third_party/WebKit/Source/core/layout/PaintInvalidationState.cpp

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "config.h"
   6 #include "core/layout/PaintInvalidationState.h"
   7
   8 #include "core/layout/LayoutInline.h"
   9 #include "core/layout/LayoutView.h"
  10 #include "core/layout/svg/LayoutSVGModelObject.h"
  11 #include "core/layout/svg/LayoutSVGRoot.h"
  12 #include "core/paint/DeprecatedPaintLayer.h"
  13
  14 namespace blink {
  15
  16 PaintInvalidationState::PaintInvalidationState(const LayoutView& layoutView, Vector<LayoutObject*>& pendingDelayedPaintInvalidations, PaintInvalidationState* ownerPaintInvalidationState)
  17     : m_clipped(false)
  18     , m_cachedOffsetsEnabled(true)
  19     , m_forcedSubtreeInvalidationWithinContainer(false)
  20     , m_paintInvalidationContainer(*layoutView.containerForPaintInvalidation())
  21     , m_pendingDelayedPaintInvalidations(pendingDelayedPaintInvalidations)
  22 {
  23     bool establishesPaintInvalidationContainer = layoutView == m_paintInvalidationContainer;
  24     if (!establishesPaintInvalidationContainer) {
  25         if ((ownerPaintInvalidationState && !ownerPaintInvalidationState->m_cachedOffsetsEnabled)
  26             || !layoutView.supportsPaintInvalidationStateCachedOffsets()) {
  27             m_cachedOffsetsEnabled = false;
  28             return;
  29         }
  30         if (ownerPaintInvalidationState && ownerPaintInvalidationState->m_forcedSubtreeInvalidationWithinContainer)
  31             m_forcedSubtreeInvalidationWithinContainer = true;
  32         FloatPoint point = layoutView.localToContainerPoint(FloatPoint(), &m_paintInvalidationContainer, TraverseDocumentBoundaries);
  33         m_paintOffset = LayoutSize(point.x(), point.y());
  34     }
  35     m_clipRect = layoutView.viewRect();
  36     m_clipRect.move(m_paintOffset);
  37     m_clipped = true;
  38 }
  39
  40 PaintInvalidationState::PaintInvalidationState(PaintInvalidationState& next, LayoutBoxModelObject& layoutObject, const LayoutBoxModelObject& paintInvalidationContainer)
  41     : m_clipped(false)
  42     , m_cachedOffsetsEnabled(true)
  43     , m_forcedSubtreeInvalidationWithinContainer(next.m_forcedSubtreeInvalidationWithinContainer)
  44     , m_paintInvalidationContainer(paintInvalidationContainer)
  45     , m_pendingDelayedPaintInvalidations(next.pendingDelayedPaintInvalidationTargets())
  46 {
  47     // FIXME: SVG could probably benefit from a stack-based optimization like html does. crbug.com/391054
  48     bool establishesPaintInvalidationContainer = layoutObject == m_paintInvalidationContainer;
  49     bool fixed = layoutObject.style()->position() == FixedPosition;
  50
  51     if (!layoutObject.supportsPaintInvalidationStateCachedOffsets() || !next.m_cachedOffsetsEnabled)
  52         m_cachedOffsetsEnabled = false;
  53     if (establishesPaintInvalidationContainer) {
  54         // When we hit a new paint invalidation container, we don't need to
  55         // continue forcing a check for paint invalidation, since we're
  56         // descending into a different invalidation container. (For instance if
  57         // our parents were moved, the entire container will just move.)
