BackingStoreMac.mm [plain text]
/*
* Copyright (C) 2011 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:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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.
*/
#import "config.h"
#import "BackingStore.h"
#import "CGUtilities.h"
#import "ShareableBitmap.h"
#import "UpdateInfo.h"
#import "WebPageProxy.h"
#import <WebCore/GraphicsContext.h>
#import <WebCore/Region.h>
using namespace WebCore;
namespace WebKit {
void BackingStore::performWithScrolledRectTransform(const IntRect& rect, void (^block)(const IntRect&, const IntSize&))
{
if (m_scrolledRect.isEmpty() || m_scrolledRectOffset.isZero() || !m_scrolledRect.intersects(rect)) {
block(rect, IntSize());
return;
}
// The part of rect that's outside the scrolled rect is not translated.
Region untranslatedRegion = rect;
untranslatedRegion.subtract(m_scrolledRect);
Vector<IntRect> untranslatedRects = untranslatedRegion.rects();
for (size_t i = 0; i < untranslatedRects.size(); ++i)
block(untranslatedRects[i], IntSize());
// The part of rect that intersects the scrolled rect comprises up to four parts, each subject
// to a different translation (all translations are equivalent modulo the dimensions of the
// scrolled rect to the scroll offset).
IntRect intersection = rect;
intersection.intersect(m_scrolledRect);
IntRect scrolledRect = m_scrolledRect;
IntSize offset = m_scrolledRectOffset;
scrolledRect.move(-offset);
IntRect part = intersection;
part.intersect(scrolledRect);
if (!part.isEmpty())
block(part, offset);
part = intersection;
offset += IntSize(0, -m_scrolledRect.height());
scrolledRect.move(IntSize(0, m_scrolledRect.height()));
part.intersect(scrolledRect);
if (!part.isEmpty())
block(part, offset);
part = intersection;
offset += IntSize(-m_scrolledRect.width(), 0);
scrolledRect.move(IntSize(m_scrolledRect.width(), 0));
part.intersect(scrolledRect);
if (!part.isEmpty())
block(part, offset);
part = intersection;
offset += IntSize(0, m_scrolledRect.height());
scrolledRect.move(IntSize(0, -m_scrolledRect.height()));
part.intersect(scrolledRect);
if (!part.isEmpty())
block(part, offset);
}
void BackingStore::resetScrolledRect()
{
ASSERT(!m_scrolledRect.isEmpty());
if (m_scrolledRectOffset.isZero()) {
m_scrolledRect = IntRect();
return;
}
IntSize scaledSize = m_scrolledRect.size();
scaledSize.scale(m_deviceScaleFactor);
RetainPtr<CGColorSpaceRef> colorSpace(AdoptCF, CGColorSpaceCreateDeviceRGB());
RetainPtr<CGContextRef> context(AdoptCF, CGBitmapContextCreate(0, scaledSize.width(), scaledSize.height(), 8, scaledSize.width() * 4, colorSpace.get(), kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host));
CGContextScaleCTM(context.get(), m_deviceScaleFactor, m_deviceScaleFactor);
CGContextScaleCTM(context.get(), 1, -1);
CGContextTranslateCTM(context.get(), -m_scrolledRect.x(), -m_scrolledRect.maxY());
paint(context.get(), m_scrolledRect);
IntRect sourceRect(IntPoint(), m_scrolledRect.size());
paintBitmapContext(backingStoreContext(), context.get(), m_deviceScaleFactor, m_scrolledRect.location(), sourceRect);
m_scrolledRect = IntRect();
m_scrolledRectOffset = IntSize();
}
void BackingStore::paint(PlatformGraphicsContext context, const IntRect& rect)
{
// FIXME: This is defined outside the block to work around bugs in llvm-gcc 4.2.
