1 /*
2 * Copyright (C) Research In Motion Limited 2011. All rights reserved.
3 * Copyright (C) 2013 Google Inc. All rights reserved.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public License
16 * along with this library; see the file COPYING.LIB. If not, write to
17 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 */
20
21 #include "config.h"
22 #include "platform/graphics/filters/FEDropShadow.h"
23
24 #include "platform/graphics/GraphicsContext.h"
25 #include "platform/graphics/filters/FEGaussianBlur.h"
26 #include "platform/graphics/filters/SkiaImageFilterBuilder.h"
27 #include "platform/text/TextStream.h"
28 #include "third_party/skia/include/core/SkColorFilter.h"
29 #include "third_party/skia/include/effects/SkBlurImageFilter.h"
30 #include "third_party/skia/include/effects/SkDropShadowImageFilter.h"
31
32 using namespace std;
33
34 namespace WebCore {
35
FEDropShadow(Filter * filter,float stdX,float stdY,float dx,float dy,const Color & shadowColor,float shadowOpacity)36 FEDropShadow::FEDropShadow(Filter* filter, float stdX, float stdY, float dx, float dy, const Color& shadowColor, float shadowOpacity)
37 : FilterEffect(filter)
38 , m_stdX(stdX)
39 , m_stdY(stdY)
40 , m_dx(dx)
41 , m_dy(dy)
42 , m_shadowColor(shadowColor)
43 , m_shadowOpacity(shadowOpacity)
44 {
45 }
46
create(Filter * filter,float stdX,float stdY,float dx,float dy,const Color & shadowColor,float shadowOpacity)47 PassRefPtr<FEDropShadow> FEDropShadow::create(Filter* filter, float stdX, float stdY, float dx, float dy, const Color& shadowColor, float shadowOpacity)
48 {
49 return adoptRef(new FEDropShadow(filter, stdX, stdY, dx, dy, shadowColor, shadowOpacity));
50 }
51
determineAbsolutePaintRect()52 void FEDropShadow::determineAbsolutePaintRect()
53 {
54 Filter* filter = this->filter();
55 ASSERT_UNUSED(filter, filter);
56
57 FloatRect absolutePaintRect = mapRect(inputEffect(0)->absolutePaintRect());
58
59 if (clipsToBounds())
60 absolutePaintRect.intersect(maxEffectRect());
61 else
62 absolutePaintRect.unite(maxEffectRect());
63
64 setAbsolutePaintRect(enclosingIntRect(absolutePaintRect));
65 }
66
mapRect(const FloatRect & rect,bool forward)67 FloatRect FEDropShadow::mapRect(const FloatRect& rect, bool forward)
68 {
69 FloatRect result = rect;
70 Filter* filter = this->filter();
71 ASSERT(filter);
72
73 FloatRect offsetRect = rect;
74 if (forward)
75 offsetRect.move(filter->applyHorizontalScale(m_dx), filter->applyVerticalScale(m_dy));
76 else
77 offsetRect.move(-filter->applyHorizontalScale(m_dx), -filter->applyVerticalScale(m_dy));
78 result.unite(offsetRect);
79
80 unsigned kernelSizeX = 0;
81 unsigned kernelSizeY = 0;
82 FEGaussianBlur::calculateKernelSize(filter, kernelSizeX, kernelSizeY, m_stdX, m_stdY);
83
84 // We take the half kernel size and multiply it with three, because we run box blur three times.
85 result.inflateX(3 * kernelSizeX * 0.5f);
86 result.inflateY(3 * kernelSizeY * 0.5f);
87 return result;
88 }
89
applySoftware()90 void FEDropShadow::applySoftware()
91 {
92 FilterEffect* in = inputEffect(0);
93
94 ImageBuffer* resultImage = createImageBufferResult();
95 if (!resultImage)
96 return;
97
98 Filter* filter = this->filter();
99 FloatSize blurRadius(filter->applyHorizontalScale(m_stdX), filter->applyVerticalScale(m_stdY));
100 FloatSize offset(filter->applyHorizontalScale(m_dx), filter->applyVerticalScale(m_dy));
101
102 FloatRect drawingRegion = drawingRegionOfInputImage(in->absolutePaintRect());
103 GraphicsContext* resultContext = resultImage->context();
104 ASSERT(resultContext);
105
106 SkAutoTUnref<SkImageFilter> blurFilter(new SkBlurImageFilter(blurRadius.width(), blurRadius.height()));
107 SkAutoTUnref<SkColorFilter> colorFilter(SkColorFilter::CreateModeFilter(m_shadowColor.rgb(), SkXfermode::kSrcIn_Mode));
108 SkPaint paint;
109 paint.setImageFilter(blurFilter.get());
110 paint.setColorFilter(colorFilter.get());
111 paint.setXfermodeMode(SkXfermode::kSrcOver_Mode);
112 RefPtr<Image> image = in->asImageBuffer()->copyImage(DontCopyBackingStore);
113
114 RefPtr<NativeImageSkia> nativeImage = image->nativeImageForCurrentFrame();
115
116 if (!nativeImage)
117 return;
118
119 resultContext->drawBitmap(nativeImage->bitmap(), drawingRegion.x() + offset.width(), drawingRegion.y() + offset.height(), &paint);
120 resultContext->drawBitmap(nativeImage->bitmap(), drawingRegion.x(), drawingRegion.y());
121 }
122
createImageFilter(SkiaImageFilterBuilder * builder)123 PassRefPtr<SkImageFilter> FEDropShadow::createImageFilter(SkiaImageFilterBuilder* builder)
124 {
125 RefPtr<SkImageFilter> input(builder->build(inputEffect(0), operatingColorSpace()));
126 float dx = filter()->applyHorizontalScale(m_dx);
127 float dy = filter()->applyVerticalScale(m_dy);
128 float stdX = filter()->applyHorizontalScale(m_stdX);
129 float stdY = filter()->applyHorizontalScale(m_stdY);
130 SkImageFilter::CropRect cropRect = getCropRect(builder->cropOffset());
131 return adoptRef(new SkDropShadowImageFilter(SkFloatToScalar(dx), SkFloatToScalar(dy), SkFloatToScalar(stdX), SkFloatToScalar(stdY), m_shadowColor.rgb(), input.get(), &cropRect));
132 }
133
134
externalRepresentation(TextStream & ts,int indent) const135 TextStream& FEDropShadow::externalRepresentation(TextStream& ts, int indent) const
136 {
137 writeIndent(ts, indent);
138 ts << "[feDropShadow";
139 FilterEffect::externalRepresentation(ts);
140 ts << " stdDeviation=\"" << m_stdX << ", " << m_stdY << "\" dx=\"" << m_dx << "\" dy=\"" << m_dy << "\" flood-color=\"" << m_shadowColor.nameForRenderTreeAsText() <<"\" flood-opacity=\"" << m_shadowOpacity << "]\n";
141 inputEffect(0)->externalRepresentation(ts, indent + 1);
142 return ts;
143 }
144
145 } // namespace WebCore
146