Fix border radius on composited children.

third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp

 // Copyright 2014 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/paint/PaintLayerPainter.h"
 
 #include "core/frame/LocalFrame.h"
 #include "core/layout/LayoutView.h"
 #include "core/paint/ClipPathClipper.h"
 #include "core/paint/FilterPainter.h"
@@ skipping 233 matching lines @@
       paintLayer.previousScrollOffsetAccumulationForPainting()) {
     needsRepaint = true;
     shouldClearEmptyPaintPhaseFlags = true;
   }
   paintLayer.setPreviousScrollOffsetAccumulationForPainting(
       paintingInfo.scrollOffsetAccumulation);
 
   return needsRepaint;
 }
 
+void adjustOffsetForAncestorClippingMask(

[chrishtr, 2016/12/07 19:16:24]

This is now dead code.

+    const PaintLayer& childLayer,
+    const PaintLayer& ancestorLayer,
+    LayoutPoint& offset)
+{
+    // Adjust the offset to reflect the fact that the fragment is
+    // positioned for the clipping container object.
+    LayoutPoint childOffsetToAncestor;
+    childLayer.convertToLayerCoords(&ancestorLayer, childOffsetToAncestor);
+    offset.move(
+        LayoutSize(-childOffsetToAncestor.x(), -childOffsetToAncestor.y()));
+}
+
 PaintResult PaintLayerPainter::paintLayerContents(
     GraphicsContext& context,
     const PaintLayerPaintingInfo& paintingInfoArg,
     PaintLayerFlags paintFlags,
     FragmentPolicy fragmentPolicy) {
   Optional<ScopedPaintChunkProperties> scopedPaintChunkProperties;
   if (RuntimeEnabledFeatures::slimmingPaintV2Enabled() &&
       RuntimeEnabledFeatures::rootLayerScrollingEnabled() &&
       m_paintLayer.layoutObject() &&
       m_paintLayer.layoutObject()->isLayoutView()) {
@@ skipping 103 matching lines @@
   // These helpers output clip and compositing operations using a RAII pattern.
   // Stack-allocated-varibles are destructed in the reverse order of
   // construction, so they are nested properly.
   Optional<ClipPathClipper> clipPathClipper;
   // Clip-path, like border radius, must not be applied to the contents of a
   // composited-scrolling container.  It must, however, still be applied to the
   // mask layer, so that the compositor can properly mask the
   // scrolling contents and scrollbars.
   if (m_paintLayer.layoutObject()->hasClipPath() &&
       (!m_paintLayer.needsCompositedScrolling() ||
-       (paintFlags & PaintLayerPaintingChildClippingMaskPhase))) {
+       (paintFlags & (PaintLayerPaintingChildClippingMaskPhase |
+                      PaintLayerPaintingAncestorClippingMaskPhase)))) {
     paintingInfo.ancestorHasClipPathClipping = true;
 
     LayoutRect referenceBox(m_paintLayer.boxForClipPath());
     // Note that this isn't going to work correctly if crossing a column
     // boundary. The reference box should be determined per-fragment, and hence
     // this ought to be performed after fragmentation.
     if (m_paintLayer.enclosingPaginationLayer())
       m_paintLayer.convertFromFlowThreadToVisualBoundingBoxInAncestor(
           paintingInfo.rootLayer, referenceBox);
     else
@@ skipping 35 matching lines @@
   if (shouldPaintContent || shouldPaintSelfOutline ||
       isPaintingOverlayScrollbars) {
     // Collect the fragments. This will compute the clip rectangles and paint
     // offsets for each layer fragment.
     ClipRectsCacheSlot cacheSlot = (paintFlags & PaintLayerUncachedClipRects)
                                        ? UncachedClipRects
                                        : PaintingClipRects;
     // TODO(trchen): We haven't decided how to handle visual fragmentation with
     // SPv2.  Related thread
     // https://groups.google.com/a/chromium.org/forum/#!topic/graphics-dev/81XuWFf-mxM
+    LayoutPoint offsetToClipper;
+    PaintLayer* paintLayerForFragments = &m_paintLayer;
+    if (paintFlags & PaintLayerPaintingAncestorClippingMaskPhase) {
+      // Compute fragments and their clips with respect to the clipping
+      // container. The paint rect is in this layer's space, so convert it
+      // to the clipper's layer's space. The rootLayer is also changed to
+      // the clipper's layer to simplify coordinate system adjustments.
+      paintLayerForFragments = m_paintLayer.clippingContainer()->enclosingLayer();
+      localPaintingInfo.rootLayer = paintLayerForFragments;
+      m_paintLayer.convertToLayerCoords(localPaintingInfo.rootLayer, offsetToClipper);
+      localPaintingInfo.paintDirtyRect.moveBy(offsetToClipper);
+    }
+
     if (fragmentPolicy == ForceSingleFragment ||
-        RuntimeEnabledFeatures::slimmingPaintV2Enabled())
-      m_paintLayer.appendSingleFragmentIgnoringPagination(
+        RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
+      paintLayerForFragments->appendSingleFragmentIgnoringPagination(
           layerFragments, localPaintingInfo.rootLayer,
           localPaintingInfo.paintDirtyRect, cacheSlot,
-          IgnoreOverlayScrollbarSize, respectOverflowClip, &offsetFromRoot,
-          localPaintingInfo.subPixelAccumulation);
-    else
-      m_paintLayer.collectFragments(layerFragments, localPaintingInfo.rootLayer,
-                                    localPaintingInfo.paintDirtyRect, cacheSlot,
-                                    IgnoreOverlayScrollbarSize,
-                                    respectOverflowClip, &offsetFromRoot,
-                                    localPaintingInfo.subPixelAccumulation);
+          IgnoreOverlayScrollbarSize, respectOverflowClip,
+          &offsetFromRoot, localPaintingInfo.subPixelAccumulation);
+    } else {
+      paintLayerForFragments->collectFragments(
+          layerFragments, localPaintingInfo.rootLayer,
+          localPaintingInfo.paintDirtyRect, cacheSlot,
+          IgnoreOverlayScrollbarSize, respectOverflowClip,
+          &offsetFromRoot, localPaintingInfo.subPixelAccumulation);
+    }
+
+    if (paintFlags & PaintLayerPaintingAncestorClippingMaskPhase) {
+      // Fragment offsets have been computed in the clipping container's
+      // layer's coordinate system, but for the rest of painting we need
+      // them in the layer coordinate. So move them and the foreground rect
+      // that is also in the clipper's space.
+      LayoutSize negativeOffset(-offsetToClipper.x(), -offsetToClipper.y());
+      for (auto& fragment: layerFragments) {
+        fragment.foregroundRect.move(negativeOffset);
+        fragment.paginationOffset.move(negativeOffset);
+      }
+    }
 
