C++ SkAutoMalloc::reset方法代码示例

//.........这里部分代码省略.........
    */
    if (skiaSampleSize == 1 &&
        ((config == SkBitmap::kARGB_8888_Config &&
                cinfo->out_color_space == JCS_RGBA_8888) ||
        (config == SkBitmap::kRGB_565_Config &&
                cinfo->out_color_space == JCS_RGB_565)))
    {
        bitmap->setConfig(config, cinfo->output_width, height);
        bitmap->setIsOpaque(true);
        if (!this->allocPixelRef(bitmap, NULL)) {
            return return_false(*cinfo, *bitmap, "allocPixelRef");
        }
        SkAutoLockPixels alp(*bitmap);
        JSAMPLE* rowptr = (JSAMPLE*)bitmap->getPixels();
        INT32 const bpr = bitmap->rowBytes();
        int row_total_count = 0;

        while (row_total_count < height) {
            int row_count = jpeg_read_tile_scanline(cinfo,
                    index->index, &rowptr);
            // if row_count == 0, then we didn't get a scanline, so abort.
            // if we supported partial images, we might return true in this case
            if (0 == row_count) {
                return return_false(*cinfo, *bitmap, "read_scanlines");
            }
            if (this->shouldCancelDecode()) {
                return return_false(*cinfo, *bitmap, "shouldCancelDecode");
            }
            row_total_count += row_count;
            rowptr += bpr;
        }
        cropBitmap(bm, bitmap, actualSampleSize, oriStartX, oriStartY,
                   oriWidth, oriHeight, startX, startY);
        return true;
    }
#endif
    // check for supported formats
    SkScaledBitmapSampler::SrcConfig sc;
    if (3 == cinfo->out_color_components && JCS_RGB == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kRGB;
#ifdef ANDROID_RGB
    } else if (JCS_RGBA_8888 == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kRGBX;
    } else if (JCS_RGB_565 == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kRGB_565;
#endif
    } else if (1 == cinfo->out_color_components &&
               JCS_GRAYSCALE == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kGray;
    } else {
        return return_false(*cinfo, *bm, "jpeg colorspace");
    }

    SkScaledBitmapSampler sampler(width, height, skiaSampleSize);

    bitmap->setConfig(config, sampler.scaledWidth(), sampler.scaledHeight());
    bitmap->setIsOpaque(true);

    if (!this->allocPixelRef(bitmap, NULL)) {
        return return_false(*cinfo, *bitmap, "allocPixelRef");
    }

    SkAutoLockPixels alp(*bitmap);
    if (!sampler.begin(bitmap, sc, this->getDitherImage())) {
        return return_false(*cinfo, *bitmap, "sampler.begin");
    }

    uint8_t* srcRow = (uint8_t*)srcStorage.reset(width * 4);

    //  Possibly skip initial rows [sampler.srcY0]
    if (!skip_src_rows_tile(cinfo, index->index, srcRow, sampler.srcY0())) {
        return return_false(*cinfo, *bitmap, "skip rows");
    }

    // now loop through scanlines until y == bitmap->height() - 1
    for (int y = 0;; y++) {
        JSAMPLE* rowptr = (JSAMPLE*)srcRow;
        int row_count = jpeg_read_tile_scanline(cinfo, index->index, &rowptr);
        if (0 == row_count) {
            return return_false(*cinfo, *bitmap, "read_scanlines");
        }
        if (this->shouldCancelDecode()) {
            return return_false(*cinfo, *bitmap, "shouldCancelDecode");
        }

        sampler.next(srcRow);
        if (bitmap->height() - 1 == y) {
            // we're done
            break;
        }

        if (!skip_src_rows_tile(cinfo, index->index, srcRow,
                                sampler.srcDY() - 1)) {
            return return_false(*cinfo, *bitmap, "skip rows");
        }
    }
    cropBitmap(bm, bitmap, actualSampleSize, oriStartX, oriStartY,
               oriWidth, oriHeight, startX, startY);
    return true;
}

//.........这里部分代码省略.........
        if (reuseBitmap) {
            bm->notifyPixelsChanged();
        }
        jpeg_finish_decompress(&cinfo);
        return true;
    }
#endif
    
