1 /*
2 * Copyright (C) 2006, 2007, 2008 Apple Computer, Inc. All rights reserved.
3 * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
4 * Copyright (C) 2013 Google, Inc. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
16 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
22 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
23 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include "config.h"
29 #include "platform/graphics/Pattern.h"
30
31 #include <v8.h>
32 #include "SkCanvas.h"
33 #include "SkColorShader.h"
34 #include "platform/graphics/skia/SkiaUtils.h"
35
36 namespace blink {
37
createBitmapPattern(PassRefPtr<Image> tileImage,RepeatMode repeatMode)38 PassRefPtr<Pattern> Pattern::createBitmapPattern(PassRefPtr<Image> tileImage, RepeatMode repeatMode)
39 {
40 return adoptRef(new Pattern(tileImage, repeatMode));
41 }
42
Pattern(PassRefPtr<Image> image,RepeatMode repeatMode)43 Pattern::Pattern(PassRefPtr<Image> image, RepeatMode repeatMode)
44 : m_repeatMode(repeatMode)
45 , m_externalMemoryAllocated(0)
46 {
47 if (image) {
48 m_tileImage = image->nativeImageForCurrentFrame();
49 }
50 }
51
~Pattern()52 Pattern::~Pattern()
53 {
54 if (m_externalMemoryAllocated)
55 v8::Isolate::GetCurrent()->AdjustAmountOfExternalAllocatedMemory(-m_externalMemoryAllocated);
56 }
57
shader()58 SkShader* Pattern::shader()
59 {
60 if (m_pattern)
61 return m_pattern.get();
62
63 SkMatrix localMatrix = affineTransformToSkMatrix(m_patternSpaceTransformation);
64
65 // If we don't have a bitmap, return a transparent shader.
66 if (!m_tileImage) {
67 m_pattern = adoptRef(new SkColorShader(SK_ColorTRANSPARENT));
68 } else if (m_repeatMode == RepeatModeXY) {
69 m_pattern = adoptRef(SkShader::CreateBitmapShader(m_tileImage->bitmap(),
70 SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode, &localMatrix));
71 } else {
72 // Skia does not have a "draw the tile only once" option. Clamp_TileMode
73 // repeats the last line of the image after drawing one tile. To avoid
74 // filling the space with arbitrary pixels, this workaround forces the
75 // image to have a line of transparent pixels on the "repeated" edge(s),
76 // thus causing extra space to be transparent filled.
77 SkShader::TileMode tileModeX = (m_repeatMode & RepeatModeX)
78 ? SkShader::kRepeat_TileMode
79 : SkShader::kClamp_TileMode;
80 SkShader::TileMode tileModeY = (m_repeatMode & RepeatModeY)
81 ? SkShader::kRepeat_TileMode
82 : SkShader::kClamp_TileMode;
83 int expandW = (m_repeatMode & RepeatModeX) ? 0 : 1;
84 int expandH = (m_repeatMode & RepeatModeY) ? 0 : 1;
85
86 // Create a transparent bitmap 1 pixel wider and/or taller than the
87 // original, then copy the orignal into it.
88 // FIXME: Is there a better way to pad (not scale) an image in skia?
89 SkImageInfo info = m_tileImage->bitmap().info();
90 info.fWidth += expandW;
91 info.fHeight += expandH;
92 // we explicitly require non-opaquness, since we are going to add a transparent strip.
93 info.fAlphaType = kPremul_SkAlphaType;
94
95 SkBitmap bm2;
96 bm2.allocPixels(info);
97 bm2.eraseARGB(0x00, 0x00, 0x00, 0x00);
98 SkCanvas canvas(bm2);
99 canvas.drawBitmap(m_tileImage->bitmap(), 0, 0);
100 bm2.setImmutable();
101 m_pattern = adoptRef(SkShader::CreateBitmapShader(bm2, tileModeX, tileModeY, &localMatrix));
102
103 // Clamp to int, since that's what the adjust function takes.
104 m_externalMemoryAllocated = static_cast<int>(std::min(static_cast<size_t>(INT_MAX), bm2.getSafeSize()));
105 v8::Isolate::GetCurrent()->AdjustAmountOfExternalAllocatedMemory(m_externalMemoryAllocated);
106 }
107 return m_pattern.get();
108 }
109
setPatternSpaceTransform(const AffineTransform & patternSpaceTransformation)110 void Pattern::setPatternSpaceTransform(const AffineTransform& patternSpaceTransformation)
111 {
112 if (patternSpaceTransformation == m_patternSpaceTransformation)
113 return;
114
115 m_patternSpaceTransformation = patternSpaceTransformation;
116 m_pattern.clear();
117 }
118
119 } // namespace blink
120