     if (shouldPaintContent) {
       // TODO(wangxianzhu): This is for old slow scrolling. Implement similar
       // optimization for slimming paint v2.
       shouldPaintContent = atLeastOneFragmentIntersectsDamageRect(
           layerFragments, localPaintingInfo, paintFlags, offsetFromRoot);
       if (!shouldPaintContent)
         result = MayBeClippedByPaintDirtyRect;
     }
   }
@@ skipping 83 matching lines @@
     if (shouldPaintOverlayScrollbars)
       paintOverflowControlsForFragments(layerFragments, context,
                                         localPaintingInfo, paintFlags);
   }  // FilterPainter block
 
   bool shouldPaintMask =
       (paintFlags & PaintLayerPaintingCompositingMaskPhase) &&
       shouldPaintContent && m_paintLayer.layoutObject()->hasMask() &&
       !selectionOnly;
   bool shouldPaintClippingMask =
-      (paintFlags & PaintLayerPaintingChildClippingMaskPhase) &&
+      (paintFlags & (PaintLayerPaintingChildClippingMaskPhase |
+                     PaintLayerPaintingAncestorClippingMaskPhase)) &&
       shouldPaintContent && !selectionOnly;
 
   if (shouldPaintMask)
     paintMaskForFragments(layerFragments, context, localPaintingInfo,
                           paintFlags);
   if (shouldPaintClippingMask) {
     // Paint the border radius mask for the fragments.
     paintChildClippingMaskForFragments(layerFragments, context,
                                        localPaintingInfo, paintFlags);
   }
@@ skipping 58 matching lines @@
   // its parent.
   PaintLayer* parentLayer = m_paintLayer.parent();
 
   LayoutObject* object = m_paintLayer.layoutObject();
   LayoutView* view = object->view();
   bool isFixedPosObjectInPagedMedia =
       object->style()->position() == FixedPosition &&
       object->container() == view && view->pageLogicalHeight();
   PaintLayer* paginationLayer = m_paintLayer.enclosingPaginationLayer();
   PaintLayerFragments fragments;
+
   // TODO(crbug.com/619094): Figure out the correct behaviour for fixed position
   // objects in paged media with vertical writing modes.
   if (isFixedPosObjectInPagedMedia && view->isHorizontalWritingMode()) {
     // "For paged media, boxes with fixed positions are repeated on every page."
     // https://www.w3.org/TR/2011/REC-CSS2-20110607/visuren.html#fixed-positioning
     unsigned pages =
         ceilf(view->documentRect().height() / view->pageLogicalHeight());
     LayoutPoint paginationOffset;
 