    // check for supported formats
    SkScaledBitmapSampler::SrcConfig sc;
    if (3 == cinfo.out_color_components && JCS_RGB == cinfo.out_color_space) {
        sc = SkScaledBitmapSampler::kRGB;
#ifdef ANDROID_RGB
    } else if (JCS_RGBA_8888 == cinfo.out_color_space) {
        sc = SkScaledBitmapSampler::kRGBX;
    } else if (JCS_RGB_565 == cinfo.out_color_space) {
        sc = SkScaledBitmapSampler::kRGB_565;
#endif
    } else if (1 == cinfo.out_color_components &&
               JCS_GRAYSCALE == cinfo.out_color_space) {
        sc = SkScaledBitmapSampler::kGray;
    } else {
        return return_false(cinfo, *bm, "jpeg colorspace");
    }

    SkScaledBitmapSampler sampler(cinfo.output_width, cinfo.output_height,
                                  sampleSize);

    bm->lockPixels();
    JSAMPLE* rowptr = (JSAMPLE*)bm->getPixels();
    bool reuseBitmap = (rowptr != NULL);
    bm->unlockPixels();
    if (reuseBitmap && (sampler.scaledWidth() != bm->width() ||
            sampler.scaledHeight() != bm->height())) {
        // Dimensions must match
        return false;
    }

    if (!reuseBitmap) {
        bm->setConfig(config, sampler.scaledWidth(), sampler.scaledHeight());
        // jpegs are always opaque (i.e. have no per-pixel alpha)
        bm->setIsOpaque(true);

        if (SkImageDecoder::kDecodeBounds_Mode == mode) {
            return true;
        }
        if (!this->allocPixelRef(bm, NULL)) {
            return return_false(cinfo, *bm, "allocPixelRef");
        }
    } else if (SkImageDecoder::kDecodeBounds_Mode == mode) {
        return true;
    }

    SkAutoLockPixels alp(*bm);                          
    if (!sampler.begin(bm, sc, this->getDitherImage())) {
        return return_false(cinfo, *bm, "sampler.begin");
    }

    uint8_t* srcRow = (uint8_t*)srcStorage.reset(cinfo.output_width * 4);

    //  Possibly skip initial rows [sampler.srcY0]
    if (!skip_src_rows(&cinfo, srcRow, sampler.srcY0())) {
        return return_false(cinfo, *bm, "skip rows");
    }

    // now loop through scanlines until y == bm->height() - 1
    for (int y = 0;; y++) {
        JSAMPLE* rowptr = (JSAMPLE*)srcRow;
        int row_count = jpeg_read_scanlines(&cinfo, &rowptr, 1);
        if (0 == row_count) {
            return return_false(cinfo, *bm, "read_scanlines");
        }
        if (this->shouldCancelDecode()) {
            return return_false(cinfo, *bm, "shouldCancelDecode");
        }
        
        sampler.next(srcRow);
        if (bm->height() - 1 == y) {
            // we're done
            break;
        }

        if (!skip_src_rows(&cinfo, srcRow, sampler.srcDY() - 1)) {
            return return_false(cinfo, *bm, "skip rows");
        }
    }

    // we formally skip the rest, so we don't get a complaint from libjpeg
    if (!skip_src_rows(&cinfo, srcRow,
                       cinfo.output_height - cinfo.output_scanline)) {
        return return_false(cinfo, *bm, "skip rows");
    }
    if (reuseBitmap) {
        bm->notifyPixelsChanged();
    }
    jpeg_finish_decompress(&cinfo);

//    SkDebugf("------------------- bm2 size %d [%d %d] %d\n", bm->getSize(), bm->width(), bm->height(), bm->config());
    return true;
}

static GrTexture* load_yuv_texture(GrContext* ctx, const GrUniqueKey& optionalKey,
                                   const SkBitmap& bm, const GrSurfaceDesc& desc) {
    // Subsets are not supported, the whole pixelRef is loaded when using YUV decoding
    SkPixelRef* pixelRef = bm.pixelRef();
    if ((NULL == pixelRef) || 
        (pixelRef->info().width()  != bm.info().width()) ||
        (pixelRef->info().height() != bm.info().height())) {
        return NULL;
    }

