cc/scrollbar_layer.cc - chromium/src - Git at Google

 // Copyright 2012 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 "config.h"

 #include "cc/scrollbar_layer.h"

 #include "CCLayerTreeHost.h"
 #include "CCScrollbarLayerImpl.h"
 #include "CCTextureUpdateQueue.h"
 #include "TraceEvent.h"
 #include "base/basictypes.h"
 #include "cc/layer_painter.h"
 #include <public/WebRect.h>

 using WebKit::WebRect;

 namespace cc {

 scoped_ptr<CCLayerImpl> ScrollbarLayerChromium::createCCLayerImpl()
 {
     return CCScrollbarLayerImpl::create(id()).PassAs<CCLayerImpl>();
 }

 scoped_refptr<ScrollbarLayerChromium> ScrollbarLayerChromium::create(scoped_ptr<WebKit::WebScrollbar> scrollbar, WebKit::WebScrollbarThemePainter painter, scoped_ptr<WebKit::WebScrollbarThemeGeometry> geometry, int scrollLayerId)
 {
     return make_scoped_refptr(new ScrollbarLayerChromium(scrollbar.Pass(), painter, geometry.Pass(), scrollLayerId));
 }

 ScrollbarLayerChromium::ScrollbarLayerChromium(scoped_ptr<WebKit::WebScrollbar> scrollbar, WebKit::WebScrollbarThemePainter painter, scoped_ptr<WebKit::WebScrollbarThemeGeometry> geometry, int scrollLayerId)
     : m_scrollbar(scrollbar.Pass())
     , m_painter(painter)
     , m_geometry(geometry.Pass())
     , m_scrollLayerId(scrollLayerId)
     , m_textureFormat(GraphicsContext3D::INVALID_ENUM)
 {
 }

 ScrollbarLayerChromium::~ScrollbarLayerChromium()
 {
 }

 void ScrollbarLayerChromium::pushPropertiesTo(CCLayerImpl* layer)
 {
     LayerChromium::pushPropertiesTo(layer);

     CCScrollbarLayerImpl* scrollbarLayer = static_cast<CCScrollbarLayerImpl*>(layer);

     if (!scrollbarLayer->scrollbarGeometry())
         scrollbarLayer->setScrollbarGeometry(CCScrollbarGeometryFixedThumb::create(make_scoped_ptr(m_geometry->clone())));

     scrollbarLayer->setScrollbarData(m_scrollbar.get());

     if (m_backTrack && m_backTrack->texture()->haveBackingTexture())
         scrollbarLayer->setBackTrackResourceId(m_backTrack->texture()->resourceId());
     else
         scrollbarLayer->setBackTrackResourceId(0);

     if (m_foreTrack && m_foreTrack->texture()->haveBackingTexture())
         scrollbarLayer->setForeTrackResourceId(m_foreTrack->texture()->resourceId());
     else
         scrollbarLayer->setForeTrackResourceId(0);

     if (m_thumb && m_thumb->texture()->haveBackingTexture())
         scrollbarLayer->setThumbResourceId(m_thumb->texture()->resourceId());
     else
         scrollbarLayer->setThumbResourceId(0);
 }

 ScrollbarLayerChromium* ScrollbarLayerChromium::toScrollbarLayerChromium()
 {
     return this;
 }

 class ScrollbarBackgroundPainter : public LayerPainterChromium {
 public:
     static scoped_ptr<ScrollbarBackgroundPainter> create(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry, WebKit::WebScrollbar::ScrollbarPart trackPart)
     {
         return make_scoped_ptr(new ScrollbarBackgroundPainter(scrollbar, painter, geometry, trackPart));
     }

     virtual void paint(SkCanvas* skCanvas, const IntRect& contentRect, FloatRect&) OVERRIDE
     {
         WebKit::WebCanvas* canvas = skCanvas;
         // The following is a simplification of ScrollbarThemeComposite::paint.
         WebKit::WebRect contentWebRect(contentRect.x(), contentRect.y(), contentRect.width(), contentRect.height());
         m_painter.paintScrollbarBackground(canvas, contentWebRect);

         if (m_geometry->hasButtons(m_scrollbar)) {
             WebRect backButtonStartPaintRect = m_geometry->backButtonStartRect(m_scrollbar);
             m_painter.paintBackButtonStart(canvas, backButtonStartPaintRect);

             WebRect backButtonEndPaintRect = m_geometry->backButtonEndRect(m_scrollbar);
             m_painter.paintBackButtonEnd(canvas, backButtonEndPaintRect);

