C++ GrPaint类代码示例

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 ((nullptr == pixelRef) || 
        (pixelRef->info().width()  != bm.info().width()) ||
        (pixelRef->info().height() != bm.info().height())) {
        return nullptr;
    }

    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, nullptr, nullptr, nullptr)) {
            return nullptr;
        }

        // 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 nullptr;
        }

        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 nullptr;
        }
    }

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

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

    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.addColorFragmentProcessor(yuvToRgbProcessor);
    SkRect r = SkRect::MakeWH(SkIntToScalar(yuvInfo.fSize[0].fWidth),
                              SkIntToScalar(yuvInfo.fSize[0].fHeight));

//.........这里部分代码省略.........

sk_sp<SkImage> SkImage::MakeFromYUVTexturesCopy(GrContext* ctx , SkYUVColorSpace colorSpace,
                                                const GrBackendObject yuvTextureHandles[3],
                                                const SkISize yuvSizes[3],
                                                GrSurfaceOrigin origin) {
    const SkBudgeted budgeted = SkBudgeted::kYes;

    if (yuvSizes[0].fWidth <= 0 || yuvSizes[0].fHeight <= 0 ||
        yuvSizes[1].fWidth <= 0 || yuvSizes[1].fHeight <= 0 ||
        yuvSizes[2].fWidth <= 0 || yuvSizes[2].fHeight <= 0) {
        return nullptr;
    }
    static const GrPixelConfig kConfig = kAlpha_8_GrPixelConfig;
    GrBackendTextureDesc yDesc;
    yDesc.fConfig = kConfig;
    yDesc.fOrigin = origin;
    yDesc.fSampleCnt = 0;
    yDesc.fTextureHandle = yuvTextureHandles[0];
    yDesc.fWidth = yuvSizes[0].fWidth;
    yDesc.fHeight = yuvSizes[0].fHeight;

    GrBackendTextureDesc uDesc;
    uDesc.fConfig = kConfig;
    uDesc.fOrigin = origin;
    uDesc.fSampleCnt = 0;
    uDesc.fTextureHandle = yuvTextureHandles[1];
    uDesc.fWidth = yuvSizes[1].fWidth;
    uDesc.fHeight = yuvSizes[1].fHeight;

    GrBackendTextureDesc vDesc;
    vDesc.fConfig = kConfig;
    vDesc.fOrigin = origin;
    vDesc.fSampleCnt = 0;
    vDesc.fTextureHandle = yuvTextureHandles[2];
    vDesc.fWidth = yuvSizes[2].fWidth;
    vDesc.fHeight = yuvSizes[2].fHeight;

    SkAutoTUnref<GrTexture> yTex(ctx->textureProvider()->wrapBackendTexture(
        yDesc, kBorrow_GrWrapOwnership));
    SkAutoTUnref<GrTexture> uTex(ctx->textureProvider()->wrapBackendTexture(
        uDesc, kBorrow_GrWrapOwnership));
    SkAutoTUnref<GrTexture> vTex(ctx->textureProvider()->wrapBackendTexture(
        vDesc, kBorrow_GrWrapOwnership));
    if (!yTex || !uTex || !vTex) {
        return nullptr;
    }

    const int width = yuvSizes[0].fWidth;
    const int height = yuvSizes[0].fHeight;

    // Needs to be a render target in order to draw to it for the yuv->rgb conversion.
    sk_sp<GrDrawContext> drawContext(ctx->newDrawContext(SkBackingFit::kExact,
                                                         width, height,
                                                         kRGBA_8888_GrPixelConfig,
                                                         0,
                                                         origin));
    if (!drawContext) {
        return nullptr;
    }

    GrPaint paint;
    paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
    paint.addColorFragmentProcessor(GrYUVEffect::CreateYUVToRGB(yTex, uTex, vTex, yuvSizes,
                                                                colorSpace))->unref();

    const SkRect rect = SkRect::MakeWH(SkIntToScalar(width), SkIntToScalar(height));

    drawContext->drawRect(GrNoClip(), paint, SkMatrix::I(), rect);
    ctx->flushSurfaceWrites(drawContext->accessRenderTarget());
    return sk_make_sp<SkImage_Gpu>(width, height, kNeedNewImageUniqueID,
                                   kOpaque_SkAlphaType,
                                   drawContext->asTexture().get(), budgeted);
}

// creates a new texture that is the input texture scaled up. If optionalKey is valid it will be
// set on the new texture. stretch controls whether the scaling is done using nearest or bilerp
// filtering and the size to stretch the texture to.
GrTexture* stretch_texture(GrTexture* inputTexture, const Stretch& stretch,
                           SkPixelRef* pixelRef,
                           const GrUniqueKey& optionalKey) {
    SkASSERT(Stretch::kNone_Type != stretch.fType);

