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      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 "SkBitmap.h"
      9 #include "SkBitmapCache.h"
     10 #include "SkCanvas.h"
     11 #include "SkData.h"
     12 #include "SkImageEncoder.h"
     13 #include "SkImageGenerator.h"
     14 #include "SkImagePriv.h"
     15 #include "SkImageShader.h"
     16 #include "SkImage_Base.h"
     17 #include "SkNextID.h"
     18 #include "SkPixelRef.h"
     19 #include "SkPixelSerializer.h"
     20 #include "SkReadPixelsRec.h"
     21 #include "SkString.h"
     22 #include "SkSurface.h"
     23 
     24 #if SK_SUPPORT_GPU
     25 #include "GrTexture.h"
     26 #include "GrContext.h"
     27 #include "SkImage_Gpu.h"
     28 #endif
     29 
     30 SkImage::SkImage(int width, int height, uint32_t uniqueID)
     31     : fWidth(width)
     32     , fHeight(height)
     33     , fUniqueID(kNeedNewImageUniqueID == uniqueID ? SkNextID::ImageID() : uniqueID)
     34 {
     35     SkASSERT(width > 0);
     36     SkASSERT(height > 0);
     37 }
     38 
     39 const void* SkImage::peekPixels(SkImageInfo* info, size_t* rowBytes) const {
     40     SkImageInfo infoStorage;
     41     size_t rowBytesStorage;
     42     if (nullptr == info) {
     43         info = &infoStorage;
     44     }
     45     if (nullptr == rowBytes) {
     46         rowBytes = &rowBytesStorage;
     47     }
     48     return as_IB(this)->onPeekPixels(info, rowBytes);
     49 }
     50 
     51 bool SkImage::readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
     52                            int srcX, int srcY, CachingHint chint) const {
     53     SkReadPixelsRec rec(dstInfo, dstPixels, dstRowBytes, srcX, srcY);
     54     if (!rec.trim(this->width(), this->height())) {
     55         return false;
     56     }
     57     return as_IB(this)->onReadPixels(rec.fInfo, rec.fPixels, rec.fRowBytes, rec.fX, rec.fY, chint);
     58 }
     59 
     60 bool SkImage::scalePixels(const SkPixmap& dst, SkFilterQuality quality, CachingHint chint) const {
     61     if (this->width() == dst.width() && this->height() == dst.height()) {
     62         return this->readPixels(dst, 0, 0, chint);
     63     }
     64 
     65     // Idea: If/when SkImageGenerator supports a native-scaling API (where the generator itself
     66     //       can scale more efficiently) we should take advantage of it here.
     67     //
     68     SkBitmap bm;
     69     if (as_IB(this)->getROPixels(&bm, chint)) {
     70         bm.lockPixels();
     71         SkPixmap pmap;
     72         // Note: By calling the pixmap scaler, we never cache the final result, so the chint
     73         //       is (currently) only being applied to the getROPixels. If we get a request to
     74         //       also attempt to cache the final (scaled) result, we would add that logic here.
     75         //
     76         return bm.peekPixels(&pmap) && pmap.scalePixels(dst, quality);
     77     }
     78     return false;
     79 }
     80 
     81 void SkImage::preroll(GrContext* ctx) const {
     82     // For now, and to maintain parity w/ previous pixelref behavior, we just force the image
     83     // to produce a cached raster-bitmap form, so that drawing to a raster canvas should be fast.
     84     //
     85     SkBitmap bm;
     86     if (as_IB(this)->getROPixels(&bm)) {
     87         bm.lockPixels();
     88         bm.unlockPixels();
     89     }
     90 }
     91 
     92 ///////////////////////////////////////////////////////////////////////////////////////////////////
     93 
     94 SkShader* SkImage::newShader(SkShader::TileMode tileX,
     95                              SkShader::TileMode tileY,
     96                              const SkMatrix* localMatrix) const {
     97     return SkImageShader::Create(this, tileX, tileY, localMatrix);
     98 }
     99 
    100 SkData* SkImage::encode(SkImageEncoder::Type type, int quality) const {
    101     SkBitmap bm;
    102     if (as_IB(this)->getROPixels(&bm)) {
    103         return SkImageEncoder::EncodeData(bm, type, quality);
    104     }
    105     return nullptr;
    106 }
    107 
    108 SkData* SkImage::encode(SkPixelSerializer* serializer) const {
    109     SkAutoTUnref<SkPixelSerializer> defaultSerializer;
    110     SkPixelSerializer* effectiveSerializer = serializer;
    111     if (!effectiveSerializer) {
    112         defaultSerializer.reset(SkImageEncoder::CreatePixelSerializer());
    113         SkASSERT(defaultSerializer.get());
    114         effectiveSerializer = defaultSerializer.get();
    115     }
    116     SkAutoTUnref<SkData> encoded(this->refEncoded());
    117     if (encoded && effectiveSerializer->useEncodedData(encoded->data(), encoded->size())) {
    118         return encoded.detach();
    119     }
    120 
    121     SkBitmap bm;
    122     SkAutoPixmapUnlock apu;
    123     if (as_IB(this)->getROPixels(&bm) && bm.requestLock(&apu)) {
    124         return effectiveSerializer->encode(apu.pixmap());
    125     }
    126 
    127     return nullptr;
