Implementing ACCELERATED_COMPOSITING via Skia

WebCore/platform/graphics/skia/GraphicsLayerSkia.cpp

Index: WebCore/platform/graphics/skia/GraphicsLayerSkia.cpp
===================================================================
--- WebCore/platform/graphics/skia/GraphicsLayerSkia.cpp	(revision 0)
+++ WebCore/platform/graphics/skia/GraphicsLayerSkia.cpp	(revision 0)
@@ -0,0 +1,586 @@
+/*
+ * Copyright (c) 2010, Google Inc. All rights reserved.
+ * Copyright (C) 2009 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:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * 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.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
+ * OWNER OR 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.
+ */
+
+
+/** TODO(Vangelis)
+ * This file borrows code heavily from platform/graphics/win/GraphicsLayerCACF.cpp
+ * (and hence it includes both copyrights)
+ * Ideally the common code (e.g. the code that keeps track of the layer hierarchy
+ * should be kept separate and shared between platforms.
+ */
+
+#include "config.h"
+
+#if USE(ACCELERATED_COMPOSITING)
+
+#include "GraphicsLayerSkia.h"
+
+#include "CString.h"
+#include "FloatConversion.h"
+#include "FloatRect.h"
+#include "Image.h"
+#include "PlatformString.h"
+#include "SystemTime.h"
+#include "LayerSkia.h"
+#include <wtf/CurrentTime.h>
+#include <wtf/StringExtras.h>
+
+using namespace std;
+
+namespace WebCore {
+
+
+static void setLayerBorderColor(LayerSkia* layer, const Color& color)
+{
+    layer->setBorderColor(color);
+}
+
+static void clearBorderColor(LayerSkia* layer)
+{
+    layer->setBorderColor(Color(0, 0, 0, 0));
+}
+
+static void setLayerBackgroundColor(LayerSkia* layer, const Color& color)
+{
+    layer->setBackgroundColor(color);
+}
+
+static void clearLayerBackgroundColor(LayerSkia* layer)
+{
+    layer->setBackgroundColor(0);
+}
+
+GraphicsLayer::CompositingCoordinatesOrientation GraphicsLayer::compositingCoordinatesOrientation()
+{
+    return CompositingCoordinatesBottomUp;
+}
+
+PassOwnPtr<GraphicsLayer> GraphicsLayer::create(GraphicsLayerClient* client)
+{
+    return new GraphicsLayerSkia(client);
+}
+
+GraphicsLayerSkia::GraphicsLayerSkia(GraphicsLayerClient* client)
+    : GraphicsLayer(client)
+    , m_contentsLayerPurpose(NoContentsLayer)
+    , m_contentsLayerHasBackgroundColor(false)
+{
+    m_layer = LayerSkia::create(LayerSkia::Layer, this);
+
+    updateDebugIndicators();
+}
+
+GraphicsLayerSkia::~GraphicsLayerSkia()
+{
+    // clean up the Skia layer
+    if (m_layer)
+        m_layer->removeFromSuperlayer();
+
+    if (m_transformLayer)
+        m_transformLayer->removeFromSuperlayer();
+}
+
+void GraphicsLayerSkia::setName(const String& inName)
+{
+    String name = String::format("GraphicsLayerSkia(%p) GraphicsLayer(%p) ", m_layer.get(), this) + inName;
+    GraphicsLayer::setName(name);
+}
+
+NativeLayer GraphicsLayerSkia::nativeLayer() const
+{
+    return m_layer.get();
+}
+
+bool GraphicsLayerSkia::setChildren(const Vector<GraphicsLayer*>& children)
+{
+    bool childrenChanged = GraphicsLayer::setChildren(children);
+    // FIXME: GraphicsLayer::setChildren calls addChild() for each sublayer, which
+    // will end up calling updateSublayerList() N times.