             WebRect forwardButtonStartPaintRect = m_geometry->forwardButtonStartRect(m_scrollbar);
             m_painter.paintForwardButtonStart(canvas, forwardButtonStartPaintRect);

             WebRect forwardButtonEndPaintRect = m_geometry->forwardButtonEndRect(m_scrollbar);
             m_painter.paintForwardButtonEnd(canvas, forwardButtonEndPaintRect);
         }

         WebRect trackPaintRect = m_geometry->trackRect(m_scrollbar);
         m_painter.paintTrackBackground(canvas, trackPaintRect);

         bool thumbPresent = m_geometry->hasThumb(m_scrollbar);
         if (thumbPresent) {
             if (m_trackPart == WebKit::WebScrollbar::ForwardTrackPart)
                 m_painter.paintForwardTrackPart(canvas, trackPaintRect);
             else
                 m_painter.paintBackTrackPart(canvas, trackPaintRect);
         }

         m_painter.paintTickmarks(canvas, trackPaintRect);
     }
 private:
     ScrollbarBackgroundPainter(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry, WebKit::WebScrollbar::ScrollbarPart trackPart)
         : m_scrollbar(scrollbar)
         , m_painter(painter)
         , m_geometry(geometry)
         , m_trackPart(trackPart)
     {
     }

     WebKit::WebScrollbar* m_scrollbar;
     WebKit::WebScrollbarThemePainter m_painter;
     WebKit::WebScrollbarThemeGeometry* m_geometry;
     WebKit::WebScrollbar::ScrollbarPart m_trackPart;

     DISALLOW_COPY_AND_ASSIGN(ScrollbarBackgroundPainter);
 };

 bool ScrollbarLayerChromium::needsContentsScale() const
 {
     return true;
 }

 IntSize ScrollbarLayerChromium::contentBounds() const
 {
     return IntSize(lroundf(bounds().width() * contentsScale()), lroundf(bounds().height() * contentsScale()));
 }

 class ScrollbarThumbPainter : public LayerPainterChromium {
 public:
     static scoped_ptr<ScrollbarThumbPainter> create(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry)
     {
         return make_scoped_ptr(new ScrollbarThumbPainter(scrollbar, painter, geometry));
     }

     virtual void paint(SkCanvas* skCanvas, const IntRect& contentRect, FloatRect& opaque) OVERRIDE
     {
         WebKit::WebCanvas* canvas = skCanvas;

         // Consider the thumb to be at the origin when painting.
         WebRect thumbRect = m_geometry->thumbRect(m_scrollbar);
         thumbRect.x = 0;
         thumbRect.y = 0;
         m_painter.paintThumb(canvas, thumbRect);
     }

 private:
     ScrollbarThumbPainter(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry)
         : m_scrollbar(scrollbar)
         , m_painter(painter)
         , m_geometry(geometry)
     {
     }

     WebKit::WebScrollbar* m_scrollbar;
     WebKit::WebScrollbarThemePainter m_painter;
     WebKit::WebScrollbarThemeGeometry* m_geometry;

     DISALLOW_COPY_AND_ASSIGN(ScrollbarThumbPainter);
 };

 void ScrollbarLayerChromium::setLayerTreeHost(CCLayerTreeHost* host)
 {
     if (!host || host != layerTreeHost()) {
         m_backTrackUpdater = NULL;
         m_backTrack.reset();
         m_thumbUpdater = NULL;
         m_thumb.reset();
     }

     LayerChromium::setLayerTreeHost(host);
 }

 void ScrollbarLayerChromium::createTextureUpdaterIfNeeded()
 {
     m_textureFormat = layerTreeHost()->rendererCapabilities().bestTextureFormat;

     if (!m_backTrackUpdater)
         m_backTrackUpdater = CachingBitmapCanvasLayerTextureUpdater::Create(ScrollbarBackgroundPainter::create(m_scrollbar.get(), m_painter, m_geometry.get(), WebKit::WebScrollbar::BackTrackPart).PassAs<LayerPainterChromium>());
     if (!m_backTrack)
         m_backTrack = m_backTrackUpdater->createTexture(layerTreeHost()->contentsTextureManager());

