1 files changed, 97 insertions, 0 deletions
diff --git a/Source/WebCore/page/scrolling/ScrollingStateNode.cpp b/Source/WebCore/page/scrolling/ScrollingStateNode.cpp
new file mode 100644
index 000000000..8c1a3836b
--- /dev/null
+++ b/Source/WebCore/page/scrolling/ScrollingStateNode.cpp
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2012 Apple 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"
+#include "ScrollingStateNode.h"
+
+#include "ScrollingStateTree.h"
+
+#if ENABLE(THREADED_SCROLLING)
+
+namespace WebCore {
+
+ScrollingStateNode::ScrollingStateNode(ScrollingStateTree* scrollingStateTree, ScrollingNodeID nodeID)
+    : m_scrollingStateTree(scrollingStateTree)
+    , m_nodeID(nodeID)
+    , m_parent(0)
+    , m_scrollLayerDidChange(false)
+{
+}
+
+// This copy constructor is used for cloning nodes in the tree, and it doesn't make sense
+// to clone the relationship pointers, so don't copy that information from the original
+// node.
+ScrollingStateNode::ScrollingStateNode(ScrollingStateNode* stateNode)
+    : m_scrollingStateTree(0)
+    , m_nodeID(stateNode->scrollingNodeID())
+    , m_parent(0)
+    , m_scrollLayerDidChange(stateNode->scrollLayerDidChange())
+{
+    setScrollLayer(stateNode->platformScrollLayer());
+}
+
+ScrollingStateNode::~ScrollingStateNode()
+{
+}
+
+void ScrollingStateNode::cloneAndResetChildNodes(ScrollingStateNode* clone)
+{
+    if (!m_children)
+        return;
+
+    size_t size = m_children->size();
+    for (size_t i = 0; i < size; ++i)
+        clone->appendChild(m_children->at(i)->cloneAndResetNode());
+}
+
+void ScrollingStateNode::appendChild(PassOwnPtr<ScrollingStateNode> childNode)
+{
+    childNode->setParent(this);
+
+    if (!m_children)
+        m_children = adoptPtr(new Vector<OwnPtr<ScrollingStateNode> >);
+
+    m_children->append(childNode);
+}
+
+void ScrollingStateNode::removeChild(ScrollingStateNode* node)
+{
+    if (!m_children)
+        return;
+
+    if (size_t index = m_children->find(node)) {
+        m_scrollingStateTree->didRemoveNode(node->scrollingNodeID());
+        m_children->remove(index);
+        return;
+    }
+
+    size_t size = m_children->size();
+    for (size_t i = 0; i < size; ++i)
+        m_children->at(i)->removeChild(node);
+}
+
+} // namespace WebCore
+
+#endif // ENABLE(THREADED_SCROLLING)