+    if (childrenChanged)
+        updateSublayerList();
+
+    return childrenChanged;
+}
+
+void GraphicsLayerSkia::addChild(GraphicsLayer* childLayer)
+{
+    GraphicsLayer::addChild(childLayer);
+    updateSublayerList();
+}
+
+void GraphicsLayerSkia::addChildAtIndex(GraphicsLayer* childLayer, int index)
+{
+    GraphicsLayer::addChildAtIndex(childLayer, index);
+    updateSublayerList();
+}
+
+void GraphicsLayerSkia::addChildBelow(GraphicsLayer* childLayer, GraphicsLayer* sibling)
+{
+    GraphicsLayer::addChildBelow(childLayer, sibling);
+    updateSublayerList();
+}
+
+void GraphicsLayerSkia::addChildAbove(GraphicsLayer* childLayer, GraphicsLayer *sibling)
+{
+    GraphicsLayer::addChildAbove(childLayer, sibling);
+    updateSublayerList();
+}
+
+bool GraphicsLayerSkia::replaceChild(GraphicsLayer* oldChild, GraphicsLayer* newChild)
+{
+    if (GraphicsLayer::replaceChild(oldChild, newChild)) {
+        updateSublayerList();
+        return true;
+    }
+    return false;
+}
+
+void GraphicsLayerSkia::removeFromParent()
+{
+    GraphicsLayer::removeFromParent();
+    layerForSuperlayer()->removeFromSuperlayer();
+}
+
+void GraphicsLayerSkia::setPosition(const FloatPoint& point)
+{
+    GraphicsLayer::setPosition(point);
+    updateLayerPosition();
+}
+
+void GraphicsLayerSkia::setAnchorPoint(const FloatPoint3D& point)
+{
+    if (point == m_anchorPoint)
+        return;
+
+    GraphicsLayer::setAnchorPoint(point);
+    updateAnchorPoint();
+}
+
+void GraphicsLayerSkia::setSize(const FloatSize& size)
+{
+    if (size == m_size)
+        return;
+
+    GraphicsLayer::setSize(size);
+    updateLayerSize();
+}
+
+void GraphicsLayerSkia::setTransform(const TransformationMatrix& t)
+{
+    if (t == m_transform)
+        return;
+
+    GraphicsLayer::setTransform(t);
+    updateTransform();
+}
+
+void GraphicsLayerSkia::setChildrenTransform(const TransformationMatrix& t)
+{
+    if (t == m_childrenTransform)
+        return;
+
+    GraphicsLayer::setChildrenTransform(t);
+    updateChildrenTransform();
+}
+
+void GraphicsLayerSkia::setPreserves3D(bool preserves3D)
+{
+    if (preserves3D == m_preserves3D)
+        return;
+
+    GraphicsLayer::setPreserves3D(preserves3D);
+    updateLayerPreserves3D();
+}
+
+void GraphicsLayerSkia::setMasksToBounds(bool masksToBounds)
+{
+    if (masksToBounds == m_masksToBounds)
+        return;
+
+    GraphicsLayer::setMasksToBounds(masksToBounds);
+    updateMasksToBounds();
+}
+
+void GraphicsLayerSkia::setDrawsContent(bool drawsContent)
+{
+    if (drawsContent == m_drawsContent)
+        return;
+
+    GraphicsLayer::setDrawsContent(drawsContent);
+    updateLayerDrawsContent();
+}
+
+void GraphicsLayerSkia::setBackgroundColor(const Color& color)
+{
+    if (m_backgroundColorSet && m_backgroundColor == color)
+        return;
+
+    GraphicsLayer::setBackgroundColor(color);
+
+    m_contentsLayerHasBackgroundColor = true;
+    updateLayerBackgroundColor();
+}
+
+void GraphicsLayerSkia::clearBackgroundColor()
+{
+    if (!m_backgroundColorSet)
+        return;
+
+    GraphicsLayer::clearBackgroundColor();
+    clearLayerBackgroundColor(m_contentsLayer.get());
+}
+
+void GraphicsLayerSkia::setContentsOpaque(bool opaque)
+{
+    if (m_contentsOpaque == opaque)
+        return;
+
+    GraphicsLayer::setContentsOpaque(opaque);
+    updateContentsOpaque();
+}
+
+void GraphicsLayerSkia::setBackfaceVisibility(bool visible)
+{
+    if (m_backfaceVisibility == visible)
+        return;
+
+    GraphicsLayer::setBackfaceVisibility(visible);
+    updateBackfaceVisibility();
+}
+
+void GraphicsLayerSkia::setOpacity(float opacity)
+{
+    float clampedOpacity = max(min(opacity, 1.0f), 0.0f);
+
+    if (m_opacity == clampedOpacity)
+        return;
+
+    GraphicsLayer::setOpacity(clampedOpacity);
+    primaryLayer()->setOpacity(opacity);
+}
+
+void GraphicsLayerSkia::setNeedsDisplay()
+{
+    if (drawsContent())
+        m_layer->setNeedsDisplay();
+}
+
+void GraphicsLayerSkia::setNeedsDisplayInRect(const FloatRect& rect)
+{
+    if (drawsContent())
+        m_layer->setNeedsDisplay(rect);
+}
+
+void GraphicsLayerSkia::setContentsRect(const IntRect& rect)
+{
+    if (rect == m_contentsRect)
+        return;
+