     // Only create two-part track if we think the two parts could be different in appearance.
     if (m_scrollbar->isCustomScrollbar()) {
         if (!m_foreTrackUpdater)
             m_foreTrackUpdater = CachingBitmapCanvasLayerTextureUpdater::Create(ScrollbarBackgroundPainter::create(m_scrollbar.get(), m_painter, m_geometry.get(), WebKit::WebScrollbar::ForwardTrackPart).PassAs<LayerPainterChromium>());
         if (!m_foreTrack)
             m_foreTrack = m_foreTrackUpdater->createTexture(layerTreeHost()->contentsTextureManager());
     }

     if (!m_thumbUpdater)
         m_thumbUpdater = CachingBitmapCanvasLayerTextureUpdater::Create(ScrollbarThumbPainter::create(m_scrollbar.get(), m_painter, m_geometry.get()).PassAs<LayerPainterChromium>());
     if (!m_thumb)
         m_thumb = m_thumbUpdater->createTexture(layerTreeHost()->contentsTextureManager());
 }

 void ScrollbarLayerChromium::updatePart(CachingBitmapCanvasLayerTextureUpdater* painter, LayerTextureUpdater::Texture* texture, const IntRect& rect, CCTextureUpdateQueue& queue, CCRenderingStats& stats)
 {
     // Skip painting and uploading if there are no invalidations and
     // we already have valid texture data.
     if (texture->texture()->haveBackingTexture()
             && texture->texture()->size() == rect.size()
             && m_updateRect.isEmpty())
         return;

     // We should always have enough memory for UI.
     ASSERT(texture->texture()->canAcquireBackingTexture());
     if (!texture->texture()->canAcquireBackingTexture())
         return;

     // Paint and upload the entire part.
     float widthScale = static_cast<float>(contentBounds().width()) / bounds().width();
     float heightScale = static_cast<float>(contentBounds().height()) / bounds().height();
     IntRect paintedOpaqueRect;
     painter->prepareToUpdate(rect, rect.size(), widthScale, heightScale, paintedOpaqueRect, stats);
     if (!painter->pixelsDidChange() && texture->texture()->haveBackingTexture()) {
         TRACE_EVENT_INSTANT0("cc","ScrollbarLayerChromium::updatePart no texture upload needed");
         return;
     }

     IntSize destOffset(0, 0);
     texture->update(queue, rect, destOffset, false, stats);
 }


 void ScrollbarLayerChromium::setTexturePriorities(const CCPriorityCalculator&)
 {
     if (contentBounds().isEmpty())
         return;

     createTextureUpdaterIfNeeded();

     bool drawsToRoot = !renderTarget()->parent();
     if (m_backTrack) {
         m_backTrack->texture()->setDimensions(contentBounds(), m_textureFormat);
         m_backTrack->texture()->setRequestPriority(CCPriorityCalculator::uiPriority(drawsToRoot));
     }
     if (m_foreTrack) {
         m_foreTrack->texture()->setDimensions(contentBounds(), m_textureFormat);
         m_foreTrack->texture()->setRequestPriority(CCPriorityCalculator::uiPriority(drawsToRoot));
     }
     if (m_thumb) {
         IntSize thumbSize = layerRectToContentRect(m_geometry->thumbRect(m_scrollbar.get())).size();
         m_thumb->texture()->setDimensions(thumbSize, m_textureFormat);
         m_thumb->texture()->setRequestPriority(CCPriorityCalculator::uiPriority(drawsToRoot));
     }
 }

 void ScrollbarLayerChromium::update(CCTextureUpdateQueue& queue, const CCOcclusionTracker*, CCRenderingStats& stats)
 {
     if (contentBounds().isEmpty())
         return;

     createTextureUpdaterIfNeeded();

     IntPoint scrollbarOrigin(m_scrollbar->location().x, m_scrollbar->location().y);
     IntRect contentRect = layerRectToContentRect(WebKit::WebRect(scrollbarOrigin.x(), scrollbarOrigin.y(), bounds().width(), bounds().height()));
     updatePart(m_backTrackUpdater.get(), m_backTrack.get(), contentRect, queue, stats);
     if (m_foreTrack && m_foreTrackUpdater)
         updatePart(m_foreTrackUpdater.get(), m_foreTrack.get(), contentRect, queue, stats);

     // Consider the thumb to be at the origin when painting.
     WebKit::WebRect thumbRect = m_geometry->thumbRect(m_scrollbar.get());
     IntRect originThumbRect = layerRectToContentRect(WebKit::WebRect(0, 0, thumbRect.width, thumbRect.height));
     if (!originThumbRect.isEmpty())
         updatePart(m_thumbUpdater.get(), m_thumb.get(), originThumbRect, queue, stats);
 }

 }
	// Copyright 2012 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 "config.h"

