1/* 2 * Copyright (C) 2012 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' 14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS 17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 23 * THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "config.h" 27#include "ScrollingTreeFixedNode.h" 28 29#if ENABLE(ASYNC_SCROLLING) 30 31#include "ScrollingStateFixedNode.h" 32#include "ScrollingTree.h" 33#include <QuartzCore/CALayer.h> 34 35namespace WebCore { 36 37PassRefPtr<ScrollingTreeFixedNode> ScrollingTreeFixedNode::create(ScrollingTree& scrollingTree, ScrollingNodeID nodeID) 38{ 39 return adoptRef(new ScrollingTreeFixedNode(scrollingTree, nodeID)); 40} 41 42ScrollingTreeFixedNode::ScrollingTreeFixedNode(ScrollingTree& scrollingTree, ScrollingNodeID nodeID) 43 : ScrollingTreeNode(scrollingTree, FixedNode, nodeID) 44{ 45 scrollingTree.fixedOrStickyNodeAdded(); 46} 47 48ScrollingTreeFixedNode::~ScrollingTreeFixedNode() 49{ 50 scrollingTree().fixedOrStickyNodeRemoved(); 51} 52 53void ScrollingTreeFixedNode::updateBeforeChildren(const ScrollingStateNode& stateNode) 54{ 55 const ScrollingStateFixedNode& fixedStateNode = toScrollingStateFixedNode(stateNode); 56 57 if (fixedStateNode.hasChangedProperty(ScrollingStateNode::ScrollLayer)) 58 m_layer = fixedStateNode.layer(); 59 60 if (stateNode.hasChangedProperty(ScrollingStateFixedNode::ViewportConstraints)) 61 m_constraints = fixedStateNode.viewportConstraints(); 62} 63 64static inline CGPoint operator*(CGPoint& a, const CGSize& b) 65{ 66 return CGPointMake(a.x * b.width, a.y * b.height); 67} 68 69void ScrollingTreeFixedNode::updateLayersAfterAncestorChange(const ScrollingTreeNode& changedNode, const FloatRect& fixedPositionRect, const FloatSize& cumulativeDelta) 70{ 71 FloatPoint layerPosition = m_constraints.layerPositionForViewportRect(fixedPositionRect); 72 layerPosition -= cumulativeDelta; 73 74 CGRect layerBounds = [m_layer bounds]; 75 CGPoint anchorPoint = [m_layer anchorPoint]; 76 CGPoint newPosition = layerPosition - m_constraints.alignmentOffset() + anchorPoint * layerBounds.size; 77 78 [m_layer setPosition:newPosition]; 79 80 if (!m_children) 81 return; 82 83 FloatSize newDelta = layerPosition - m_constraints.layerPositionAtLastLayout() + cumulativeDelta; 84 85 for (auto& child : *m_children) 86 child->updateLayersAfterAncestorChange(changedNode, fixedPositionRect, newDelta); 87} 88 89} // namespace WebCore 90 91#endif // ENABLE(ASYNC_SCROLLING) 92