+    GraphicsLayer::setContentsRect(rect);
+    updateContentsRect();
+}
+
+void GraphicsLayerSkia::setContentsToImage(Image* image)
+{
+    // TODO(vangelis): Implement
+}
+
+void GraphicsLayerSkia::setContentsToVideo(PlatformLayer* videoLayer)
+{
+    // TODO(vangelis): Implement
+}
+
+void GraphicsLayerSkia::setGeometryOrientation(CompositingCoordinatesOrientation orientation)
+{
+    if (orientation == m_geometryOrientation)
+        return;
+
+    GraphicsLayer::setGeometryOrientation(orientation);
+    updateGeometryOrientation();
+}
+
+PlatformLayer* GraphicsLayerSkia::hostLayerForSublayers() const
+{
+    return m_transformLayer ? m_transformLayer.get() : m_layer.get();
+}
+
+PlatformLayer* GraphicsLayerSkia::layerForSuperlayer() const
+{
+    return m_transformLayer ? m_transformLayer.get() : m_layer.get();
+}
+
+PlatformLayer* GraphicsLayerSkia::platformLayer() const
+{
+    return primaryLayer();
+}
+
+void GraphicsLayerSkia::setDebugBackgroundColor(const Color& color)
+{
+    if (color.isValid())
+        setLayerBackgroundColor(m_layer.get(), color);
+    else
+        clearLayerBackgroundColor(m_layer.get());
+}
+
+void GraphicsLayerSkia::setDebugBorder(const Color& color, float borderWidth)
+{
+    if (color.isValid()) {
+        setLayerBorderColor(m_layer.get(), color);
+        m_layer->setBorderWidth(borderWidth);
+    } else {
+        clearBorderColor(m_layer.get());
+        m_layer->setBorderWidth(0);
+    }
+}
+
+GraphicsLayer::CompositingCoordinatesOrientation GraphicsLayerSkia::defaultContentsOrientation() const
+{
+    return CompositingCoordinatesTopDown;
+}
+
+void GraphicsLayerSkia::updateSublayerList()
+{
+    Vector<RefPtr<LayerSkia> > newSublayers;
+
+    if (m_transformLayer) {
+        // Add the primary layer first. Even if we have negative z-order children, the primary layer always comes behind.
+        newSublayers.append(m_layer.get());
+    } else if (m_contentsLayer) {
+        // FIXME: add the contents layer in the correct order with negative z-order children.
+        // This does not cause visible rendering issues because currently contents layers are only used
+        // for replaced elements that don't have children.
+        newSublayers.append(m_contentsLayer.get());
+    }
+
+    const Vector<GraphicsLayer*>& childLayers = children();
+    size_t numChildren = childLayers.size();
+    for (size_t i = 0; i < numChildren; ++i) {
+        GraphicsLayerSkia* curChild = static_cast<GraphicsLayerSkia*>(childLayers[i]);
+
+        LayerSkia* childLayer = curChild->layerForSuperlayer();
+        newSublayers.append(childLayer);
+    }
+
+    for (size_t i = 0; i < newSublayers.size(); ++i)
+        newSublayers[i]->removeFromSuperlayer();
+
+    if (m_transformLayer) {
+        m_transformLayer->setSublayers(newSublayers);
+
+        if (m_contentsLayer) {
+            // If we have a transform layer, then the contents layer is parented in the
+            // primary layer (which is itself a child of the transform layer).
+            m_layer->removeAllSublayers();
+            m_layer->addSublayer(m_contentsLayer);
+        }
+    } else
+        m_layer->setSublayers(newSublayers);
+}
+
+void GraphicsLayerSkia::updateLayerPosition()
+{
+    // Position is offset on the layer by the layer anchor point.
+    SkPoint posPoint;
+    posPoint.set(m_position.x() + m_anchorPoint.x() * m_size.width(),
+                 posPoint.fY = m_position.y() + m_anchorPoint.y() * m_size.height());
+
+    primaryLayer()->setPosition(posPoint);
+}
+
+void GraphicsLayerSkia::updateLayerSize()
+{
+    SkIRect rect;
+    rect.set(0, 0, m_size.width(), m_size.height());
+    if (m_transformLayer) {
+        m_transformLayer->setBounds(rect);
+        // The anchor of the contents layer is always at 0.5, 0.5, so the position is center-relative.
+        SkPoint centerPoint;
+        centerPoint.set(m_size.width() / 2.0f, m_size.height() / 2.0f);
+        m_layer->setPosition(centerPoint);
+    }
+
+    m_layer->setBounds(rect);
+
+    // Note that we don't resize m_contentsLayer. It's up the caller to do that.
+
+    // if we've changed the bounds, we need to recalculate the position
+    // of the layer, taking anchor point into account.