    GrContext* context = inputTexture->getContext();
    SkASSERT(context);
    const GrCaps* caps = context->caps();

    // Either it's a cache miss or the original wasn't cached to begin with.
    GrSurfaceDesc rtDesc = inputTexture->desc();
    rtDesc.fFlags =  rtDesc.fFlags | kRenderTarget_GrSurfaceFlag;
    rtDesc.fWidth  = stretch.fWidth;
    rtDesc.fHeight = stretch.fHeight;
    rtDesc.fConfig = GrMakePixelConfigUncompressed(rtDesc.fConfig);

    // If the config isn't renderable try converting to either A8 or an 32 bit config. Otherwise,
    // fail.
    if (!caps->isConfigRenderable(rtDesc.fConfig, false)) {
        if (GrPixelConfigIsAlphaOnly(rtDesc.fConfig)) {
            if (caps->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
                rtDesc.fConfig = kAlpha_8_GrPixelConfig;
            } else if (caps->isConfigRenderable(kSkia8888_GrPixelConfig, false)) {
                rtDesc.fConfig = kSkia8888_GrPixelConfig;
            } else {
                return nullptr;
            }
        } else if (kRGB_GrColorComponentFlags ==
                   (kRGB_GrColorComponentFlags & GrPixelConfigComponentMask(rtDesc.fConfig))) {
            if (caps->isConfigRenderable(kSkia8888_GrPixelConfig, false)) {
                rtDesc.fConfig = kSkia8888_GrPixelConfig;
            } else {
                return nullptr;
            }
        } else {
            return nullptr;
        }
    }

    GrTexture* stretched = create_texture_for_bmp(context, optionalKey, rtDesc, pixelRef, nullptr, 0);

    if (!stretched) {
        return nullptr;
    }
    GrPaint paint;

    // If filtering is not desired then we want to ensure all texels in the resampled image are
    // copies of texels from the original.
    GrTextureParams params(SkShader::kClamp_TileMode,
                           Stretch::kBilerp_Type == stretch.fType ?
                              GrTextureParams::kBilerp_FilterMode :
                              GrTextureParams::kNone_FilterMode);
    paint.addColorTextureProcessor(inputTexture, SkMatrix::I(), params);

    SkRect rect = SkRect::MakeWH(SkIntToScalar(rtDesc.fWidth), SkIntToScalar(rtDesc.fHeight));
    SkRect localRect = SkRect::MakeWH(1.f, 1.f);

    GrDrawContext* drawContext = context->drawContext();
    if (!drawContext) {
        return nullptr;
    }

    drawContext->drawNonAARectToRect(stretched->asRenderTarget(), GrClip::WideOpen(), paint,
                                     SkMatrix::I(), rect, localRect);

    return stretched;
}

GrTexture* GaussianBlur(GrContext* context,
                        GrTexture* srcTexture,
                        bool canClobberSrc,
                        const SkRect& rect,
                        bool cropToRect,
                        float sigmaX,
                        float sigmaY) {
    SkASSERT(NULL != context);

    GrContext::AutoRenderTarget art(context);

    GrContext::AutoMatrix am;
    am.setIdentity(context);

    SkIRect clearRect;
    int scaleFactorX, radiusX;
    int scaleFactorY, radiusY;
    sigmaX = adjust_sigma(sigmaX, &scaleFactorX, &radiusX);
    sigmaY = adjust_sigma(sigmaY, &scaleFactorY, &radiusY);

    SkRect srcRect(rect);
    scale_rect(&srcRect, 1.0f / scaleFactorX, 1.0f / scaleFactorY);
    srcRect.roundOut();
    scale_rect(&srcRect, static_cast<float>(scaleFactorX),
                         static_cast<float>(scaleFactorY));

    GrContext::AutoClip acs(context, SkRect::MakeWH(srcRect.width(), srcRect.height()));

    SkASSERT(kBGRA_8888_GrPixelConfig == srcTexture->config() ||
             kRGBA_8888_GrPixelConfig == srcTexture->config() ||
             kAlpha_8_GrPixelConfig == srcTexture->config());

    GrTextureDesc desc;
    desc.fFlags = kRenderTarget_GrTextureFlagBit | kNoStencil_GrTextureFlagBit;
    desc.fWidth = SkScalarFloorToInt(srcRect.width());
    desc.fHeight = SkScalarFloorToInt(srcRect.height());
    desc.fConfig = srcTexture->config();

