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 class SkSurface_Raster : public SkSurface_Base { 15 public: 16 SkSurface_Raster(const SkImageInfo&, void*, size_t rb, 17 void (*releaseProc)(void* pixels, void* context), void* context, 18 const SkSurfaceProps*); 19 SkSurface_Raster(const SkImageInfo& info, sk_sp<SkPixelRef>, const SkSurfaceProps*); 20 21 SkCanvas* onNewCanvas() override; 22 sk_sp<SkSurface> onNewSurface(const SkImageInfo&) override; 23 sk_sp<SkImage> onNewImageSnapshot() override; 24 void onDraw(SkCanvas*, SkScalar x, SkScalar y, const SkPaint*) override; 25 void onCopyOnWrite(ContentChangeMode) override; 26 void onRestoreBackingMutability() override; 27 28 private: 29 SkBitmap fBitmap; 30 size_t fRowBytes; 31 bool fWeOwnThePixels; 32 33 typedef SkSurface_Base INHERITED; 34 }; 35 36 /////////////////////////////////////////////////////////////////////////////// 37 38 bool SkSurfaceValidateRasterInfo(const SkImageInfo& info, size_t rowBytes) { 39 if (info.isEmpty()) { 40 return false; 41 } 42 43 static const size_t kMaxTotalSize = SK_MaxS32; 44 45 int shift = 0; 46 switch (info.colorType()) { 47 case kAlpha_8_SkColorType: 48 if (info.colorSpace()) { 49 return false; 50 } 51 shift = 0; 52 break; 53 case kRGB_565_SkColorType: 54 if (info.colorSpace()) { 55 return false; 56 } 57 shift = 1; 58 break; 59 case kN32_SkColorType: 60 if (info.colorSpace() && !info.colorSpace()->gammaCloseToSRGB()) { 61 return false; 62 } 63 shift = 2; 64 break; 65 case kRGBA_F16_SkColorType: 66 if (!info.colorSpace() || !info.colorSpace()->gammaIsLinear()) { 67 return false; 68 } 69 shift = 3; 70 break; 71 default: 72 return false; 73 } 74 75 if (kIgnoreRowBytesValue == rowBytes) { 76 return true; 77 } 78 79 uint64_t minRB = (uint64_t)info.width() << shift; 80 if (minRB > rowBytes) { 81 return false; 82 } 83 84 size_t alignedRowBytes = rowBytes >> shift << shift; 85 if (alignedRowBytes != rowBytes) { 86 return false; 87 } 88 89 uint64_t size = sk_64_mul(info.height(), rowBytes); 90 if (size > kMaxTotalSize) { 91 return false; 92 } 93 94 return true; 95 } 96 97 SkSurface_Raster::SkSurface_Raster(const SkImageInfo& info, void* pixels, size_t rb, 98 void (*releaseProc)(void* pixels, void* context), void* context, 99 const SkSurfaceProps* props) 100 : INHERITED(info, props) 101 { 102 fBitmap.installPixels(info, pixels, rb, releaseProc, context); 103 fRowBytes = 0; // don't need to track the rowbytes 104 fWeOwnThePixels = false; // We are "Direct" 105 } 106 107 SkSurface_Raster::SkSurface_Raster(const SkImageInfo& info, sk_sp<SkPixelRef> pr, 108 const SkSurfaceProps* props) 109 : INHERITED(pr->width(), pr->height(), props) 110 { 111 fBitmap.setInfo(info, pr->rowBytes()); 112 fRowBytes = pr->rowBytes(); // we track this, so that subsequent re-allocs will match 113 fBitmap.setPixelRef(std::move(pr), 0, 0); 114 fWeOwnThePixels = true; 115 } 116 117 SkCanvas* SkSurface_Raster::onNewCanvas() { return new SkCanvas(fBitmap, this->props()); } 118 119 sk_sp<SkSurface> SkSurface_Raster::onNewSurface(const SkImageInfo& info) { 120 return SkSurface::MakeRaster(info, &this->props()); 121 } 122 123 void SkSurface_Raster::onDraw(SkCanvas* canvas, SkScalar x, SkScalar y, 124 const SkPaint* paint) { 125 canvas->drawBitmap(fBitmap, x, y, paint); 126 } 127 128 sk_sp<SkImage> SkSurface_Raster::onNewImageSnapshot() { 129 SkCopyPixelsMode cpm = kIfMutable_SkCopyPixelsMode; 130 if (fWeOwnThePixels) { 131 // SkImage_raster requires these pixels are immutable for its full lifetime. 