Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(641)

Unified Diff: third_party/WebKit/Source/core/page/scrolling/StickyPositionScrollingConstraints.cpp

Issue 1308273010: Adapt and reland old position sticky implementation (Closed) Base URL: https://chromium.googlesource.com/chromium/blink.git@master
Patch Set: WIP - fix on release, still hits CHECK in LayoutGeometryMap.cpp:156 Created 4 years, 10 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
Index: third_party/WebKit/Source/core/page/scrolling/StickyPositionScrollingConstraints.cpp
diff --git a/third_party/WebKit/Source/core/page/scrolling/StickyPositionScrollingConstraints.cpp b/third_party/WebKit/Source/core/page/scrolling/StickyPositionScrollingConstraints.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..1d4b07ef218ba4e7b677cd9304aaad2da8c9493a
--- /dev/null
+++ b/third_party/WebKit/Source/core/page/scrolling/StickyPositionScrollingConstraints.cpp
@@ -0,0 +1,56 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "core/page/scrolling/StickyPositionScrollingConstraints.h"
+
+namespace blink {
+
+FloatSize StickyPositionScrollingConstraints::computeStickyOffset(const FloatRect& viewportRect) const
+{
+ FloatRect boxRect = m_scrollContainerRelativeStickyBoxRect;
+
+ if (hasAnchorEdge(AnchorEdgeRight)) {
+ float rightLimit = viewportRect.maxX() - m_rightOffset;
+ float rightDelta = std::min<float>(0, rightLimit - m_scrollContainerRelativeStickyBoxRect.maxX());
+ float availableSpace = std::min<float>(0, m_scrollContainerRelativeContainingBlockRect.x() - m_scrollContainerRelativeStickyBoxRect.x());
+ if (rightDelta < availableSpace)
+ rightDelta = availableSpace;
+
+ boxRect.move(rightDelta, 0);
+ }
+
+ if (hasAnchorEdge(AnchorEdgeLeft)) {
+ float leftLimit = viewportRect.x() + m_leftOffset;
+ float leftDelta = std::max<float>(0, leftLimit - m_scrollContainerRelativeStickyBoxRect.x());
+ float availableSpace = std::max<float>(0, m_scrollContainerRelativeContainingBlockRect.maxX() - m_scrollContainerRelativeStickyBoxRect.maxX());
+ if (leftDelta > availableSpace)
+ leftDelta = availableSpace;
+
+ boxRect.move(leftDelta, 0);
+ }
+
+ if (hasAnchorEdge(AnchorEdgeBottom)) {
+ float bottomLimit = viewportRect.maxY() - m_bottomOffset;
+ float bottomDelta = std::min<float>(0, bottomLimit - m_scrollContainerRelativeStickyBoxRect.maxY());
+ float availableSpace = std::min<float>(0, m_scrollContainerRelativeContainingBlockRect.y() - m_scrollContainerRelativeStickyBoxRect.y());
+ if (bottomDelta < availableSpace)
+ bottomDelta = availableSpace;
+
+ boxRect.move(0, bottomDelta);
+ }
+
+ if (hasAnchorEdge(AnchorEdgeTop)) {
+ float topLimit = viewportRect.y() + m_topOffset;
+ float topDelta = std::max<float>(0, topLimit - m_scrollContainerRelativeStickyBoxRect.y());
+ float availableSpace = std::max<float>(0, m_scrollContainerRelativeContainingBlockRect.maxY() - m_scrollContainerRelativeStickyBoxRect.maxY());
+ if (topDelta > availableSpace)
+ topDelta = availableSpace;
+
+ boxRect.move(0, topDelta);
+ }
+
+ return boxRect.location() - m_scrollContainerRelativeStickyBoxRect.location();
+}
+
+} // namespace blink

Powered by Google App Engine
This is Rietveld 408576698