1 /* 2 * Copyright 2012 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkSurface_Base.h" 9 #include "SkImagePriv.h" 10 #include "SkCanvas.h" 11 #include "SkDevice.h" 12 #include "SkMallocPixelRef.h" 13 14 static const size_t kIgnoreRowBytesValue = (size_t)~0; 15 16 class SkSurface_Raster : public SkSurface_Base { 17 public: 18 static bool Valid(const SkImage::Info&, size_t rb = kIgnoreRowBytesValue); 19 20 SkSurface_Raster(const SkImage::Info&, void*, size_t rb); 21 SkSurface_Raster(const SkImage::Info&, SkPixelRef*, size_t rb); 22 23 virtual SkCanvas* onNewCanvas() SK_OVERRIDE; 24 virtual SkSurface* onNewSurface(const SkImage::Info&) SK_OVERRIDE; 25 virtual SkImage* onNewImageShapshot() SK_OVERRIDE; 26 virtual void onDraw(SkCanvas*, SkScalar x, SkScalar y, 27 const SkPaint*) SK_OVERRIDE; 28 virtual void onCopyOnWrite(SkImage*, SkCanvas*) SK_OVERRIDE; 29 30 private: 31 SkBitmap fBitmap; 32 bool fWeOwnThePixels; 33 34 typedef SkSurface_Base INHERITED; 35 }; 36 37 /////////////////////////////////////////////////////////////////////////////// 38 39 bool SkSurface_Raster::Valid(const SkImage::Info& info, size_t rowBytes) { 40 static const size_t kMaxTotalSize = SK_MaxS32; 41 42 bool isOpaque; 43 SkBitmap::Config config = SkImageInfoToBitmapConfig(info, &isOpaque); 44 45 int shift = 0; 46 switch (config) { 47 case SkBitmap::kA8_Config: 48 shift = 0; 49 break; 50 case SkBitmap::kRGB_565_Config: 51 shift = 1; 52 break; 53 case SkBitmap::kARGB_8888_Config: 54 shift = 2; 55 break; 56 default: 57 return false; 58 } 59 60 // TODO: examine colorspace 61 62 if (kIgnoreRowBytesValue == rowBytes) { 63 return true; 64 } 65 66 uint64_t minRB = (uint64_t)info.fWidth << shift; 67 if (minRB > rowBytes) { 68 return false; 69 } 70 71 size_t alignedRowBytes = rowBytes >> shift << shift; 72 if (alignedRowBytes != rowBytes) { 73 return false; 74 } 75 76 uint64_t size = (uint64_t)info.fHeight * rowBytes; 77 if (size > kMaxTotalSize) { 78 return false; 79 } 80 81 return true; 82 } 83 84 SkSurface_Raster::SkSurface_Raster(const SkImage::Info& info, void* pixels, size_t rb) 85 : INHERITED(info.fWidth, info.fHeight) { 86 bool isOpaque; 87 SkBitmap::Config config = SkImageInfoToBitmapConfig(info, &isOpaque); 88 89 fBitmap.setConfig(config, info.fWidth, info.fHeight, rb); 90 fBitmap.setPixels(pixels); 91 fBitmap.setIsOpaque(isOpaque); 92 fWeOwnThePixels = false; // We are "Direct" 93 } 94 95 SkSurface_Raster::SkSurface_Raster(const SkImage::Info& info, SkPixelRef* pr, size_t rb) 96 : INHERITED(info.fWidth, info.fHeight) { 97 bool isOpaque; 98 SkBitmap::Config config = SkImageInfoToBitmapConfig(info, &isOpaque); 99 100 fBitmap.setConfig(config, info.fWidth, info.fHeight, rb); 101 fBitmap.setPixelRef(pr); 102 fBitmap.setIsOpaque(isOpaque); 103 fWeOwnThePixels = true; 104 105 if (!isOpaque) { 106 fBitmap.eraseColor(SK_ColorTRANSPARENT); 107 } 108 } 109 110 SkCanvas* SkSurface_Raster::onNewCanvas() { 111 return SkNEW_ARGS(SkCanvas, (fBitmap)); 112 } 113 114 SkSurface* SkSurface_Raster::onNewSurface(const SkImage::Info& info) { 115 return SkSurface::NewRaster(info); 116 } 117 118 void SkSurface_Raster::onDraw(SkCanvas* canvas, SkScalar x, SkScalar y, 119 const SkPaint* paint) { 120 canvas->drawBitmap(fBitmap, x, y, paint); 121 } 122 123 SkImage* SkSurface_Raster::onNewImageShapshot() { 124 return SkNewImageFromBitmap(fBitmap, fWeOwnThePixels); 125 } 126 127 void SkSurface_Raster::onCopyOnWrite(SkImage* image, SkCanvas* canvas) { 128 // are we sharing pixelrefs with the image? 129 if (SkBitmapImageGetPixelRef(image) == fBitmap.pixelRef()) { 130 SkASSERT(fWeOwnThePixels); 131 SkBitmap prev(fBitmap); 132 prev.deepCopyTo(&fBitmap, prev.config()); 133 // Now fBitmap is a deep copy of itself (and therefore different from 134 // what is being used by the image. Next we update the canvas to use 135 // this as its backend, so we can't modify the image's pixels anymore. 136 canvas->getDevice()->replaceBitmapBackendForRasterSurface(fBitmap); 137 } 138 } 139 140 /////////////////////////////////////////////////////////////////////////////// 141 142 SkSurface* SkSurface::NewRasterDirect(const SkImage::Info& info, void* pixels, size_t rowBytes) { 143 if (!SkSurface_Raster::Valid(info, rowBytes)) { 144 return NULL; 145 } 146 if (NULL == pixels) { 147 return NULL; 148 } 149 150 return SkNEW_ARGS(SkSurface_Raster, (info, pixels, rowBytes)); 151 } 152 153 SkSurface* SkSurface::NewRaster(const SkImage::Info& info) { 154 if (!SkSurface_Raster::Valid(info)) { 155 return NULL; 156 } 157 158 static const size_t kMaxTotalSize = SK_MaxS32; 159 size_t rowBytes = SkImageMinRowBytes(info); 160 uint64_t size64 = (uint64_t)info.fHeight * rowBytes; 161 if (size64 > kMaxTotalSize) { 162 return NULL; 163 } 164 165 size_t size = (size_t)size64; 166 void* pixels = sk_malloc_throw(size); 167 if (NULL == pixels) { 168 return NULL; 169 } 170 171 SkAutoTUnref<SkPixelRef> pr(SkNEW_ARGS(SkMallocPixelRef, (pixels, size, NULL, true))); 172 return SkNEW_ARGS(SkSurface_Raster, (info, pr, rowBytes)); 173 } 174