    const bool useCache = optionalKey.isValid();
    SkYUVPlanesCache::Info yuvInfo;
    SkAutoTUnref<SkCachedData> cachedData;
    SkAutoMalloc storage;
    if (useCache) {
        cachedData.reset(SkYUVPlanesCache::FindAndRef(pixelRef->getGenerationID(), &yuvInfo));
    }

    void* planes[3];
    if (cachedData.get()) {
        planes[0] = (void*)cachedData->data();
        planes[1] = (uint8_t*)planes[0] + yuvInfo.fSizeInMemory[0];
        planes[2] = (uint8_t*)planes[1] + yuvInfo.fSizeInMemory[1];
    } else {
        // Fetch yuv plane sizes for memory allocation. Here, width and height can be
        // rounded up to JPEG block size and be larger than the image's width and height.
        if (!pixelRef->getYUV8Planes(yuvInfo.fSize, NULL, NULL, NULL)) {
            return NULL;
        }

        // Allocate the memory for YUV
        size_t totalSize(0);
        for (int i = 0; i < 3; ++i) {
            yuvInfo.fRowBytes[i] = yuvInfo.fSize[i].fWidth;
            yuvInfo.fSizeInMemory[i] = yuvInfo.fRowBytes[i] * yuvInfo.fSize[i].fHeight;
            totalSize += yuvInfo.fSizeInMemory[i];
        }
        if (useCache) {
            cachedData.reset(SkResourceCache::NewCachedData(totalSize));
            planes[0] = cachedData->writable_data();
        } else {
            storage.reset(totalSize);
            planes[0] = storage.get();
        }
        planes[1] = (uint8_t*)planes[0] + yuvInfo.fSizeInMemory[0];
        planes[2] = (uint8_t*)planes[1] + yuvInfo.fSizeInMemory[1];

        // Get the YUV planes and update plane sizes to actual image size
        if (!pixelRef->getYUV8Planes(yuvInfo.fSize, planes, yuvInfo.fRowBytes,
                                     &yuvInfo.fColorSpace)) {
            return NULL;
        }

        if (useCache) {
            // Decoding is done, cache the resulting YUV planes
            SkYUVPlanesCache::Add(pixelRef->getGenerationID(), cachedData, &yuvInfo);
        }
    }

    GrSurfaceDesc yuvDesc;
    yuvDesc.fConfig = kAlpha_8_GrPixelConfig;
    SkAutoTUnref<GrTexture> yuvTextures[3];
    for (int i = 0; i < 3; ++i) {
        yuvDesc.fWidth  = yuvInfo.fSize[i].fWidth;
        yuvDesc.fHeight = yuvInfo.fSize[i].fHeight;
        bool needsExactTexture =
            (yuvDesc.fWidth  != yuvInfo.fSize[0].fWidth) ||
            (yuvDesc.fHeight != yuvInfo.fSize[0].fHeight);
        if (needsExactTexture) {
            yuvTextures[i].reset(ctx->textureProvider()->createTexture(yuvDesc, true));
        } else {
            yuvTextures[i].reset(ctx->textureProvider()->createApproxTexture(yuvDesc));
        }
        if (!yuvTextures[i] ||
            !yuvTextures[i]->writePixels(0, 0, yuvDesc.fWidth, yuvDesc.fHeight,
                                         yuvDesc.fConfig, planes[i], yuvInfo.fRowBytes[i])) {
            return NULL;
        }
    }

    GrSurfaceDesc rtDesc = desc;
    rtDesc.fFlags = rtDesc.fFlags | kRenderTarget_GrSurfaceFlag;

    GrTexture* result = create_texture_for_bmp(ctx, optionalKey, rtDesc, pixelRef, NULL, 0);
    if (!result) {
        return NULL;
    }

    GrRenderTarget* renderTarget = result->asRenderTarget();
    SkASSERT(renderTarget);

