C++ SkPixmap::rowBytes方法代码示例

bool SkBitmapScaler::Resize(const SkPixmap& result, const SkPixmap& source, ResizeMethod method) {
    if (!valid_for_resize(source, result.width(), result.height())) {
        return false;
    }
    if (!result.addr() || result.colorType() != source.colorType()) {
        return false;
    }

    SkConvolutionProcs convolveProcs= { 0, nullptr, nullptr, nullptr, nullptr };
    PlatformConvolutionProcs(&convolveProcs);

    SkRect destSubset = SkRect::MakeIWH(result.width(), result.height());

    SkResizeFilter filter(method, source.width(), source.height(),
                          result.width(), result.height(), destSubset, convolveProcs);

    // Get a subset encompassing this touched area. We construct the
    // offsets and row strides such that it looks like a new bitmap, while
    // referring to the old data.
    const uint8_t* sourceSubset = reinterpret_cast<const uint8_t*>(source.addr());

    return BGRAConvolve2D(sourceSubset, static_cast<int>(source.rowBytes()),
                          !source.isOpaque(), filter.xFilter(), filter.yFilter(),
                          static_cast<int>(result.rowBytes()),
                          static_cast<unsigned char*>(result.writable_addr()),
                          convolveProcs, true);
}

SkLinearBitmapPipeline::SkLinearBitmapPipeline(
    const SkLinearBitmapPipeline& pipeline,
    const SkPixmap& srcPixmap,
    SkXfermode::Mode mode,
    const SkImageInfo& dstInfo)
{
    SkASSERT(mode == SkXfermode::kSrc_Mode || mode == SkXfermode::kSrcOver_Mode);
    SkASSERT(srcPixmap.info().colorType() == dstInfo.colorType()
             && srcPixmap.info().colorType() == kRGBA_8888_SkColorType);

    if (mode == SkXfermode::kSrc_Mode) {
        fSampleStage.initSink<RGBA8888UnitRepeatSrc>(
            srcPixmap.writable_addr32(0, 0), srcPixmap.rowBytes() / 4);
        fLastStage = fSampleStage.getInterface<DestinationInterface, RGBA8888UnitRepeatSrc>();
    } else {
        fSampleStage.initSink<RGBA8888UnitRepeatSrcOver>(
            srcPixmap.writable_addr32(0, 0), srcPixmap.rowBytes() / 4);
        fLastStage = fSampleStage.getInterface<DestinationInterface, RGBA8888UnitRepeatSrcOver>();
    }

    auto sampleStage = fSampleStage.get();
    auto tilerStage = pipeline.fTileStage.cloneStageTo(sampleStage, &fTileStage);
    tilerStage = (tilerStage != nullptr) ? tilerStage : sampleStage;
    auto matrixStage = pipeline.fMatrixStage.cloneStageTo(tilerStage, &fMatrixStage);
    matrixStage = (matrixStage != nullptr) ? matrixStage : tilerStage;
    fFirstStage = matrixStage;
}

void SkDrawCommandGeometryWidget::paintEvent(QPaintEvent* event) {
    this->QFrame::paintEvent(event);

    if (!fSurface) {
        return;
    }

    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing);

    SkPixmap pixmap;

    if (fSurface->peekPixels(&pixmap)) {
        SkASSERT(pixmap.width() > 0);
        SkASSERT(pixmap.height() > 0);

        QRectF resultRect;
        if (this->width() < this->height()) {
            float ratio = this->width() / pixmap.width();
            resultRect = QRectF(0, 0, this->width(), ratio * pixmap.height());
        } else {
            float ratio = this->height() / pixmap.height();
            resultRect = QRectF(0, 0, ratio * pixmap.width(), this->height());
        }

        resultRect.moveCenter(this->contentsRect().center());

