Implement CSSOM Smooth Scroll API

Source/core/rendering/RenderLayerScrollableArea.cpp

Index: Source/core/rendering/RenderLayerScrollableArea.cpp
diff --git a/Source/core/rendering/RenderLayerScrollableArea.cpp b/Source/core/rendering/RenderLayerScrollableArea.cpp
index ec64730d6dcc59174e89a37116f63c6143d1631d..c3cb85c70cae888718de9b0732dd61f7c73ee78e 100644
--- a/Source/core/rendering/RenderLayerScrollableArea.cpp
+++ b/Source/core/rendering/RenderLayerScrollableArea.cpp
@@ -53,6 +53,7 @@
 #include "core/page/FocusController.h"
 #include "core/frame/Frame.h"
 #include "core/frame/FrameView.h"
+#include "core/frame/Settings.h"
 #include "core/page/Page.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
 #include "core/rendering/CompositedLayerMapping.h"
@@ -111,6 +112,7 @@ RenderLayerScrollableArea::~RenderLayerScrollableArea()
     if (Frame* frame = m_box->frame()) {
         if (FrameView* frameView = frame->view()) {
             frameView->removeScrollableArea(this);

[Ian Vollick, 2014/02/06 16:02:31]

Can't we just removeAnimationScrollableArea from removeScrollableArea?

+            frameView->removeAnimatingScrollableArea(this);
         }
     }
 
@@ -510,6 +512,39 @@ int RenderLayerScrollableArea::pageStep(ScrollbarOrientation orientation) const
     return max(pageStep, 1);
 }
 
+bool RenderLayerScrollableArea::registerForAnimation()
+{
+    if (Frame* frame = m_box->frame()) {
+        if (FrameView* frameView = frame->view())
+            return frameView->addAnimatingScrollableArea(this);
+    }
+    return false;
+}
+
+void RenderLayerScrollableArea::deregisterForAnimation()
+{
+    if (Frame* frame = m_box->frame()) {
+        if (FrameView* frameView = frame->view())
+            frameView->removeAnimatingScrollableArea(this);
+    }
+}
+
+bool RenderLayerScrollableArea::scheduleAnimation()
+{
+    if (Frame* frame = m_box->frame()) {
+        if (FrameView* frameView = frame->view())
+            return frameView->scheduleAnimation();
+    }
+    return false;
+}
+
+bool RenderLayerScrollableArea::compositedScrollAnimationsEnabled() const
+{
+    if (Settings* settings = m_box->document().settings())
+        return settings->compositorDrivenScrollAnimationsEnabled();
+    return false;
+}
+
 RenderLayer* RenderLayerScrollableArea::layer() const
 {
     return m_box->layer();
@@ -541,11 +576,18 @@ void RenderLayerScrollableArea::computeScrollDimensions()
     setScrollOrigin(IntPoint(-scrollableLeftOverflow, -scrollableTopOverflow));
 }
 
-void RenderLayerScrollableArea::scrollToOffset(const IntSize& scrollOffset, ScrollOffsetClamping clamp)
+void RenderLayerScrollableArea::scrollToOffset(const IntSize& scrollOffset, ScrollOffsetClamping clamp, ScrollBehavior scrollBehavior)
 {
+    cancelProgrammaticScrollAnimation();
     IntSize newScrollOffset = clamp == ScrollOffsetClamped ? clampScrollOffset(scrollOffset) : scrollOffset;
-    if (newScrollOffset != adjustedScrollOffset())
-        scrollToOffsetWithoutAnimation(-scrollOrigin() + newScrollOffset);
+    if (scrollBehavior == ScrollBehaviorAuto)
+        scrollBehavior = m_box->style()->scrollBehavior();
+    if (newScrollOffset != adjustedScrollOffset()) {
+        if (scrollBehavior == ScrollBehaviorSmooth)
+            programmaticallyScrollSmoothlyToOffset(-scrollOrigin() + newScrollOffset);
+        else
+            scrollToOffsetWithoutAnimation(-scrollOrigin() + newScrollOffset);
+    }
 }
 
 void RenderLayerScrollableArea::updateAfterLayout()
@@ -1332,6 +1374,7 @@ void RenderLayerScrollableArea::resize(const PlatformEvent& evt, const LayoutSiz
 
 LayoutRect RenderLayerScrollableArea::exposeRect(const LayoutRect& rect, const ScrollAlignment& alignX, const ScrollAlignment& alignY)
 {
+    cancelProgrammaticScrollAnimation();
     LayoutRect localExposeRect(m_box->absoluteToLocalQuad(FloatQuad(FloatRect(rect)), UseTransforms).boundingBox());
     LayoutRect layerBounds(0, 0, m_box->clientWidth(), m_box->clientHeight());
     LayoutRect r = ScrollAlignment::getRectToExpose(layerBounds, localExposeRect, alignX, alignY);