1/* 2 * Copyright 2015 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 "SkImage_Base.h" 9#include "SkBitmap.h" 10#include "SkCanvas.h" 11#include "SkData.h" 12#include "SkImageCacherator.h" 13#include "SkImagePriv.h" 14#include "SkPixelRef.h" 15#include "SkSurface.h" 16 17class SkImage_Generator : public SkImage_Base { 18public: 19 SkImage_Generator(SkImageCacherator* cache) 20 : INHERITED(cache->info().width(), cache->info().height(), cache->uniqueID()) 21 , fCache(cache) // take ownership 22 {} 23 24 bool onReadPixels(const SkImageInfo&, void*, size_t, int srcX, int srcY, CachingHint) const override; 25 const void* onPeekPixels(SkImageInfo*, size_t* /*rowBytes*/) const override; 26 SkImageCacherator* peekCacherator() const override { return fCache; } 27 SkData* onRefEncoded(GrContext*) const override; 28 bool isOpaque() const override { return fCache->info().isOpaque(); } 29 SkImage* onNewSubset(const SkIRect&) const override; 30 bool getROPixels(SkBitmap*, CachingHint) const override; 31 GrTexture* asTextureRef(GrContext*, const GrTextureParams&) const override; 32 bool onIsLazyGenerated() const override { return true; } 33 34private: 35 SkAutoTDelete<SkImageCacherator> fCache; 36 37 typedef SkImage_Base INHERITED; 38}; 39 40/////////////////////////////////////////////////////////////////////////////// 41 42bool SkImage_Generator::onReadPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRB, 43 int srcX, int srcY, CachingHint chint) const { 44 SkBitmap bm; 45 if (kDisallow_CachingHint == chint) { 46 if (fCache->lockAsBitmapOnlyIfAlreadyCached(&bm)) { 47 return bm.readPixels(dstInfo, dstPixels, dstRB, srcX, srcY); 48 } else { 49 // Try passing the caller's buffer directly down to the generator. If this fails we 50 // may still succeed in the general case, as the generator may prefer some other 51 // config, which we could then convert via SkBitmap::readPixels. 52 if (fCache->directGeneratePixels(dstInfo, dstPixels, dstRB, srcX, srcY)) { 53 return true; 54 } 55 // else fall through 56 } 57 } 58 59 if (this->getROPixels(&bm, chint)) { 60 return bm.readPixels(dstInfo, dstPixels, dstRB, srcX, srcY); 61 } 62 return false; 63} 64 65const void* SkImage_Generator::onPeekPixels(SkImageInfo* infoPtr, size_t* rowBytesPtr) const { 66 return NULL; 67} 68 69SkData* SkImage_Generator::onRefEncoded(GrContext* ctx) const { 70 return fCache->refEncoded(ctx); 71} 72 73bool SkImage_Generator::getROPixels(SkBitmap* bitmap, CachingHint chint) const { 74 return fCache->lockAsBitmap(bitmap, this, chint); 75} 76 77GrTexture* SkImage_Generator::asTextureRef(GrContext* ctx, const GrTextureParams& params) const { 78 return fCache->lockAsTexture(ctx, params, this); 79} 80 81SkImage* SkImage_Generator::onNewSubset(const SkIRect& subset) const { 82 // TODO: make this lazy, by wrapping the subset inside a new generator or something 83 // For now, we do effectively what we did before, make it a raster 84 85 const SkImageInfo info = SkImageInfo::MakeN32(subset.width(), subset.height(), 86 this->isOpaque() ? kOpaque_SkAlphaType : kPremul_SkAlphaType); 87 SkAutoTUnref<SkSurface> surface(SkSurface::NewRaster(info)); 88 if (!surface) { 89 return nullptr; 90 } 91 surface->getCanvas()->clear(0); 92 surface->getCanvas()->drawImage(this, SkIntToScalar(-subset.x()), SkIntToScalar(-subset.y()), 93 nullptr); 94 return surface->newImageSnapshot(); 95} 96 97SkImage* SkImage::NewFromGenerator(SkImageGenerator* generator, const SkIRect* subset) { 98 SkImageCacherator* cache = SkImageCacherator::NewFromGenerator(generator, subset); 99 if (!cache) { 100 return nullptr; 101 } 102 return new SkImage_Generator(cache); 103} 104