     // The fixed position object is offset from the top of the page, so remove
@@ skipping 76 matching lines @@
       if (needsToClip(paintingInfo, clipRectForFragment)) {
         if (m_paintLayer.layoutObject()->isPositioned() &&
             clipRectForFragment.isClippedByClipCss())
           UseCounter::count(m_paintLayer.layoutObject()->document(),
                             UseCounter::ClipCssOfPositionedElement);
         if (m_paintLayer.layoutObject()->isFixedPositioned())
           UseCounter::count(m_paintLayer.layoutObject()->document(),
                             UseCounter::ClipCssOfFixedPositionElement);
         clipRecorder.emplace(context, *parentLayer->layoutObject(),
                              DisplayItem::kClipLayerParent, clipRectForFragment,
-                             &paintingInfo, fragment.paginationOffset,
+                             paintingInfo.rootLayer, fragment.paginationOffset,
                              paintFlags);
       }
     }
     if (paintFragmentByApplyingTransform(context, paintingInfo, paintFlags,
                                          fragment.paginationOffset) ==
         MayBeClippedByPaintDirtyRect)
       result = MayBeClippedByPaintDirtyRect;
   }
   return result;
 }
@@ skipping 117 matching lines @@
 
   for (auto& fragment : layerFragments) {
     // We need to apply the same clips and transforms that
     // paintFragmentWithPhase would have.
     LayoutRect cullRect = fragment.backgroundRect.rect();
 
     Optional<LayerClipRecorder> clipRecorder;
     if (needsToClip(localPaintingInfo, fragment.backgroundRect)) {
       clipRecorder.emplace(context, *m_paintLayer.layoutObject(),
                            DisplayItem::kClipLayerOverflowControls,
-                           fragment.backgroundRect, &localPaintingInfo,
+                           fragment.backgroundRect,
+                           localPaintingInfo.rootLayer,
                            fragment.paginationOffset, paintFlags);
     }
 
     Optional<ScrollRecorder> scrollRecorder;
     if (!RuntimeEnabledFeatures::slimmingPaintV2Enabled() &&
         !localPaintingInfo.scrollOffsetAccumulation.isZero()) {
       cullRect.move(localPaintingInfo.scrollOffsetAccumulation);
       scrollRecorder.emplace(context, *m_paintLayer.layoutObject(),
                              DisplayItem::kScrollOverflowControls,
                              localPaintingInfo.scrollOffsetAccumulation);
@@ skipping 30 matching lines @@
       case PaintPhaseSelfOutlineOnly:
       case PaintPhaseMask:  // Mask painting will handle clipping to self.
         clippingRule = LayerClipRecorder::DoNotIncludeSelfForBorderRadius;
         break;
       default:
         clippingRule = LayerClipRecorder::IncludeSelfForBorderRadius;
         break;
     }
 
     clipRecorder.emplace(context, *m_paintLayer.layoutObject(), clipType,
-                         clipRect, &paintingInfo, fragment.paginationOffset,
-                         paintFlags, clippingRule);
+                         clipRect, paintingInfo.rootLayer,
+                         fragment.paginationOffset, paintFlags, clippingRule);
   }
 
   LayoutRect newCullRect(clipRect.rect());
   Optional<ScrollRecorder> scrollRecorder;
   LayoutPoint paintOffset = -m_paintLayer.layoutBoxLocation();
   if (RuntimeEnabledFeatures::slimmingPaintV2Enabled()) {
     const auto* objectPaintProperties =
         m_paintLayer.layoutObject()->paintProperties();
     DCHECK(objectPaintProperties &&
            objectPaintProperties->localBorderBoxProperties());
@@ skipping 51 matching lines @@
   // Optimize clipping for the single fragment case.
   bool shouldClip = localPaintingInfo.clipToDirtyRect &&
                     layerFragments.size() == 1 &&
                     !layerFragments[0].foregroundRect.isEmpty();
   ClipState clipState = HasNotClipped;
   Optional<LayerClipRecorder> clipRecorder;
   if (shouldClip &&
       needsToClip(localPaintingInfo, layerFragments[0].foregroundRect)) {
     clipRecorder.emplace(context, *m_paintLayer.layoutObject(),
                          DisplayItem::kClipLayerForeground,
-                         layerFragments[0].foregroundRect, &localPaintingInfo,
+                         layerFragments[0].foregroundRect,
+                         localPaintingInfo.rootLayer,
                          layerFragments[0].paginationOffset, paintFlags);
     clipState = HasClipped;
   }
 
   // We have to loop through every fragment multiple times, since we have to
   // issue paint invalidations in each specific phase in order for interleaving
   // of the fragments to work properly.
   if (selectionOnly) {
     paintForegroundForFragmentsWithPhase(PaintPhaseSelection, layerFragments,
                                          context, localPaintingInfo, paintFlags,
@@ skipping 126 matching lines @@
 
   PaintLayerPaintingInfo paintingInfo(&m_paintLayer,
                                       LayoutRect(enclosingIntRect(damageRect)),
                                       paintFlags, LayoutSize());
   paintLayer(context, paintingInfo, PaintLayerPaintingOverlayScrollbars);
 
   m_paintLayer.setContainsDirtyOverlayScrollbars(false);
 }
 
 }  // namespace blink