+    updateLayerPosition();
+}
+
+void GraphicsLayerSkia::updateAnchorPoint()
+{
+    SkPoint anchorPoint;
+    anchorPoint.set(m_anchorPoint.x(), m_anchorPoint.y());
+    primaryLayer()->setAnchorPoint(anchorPoint);
+    primaryLayer()->setAnchorPointZ(m_anchorPoint.z());
+    updateLayerPosition();
+}
+
+void GraphicsLayerSkia::updateTransform()
+{
+    primaryLayer()->setTransform(m_transform.toAffineTransform());
+}
+
+void GraphicsLayerSkia::updateChildrenTransform()
+{
+    primaryLayer()->setSublayerTransform(m_childrenTransform);
+}
+
+void GraphicsLayerSkia::updateMasksToBounds()
+{
+    m_layer->setMasksToBounds(m_masksToBounds);
+    updateDebugIndicators();
+}
+
+void GraphicsLayerSkia::updateContentsOpaque()
+{
+    m_layer->setOpaque(m_contentsOpaque);
+}
+
+void GraphicsLayerSkia::updateBackfaceVisibility()
+{
+    m_layer->setDoubleSided(m_backfaceVisibility);
+}
+
+void GraphicsLayerSkia::updateLayerPreserves3D()
+{
+    // TODO(vangelis): implement
+}
+
+void GraphicsLayerSkia::updateLayerDrawsContent()
+{
+    if (m_drawsContent)
+        m_layer->setNeedsDisplay();
+
+    updateDebugIndicators();
+}
+
+void GraphicsLayerSkia::updateLayerBackgroundColor()
+{
+    if (!m_contentsLayer)
+        return;
+
+    // We never create the contents layer just for background color yet.
+    if (m_backgroundColorSet)
+        setLayerBackgroundColor(m_contentsLayer.get(), m_backgroundColor);
+    else
+        clearLayerBackgroundColor(m_contentsLayer.get());
+}
+
+void GraphicsLayerSkia::updateContentsImage()
+{
+    // TODO(vangelis): Implement
+}
+
+void GraphicsLayerSkia::updateContentsVideo()
+{
+    // TODO(vangelis): Implement
+}
+
+void GraphicsLayerSkia::updateContentsRect()
+{
+    if (!m_contentsLayer)
+        return;
+
+    SkPoint point;
+    point.set(m_contentsRect.x(), m_contentsRect.y());
+    SkIRect rect;
+    rect.set(0,
+             0,
+             m_contentsRect.width(),
+             m_contentsRect.height());
+
+    m_contentsLayer->setPosition(point);
+    m_contentsLayer->setBounds(rect);
+}
+
+void GraphicsLayerSkia::updateGeometryOrientation()
+{
+    switch (geometryOrientation()) {
+        case CompositingCoordinatesTopDown:
+            m_layer->setGeometryFlipped(false);
+            break;
+
+        case CompositingCoordinatesBottomUp:
+            m_layer->setGeometryFlipped(true);
+            break;
+    }
+    // Geometry orientation is mapped onto children transform in older QuartzCores,
+    // so is handled via setGeometryOrientation().
+}
+
+void GraphicsLayerSkia::setupContentsLayer(LayerSkia* contentsLayer)
+{
+    if (contentsLayer == m_contentsLayer)
+        return;
+
+    if (m_contentsLayer) {
+        m_contentsLayer->removeFromSuperlayer();
+        m_contentsLayer = 0;
+    }
+
+    if (contentsLayer) {
+        m_contentsLayer = contentsLayer;
+
+        if (defaultContentsOrientation() == CompositingCoordinatesBottomUp) {
+            SkPoint anchorPoint;
+            anchorPoint.set(0.0f, 1.0f);
+            m_contentsLayer->setAnchorPoint(anchorPoint);
+        } else {
+            SkPoint anchorPoint;
+            anchorPoint.set(0.0f, 0.0f);
+            m_contentsLayer->setAnchorPoint(anchorPoint);
+        }
+
+        // Insert the content layer first. Video elements require this, because they have
+        // shadow content that must display in front of the video.
+        m_layer->insertSublayer(m_contentsLayer.get(), 0);
+
+        updateContentsRect();
+
+        if (showDebugBorders()) {
+            setLayerBorderColor(m_contentsLayer.get(), Color(0, 0, 128, 180));
+            m_contentsLayer->setBorderWidth(1.0f);
+        }
+    }
+    updateDebugIndicators();
+}
+
+// This function simply mimics the operation of GraphicsLayerCA
+void GraphicsLayerSkia::updateOpacityOnLayer()
+{
+    primaryLayer()->setOpacity(m_opacity);
+}
+
+} // namespace WebCore
+
+#endif // USE(ACCELERATED_COMPOSITING)