        QImage image(reinterpret_cast<const uchar*>(pixmap.addr()),
                     pixmap.width(),
                     pixmap.height(),
                     pixmap.rowBytes(),
                     QImage::Format_ARGB32_Premultiplied);
        painter.drawImage(resultRect, image);
    }
}

    bool onGetROPixels(SkBitmap* dst) const override {
        const auto desc = SkBitmapCacheDesc::Make(this->uniqueID(), this->width(), this->height());
        if (SkBitmapCache::Find(desc, dst)) {
            SkASSERT(dst->getGenerationID() == this->uniqueID());
            SkASSERT(dst->isImmutable());
            SkASSERT(dst->getPixels());
            return true;
        }

        SkPixmap pmap;
        SkImageInfo info = SkImageInfo::MakeN32(this->width(), this->height(),
                                                this->alphaType(), fColorSpace);
        auto rec = SkBitmapCache::Alloc(desc, info, &pmap);
        if (!rec) {
            return false;
        }
        sk_sp<SkColorSpace> colorSpace;
        if (GrPixelConfigIsSRGB(fTextureProxy->config())) {
            colorSpace = SkColorSpace::MakeSRGB();
        }
        sk_sp<GrSurfaceContext> sContext = fContext->contextPriv().makeWrappedSurfaceContext(
                fTextureProxy, std::move(colorSpace));
        if (!sContext) {
            return false;
        }

        if (!sContext->readPixels(info, pmap.writable_addr(), pmap.rowBytes(), 0, 0)) {
            return false;
        }

        SkBitmapCache::Add(std::move(rec), dst);
        fAddedRasterVersionToCache.store(true);
        return true;
    }

bool SkPixmap::scalePixels(const SkPixmap& dst, SkFilterQuality quality) const {
    // Can't do anthing with empty src or dst
    if (this->width() <= 0 || this->height() <= 0 || dst.width() <= 0 || dst.height() <= 0) {
        return false;
    }

    // no scaling involved?
    if (dst.width() == this->width() && dst.height() == this->height()) {
        return this->readPixels(dst);
    }

    SkBitmap bitmap;
    if (!bitmap.installPixels(*this)) {
        return false;
    }
    bitmap.setIsVolatile(true); // so we don't try to cache it

    SkAutoTUnref<SkSurface> surface(SkSurface::NewRasterDirect(dst.info(), dst.writable_addr(),
                                                               dst.rowBytes()));
    if (!surface) {
        return false;
    }

    SkPaint paint;
    paint.setFilterQuality(quality);
    paint.setXfermodeMode(SkXfermode::kSrc_Mode);
    surface->getCanvas()->drawBitmapRect(bitmap, SkRect::MakeIWH(dst.width(), dst.height()),
                                         &paint);
    return true;
}

 SkSpecialImage_Raster(const SkIRect& subset,
                       const SkPixmap& pixmap,
                       RasterReleaseProc releaseProc,
                       ReleaseContext context,
                       const SkSurfaceProps* props)
     : INHERITED(subset, kNeedNewImageUniqueID_SpecialImage, props) {
     fBitmap.installPixels(pixmap.info(), pixmap.writable_addr(),
                           pixmap.rowBytes(), pixmap.ctable(),
                           releaseProc, context);
 }

static void test_newraster(skiatest::Reporter* reporter) {
    SkImageInfo info = SkImageInfo::MakeN32Premul(10, 10);
    const size_t minRowBytes = info.minRowBytes();
    const size_t size = info.getSafeSize(minRowBytes);
    SkAutoTMalloc<SkPMColor> storage(size);
    SkPMColor* baseAddr = storage.get();
    sk_bzero(baseAddr, size);

    std::unique_ptr<SkCanvas> canvas = SkCanvas::MakeRasterDirect(info, baseAddr, minRowBytes);
    REPORTER_ASSERT(reporter, canvas);

