1 /*
2 * Copyright (c) 2006,2007,2008, 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 are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include "config.h"
32
33 #include "platform/graphics/skia/SkiaUtils.h"
34
35 #include "SkColorPriv.h"
36 #include "SkRegion.h"
37 #include "platform/graphics/GraphicsContext.h"
38 #include "platform/graphics/ImageBuffer.h"
39
40 namespace WebCore {
41
42 static const struct CompositOpToXfermodeMode {
43 uint8_t mCompositOp;
44 uint8_t m_xfermodeMode;
45 } gMapCompositOpsToXfermodeModes[] = {
46 { CompositeClear, SkXfermode::kClear_Mode },
47 { CompositeCopy, SkXfermode::kSrc_Mode },
48 { CompositeSourceOver, SkXfermode::kSrcOver_Mode },
49 { CompositeSourceIn, SkXfermode::kSrcIn_Mode },
50 { CompositeSourceOut, SkXfermode::kSrcOut_Mode },
51 { CompositeSourceAtop, SkXfermode::kSrcATop_Mode },
52 { CompositeDestinationOver, SkXfermode::kDstOver_Mode },
53 { CompositeDestinationIn, SkXfermode::kDstIn_Mode },
54 { CompositeDestinationOut, SkXfermode::kDstOut_Mode },
55 { CompositeDestinationAtop, SkXfermode::kDstATop_Mode },
56 { CompositeXOR, SkXfermode::kXor_Mode },
57 { CompositePlusDarker, SkXfermode::kDarken_Mode },
58 { CompositePlusLighter, SkXfermode::kPlus_Mode }
59 };
60
61 // keep this array in sync with blink::WebBlendMode enum in public/platform/WebBlendMode.h
62 static const uint8_t gMapBlendOpsToXfermodeModes[] = {
63 SkXfermode::kClear_Mode, // blink::WebBlendModeNormal
64 SkXfermode::kMultiply_Mode, // blink::WebBlendModeMultiply
65 SkXfermode::kScreen_Mode, // blink::WebBlendModeScreen
66 SkXfermode::kOverlay_Mode, // blink::WebBlendModeOverlay
67 SkXfermode::kDarken_Mode, // blink::WebBlendModeDarken
68 SkXfermode::kLighten_Mode, // blink::WebBlendModeLighten
69 SkXfermode::kColorDodge_Mode, // blink::WebBlendModeColorDodge
70 SkXfermode::kColorBurn_Mode, // blink::WebBlendModeColorBurn
71 SkXfermode::kHardLight_Mode, // blink::WebBlendModeHardLight
72 SkXfermode::kSoftLight_Mode, // blink::WebBlendModeSoftLight
73 SkXfermode::kDifference_Mode, // blink::WebBlendModeDifference
74 SkXfermode::kExclusion_Mode, // blink::WebBlendModeExclusion
75 SkXfermode::kHue_Mode, // blink::WebBlendModeHue
76 SkXfermode::kSaturation_Mode, // blink::WebBlendModeSaturation
77 SkXfermode::kColor_Mode, // blink::WebBlendModeColor
78 SkXfermode::kLuminosity_Mode // blink::WebBlendModeLuminosity
79 };
80
WebCoreCompositeToSkiaComposite(CompositeOperator op,blink::WebBlendMode blendMode)81 PassRefPtr<SkXfermode> WebCoreCompositeToSkiaComposite(CompositeOperator op, blink::WebBlendMode blendMode)
82 {
83 if (blendMode != blink::WebBlendModeNormal) {
84 if ((uint8_t)blendMode >= SK_ARRAY_COUNT(gMapBlendOpsToXfermodeModes)) {
85 SkDEBUGF(("GraphicsContext::setPlatformCompositeOperation unknown blink::WebBlendMode %d\n", blendMode));
86 return adoptRef(SkXfermode::Create(SkXfermode::kSrcOver_Mode));
87 }
88 SkXfermode::Mode mode = (SkXfermode::Mode)gMapBlendOpsToXfermodeModes[(uint8_t)blendMode];
89 return adoptRef(SkXfermode::Create(mode));
90 }
91
92 const CompositOpToXfermodeMode* table = gMapCompositOpsToXfermodeModes;
93
94 for (unsigned i = 0; i < SK_ARRAY_COUNT(gMapCompositOpsToXfermodeModes); i++) {
95 if (table[i].mCompositOp == op)
96 return adoptRef(SkXfermode::Create((SkXfermode::Mode)table[i].m_xfermodeMode));
97 }
98
99 SkDEBUGF(("GraphicsContext::setPlatformCompositeOperation unknown CompositeOperator %d\n", op));
100 return adoptRef(SkXfermode::Create(SkXfermode::kSrcOver_Mode)); // fall-back
101 }
102
InvScaleByte(U8CPU component,uint32_t scale)103 static U8CPU InvScaleByte(U8CPU component, uint32_t scale)
104 {
105 SkASSERT(component == (uint8_t)component);
106 return (component * scale + 0x8000) >> 16;
107 }
108
SkPMColorToColor(SkPMColor pm)109 SkColor SkPMColorToColor(SkPMColor pm)
110 {
111 if (!pm)
112 return 0;
113 unsigned a = SkGetPackedA32(pm);
114 if (!a) {
115 // A zero alpha value when there are non-zero R, G, or B channels is an
116 // invalid premultiplied color (since all channels should have been
117 // multiplied by 0 if a=0).