132 // We'll undo this via onRestoreBackingMutability() if we can avoid the COW. 133 if (SkPixelRef* pr = fBitmap.pixelRef()) { 134 pr->setTemporarilyImmutable(); 135 } 136 } else { 137 cpm = kAlways_SkCopyPixelsMode; 138 } 139 140 // Our pixels are in memory, so read access on the snapshot SkImage could be cheap. 141 // Lock the shared pixel ref to ensure peekPixels() is usable. 142 return SkMakeImageFromRasterBitmap(fBitmap, cpm); 143 } 144 145 void SkSurface_Raster::onRestoreBackingMutability() { 146 SkASSERT(!this->hasCachedImage()); // Shouldn't be any snapshots out there. 147 if (SkPixelRef* pr = fBitmap.pixelRef()) { 148 pr->restoreMutability(); 149 } 150 } 151 152 void SkSurface_Raster::onCopyOnWrite(ContentChangeMode mode) { 153 // are we sharing pixelrefs with the image? 154 sk_sp<SkImage> cached(this->refCachedImage()); 155 SkASSERT(cached); 156 if (SkBitmapImageGetPixelRef(cached.get()) == fBitmap.pixelRef()) { 157 SkASSERT(fWeOwnThePixels); 158 if (kDiscard_ContentChangeMode == mode) { 159 fBitmap.allocPixels(); 160 } else { 161 SkBitmap prev(fBitmap); 162 fBitmap.allocPixels(); 163 SkASSERT(prev.info() == fBitmap.info()); 164 SkASSERT(prev.rowBytes() == fBitmap.rowBytes()); 165 memcpy(fBitmap.getPixels(), prev.getPixels(), fBitmap.getSafeSize()); 166 } 167 SkASSERT(fBitmap.rowBytes() == fRowBytes); // be sure we always use the same value 168 169 // Now fBitmap is a deep copy of itself (and therefore different from 170 // what is being used by the image. Next we update the canvas to use 171 // this as its backend, so we can't modify the image's pixels anymore. 172 SkASSERT(this->getCachedCanvas()); 173 this->getCachedCanvas()->getDevice()->replaceBitmapBackendForRasterSurface(fBitmap); 174 } 175 } 176 177 /////////////////////////////////////////////////////////////////////////////// 178 179 sk_sp<SkSurface> SkSurface::MakeRasterDirectReleaseProc(const SkImageInfo& info, void* pixels, 180 size_t rb, void (*releaseProc)(void* pixels, void* context), void* context, 181 const SkSurfaceProps* props) { 182 if (nullptr == releaseProc) { 183 context = nullptr; 184 } 185 if (!SkSurfaceValidateRasterInfo(info, rb)) { 186 return nullptr; 187 } 188 if (nullptr == pixels) { 189 return nullptr; 190 } 191 192 return sk_make_sp<SkSurface_Raster>(info, pixels, rb, releaseProc, context, props); 193 } 194 195 sk_sp<SkSurface> SkSurface::MakeRasterDirect(const SkImageInfo& info, void* pixels, size_t rowBytes, 196 const SkSurfaceProps* props) { 197 return MakeRasterDirectReleaseProc(info, pixels, rowBytes, nullptr, nullptr, props); 198 } 199 200 sk_sp<SkSurface> SkSurface::MakeRaster(const SkImageInfo& info, size_t rowBytes, 201 const SkSurfaceProps* props) { 202 if (!SkSurfaceValidateRasterInfo(info)) { 203 return nullptr; 204 } 205 206 sk_sp<SkPixelRef> pr = SkMallocPixelRef::MakeZeroed(info, rowBytes); 207 if (!pr) { 208 return nullptr; 209 } 210 if (rowBytes) { 211 SkASSERT(pr->rowBytes() == rowBytes); 212 } 213 return sk_make_sp<SkSurface_Raster>(info, std::move(pr), props); 214 } 215