    128 }
    129 
    130 SkData* SkImage::refEncoded() const {
    131     GrContext* ctx = nullptr;   // should we allow the caller to pass in a ctx?
    132     return as_IB(this)->onRefEncoded(ctx);
    133 }
    134 
    135 SkImage* SkImage::NewFromEncoded(SkData* encoded, const SkIRect* subset) {
    136     if (nullptr == encoded || 0 == encoded->size()) {
    137         return nullptr;
    138     }
    139     SkImageGenerator* generator = SkImageGenerator::NewFromEncoded(encoded);
    140     return generator ? SkImage::NewFromGenerator(generator, subset) : nullptr;
    141 }
    142 
    143 const char* SkImage::toString(SkString* str) const {
    144     str->appendf("image: (id:%d (%d, %d) %s)", this->uniqueID(), this->width(), this->height(),
    145                  this->isOpaque() ? "opaque" : "");
    146     return str->c_str();
    147 }
    148 
    149 SkImage* SkImage::newSubset(const SkIRect& subset) const {
    150     if (subset.isEmpty()) {
    151         return nullptr;
    152     }
    153 
    154     const SkIRect bounds = SkIRect::MakeWH(this->width(), this->height());
    155     if (!bounds.contains(subset)) {
    156         return nullptr;
    157     }
    158 
    159     // optimization : return self if the subset == our bounds
    160     if (bounds == subset) {
    161         return SkRef(const_cast<SkImage*>(this));
    162     }
    163     return as_IB(this)->onNewSubset(subset);
    164 }
    165 
    166 #if SK_SUPPORT_GPU
    167 
    168 GrTexture* SkImage::getTexture() const {
    169     return as_IB(this)->peekTexture();
    170 }
    171 
    172 bool SkImage::isTextureBacked() const { return SkToBool(as_IB(this)->getTexture()); }
    173 
    174 GrBackendObject SkImage::getTextureHandle(bool flushPendingGrContextIO) const {
    175     GrTexture* texture = as_IB(this)->getTexture();
    176     if (texture) {
    177         GrContext* context = texture->getContext();
    178         if (context) {
    179             if (flushPendingGrContextIO) {
    180                 context->prepareSurfaceForExternalIO(texture);
    181             }
    182         }
    183         return texture->getTextureHandle();
    184     }
    185     return 0;
    186 }
    187 
    188 #else
    189 
    190 GrTexture* SkImage::getTexture() const { return nullptr; }
    191 
    192 bool SkImage::isTextureBacked() const { return false; }
    193 
    194 GrBackendObject SkImage::getTextureHandle(bool) const { return 0; }
    195 
    196 #endif
    197 
    198 ///////////////////////////////////////////////////////////////////////////////
    199 
    200 static bool raster_canvas_supports(const SkImageInfo& info) {
    201     switch (info.colorType()) {
    202         case kN32_SkColorType:
    203             return kUnpremul_SkAlphaType != info.alphaType();
    204         case kRGB_565_SkColorType:
    205             return true;
    206         case kAlpha_8_SkColorType:
    207             return true;
    208         default:
    209             break;
    210     }
    211     return false;
    212 }
    213 
    214 SkImage_Base::SkImage_Base(int width, int height, uint32_t uniqueID)
    215     : INHERITED(width, height, uniqueID)
    216     , fAddedToCache(false)
    217 {}
    218 
    219 SkImage_Base::~SkImage_Base() {
    220     if (fAddedToCache.load()) {
    221         SkNotifyBitmapGenIDIsStale(this->uniqueID());
    222     }
    223 }
    224 
    225 bool SkImage_Base::onReadPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
    226                                 int srcX, int srcY, CachingHint) const {
    227     if (!raster_canvas_supports(dstInfo)) {
    228         return false;
    229     }
    230 
    231     SkBitmap bm;
    232     bm.installPixels(dstInfo, dstPixels, dstRowBytes);
    233     SkCanvas canvas(bm);
    234 
    235     SkPaint paint;
    236     paint.setXfermodeMode(SkXfermode::kSrc_Mode);
    237     canvas.drawImage(this, -SkIntToScalar(srcX), -SkIntToScalar(srcY), &paint);
    238 
    239     return true;
    240 }
    241 
    242 ///////////////////////////////////////////////////////////////////////////////////////////////////
    243 
    244 bool SkImage::peekPixels(SkPixmap* pmap) const {
    245     SkImageInfo info;
    246     size_t rowBytes;
    247     const void* pixels = this->peekPixels(&info, &rowBytes);
    248     if (pixels) {
    249         if (pmap) {