118 SkASSERT(false);
119 // In production, return 0 to protect against division by zero.
120 return 0;
121 }
122
123 uint32_t scale = (255 << 16) / a;
124
125 return SkColorSetARGB(a,
126 InvScaleByte(SkGetPackedR32(pm), scale),
127 InvScaleByte(SkGetPackedG32(pm), scale),
128 InvScaleByte(SkGetPackedB32(pm), scale));
129 }
130
SkPathContainsPoint(const SkPath & originalPath,const FloatPoint & point,SkPath::FillType ft)131 bool SkPathContainsPoint(const SkPath& originalPath, const FloatPoint& point, SkPath::FillType ft)
132 {
133 SkRect bounds = originalPath.getBounds();
134
135 // We can immediately return false if the point is outside the bounding
136 // rect. We don't use bounds.contains() here, since it would exclude
137 // points on the right and bottom edges of the bounding rect, and we want
138 // to include them.
139 SkScalar fX = SkFloatToScalar(point.x());
140 SkScalar fY = SkFloatToScalar(point.y());
141 if (fX < bounds.fLeft || fX > bounds.fRight || fY < bounds.fTop || fY > bounds.fBottom)
142 return false;
143
144 // Scale the path to a large size before hit testing for two reasons:
145 // 1) Skia has trouble with coordinates close to the max signed 16-bit values, so we scale larger paths down.
146 // TODO: when Skia is patched to work properly with large values, this will not be necessary.
147 // 2) Skia does not support analytic hit testing, so we scale paths up to do raster hit testing with subpixel accuracy.
148 SkScalar biggestCoord = std::max(std::max(std::max(bounds.fRight, bounds.fBottom), -bounds.fLeft), -bounds.fTop);
149 if (SkScalarNearlyZero(biggestCoord))
150 return false;
151 biggestCoord = std::max(std::max(biggestCoord, fX + 1), fY + 1);
152
153 const SkScalar kMaxCoordinate = SkIntToScalar(1 << 15);
154 SkScalar scale = SkScalarDiv(kMaxCoordinate, biggestCoord);
155
156 SkRegion rgn;
157 SkRegion clip;
158 SkMatrix m;
159 SkPath scaledPath(originalPath);
160
161 scaledPath.setFillType(ft);
162 m.setScale(scale, scale);
163 scaledPath.transform(m, 0);
164
165 int x = static_cast<int>(floorf(0.5f + point.x() * scale));
166 int y = static_cast<int>(floorf(0.5f + point.y() * scale));
167 clip.setRect(x - 1, y - 1, x + 1, y + 1);
168
169 return rgn.setPath(scaledPath, clip);
170 }
171
affineTransformToSkMatrix(const AffineTransform & source)172 SkMatrix affineTransformToSkMatrix(const AffineTransform& source)
173 {
174 SkMatrix result;
175
176 result.setScaleX(WebCoreDoubleToSkScalar(source.a()));
177 result.setSkewX(WebCoreDoubleToSkScalar(source.c()));
178 result.setTranslateX(WebCoreDoubleToSkScalar(source.e()));
179
180 result.setScaleY(WebCoreDoubleToSkScalar(source.d()));
181 result.setSkewY(WebCoreDoubleToSkScalar(source.b()));
182 result.setTranslateY(WebCoreDoubleToSkScalar(source.f()));
183
184 // FIXME: Set perspective properly.
185 result.setPerspX(0);
186 result.setPerspY(0);
187 result.set(SkMatrix::kMPersp2, SK_Scalar1);
188
189 return result;
190 }
191
192 } // namespace WebCore
193