__block CGRect source;
performWithScrolledRectTransform(rect, ^(const IntRect& part, const IntSize& offset) {
if (m_cgLayer) {
CGContextSaveGState(context);
CGContextClipToRect(context, part);
CGContextScaleCTM(context, 1, -1);
CGContextDrawLayerAtPoint(context, CGPointMake(-offset.width(), offset.height() - m_size.height()), m_cgLayer.get());
CGContextRestoreGState(context);
return;
}
ASSERT(m_bitmapContext);
source = part;
source.origin.x += offset.width();
source.origin.y += offset.height();
paintBitmapContext(context, m_bitmapContext.get(), m_deviceScaleFactor, part.location(), source);
});
}
CGContextRef BackingStore::backingStoreContext()
{
if (m_cgLayer)
return CGLayerGetContext(m_cgLayer.get());
// Try to create a layer.
if (CGContextRef containingWindowContext = m_webPageProxy->containingWindowGraphicsContext()) {
m_cgLayer.adoptCF(CGLayerCreateWithContext(containingWindowContext, m_size, 0));
CGContextRef layerContext = CGLayerGetContext(m_cgLayer.get());
CGContextSetBlendMode(layerContext, kCGBlendModeCopy);
// We want the origin to be in the top left corner so flip the backing store context.
CGContextTranslateCTM(layerContext, 0, m_size.height());
CGContextScaleCTM(layerContext, 1, -1);
if (m_bitmapContext) {
// Paint the contents of the bitmap into the layer context.
paintBitmapContext(layerContext, m_bitmapContext.get(), m_deviceScaleFactor, CGPointZero, CGRectMake(0, 0, m_size.width(), m_size.height()));
m_bitmapContext = nullptr;
}
return layerContext;
}
if (!m_bitmapContext) {
RetainPtr<CGColorSpaceRef> colorSpace(AdoptCF, CGColorSpaceCreateDeviceRGB());
IntSize scaledSize(m_size);
scaledSize.scale(m_deviceScaleFactor);
m_bitmapContext.adoptCF(CGBitmapContextCreate(0, scaledSize.width(), scaledSize.height(), 8, scaledSize.width() * 4, colorSpace.get(), kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host));
CGContextSetBlendMode(m_bitmapContext.get(), kCGBlendModeCopy);
CGContextScaleCTM(m_bitmapContext.get(), m_deviceScaleFactor, m_deviceScaleFactor);
// We want the origin to be in the top left corner so flip the backing store context.
CGContextTranslateCTM(m_bitmapContext.get(), 0, m_size.height());
CGContextScaleCTM(m_bitmapContext.get(), 1, -1);
}
return m_bitmapContext.get();
}
void BackingStore::incorporateUpdate(ShareableBitmap* bitmap, const UpdateInfo& updateInfo)
{
CGContextRef context = backingStoreContext();
scroll(updateInfo.scrollRect, updateInfo.scrollOffset);
IntPoint updateRectLocation = updateInfo.updateRectBounds.location();
GraphicsContext ctx(context);
__block GraphicsContext* graphicsContext = &ctx;
// Paint all update rects.
for (size_t i = 0; i < updateInfo.updateRects.size(); ++i) {
IntRect updateRect = updateInfo.updateRects[i];
IntRect srcRect = updateRect;
// FIXME: This is defined outside the block to work around bugs in llvm-gcc 4.2.
__block IntRect srcPart;
performWithScrolledRectTransform(srcRect, ^(const IntRect& part, const IntSize& offset) {
srcPart = part;
srcPart.move(-updateRectLocation.x(), -updateRectLocation.y());
bitmap->paint(*graphicsContext, updateInfo.deviceScaleFactor, part.location() + offset, srcPart);
});
}
}
void BackingStore::scroll(const IntRect& scrollRect, const IntSize& scrollOffset)
{
if (scrollOffset.isZero())
return;
if (!m_scrolledRect.isEmpty() && m_scrolledRect != scrollRect)
resetScrolledRect();
m_scrolledRect = scrollRect;
int width = (m_scrolledRectOffset.width() - scrollOffset.width()) % m_scrolledRect.width();
if (width < 0)
width += m_scrolledRect.width();
m_scrolledRectOffset.setWidth(width);
int height = (m_scrolledRectOffset.height() - scrollOffset.height()) % m_scrolledRect.height();
if (height < 0)
height += m_scrolledRect.height();
m_scrolledRectOffset.setHeight(height);
}
} // namespace WebKit