    GrPaint paint;
    SkAutoTUnref<GrFragmentProcessor>
        yuvToRgbProcessor(GrYUVtoRGBEffect::Create(paint.getProcessorDataManager(), yuvTextures[0],
                                                   yuvTextures[1], yuvTextures[2],
                                                   yuvInfo.fSize, yuvInfo.fColorSpace));
    paint.addColorProcessor(yuvToRgbProcessor);
    SkRect r = SkRect::MakeWH(SkIntToScalar(yuvInfo.fSize[0].fWidth),
                              SkIntToScalar(yuvInfo.fSize[0].fHeight));

//.........这里部分代码省略.........

void SkScalerContext::getImage(const SkGlyph& origGlyph) {
    const SkGlyph*  glyph = &origGlyph;
    SkGlyph         tmpGlyph;

    // in case we need to call generateImage on a mask-format that is different
    // (i.e. larger) than what our caller allocated by looking at origGlyph.
    SkAutoMalloc tmpGlyphImageStorage;

    // If we are going to draw-from-path, then we cannot generate color, since
    // the path only makes a mask. This case should have been caught up in
    // generateMetrics().
    SkASSERT(!fGenerateImageFromPath ||
             SkMask::kARGB32_Format != origGlyph.fMaskFormat);

    if (fMaskFilter) {   // restore the prefilter bounds
        tmpGlyph.initGlyphIdFrom(origGlyph);

        // need the original bounds, sans our maskfilter
        SkMaskFilter* mf = fMaskFilter;
        fMaskFilter = nullptr;             // temp disable
        this->getMetrics(&tmpGlyph);
        fMaskFilter = mf;               // restore

        // we need the prefilter bounds to be <= filter bounds
        SkASSERT(tmpGlyph.fWidth <= origGlyph.fWidth);
        SkASSERT(tmpGlyph.fHeight <= origGlyph.fHeight);

        if (tmpGlyph.fMaskFormat == origGlyph.fMaskFormat) {
            tmpGlyph.fImage = origGlyph.fImage;
        } else {
            tmpGlyphImageStorage.reset(tmpGlyph.computeImageSize());
            tmpGlyph.fImage = tmpGlyphImageStorage.get();
        }
        glyph = &tmpGlyph;
    }

    if (fGenerateImageFromPath) {
        SkPath      devPath, fillPath;
        SkMatrix    fillToDevMatrix;
        SkMask      mask;

        this->internalGetPath(*glyph, &fillPath, &devPath, &fillToDevMatrix);
        glyph->toMask(&mask);

        if (fRasterizer) {
            mask.fFormat = SkMask::kA8_Format;
            sk_bzero(glyph->fImage, mask.computeImageSize());

            if (!fRasterizer->rasterize(fillPath, fillToDevMatrix, nullptr,
                                        fMaskFilter, &mask,
                                        SkMask::kJustRenderImage_CreateMode)) {
                return;
            }
            if (fPreBlend.isApplicable()) {
                applyLUTToA8Mask(mask, fPreBlend.fG);
            }
        } else {
            SkASSERT(SkMask::kARGB32_Format != mask.fFormat);
            generateMask(mask, devPath, fPreBlend);
        }
    } else {
        generateImage(*glyph);
    }

    if (fMaskFilter) {
        SkMask      srcM, dstM;
        SkMatrix    matrix;

        // the src glyph image shouldn't be 3D
        SkASSERT(SkMask::k3D_Format != glyph->fMaskFormat);

        SkAutoSMalloc<32*32> a8storage;
        glyph->toMask(&srcM);
        if (SkMask::kARGB32_Format == srcM.fFormat) {
            // now we need to extract the alpha-channel from the glyph's image
            // and copy it into a temp buffer, and then point srcM at that temp.
            srcM.fFormat = SkMask::kA8_Format;
            srcM.fRowBytes = SkAlign4(srcM.fBounds.width());
            size_t size = srcM.computeImageSize();
            a8storage.reset(size);
            srcM.fImage = (uint8_t*)a8storage.get();
            extract_alpha(srcM,
                          (const SkPMColor*)glyph->fImage, glyph->rowBytes());
        }

        fRec.getMatrixFrom2x2(&matrix);

        if (fMaskFilter->filterMask(&dstM, srcM, matrix, nullptr)) {
            int width = SkFastMin32(origGlyph.fWidth, dstM.fBounds.width());
            int height = SkFastMin32(origGlyph.fHeight, dstM.fBounds.height());
            int dstRB = origGlyph.rowBytes();
            int srcRB = dstM.fRowBytes;

            const uint8_t* src = (const uint8_t*)dstM.fImage;
            uint8_t* dst = (uint8_t*)origGlyph.fImage;

            if (SkMask::k3D_Format == dstM.fFormat) {
                // we have to copy 3 times as much
                height *= 3;
            }
//.........这里部分代码省略.........

