5 100644
--- a/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.cpp
+++ b/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.cpp
@@ -415,24 +415,26 @@ WebCore::IntRect LayerTreeHostQt::visibleContentsRect() const
     return m_visibleContentsRect;
 }
 
-void LayerTreeHostQt::setVisibleContentsRectForScaling(const IntRect& rect, float scale)
+void LayerTreeHostQt::setVisibleContentsRect(const IntRect& rect, float scale, const FloatPoint& trajectoryVector)
 {
-    m_visibleContentsRect = rect;
-    m_contentsScale = scale;
+    bool contentsRectDidChange = rect != m_visibleContentsRect;
+    bool contentsScaleDidChange = scale != m_contentsScale;
 
-    HashSet<WebCore::WebGraphicsLayer*>::iterator end = m_registeredLayers.end();
-    for (HashSet<WebCore::WebGraphicsLayer*>::iterator it = m_registeredLayers.begin(); it != end; ++it) {
-        (*it)->setContentsScale(scale);
-        (*it)->adjustVisibleRect();
-    }
-    scheduleLayerFlush();
-}
+    if (trajectoryVector != FloatPoint::zero())
+        toWebGraphicsLayer(m_nonCompositedContentLayer.get())->setVisibleContentRectTrajectoryVector(trajectoryVector);
 
-void LayerTreeHostQt::setVisibleContentsRectForPanning(const IntRect& rect, const FloatPoint& trajectoryVector)
-{
-    m_visibleContentsRect = rect;
+    if (contentsRectDidChange || contentsScaleDidChange) {
+        m_visibleContentsRect = rect;
+        m_contentsScale = scale;
 
-    toWebGraphicsLayer(m_nonCompositedContentLayer.get())->setVisibleContentRectTrajectoryVector(trajectoryVector);
+        HashSet<WebCore::WebGraphicsLayer*>::iterator end = m_registeredLayers.end();
+        for (HashSet<WebCore::WebGraphicsLayer*>::iterator it = m_registeredLayers.begin(); it != end; ++it) {
+            if (contentsScaleDidChange)
+                (*it)->setContentsScale(scale);
+            if (contentsRectDidChange)
+                (*it)->adjustVisibleRect();
+        }
+    }
 
     scheduleLayerFlush();
 }
diff --git a/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.h b/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.h
index 9db85b7..08f0e64 100644
--- a/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.h
+++ b/Source/WebKit2/WebProcess/WebPage/qt/LayerTreeHostQt.h
@@ -70,8 +70,7 @@ public:
     virtual void renderNextFrame();
     virtual void purgeBackingStores();
     virtual bool layerTreeTileUpdatesAllowed() const;
-    virtual void setVisibleContentsRectForScaling(const WebCore::IntRect&, float scale);
-    virtual void setVisibleContentsRectForPanning(const WebCore::IntRect&, const WebCore::FloatPoint&);
+    virtual void setVisibleContentsRect(const WebCore::IntRect&, float scale, const WebCore::FloatPoint&);
     virtual void didSyncCompositingStateForLayer(const WebLayerInfo&);
     virtual void attachLayer(WebCore::WebGraphicsLayer*);
     virtual void detachLayer(WebCore::WebGraphicsLayer*);