    GrAutoScratchTexture temp1, temp2;
    GrTexture* dstTexture = temp1.set(context, desc);
    GrTexture* tempTexture = canClobberSrc ? srcTexture : temp2.set(context, desc);
    if (NULL == dstTexture || NULL == tempTexture) {
        return NULL;
    }

    for (int i = 1; i < scaleFactorX || i < scaleFactorY; i *= 2) {
        GrPaint paint;
        SkMatrix matrix;
        matrix.setIDiv(srcTexture->width(), srcTexture->height());
        context->setRenderTarget(dstTexture->asRenderTarget());
        SkRect dstRect(srcRect);
        if (cropToRect && i == 1) {
            dstRect.offset(-dstRect.fLeft, -dstRect.fTop);
            SkRect domain;
            matrix.mapRect(&domain, rect);
            domain.inset(i < scaleFactorX ? SK_ScalarHalf / srcTexture->width() : 0.0f,
                         i < scaleFactorY ? SK_ScalarHalf / srcTexture->height() : 0.0f);
            SkAutoTUnref<GrEffectRef> effect(GrTextureDomainEffect::Create(
                srcTexture,
                matrix,
                domain,
                GrTextureDomainEffect::kDecal_WrapMode,
                GrTextureParams::kBilerp_FilterMode));
            paint.addColorEffect(effect);
        } else {
            GrTextureParams params(SkShader::kClamp_TileMode, GrTextureParams::kBilerp_FilterMode);
            paint.addColorTextureEffect(srcTexture, matrix, params);
        }
        scale_rect(&dstRect, i < scaleFactorX ? 0.5f : 1.0f,
                             i < scaleFactorY ? 0.5f : 1.0f);
        context->drawRectToRect(paint, dstRect, srcRect);
        srcRect = dstRect;
        srcTexture = dstTexture;
        SkTSwap(dstTexture, tempTexture);
    }

    SkIRect srcIRect;
    srcRect.roundOut(&srcIRect);

    if (sigmaX > 0.0f) {
        if (scaleFactorX > 1) {
            // Clear out a radius to the right of the srcRect to prevent the
            // X convolution from reading garbage.
            clearRect = SkIRect::MakeXYWH(srcIRect.fRight, srcIRect.fTop,
                                          radiusX, srcIRect.height());
            context->clear(&clearRect, 0x0, false);
        }
        context->setRenderTarget(dstTexture->asRenderTarget());
        SkRect dstRect = SkRect::MakeWH(srcRect.width(), srcRect.height());
        convolve_gaussian(context, srcRect, dstRect, srcTexture,
                          Gr1DKernelEffect::kX_Direction, radiusX, sigmaX, cropToRect);
        srcTexture = dstTexture;
        srcRect = dstRect;
        SkTSwap(dstTexture, tempTexture);
    }

    if (sigmaY > 0.0f) {
        if (scaleFactorY > 1 || sigmaX > 0.0f) {
            // Clear out a radius below the srcRect to prevent the Y
            // convolution from reading garbage.
//.........这里部分代码省略.........

bool GrDrawingManager::ProgramUnitTest(GrContext* context, int maxStages, int maxLevels) {
    GrDrawingManager* drawingManager = context->contextPriv().drawingManager();

    sk_sp<GrTextureProxy> proxies[2];

    // setup dummy textures
    GrSurfaceDesc dummyDesc;
    dummyDesc.fFlags = kRenderTarget_GrSurfaceFlag;
    dummyDesc.fOrigin = kBottomLeft_GrSurfaceOrigin;
    dummyDesc.fConfig = kRGBA_8888_GrPixelConfig;
    dummyDesc.fWidth = 34;
    dummyDesc.fHeight = 18;
    proxies[0] = GrSurfaceProxy::MakeDeferred(context->resourceProvider(),
                                              dummyDesc, SkBudgeted::kNo, nullptr, 0);
    dummyDesc.fFlags = kNone_GrSurfaceFlags;
    dummyDesc.fOrigin = kTopLeft_GrSurfaceOrigin;
    dummyDesc.fConfig = kAlpha_8_GrPixelConfig;
    dummyDesc.fWidth = 16;
    dummyDesc.fHeight = 22;
    proxies[1] = GrSurfaceProxy::MakeDeferred(context->resourceProvider(),
                                              dummyDesc, SkBudgeted::kNo, nullptr, 0);

    if (!proxies[0] || !proxies[1]) {
        SkDebugf("Could not allocate dummy textures");
        return false;
    }

    // dummy scissor state
    GrScissorState scissor;

