src/third_party/WebKit/Source/platform/graphics/filters/SkiaImageFilterBuilder.cpp

   1 /*
   2  * Copyright (C) 2012 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  15  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  17  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  20  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  21  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25 #include "config.h"
  26
  27 #include "platform/graphics/filters/SkiaImageFilterBuilder.h"
  28
  29 #include "SkBlurImageFilter.h"
  30 #include "SkColorFilterImageFilter.h"
  31 #include "SkColorMatrixFilter.h"
  32 #include "SkDropShadowImageFilter.h"
  33 #include "SkMatrixImageFilter.h"
  34 #include "SkTableColorFilter.h"
  35 #include "platform/graphics/ImageBuffer.h"
  36 #include "platform/graphics/filters/FilterEffect.h"
  37 #include "platform/graphics/filters/FilterOperations.h"
  38 #include "platform/graphics/filters/SourceGraphic.h"
  39 #include "public/platform/WebPoint.h"
  40
  41 namespace WebCore {
  42
  43 SkiaImageFilterBuilder::SkiaImageFilterBuilder()
  44     : m_context(0)
  45 {
  46 }
  47
  48 SkiaImageFilterBuilder::SkiaImageFilterBuilder(GraphicsContext* context)
  49     : m_context(context)
  50 {
  51 }
  52
  53 SkiaImageFilterBuilder::~SkiaImageFilterBuilder()
  54 {
  55 }
  56
  57 PassRefPtr<SkImageFilter> SkiaImageFilterBuilder::build(FilterEffect* effect, ColorSpace colorSpace, bool destinationRequiresValidPreMultipliedPixels)
  58 {
  59     if (!effect)
  60         return nullptr;
  61
  62     bool requiresPMColorValidation = effect->mayProduceInvalidPreMultipliedPixels() && destinationRequiresValidPreMultipliedPixels;
  63
  64     if (SkImageFilter* filter = effect->getImageFilter(colorSpace, requiresPMColorValidation))
  65         return filter;
  66
  67     // Note that we may still need the color transform even if the filter is null
  68     RefPtr<SkImageFilter> origFilter = requiresPMColorValidation ? effect->createImageFilter(this) : effect->createImageFilterWithoutValidation(this);
  69     RefPtr<SkImageFilter> filter = transformColorSpace(origFilter.get(), effect->operatingColorSpace(), colorSpace);
  70     effect->setImageFilter(colorSpace, requiresPMColorValidation, filter.get());
  71     if (filter.get() != origFilter.get())
  72         effect->setImageFilter(effect->operatingColorSpace(), requiresPMColorValidation, origFilter.get());
  73     return filter.release();
  74 }
  75
  76 PassRefPtr<SkImageFilter> SkiaImageFilterBuilder::transformColorSpace(
  77     SkImageFilter* input, ColorSpace srcColorSpace, ColorSpace dstColorSpace) {
  78
  79     RefPtr<SkColorFilter> colorFilter = ImageBuffer::createColorSpaceFilter(srcColorSpace, dstColorSpace);
  80     if (!colorFilter)
  81         return input;
  82
  83     return adoptRef(SkColorFilterImageFilter::Create(colorFilter.get(), input));
  84 }
  85
  86 bool SkiaImageFilterBuilder::buildFilterOperations(const FilterOperations& operations, blink::WebFilterOperations* filters)
  87 {
  88     if (!filters)
  89         return false;
  90
  91     ColorSpace currentColorSpace = ColorSpaceDeviceRGB;
  92     SkImageFilter* const nullFilter = 0;
  93
  94     for (size_t i = 0; i < operations.size(); ++i) {
  95         const FilterOperation& op = *operations.at(i);
  96         switch (op.type()) {
  97         case FilterOperation::REFERENCE: {
  98             RefPtr<SkImageFilter> filter;
  99             ReferenceFilter* referenceFilter = toReferenceFilterOperation(op).filter();
 100             if (referenceFilter && referenceFilter->lastEffect()) {
 101                 FilterEffect* filterEffect = referenceFilter->lastEffect();
 102                 // Prepopulate SourceGraphic with two image filters: one with a null image
 103                 // filter, and the other with a colorspace conversion filter.
 104                 // We don't know what color space the interior nodes will request, so we have to
 105                 // initialize SourceGraphic with both options.