//.........这里部分代码省略.........
            if (this->shouldCancelDecode()) {
                return return_false(*cinfo, *bitmap, "shouldCancelDecode");
            }
            row_total_count += row_count;
            rowptr += bpr;
        }

        if (swapOnly) {
            bm->swap(*bitmap);
        } else {
            cropBitmap(bm, bitmap, actualSampleSize, region.x(), region.y(),
                       region.width(), region.height(), startX, startY);
        }
        return true;
    }
#endif
    // check for supported formats
    SkScaledBitmapSampler::SrcConfig sc;
    if (3 == cinfo->out_color_components && JCS_RGB == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kRGB;
#ifdef ANDROID_RGB
    } else if (JCS_RGBA_8888 == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kRGBX;
    } else if (JCS_RGB_565 == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kRGB_565;
#endif
    } else if (1 == cinfo->out_color_components &&
               JCS_GRAYSCALE == cinfo->out_color_space) {
        sc = SkScaledBitmapSampler::kGray;
    } else {
        return return_false(*cinfo, *bm, "jpeg colorspace");
    }

    SkScaledBitmapSampler sampler(width, height, skiaSampleSize);

    bitmap->setConfig(config, sampler.scaledWidth(), sampler.scaledHeight());
    bitmap->setIsOpaque(true);

    // Check ahead of time if the swap(dest, src) is possible or not.
    // If yes, then we will stick to AllocPixelRef since it's cheaper with the
    // swap happening. If no, then we will use alloc to allocate pixels to
    // prevent garbage collection.
    int w = rect.width() / actualSampleSize;
    int h = rect.height() / actualSampleSize;
    bool swapOnly = (rect == region) && bm->isNull() &&
                    (w == bitmap->width()) && (h == bitmap->height()) &&
                    ((startX - rect.x()) / actualSampleSize == 0) &&
                    ((startY - rect.y()) / actualSampleSize == 0);
    if (swapOnly) {
        if (!this->allocPixelRef(bitmap, NULL)) {
            return return_false(*cinfo, *bitmap, "allocPixelRef");
        }
    } else {
        if (!bitmap->allocPixels()) {
            return return_false(*cinfo, *bitmap, "allocPixels");
        }
    }

    SkAutoLockPixels alp(*bitmap);
    if (!sampler.begin(bitmap, sc, this->getDitherImage())) {
        return return_false(*cinfo, *bitmap, "sampler.begin");
    }

    uint8_t* srcRow = (uint8_t*)srcStorage.reset(width * 4);

    //  Possibly skip initial rows [sampler.srcY0]
    if (!skip_src_rows_tile(cinfo, index->index, srcRow, sampler.srcY0())) {
        return return_false(*cinfo, *bitmap, "skip rows");
    }

    // now loop through scanlines until y == bitmap->height() - 1
    for (int y = 0;; y++) {
        JSAMPLE* rowptr = (JSAMPLE*)srcRow;
        int row_count = jpeg_read_tile_scanline(cinfo, index->index, &rowptr);
        if (0 == row_count) {
            return return_false(*cinfo, *bitmap, "read_scanlines");
        }
        if (this->shouldCancelDecode()) {
            return return_false(*cinfo, *bitmap, "shouldCancelDecode");
        }

        sampler.next(srcRow);
        if (bitmap->height() - 1 == y) {
            // we're done
            break;
        }

        if (!skip_src_rows_tile(cinfo, index->index, srcRow,
                                sampler.srcDY() - 1)) {
            return return_false(*cinfo, *bitmap, "skip rows");
        }
    }
    if (swapOnly) {
        bm->swap(*bitmap);
    } else {
        cropBitmap(bm, bitmap, actualSampleSize, region.x(), region.y(),
                   region.width(), region.height(), startX, startY);
    }
    return true;
}