1 /* 2 * Copyright (C) 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 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 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include "config.h" 30 #include "Pattern.h" 31 32 #include "AffineTransform.h" 33 #include "Image.h" 34 #include "NativeImageSkia.h" 35 36 #include "SkCanvas.h" 37 #include "SkColor.h" 38 #include "SkColorShader.h" 39 #include "SkShader.h" 40 41 namespace WebCore { 42 43 void Pattern::platformDestroy() 44 { 45 SkSafeUnref(m_pattern); 46 m_pattern = 0; 47 } 48 49 PlatformPatternPtr Pattern::platformPattern(const AffineTransform& patternTransform) 50 { 51 if (m_pattern) 52 return m_pattern; 53 54 // Note: patternTransform is ignored since it seems to be applied elsewhere 55 // (when the pattern is used?). Applying it to the pattern (i.e. 56 // shader->setLocalMatrix) results in a double transformation. This can be 57 // seen, for instance, as an extra offset in: 58 // LayoutTests/fast/canvas/patternfill-repeat.html 59 // and expanded scale and skew in: 60 // LayoutTests/svg/W3C-SVG-1.1/pservers-grad-06-b.svg 61 62 SkBitmap* bm = m_tileImage->nativeImageForCurrentFrame(); 63 // If we don't have a bitmap, return a transparent shader. 64 if (!bm) 65 m_pattern = new SkColorShader(SkColorSetARGB(0, 0, 0, 0)); 66 67 else if (m_repeatX && m_repeatY) 68 m_pattern = SkShader::CreateBitmapShader(*bm, SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode); 69 70 else { 71 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_repeatX ? SkShader::kRepeat_TileMode : SkShader::kClamp_TileMode; 78 SkShader::TileMode tileModeY = m_repeatY ? SkShader::kRepeat_TileMode : SkShader::kClamp_TileMode; 79 int expandW = m_repeatX ? 0 : 1; 80 int expandH = m_repeatY ? 0 : 1; 81 82 // Create a transparent bitmap 1 pixel wider and/or taller than the 83 // original, then copy the orignal into it. 84 // FIXME: Is there a better way to pad (not scale) an image in skia? 85 SkBitmap bm2; 86 bm2.setConfig(bm->config(), bm->width() + expandW, bm->height() + expandH); 87 bm2.allocPixels(); 88 bm2.eraseARGB(0x00, 0x00, 0x00, 0x00); 89 SkCanvas canvas(bm2); 90 canvas.drawBitmap(*bm, 0, 0); 91 m_pattern = SkShader::CreateBitmapShader(bm2, tileModeX, tileModeY); 92 } 93 m_pattern->setLocalMatrix(m_patternSpaceTransformation); 94 return m_pattern; 95 } 96 97 void Pattern::setPlatformPatternSpaceTransform() 98 { 99 if (m_pattern) 100 m_pattern->setLocalMatrix(m_patternSpaceTransformation); 101 } 102 103 } // namespace WebCore 104