  58         m_forcedSubtreeInvalidationWithinContainer = false;
  59     } else {
  60         if (m_cachedOffsetsEnabled) {
  61             if (fixed) {
  62                 FloatPoint fixedOffset = layoutObject.localToContainerPoint(FloatPoint(), &m_paintInvalidationContainer, TraverseDocumentBoundaries);
  63                 m_paintOffset = LayoutSize(fixedOffset.x(), fixedOffset.y());
  64             } else {
  65                 LayoutSize offset = layoutObject.isBox() && !layoutObject.isTableRow() ? toLayoutBox(layoutObject).locationOffset() : LayoutSize();
  66                 m_paintOffset = next.m_paintOffset + offset;
  67             }
  68
  69             if (layoutObject.isOutOfFlowPositioned() && !fixed) {
  70                 if (LayoutObject* container = layoutObject.container()) {
  71                     if (container->style()->hasInFlowPosition() && container->isLayoutInline())
  72                         m_paintOffset += toLayoutInline(container)->offsetForInFlowPositionedInline(toLayoutBox(layoutObject));
  73                 }
  74             }
  75
  76             if (layoutObject.style()->hasInFlowPosition() && layoutObject.hasLayer())
  77                 m_paintOffset += layoutObject.layer()->offsetForInFlowPosition();
  78         }
  79
  80         m_clipped = !fixed && next.m_clipped;
  81         if (m_clipped)
  82             m_clipRect = next.m_clipRect;
  83     }
  84
  85     if (m_cachedOffsetsEnabled && layoutObject.isSVGRoot()) {
  86         const LayoutSVGRoot& svgRoot = toLayoutSVGRoot(layoutObject);
  87         m_svgTransform = adoptPtr(new AffineTransform(svgRoot.localToBorderBoxTransform()));
  88         if (svgRoot.shouldApplyViewportClip())
  89             addClipRectRelativeToPaintOffset(LayoutSize(svgRoot.pixelSnappedSize()));
  90     }
  91
  92     applyClipIfNeeded(layoutObject);
  93
  94     // FIXME: <http://bugs.webkit.org/show_bug.cgi?id=13443> Apply control clip if present.
  95 }
  96
  97 PaintInvalidationState::PaintInvalidationState(PaintInvalidationState& next, const LayoutSVGModelObject& layoutObject)
  98     : m_clipped(next.m_clipped)
  99     , m_cachedOffsetsEnabled(next.m_cachedOffsetsEnabled)
 100     , m_forcedSubtreeInvalidationWithinContainer(next.m_forcedSubtreeInvalidationWithinContainer)
 101     , m_clipRect(next.m_clipRect)
 102     , m_paintOffset(next.m_paintOffset)
 103     , m_paintInvalidationContainer(next.m_paintInvalidationContainer)
 104     , m_pendingDelayedPaintInvalidations(next.pendingDelayedPaintInvalidationTargets())
 105 {
 106     ASSERT(layoutObject != m_paintInvalidationContainer);
 107
 108     if (m_cachedOffsetsEnabled)
 109         m_svgTransform = adoptPtr(new AffineTransform(next.svgTransform() * layoutObject.localToParentTransform()));
 110 }
 111
 112 void PaintInvalidationState::addClipRectRelativeToPaintOffset(const LayoutSize& clipSize)
 113 {
 114     LayoutRect clipRect(toPoint(m_paintOffset), clipSize);
 115     if (m_clipped) {
 116         m_clipRect.intersect(clipRect);
 117     } else {
 118         m_clipRect = clipRect;
 119         m_clipped = true;
 120     }
 121 }
 122
 123 void PaintInvalidationState::applyClipIfNeeded(const LayoutObject& layoutObject)
 124 {
 125     if (!layoutObject.hasOverflowClip())
 126         return;
 127
 128     const LayoutBox& box = toLayoutBox(layoutObject);
 129
 130     // Do not clip scroll layer contents because the compositor expects the whole layer
 131     // to be always invalidated in-time.
 132     if (box.usesCompositedScrolling())
 133         ASSERT(!m_clipped); // The box should establish paint invalidation container, so no m_clipped inherited.
 134     else
 135         addClipRectRelativeToPaintOffset(LayoutSize(box.layer()->size()));
 136
 137     m_paintOffset -= box.scrolledContentOffset();
 138 }
 139
 140 } // namespace blink