1 // Copyright (C) 2013 Google Inc. All rights reserved. 2 // 3 // Redistribution and use in source and binary forms, with or without 4 // modification, are permitted provided that the following conditions are 5 // met: 6 // 7 // * Redistributions of source code must retain the above copyright 8 // notice, this list of conditions and the following disclaimer. 9 // * Redistributions in binary form must reproduce the above 10 // copyright notice, this list of conditions and the following disclaimer 11 // in the documentation and/or other materials provided with the 12 // distribution. 13 // * Neither the name of Google Inc. nor the names of its 14 // contributors may be used to endorse or promote products derived from 15 // this software without specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 29 #ifndef GraphicsContextState_h 30 #define GraphicsContextState_h 31 32 #include "core/platform/graphics/Gradient.h" 33 #include "core/platform/graphics/GraphicsTypes.h" 34 #include "core/platform/graphics/Path.h" 35 #include "core/platform/graphics/Pattern.h" 36 #include "core/platform/graphics/StrokeData.h" 37 #include "third_party/skia/include/core/SkColorPriv.h" 38 #include "third_party/skia/include/core/SkDrawLooper.h" 39 #include "third_party/skia/include/effects/SkDashPathEffect.h" 40 #include "wtf/PassOwnPtr.h" 41 #include "wtf/RefPtr.h" 42 43 namespace WebCore { 44 45 // Encapsulates the state information we store for each pushed graphics state. 46 // Only GraphicsContext can use this class. 47 class GraphicsContextState { 48 private: 49 friend class GraphicsContext; 50 51 GraphicsContextState() 52 : m_fillColor(Color::black) 53 , m_fillRule(RULE_NONZERO) 54 , m_textDrawingMode(TextModeFill) 55 , m_alpha(1) 56 , m_xferMode(SkXfermode::kSrcOver_Mode) 57 , m_compositeOperator(CompositeSourceOver) 58 , m_blendMode(BlendModeNormal) 59 , m_clip(SkRect::MakeEmpty()) 60 #if USE(LOW_QUALITY_IMAGE_INTERPOLATION) 61 , m_interpolationQuality(InterpolationLow) 62 #else 63 , m_interpolationQuality(InterpolationHigh) 64 #endif 65 , m_shouldAntialias(true) 66 , m_shouldSmoothFonts(true) 67 { 68 } 69 70 GraphicsContextState(const GraphicsContextState& other) 71 : m_strokeData(other.m_strokeData) 72 , m_fillColor(other.m_fillColor) 73 , m_fillRule(other.m_fillRule) 74 , m_fillGradient(other.m_fillGradient) 75 , m_fillPattern(other.m_fillPattern) 76 , m_looper(other.m_looper) 77 , m_textDrawingMode(other.m_textDrawingMode) 78 , m_alpha(other.m_alpha) 79 , m_xferMode(other.m_xferMode) 80 , m_compositeOperator(other.m_compositeOperator) 81 , m_blendMode(other.m_blendMode) 82 , m_clip(other.m_clip) 83 , m_interpolationQuality(other.m_interpolationQuality) 84 , m_shouldAntialias(other.m_shouldAntialias) 85 , m_shouldSmoothFonts(other.m_shouldSmoothFonts) 86 { 87 } 88 89 // Helper function for applying the state's alpha value to the given input 90 // color to produce a new output color. 91 SkColor applyAlpha(SkColor c) const 92 { 93 int s = roundf(m_alpha * 256); 94 if (s >= 256) 95 return c; 96 if (s < 0) 97 return 0; 98 99 int a = SkAlphaMul(SkColorGetA(c), s); 100 return (c & 0x00FFFFFF) | (a << 24); 101 } 102 103 // Returns a new State with all of this object's inherited properties copied. 104 PassOwnPtr<GraphicsContextState> clone() { return adoptPtr(new GraphicsContextState(*this)); } 105 106 // Not supported. No implementations. 107 void operator=(const GraphicsContextState&); 108 109 // Stroke. 110 StrokeData m_strokeData; 111 112 // Fill. 113 Color m_fillColor; 114 WindRule m_fillRule; 115 RefPtr<Gradient> m_fillGradient; 116 RefPtr<Pattern> m_fillPattern; 117 118 // Shadow. (This will need tweaking if we use draw loopers for other things.) 119 RefPtr<SkDrawLooper> m_looper; 120 121 // Text. (See TextModeFill & friends.) 122 TextDrawingModeFlags m_textDrawingMode; 123 124 // Common shader state. 125 float m_alpha; 126 SkXfermode::Mode m_xferMode; 127 128 // Compositing control, for the CSS and Canvas compositing spec. 129 CompositeOperator m_compositeOperator; 130 BlendMode m_blendMode; 131 132 // If non-empty, the current State is clipped to this image. 133 SkBitmap m_imageBufferClip; 134 135 // If m_imageBufferClip is non-empty, this is the region the image is clipped to. 136 SkRect m_clip; 137 138 // Image interpolation control. 139 InterpolationQuality m_interpolationQuality; 140 141 bool m_shouldAntialias : 1; 142 bool m_shouldSmoothFonts : 1; 143 }; 144 145 } // namespace WebCore 146 147 #endif // GraphicsContextState_h 148 149