 106                 // Since we know SourceGraphic is always PM-valid, we also use
 107                 // these for the PM-validated options.
 108                 RefPtr<SkImageFilter> deviceFilter = transformColorSpace(nullFilter, currentColorSpace, ColorSpaceDeviceRGB);
 109                 RefPtr<SkImageFilter> linearFilter = transformColorSpace(nullFilter, currentColorSpace, ColorSpaceLinearRGB);
 110                 FilterEffect* sourceGraphic = referenceFilter->sourceGraphic();
 111                 sourceGraphic->setImageFilter(ColorSpaceDeviceRGB, false, deviceFilter.get());
 112                 sourceGraphic->setImageFilter(ColorSpaceLinearRGB, false, linearFilter.get());
 113                 sourceGraphic->setImageFilter(ColorSpaceDeviceRGB, true, deviceFilter.get());
 114                 sourceGraphic->setImageFilter(ColorSpaceLinearRGB, true, linearFilter.get());
 115
 116                 currentColorSpace = filterEffect->operatingColorSpace();
 117                 filter = SkiaImageFilterBuilder::build(filterEffect, currentColorSpace);
 118                 filters->appendReferenceFilter(filter.get());
 119             }
 120             break;
 121         }
 122         case FilterOperation::GRAYSCALE:
 123         case FilterOperation::SEPIA:
 124         case FilterOperation::SATURATE:
 125         case FilterOperation::HUE_ROTATE: {
 126             float amount = toBasicColorMatrixFilterOperation(op).amount();
 127             switch (op.type()) {
 128             case FilterOperation::GRAYSCALE:
 129                 filters->appendGrayscaleFilter(amount);
 130                 break;
 131             case FilterOperation::SEPIA:
 132                 filters->appendSepiaFilter(amount);
 133                 break;
 134             case FilterOperation::SATURATE:
 135                 filters->appendSaturateFilter(amount);
 136                 break;
 137             case FilterOperation::HUE_ROTATE:
 138                 filters->appendHueRotateFilter(amount);
 139                 break;
 140             default:
 141                 ASSERT_NOT_REACHED();
 142             }
 143             break;
 144         }
 145         case FilterOperation::INVERT:
 146         case FilterOperation::OPACITY:
 147         case FilterOperation::BRIGHTNESS:
 148         case FilterOperation::CONTRAST: {
 149             float amount = toBasicComponentTransferFilterOperation(op).amount();
 150             switch (op.type()) {
 151             case FilterOperation::INVERT:
 152                 filters->appendInvertFilter(amount);
 153                 break;
 154             case FilterOperation::OPACITY:
 155                 filters->appendOpacityFilter(amount);
 156                 break;
 157             case FilterOperation::BRIGHTNESS:
 158                 filters->appendBrightnessFilter(amount);
 159                 break;
 160             case FilterOperation::CONTRAST:
 161                 filters->appendContrastFilter(amount);
 162                 break;
 163             default:
 164                 ASSERT_NOT_REACHED();
 165             }
 166             break;
 167         }
 168         case FilterOperation::BLUR: {
 169             float pixelRadius = toBlurFilterOperation(op).stdDeviation().getFloatValue();
 170             filters->appendBlurFilter(pixelRadius);
 171             break;
 172         }
 173         case FilterOperation::DROP_SHADOW: {
 174             const DropShadowFilterOperation& drop = toDropShadowFilterOperation(op);
 175             filters->appendDropShadowFilter(blink::WebPoint(drop.x(), drop.y()), drop.stdDeviation(), drop.color().rgb());
 176             break;
 177         }
 178         case FilterOperation::NONE:
 179             break;
 180         }
 181     }
 182     if (currentColorSpace != ColorSpaceDeviceRGB) {
 183         // Transform to device color space at the end of processing, if required
 184         RefPtr<SkImageFilter> filter = transformColorSpace(nullFilter, currentColorSpace, ColorSpaceDeviceRGB);
 185         filters->appendReferenceFilter(filter.get());
 186     }
 187     return true;
 188 }
 189
 190 PassRefPtr<SkImageFilter> SkiaImageFilterBuilder::buildTransform(const AffineTransform& transform, SkImageFilter* input)
 191 {
 192     return adoptRef(SkMatrixImageFilter::Create(affineTransformToSkMatrix(transform), SkPaint::kHigh_FilterLevel, input));
 193 }
 194
 195 };