	#include "cc/scrollbar_layer.h"

	#include "CCLayerTreeHost.h"
	#include "CCScrollbarLayerImpl.h"
	#include "CCTextureUpdateQueue.h"
	#include "TraceEvent.h"
	#include "base/basictypes.h"
	#include "cc/layer_painter.h"
	#include <public/WebRect.h>

	using WebKit::WebRect;

	namespace cc {

	scoped_ptr<CCLayerImpl> ScrollbarLayerChromium::createCCLayerImpl()
	{
	return CCScrollbarLayerImpl::create(id()).PassAs<CCLayerImpl>();
	}

	scoped_refptr<ScrollbarLayerChromium> ScrollbarLayerChromium::create(scoped_ptr<WebKit::WebScrollbar> scrollbar, WebKit::WebScrollbarThemePainter painter, scoped_ptr<WebKit::WebScrollbarThemeGeometry> geometry, int scrollLayerId)
	{
	return make_scoped_refptr(new ScrollbarLayerChromium(scrollbar.Pass(), painter, geometry.Pass(), scrollLayerId));
	}

	ScrollbarLayerChromium::ScrollbarLayerChromium(scoped_ptr<WebKit::WebScrollbar> scrollbar, WebKit::WebScrollbarThemePainter painter, scoped_ptr<WebKit::WebScrollbarThemeGeometry> geometry, int scrollLayerId)
	: m_scrollbar(scrollbar.Pass())
	, m_painter(painter)
	, m_geometry(geometry.Pass())
	, m_scrollLayerId(scrollLayerId)
	, m_textureFormat(GraphicsContext3D::INVALID_ENUM)
	{
	}

	ScrollbarLayerChromium::~ScrollbarLayerChromium()
	{
	}

	void ScrollbarLayerChromium::pushPropertiesTo(CCLayerImpl* layer)
	{
	LayerChromium::pushPropertiesTo(layer);

	CCScrollbarLayerImpl* scrollbarLayer = static_cast<CCScrollbarLayerImpl*>(layer);

	if (!scrollbarLayer->scrollbarGeometry())
	scrollbarLayer->setScrollbarGeometry(CCScrollbarGeometryFixedThumb::create(make_scoped_ptr(m_geometry->clone())));

	scrollbarLayer->setScrollbarData(m_scrollbar.get());

	if (m_backTrack && m_backTrack->texture()->haveBackingTexture())
	scrollbarLayer->setBackTrackResourceId(m_backTrack->texture()->resourceId());
	else
	scrollbarLayer->setBackTrackResourceId(0);

	if (m_foreTrack && m_foreTrack->texture()->haveBackingTexture())
	scrollbarLayer->setForeTrackResourceId(m_foreTrack->texture()->resourceId());
	else
	scrollbarLayer->setForeTrackResourceId(0);

	if (m_thumb && m_thumb->texture()->haveBackingTexture())
	scrollbarLayer->setThumbResourceId(m_thumb->texture()->resourceId());
	else
	scrollbarLayer->setThumbResourceId(0);
	}

	ScrollbarLayerChromium* ScrollbarLayerChromium::toScrollbarLayerChromium()
	{
	return this;
	}

	class ScrollbarBackgroundPainter : public LayerPainterChromium {
	public:
	static scoped_ptr<ScrollbarBackgroundPainter> create(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry, WebKit::WebScrollbar::ScrollbarPart trackPart)
	{
	return make_scoped_ptr(new ScrollbarBackgroundPainter(scrollbar, painter, geometry, trackPart));
	}

	virtual void paint(SkCanvas* skCanvas, const IntRect& contentRect, FloatRect&) OVERRIDE
	{
	WebKit::WebCanvas* canvas = skCanvas;
	// The following is a simplification of ScrollbarThemeComposite::paint.
	WebKit::WebRect contentWebRect(contentRect.x(), contentRect.y(), contentRect.width(), contentRect.height());
	m_painter.paintScrollbarBackground(canvas, contentWebRect);

	if (m_geometry->hasButtons(m_scrollbar)) {
	WebRect backButtonStartPaintRect = m_geometry->backButtonStartRect(m_scrollbar);
	m_painter.paintBackButtonStart(canvas, backButtonStartPaintRect);

	WebRect backButtonEndPaintRect = m_geometry->backButtonEndRect(m_scrollbar);
	m_painter.paintBackButtonEnd(canvas, backButtonEndPaintRect);