    SkPixmap pmap;
    const SkPMColor* addr = canvas->peekPixels(&pmap) ? pmap.addr32() : nullptr;
    REPORTER_ASSERT(reporter, addr);
    REPORTER_ASSERT(reporter, info == pmap.info());
    REPORTER_ASSERT(reporter, minRowBytes == pmap.rowBytes());
    for (int y = 0; y < info.height(); ++y) {
        for (int x = 0; x < info.width(); ++x) {
            REPORTER_ASSERT(reporter, 0 == addr[x]);
        }
        addr = (const SkPMColor*)((const char*)addr + pmap.rowBytes());
    }

    // now try a deliberately bad info
    info = info.makeWH(-1, info.height());
    REPORTER_ASSERT(reporter, nullptr == SkCanvas::MakeRasterDirect(info, baseAddr, minRowBytes));

    // too big
    info = info.makeWH(1 << 30, 1 << 30);
    REPORTER_ASSERT(reporter, nullptr == SkCanvas::MakeRasterDirect(info, baseAddr, minRowBytes));

    // not a valid pixel type
    info = SkImageInfo::Make(10, 10, kUnknown_SkColorType, info.alphaType());
    REPORTER_ASSERT(reporter, nullptr == SkCanvas::MakeRasterDirect(info, baseAddr, minRowBytes));

    // We should succeed with a zero-sized valid info
    info = SkImageInfo::MakeN32Premul(0, 0);
    canvas = SkCanvas::MakeRasterDirect(info, baseAddr, minRowBytes);
    REPORTER_ASSERT(reporter, canvas);
}

const void* SkSurface::peekPixels(SkImageInfo* info, size_t* rowBytes) {
    SkPixmap pm;
    if (this->peekPixels(&pm)) {
        if (info) {
            *info = pm.info();
        }
        if (rowBytes) {
            *rowBytes = pm.rowBytes();
        }
        return pm.addr();
    }
    return nullptr;
}

    size_t getSize() const override {
#if SK_SUPPORT_GPU
        if (GrTexture* texture = as_IB(fImage.get())->peekTexture()) {
            return texture->gpuMemorySize();
        } else
#endif
        {
            SkPixmap pm;
            if (fImage->peekPixels(&pm)) {
                return pm.height() * pm.rowBytes();
            }
        }
        return 0;
    }

bool SkBitmapScaler::Resize(SkBitmap* resultPtr, const SkPixmap& source, ResizeMethod method,
                            int destWidth, int destHeight, SkBitmap::Allocator* allocator) {
    if (nullptr == source.addr() || source.colorType() != kN32_SkColorType ||
        source.width() < 1 || source.height() < 1)
    {
        return false;
    }

    if (destWidth < 1 || destHeight < 1) {
        return false;
    }

    SkConvolutionProcs convolveProcs= { 0, nullptr, nullptr, nullptr, nullptr };
    PlatformConvolutionProcs(&convolveProcs);

    SkRect destSubset = SkRect::MakeIWH(destWidth, destHeight);

    SkResizeFilter filter(method, source.width(), source.height(),
                        destWidth, destHeight, destSubset, convolveProcs);

    // Get a subset encompassing this touched area. We construct the
    // offsets and row strides such that it looks like a new bitmap, while
    // referring to the old data.
    const uint8_t* sourceSubset = reinterpret_cast<const uint8_t*>(source.addr());

    // Convolve into the result.
    SkBitmap result;
    result.setInfo(SkImageInfo::MakeN32(SkScalarCeilToInt(destSubset.width()),
                                      SkScalarCeilToInt(destSubset.height()),
                                      source.alphaType()));
    result.allocPixels(allocator, nullptr);
    if (!result.readyToDraw()) {
      return false;
    }

    if (!BGRAConvolve2D(sourceSubset, static_cast<int>(source.rowBytes()),
                        !source.isOpaque(), filter.xFilter(), filter.yFilter(),
                        static_cast<int>(result.rowBytes()),
                        static_cast<unsigned char*>(result.getPixels()),
                        convolveProcs, true)) {
        return false;
    }