    250             pmap->reset(info, pixels, rowBytes);
    251         }
    252         return true;
    253     }
    254     return false;
    255 }
    256 
    257 bool SkImage::readPixels(const SkPixmap& pmap, int srcX, int srcY, CachingHint chint) const {
    258     return this->readPixels(pmap.info(), pmap.writable_addr(), pmap.rowBytes(), srcX, srcY, chint);
    259 }
    260 
    261 #if SK_SUPPORT_GPU
    262 #include "GrTextureToYUVPlanes.h"
    263 #endif
    264 
    265 #include "SkRGBAToYUV.h"
    266 
    267 bool SkImage::readYUV8Planes(const SkISize sizes[3], void* const planes[3],
    268                              const size_t rowBytes[3], SkYUVColorSpace colorSpace) const {
    269 #if SK_SUPPORT_GPU
    270     if (GrTexture* texture = as_IB(this)->peekTexture()) {
    271         if (GrTextureToYUVPlanes(texture, sizes, planes, rowBytes, colorSpace)) {
    272             return true;
    273         }
    274     }
    275 #endif
    276     return SkRGBAToYUV(this, sizes, planes, rowBytes, colorSpace);
    277 }
    278 
    279 ///////////////////////////////////////////////////////////////////////////////////////////////////
    280 
    281 SkImage* SkImage::NewFromBitmap(const SkBitmap& bm) {
    282     SkPixelRef* pr = bm.pixelRef();
    283     if (nullptr == pr) {
    284         return nullptr;
    285     }
    286 
    287 #if SK_SUPPORT_GPU
    288     if (GrTexture* tex = pr->getTexture()) {
    289         SkAutoTUnref<GrTexture> unrefCopy;
    290         if (!bm.isImmutable()) {
    291             tex = GrDeepCopyTexture(tex, SkBudgeted::kNo);
    292             if (nullptr == tex) {
    293                 return nullptr;
    294             }
    295             unrefCopy.reset(tex);
    296         }
    297         const SkImageInfo info = bm.info();
    298         return new SkImage_Gpu(info.width(), info.height(), bm.getGenerationID(), info.alphaType(),
    299                                tex, SkBudgeted::kNo);
    300     }
    301 #endif
    302 
    303     // This will check for immutable (share or copy)
    304     return SkNewImageFromRasterBitmap(bm);
    305 }
    306 
    307 bool SkImage::asLegacyBitmap(SkBitmap* bitmap, LegacyBitmapMode mode) const {
    308     return as_IB(this)->onAsLegacyBitmap(bitmap, mode);
    309 }
    310 
    311 bool SkImage_Base::onAsLegacyBitmap(SkBitmap* bitmap, LegacyBitmapMode mode) const {
    312     // As the base-class, all we can do is make a copy (regardless of mode).
    313     // Subclasses that want to be more optimal should override.
    314     SkImageInfo info = SkImageInfo::MakeN32(this->width(), this->height(),
    315                                     this->isOpaque() ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
    316     if (!bitmap->tryAllocPixels(info)) {
    317         return false;
    318     }
    319     if (!this->readPixels(bitmap->info(), bitmap->getPixels(), bitmap->rowBytes(), 0, 0)) {
    320         bitmap->reset();
    321         return false;
    322     }
    323 
    324     if (kRO_LegacyBitmapMode == mode) {
    325         bitmap->setImmutable();
    326     }
    327     return true;
    328 }
    329 
    330 SkImage* SkImage::NewFromPicture(const SkPicture* picture, const SkISize& dimensions,
    331                                  const SkMatrix* matrix, const SkPaint* paint) {
    332     if (!picture) {
    333         return nullptr;
    334     }
    335     return NewFromGenerator(SkImageGenerator::NewFromPicture(dimensions, picture, matrix, paint));
    336 }
    337 
    338 bool SkImage::isLazyGenerated() const {
    339     return as_IB(this)->onIsLazyGenerated();
    340 }
    341 
    342 //////////////////////////////////////////////////////////////////////////////////////
    343 
    344 #if !SK_SUPPORT_GPU
    345 
    346 SkImage* SkImage::NewFromTexture(GrContext*, const GrBackendTextureDesc&, SkAlphaType,
    347                                  TextureReleaseProc, ReleaseContext) {
    348     return nullptr;
    349 }
    350 
    351 SkImage* SkImage::NewFromAdoptedTexture(GrContext*, const GrBackendTextureDesc&, SkAlphaType) {
    352     return nullptr;
    353 }
    354 
    355 SkImage* SkImage::NewFromTextureCopy(GrContext*, const GrBackendTextureDesc&, SkAlphaType) {
    356     return nullptr;
    357 }
    358 
    359 SkImage* SkImage::newTextureImage(GrContext*) const {
    360     return nullptr;
    361 }
    362 
    363 #endif
    364