	WebRect forwardButtonStartPaintRect = m_geometry->forwardButtonStartRect(m_scrollbar);
	m_painter.paintForwardButtonStart(canvas, forwardButtonStartPaintRect);

	WebRect forwardButtonEndPaintRect = m_geometry->forwardButtonEndRect(m_scrollbar);
	m_painter.paintForwardButtonEnd(canvas, forwardButtonEndPaintRect);
	}

	WebRect trackPaintRect = m_geometry->trackRect(m_scrollbar);
	m_painter.paintTrackBackground(canvas, trackPaintRect);

	bool thumbPresent = m_geometry->hasThumb(m_scrollbar);
	if (thumbPresent) {
	if (m_trackPart == WebKit::WebScrollbar::ForwardTrackPart)
	m_painter.paintForwardTrackPart(canvas, trackPaintRect);
	else
	m_painter.paintBackTrackPart(canvas, trackPaintRect);
	}

	m_painter.paintTickmarks(canvas, trackPaintRect);
	}
	private:
	ScrollbarBackgroundPainter(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry, WebKit::WebScrollbar::ScrollbarPart trackPart)
	: m_scrollbar(scrollbar)
	, m_painter(painter)
	, m_geometry(geometry)
	, m_trackPart(trackPart)
	{
	}

	WebKit::WebScrollbar* m_scrollbar;
	WebKit::WebScrollbarThemePainter m_painter;
	WebKit::WebScrollbarThemeGeometry* m_geometry;
	WebKit::WebScrollbar::ScrollbarPart m_trackPart;

	DISALLOW_COPY_AND_ASSIGN(ScrollbarBackgroundPainter);
	};

	bool ScrollbarLayerChromium::needsContentsScale() const
	{
	return true;
	}

	IntSize ScrollbarLayerChromium::contentBounds() const
	{
	return IntSize(lroundf(bounds().width() * contentsScale()), lroundf(bounds().height() * contentsScale()));
	}

	class ScrollbarThumbPainter : public LayerPainterChromium {
	public:
	static scoped_ptr<ScrollbarThumbPainter> create(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry)
	{
	return make_scoped_ptr(new ScrollbarThumbPainter(scrollbar, painter, geometry));
	}

	virtual void paint(SkCanvas* skCanvas, const IntRect& contentRect, FloatRect& opaque) OVERRIDE
	{
	WebKit::WebCanvas* canvas = skCanvas;

	// Consider the thumb to be at the origin when painting.
	WebRect thumbRect = m_geometry->thumbRect(m_scrollbar);
	thumbRect.x = 0;
	thumbRect.y = 0;
	m_painter.paintThumb(canvas, thumbRect);
	}

	private:
	ScrollbarThumbPainter(WebKit::WebScrollbar* scrollbar, WebKit::WebScrollbarThemePainter painter, WebKit::WebScrollbarThemeGeometry* geometry)
	: m_scrollbar(scrollbar)
	, m_painter(painter)
	, m_geometry(geometry)
	{
	}

	WebKit::WebScrollbar* m_scrollbar;
	WebKit::WebScrollbarThemePainter m_painter;
	WebKit::WebScrollbarThemeGeometry* m_geometry;

	DISALLOW_COPY_AND_ASSIGN(ScrollbarThumbPainter);
	};

	void ScrollbarLayerChromium::setLayerTreeHost(CCLayerTreeHost* host)
	{
	if (!host \|\| host != layerTreeHost()) {
	m_backTrackUpdater = NULL;
	m_backTrack.reset();
	m_thumbUpdater = NULL;
	m_thumb.reset();
	}

	LayerChromium::setLayerTreeHost(host);
	}

	void ScrollbarLayerChromium::createTextureUpdaterIfNeeded()
	{
	m_textureFormat = layerTreeHost()->rendererCapabilities().bestTextureFormat;

	if (!m_backTrackUpdater)
	m_backTrackUpdater = CachingBitmapCanvasLayerTextureUpdater::Create(ScrollbarBackgroundPainter::create(m_scrollbar.get(), m_painter, m_geometry.get(), WebKit::WebScrollbar::BackTrackPart).PassAs<LayerPainterChromium>());
	if (!m_backTrack)
	m_backTrack = m_backTrackUpdater->createTexture(layerTreeHost()->contentsTextureManager());