    *resultPtr = result;
    resultPtr->lockPixels();
    SkASSERT(resultPtr->getPixels());
    return true;
}

bool SkImage_Gpu::getROPixels(SkBitmap* dst, SkColorSpace* dstColorSpace, CachingHint chint) const {
    const auto desc = SkBitmapCacheDesc::Make(this);
    if (SkBitmapCache::Find(desc, dst)) {
        SkASSERT(dst->getGenerationID() == this->uniqueID());
        SkASSERT(dst->isImmutable());
        SkASSERT(dst->getPixels());
        return true;
    }

    SkImageInfo ii = make_info(this->width(), this->height(), this->alphaType(),
                               sk_ref_sp(dstColorSpace));
    SkBitmapCache::RecPtr rec = nullptr;
    SkPixmap pmap;
    if (kAllow_CachingHint == chint) {
        rec = SkBitmapCache::Alloc(desc, ii, &pmap);
        if (!rec) {
            return false;
        }
    } else {
        if (!dst->tryAllocPixels(ii)) {
            return false;
        }
    }

    sk_sp<GrSurfaceContext> sContext = fContext->contextPriv().makeWrappedSurfaceContext(
                                                                                    fProxy,
                                                                                    fColorSpace);
    if (!sContext) {
        return false;
    }

    if (!sContext->readPixels(pmap.info(), pmap.writable_addr(), pmap.rowBytes(), 0, 0)) {
        return false;
    }

    if (rec) {
        SkBitmapCache::Add(std::move(rec), dst);
        fAddedRasterVersionToCache.store(true);
    }
    return true;
}

bool
SourceSurfaceSkia::InitFromImage(sk_sp<SkImage> aImage,
                                 SurfaceFormat aFormat,
                                 DrawTargetSkia* aOwner)
{
  if (!aImage) {
    return false;
  }

  mSize = IntSize(aImage->width(), aImage->height());

  // For the raster image case, we want to use the format and stride
  // information that the underlying raster image is using, which is
  // reliable.
  // For the GPU case (for which peekPixels is false), we can't easily
  // figure this information out. It is better to report the originally
  // intended format and stride that we will convert to if this GPU
  // image is ever read back into a raster image.
  SkPixmap pixmap;
  if (aImage->peekPixels(&pixmap)) {
    mFormat =
      aFormat != SurfaceFormat::UNKNOWN ?
        aFormat :
        SkiaColorTypeToGfxFormat(pixmap.colorType(), pixmap.alphaType());
    mStride = pixmap.rowBytes();
  } else if (aFormat != SurfaceFormat::UNKNOWN) {
    mFormat = aFormat;
    SkImageInfo info = MakeSkiaImageInfo(mSize, mFormat);
    mStride = SkAlign4(info.minRowBytes());
  } else {
    return false;
  }

  mImage = aImage;

  if (aOwner) {
    mDrawTarget = aOwner;
  }

  return true;
}

static void SkARGB32_Blit32(const SkPixmap& device, const SkMask& mask,
                            const SkIRect& clip, SkPMColor srcColor) {
    U8CPU alpha = SkGetPackedA32(srcColor);
    unsigned flags = SkBlitRow::kSrcPixelAlpha_Flag32;
    if (alpha != 255) {
        flags |= SkBlitRow::kGlobalAlpha_Flag32;
    }
    SkBlitRow::Proc32 proc = SkBlitRow::Factory32(flags);

    int x = clip.fLeft;
    int y = clip.fTop;
    int width = clip.width();
    int height = clip.height();

    SkPMColor* dstRow = device.writable_addr32(x, y);
    const SkPMColor* srcRow = reinterpret_cast<const SkPMColor*>(mask.getAddr8(x, y));

    do {
        proc(dstRow, srcRow, width, alpha);
        dstRow = (SkPMColor*)((char*)dstRow + device.rowBytes());
        srcRow = (const SkPMColor*)((const char*)srcRow + mask.fRowBytes);
    } while (--height != 0);
}

static void test_peekpixels(skiatest::Reporter* reporter) {
    const SkImageInfo info = SkImageInfo::MakeN32Premul(10, 10);

