KCanvasMaskerQuartz.mm [plain text]
/*
* Copyright (C) 2005, 2006 Alexander Kellett <lypanov@kde.org>
*
* 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 COMPUTER, INC. ``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 COMPUTER, INC. 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.
*/
#include "config.h"
#if SVG_SUPPORT
#import "KCanvasMaskerQuartz.h"
#import "SVGRenderStyle.h"
#import "KCanvasResourcesQuartz.h"
#import "KRenderingDeviceQuartz.h"
#import "QuartzSupport.h"
#import <QuartzCore/CoreImage.h>
namespace WebCore {
static CIImage *applyLuminanceToAlphaFilter(CIImage *inputImage)
{
CIFilter *luminanceToAlpha = [CIFilter filterWithName:@"CIColorMatrix"];
[luminanceToAlpha setDefaults];
CGFloat alpha[4] = {0.2125, 0.7154, 0.0721, 0};
CGFloat zero[4] = {0, 0, 0, 0};
[luminanceToAlpha setValue:inputImage forKey:@"inputImage"];
[luminanceToAlpha setValue:[CIVector vectorWithValues:zero count:4] forKey:@"inputRVector"];
[luminanceToAlpha setValue:[CIVector vectorWithValues:zero count:4] forKey:@"inputGVector"];
[luminanceToAlpha setValue:[CIVector vectorWithValues:zero count:4] forKey:@"inputBVector"];
[luminanceToAlpha setValue:[CIVector vectorWithValues:alpha count:4] forKey:@"inputAVector"];
[luminanceToAlpha setValue:[CIVector vectorWithValues:zero count:4] forKey:@"inputBiasVector"];
return [luminanceToAlpha valueForKey:@"outputImage"];
}
static CIImage *applyExpandAlphatoGrayscaleFilter(CIImage *inputImage)
{
CIFilter *alphaToGrayscale = [CIFilter filterWithName:@"CIColorMatrix"];
CGFloat zero[4] = {0, 0, 0, 0};
[alphaToGrayscale setDefaults];
[alphaToGrayscale setValue:inputImage forKey:@"inputImage"];
[alphaToGrayscale setValue:[CIVector vectorWithValues:zero count:4] forKey:@"inputRVector"];
[alphaToGrayscale setValue:[CIVector vectorWithValues:zero count:4] forKey:@"inputGVector"];
[alphaToGrayscale setValue:[CIVector vectorWithValues:zero count:4] forKey:@"inputBVector"];
[alphaToGrayscale setValue:[CIVector vectorWithX:0.0 Y:0.0 Z:0.0 W:1.0] forKey:@"inputAVector"];
[alphaToGrayscale setValue:[CIVector vectorWithX:1.0 Y:1.0 Z:1.0 W:0.0] forKey:@"inputBiasVector"];
return [alphaToGrayscale valueForKey:@"outputImage"];
}
static CIImage *transformImageIntoGrayscaleMask(CIImage *inputImage)
{
CIFilter *blackBackground = [CIFilter filterWithName:@"CIConstantColorGenerator"];
[blackBackground setValue:[CIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:1.0] forKey:@"inputColor"];
CIFilter *layerOverBlack = [CIFilter filterWithName:@"CISourceOverCompositing"];
[layerOverBlack setValue:[blackBackground valueForKey:@"outputImage"] forKey:@"inputBackgroundImage"];
[layerOverBlack setValue:inputImage forKey:@"inputImage"];
CIImage *luminanceAlpha = applyLuminanceToAlphaFilter([layerOverBlack valueForKey:@"outputImage"]);
CIImage *luminanceAsGrayscale = applyExpandAlphatoGrayscaleFilter(luminanceAlpha);
CIImage *alphaAsGrayscale = applyExpandAlphatoGrayscaleFilter(inputImage);
CIFilter *multipliedGrayscale = [CIFilter filterWithName:@"CIMultiplyCompositing"];
[multipliedGrayscale setValue:luminanceAsGrayscale forKey:@"inputBackgroundImage"];
[multipliedGrayscale setValue:alphaAsGrayscale forKey:@"inputImage"];
return [multipliedGrayscale valueForKey:@"outputImage"];
}
void KCanvasMaskerQuartz::applyMask(const FloatRect& boundingBox) const
{
if (!m_mask)
return;
// Create grayscale bitmap context
int width = m_mask->size().width();
int height = m_mask->size().height();
void *imageBuffer = fastMalloc(width * height);
CGColorSpaceRef grayColorSpace = CGColorSpaceCreateDeviceGray();
CGContextRef grayscaleContext = CGBitmapContextCreate(imageBuffer, width, height, 8, width, grayColorSpace, kCGImageAlphaNone);
CGColorSpaceRelease(grayColorSpace);
CIContext *ciGrayscaleContext = [CIContext contextWithCGContext:grayscaleContext options:nil];
KCanvasImageQuartz *maskImage = static_cast<KCanvasImageQuartz *>(m_mask);
CIImage *grayscaleMask = transformImageIntoGrayscaleMask([CIImage imageWithCGLayer:maskImage->cgLayer()]);
[ciGrayscaleContext drawImage:grayscaleMask atPoint:CGPointZero fromRect:CGRectMake(0, 0, width, height)];
CGImageRef grayscaleImage = CGBitmapContextCreateImage(grayscaleContext);
CGContextRef cgContext = static_cast<KRenderingDeviceQuartz*>(renderingDevice())->currentCGContext();
CGContextClipToMask(cgContext, CGRectMake(0, 0, width, height), grayscaleImage);
CGImageRelease(grayscaleImage);
CGContextRelease(grayscaleContext);
fastFree(imageBuffer);
}
}
#endif // SVG_SUPPORT