	// Only create two-part track if we think the two parts could be different in appearance.
	if (m_scrollbar->isCustomScrollbar()) {
	if (!m_foreTrackUpdater)
	m_foreTrackUpdater = CachingBitmapCanvasLayerTextureUpdater::Create(ScrollbarBackgroundPainter::create(m_scrollbar.get(), m_painter, m_geometry.get(), WebKit::WebScrollbar::ForwardTrackPart).PassAs<LayerPainterChromium>());
	if (!m_foreTrack)
	m_foreTrack = m_foreTrackUpdater->createTexture(layerTreeHost()->contentsTextureManager());
	}

	if (!m_thumbUpdater)
	m_thumbUpdater = CachingBitmapCanvasLayerTextureUpdater::Create(ScrollbarThumbPainter::create(m_scrollbar.get(), m_painter, m_geometry.get()).PassAs<LayerPainterChromium>());
	if (!m_thumb)
	m_thumb = m_thumbUpdater->createTexture(layerTreeHost()->contentsTextureManager());
	}

	void ScrollbarLayerChromium::updatePart(CachingBitmapCanvasLayerTextureUpdater* painter, LayerTextureUpdater::Texture* texture, const IntRect& rect, CCTextureUpdateQueue& queue, CCRenderingStats& stats)
	{
	// Skip painting and uploading if there are no invalidations and
	// we already have valid texture data.
	if (texture->texture()->haveBackingTexture()
	&& texture->texture()->size() == rect.size()
	&& m_updateRect.isEmpty())
	return;

	// We should always have enough memory for UI.
	ASSERT(texture->texture()->canAcquireBackingTexture());
	if (!texture->texture()->canAcquireBackingTexture())
	return;

	// Paint and upload the entire part.
	float widthScale = static_cast<float>(contentBounds().width()) / bounds().width();
	float heightScale = static_cast<float>(contentBounds().height()) / bounds().height();
	IntRect paintedOpaqueRect;
	painter->prepareToUpdate(rect, rect.size(), widthScale, heightScale, paintedOpaqueRect, stats);
	if (!painter->pixelsDidChange() && texture->texture()->haveBackingTexture()) {
	TRACE_EVENT_INSTANT0("cc","ScrollbarLayerChromium::updatePart no texture upload needed");
	return;
	}

	IntSize destOffset(0, 0);
	texture->update(queue, rect, destOffset, false, stats);
	}


	void ScrollbarLayerChromium::setTexturePriorities(const CCPriorityCalculator&)
	{
	if (contentBounds().isEmpty())
	return;

	createTextureUpdaterIfNeeded();

	bool drawsToRoot = !renderTarget()->parent();
	if (m_backTrack) {
	m_backTrack->texture()->setDimensions(contentBounds(), m_textureFormat);
	m_backTrack->texture()->setRequestPriority(CCPriorityCalculator::uiPriority(drawsToRoot));
	}
	if (m_foreTrack) {
	m_foreTrack->texture()->setDimensions(contentBounds(), m_textureFormat);
	m_foreTrack->texture()->setRequestPriority(CCPriorityCalculator::uiPriority(drawsToRoot));
	}
	if (m_thumb) {
	IntSize thumbSize = layerRectToContentRect(m_geometry->thumbRect(m_scrollbar.get())).size();
	m_thumb->texture()->setDimensions(thumbSize, m_textureFormat);
	m_thumb->texture()->setRequestPriority(CCPriorityCalculator::uiPriority(drawsToRoot));
	}
	}

	void ScrollbarLayerChromium::update(CCTextureUpdateQueue& queue, const CCOcclusionTracker*, CCRenderingStats& stats)
	{
	if (contentBounds().isEmpty())
	return;

	createTextureUpdaterIfNeeded();

	IntPoint scrollbarOrigin(m_scrollbar->location().x, m_scrollbar->location().y);
	IntRect contentRect = layerRectToContentRect(WebKit::WebRect(scrollbarOrigin.x(), scrollbarOrigin.y(), bounds().width(), bounds().height()));
	updatePart(m_backTrackUpdater.get(), m_backTrack.get(), contentRect, queue, stats);
	if (m_foreTrack && m_foreTrackUpdater)
	updatePart(m_foreTrackUpdater.get(), m_foreTrack.get(), contentRect, queue, stats);

	// Consider the thumb to be at the origin when painting.
	WebKit::WebRect thumbRect = m_geometry->thumbRect(m_scrollbar.get());
	IntRect originThumbRect = layerRectToContentRect(WebKit::WebRect(0, 0, thumbRect.width, thumbRect.height));
	if (!originThumbRect.isEmpty())
	updatePart(m_thumbUpdater.get(), m_thumb.get(), originThumbRect, queue, stats);
	}

	}