    SkPixmap pmap;
    SkBitmap bm;

    // empty should return false
    REPORTER_ASSERT(reporter, !bm.peekPixels(nullptr));
    REPORTER_ASSERT(reporter, !bm.peekPixels(&pmap));

    // no pixels should return false
    bm.setInfo(SkImageInfo::MakeN32Premul(10, 10));
    REPORTER_ASSERT(reporter, !bm.peekPixels(nullptr));
    REPORTER_ASSERT(reporter, !bm.peekPixels(&pmap));

    // real pixels should return true
    bm.allocPixels(info);
    REPORTER_ASSERT(reporter, bm.peekPixels(nullptr));
    REPORTER_ASSERT(reporter, bm.peekPixels(&pmap));
    REPORTER_ASSERT(reporter, pmap.info() == bm.info());
    REPORTER_ASSERT(reporter, pmap.addr() == bm.getPixels());
    REPORTER_ASSERT(reporter, pmap.rowBytes() == bm.rowBytes());
}

SkCanvasState* SkCanvasStateUtils::CaptureCanvasState(SkCanvas* canvas) {
    SkASSERT(canvas);

    // Check the clip can be decomposed into rectangles (i.e. no soft clips).
    ClipValidator validator;
    canvas->replayClips(&validator);
    if (validator.failed()) {
        SkErrorInternals::SetError(kInvalidOperation_SkError,
                "CaptureCanvasState does not support canvases with antialiased clips.\n");
        return nullptr;
    }

    SkAutoTDelete<SkCanvasState_v1> canvasState(new SkCanvasState_v1(canvas));

    // decompose the total matrix and clip
    setup_MC_state(&canvasState->mcState, canvas->getTotalMatrix(),
                   canvas->internal_private_getTotalClip());

    /*
     * decompose the layers
     *
     * storage is allocated on the stack for the first 3 layers. It is common in
     * some view systems (e.g. Android) that a few non-clipped layers are present
     * and we will not need to malloc any additional memory in those cases.
     */
    SkSWriter32<3*sizeof(SkCanvasLayerState)> layerWriter;
    int layerCount = 0;
    for (SkCanvas::LayerIter layer(canvas); !layer.done(); layer.next()) {

        // we currently only work for bitmap backed devices
        SkPixmap pmap;
        if (!layer.device()->accessPixels(&pmap) || 0 == pmap.width() || 0 == pmap.height()) {
            return nullptr;
        }

        SkCanvasLayerState* layerState =
                (SkCanvasLayerState*) layerWriter.reserve(sizeof(SkCanvasLayerState));
        layerState->type = kRaster_CanvasBackend;
        layerState->x = layer.x();
        layerState->y = layer.y();
        layerState->width = pmap.width();
        layerState->height = pmap.height();

        switch (pmap.colorType()) {
            case kN32_SkColorType:
                layerState->raster.config = kARGB_8888_RasterConfig;
                break;
            case kRGB_565_SkColorType:
                layerState->raster.config = kRGB_565_RasterConfig;
                break;
            default:
                return nullptr;
        }
        layerState->raster.rowBytes = pmap.rowBytes();
        layerState->raster.pixels = pmap.writable_addr();

        setup_MC_state(&layerState->mcState, layer.matrix(), layer.clip().bwRgn());
        layerCount++;
    }

    // allocate memory for the layers and then and copy them to the struct
    SkASSERT(layerWriter.bytesWritten() == layerCount * sizeof(SkCanvasLayerState));
    canvasState->layerCount = layerCount;
    canvasState->layers = (SkCanvasLayerState*) sk_malloc_throw(layerWriter.bytesWritten());
    layerWriter.flatten(canvasState->layers);

    return canvasState.release();
}