    SkRandom random;
    static const int NUM_TESTS = 1024;
    for (int t = 0; t < NUM_TESTS; t++) {
        // setup random render target(can fail)
        sk_sp<GrRenderTargetContext> renderTargetContext(random_render_target_context(
            context, &random, context->caps()));
        if (!renderTargetContext) {
            SkDebugf("Could not allocate renderTargetContext");
            return false;
        }

        GrPaint paint;
        GrProcessorTestData ptd(&random, context, renderTargetContext.get(), proxies);
        set_random_color_coverage_stages(&paint, &ptd, maxStages, maxLevels);
        set_random_xpf(&paint, &ptd);
        set_random_state(&paint, &random);
        GrDrawRandomOp(&random, renderTargetContext.get(), std::move(paint));
    }
    // Flush everything, test passes if flush is successful(ie, no asserts are hit, no crashes)
    drawingManager->flush(nullptr);

    // Validate that GrFPs work correctly without an input.
    sk_sp<GrRenderTargetContext> renderTargetContext(context->makeDeferredRenderTargetContext(
                                                                           SkBackingFit::kExact,
                                                                           kRenderTargetWidth,
                                                                           kRenderTargetHeight,
                                                                           kRGBA_8888_GrPixelConfig,
                                                                           nullptr));
    if (!renderTargetContext) {
        SkDebugf("Could not allocate a renderTargetContext");
        return false;
    }

    int fpFactoryCnt = GrProcessorTestFactory<GrFragmentProcessor>::Count();
    for (int i = 0; i < fpFactoryCnt; ++i) {
        // Since FP factories internally randomize, call each 10 times.
        for (int j = 0; j < 10; ++j) {
            GrProcessorTestData ptd(&random, context, renderTargetContext.get(), proxies);

            GrPaint paint;
            paint.setXPFactory(GrPorterDuffXPFactory::Get(SkBlendMode::kSrc));
            sk_sp<GrFragmentProcessor> fp(
                GrProcessorTestFactory<GrFragmentProcessor>::MakeIdx(i, &ptd));
            sk_sp<GrFragmentProcessor> blockFP(
                BlockInputFragmentProcessor::Make(std::move(fp)));
            paint.addColorFragmentProcessor(std::move(blockFP));
            GrDrawRandomOp(&random, renderTargetContext.get(), std::move(paint));
            drawingManager->flush(nullptr);
        }
    }

    return true;
}

GrTexture* GaussianBlur(GrContext* context,
                        GrTexture* srcTexture,
                        bool canClobberSrc,
                        const SkRect& rect,
                        bool cropToRect,
                        float sigmaX,
                        float sigmaY) {
    SkASSERT(context);

    SkIRect clearRect;
    int scaleFactorX, radiusX;
    int scaleFactorY, radiusY;
    int maxTextureSize = context->getMaxTextureSize();
    sigmaX = adjust_sigma(sigmaX, maxTextureSize, &scaleFactorX, &radiusX);
    sigmaY = adjust_sigma(sigmaY, maxTextureSize, &scaleFactorY, &radiusY);

    SkRect srcRect(rect);
    scale_rect(&srcRect, 1.0f / scaleFactorX, 1.0f / scaleFactorY);
    srcRect.roundOut(&srcRect);
    scale_rect(&srcRect, static_cast<float>(scaleFactorX),
                         static_cast<float>(scaleFactorY));

    // setup new clip
    GrClip clip(SkRect::MakeWH(srcRect.width(), srcRect.height()));

    SkASSERT(kBGRA_8888_GrPixelConfig == srcTexture->config() ||
             kRGBA_8888_GrPixelConfig == srcTexture->config() ||
             kAlpha_8_GrPixelConfig == srcTexture->config());

    GrSurfaceDesc desc;
    desc.fFlags = kRenderTarget_GrSurfaceFlag;
    desc.fWidth = SkScalarFloorToInt(srcRect.width());
    desc.fHeight = SkScalarFloorToInt(srcRect.height());
    desc.fConfig = srcTexture->config();

    GrTexture* dstTexture;
    GrTexture* tempTexture;
    SkAutoTUnref<GrTexture> temp1, temp2;

    temp1.reset(context->textureProvider()->refScratchTexture(
        desc, GrTextureProvider::kApprox_ScratchTexMatch));
    dstTexture = temp1.get();
    if (canClobberSrc) {
        tempTexture = srcTexture;
    } else {
        temp2.reset(context->textureProvider()->refScratchTexture(
            desc, GrTextureProvider::kApprox_ScratchTexMatch));
        tempTexture = temp2.get();
    }

    if (NULL == dstTexture || NULL == tempTexture) {
        return NULL;
    }

    GrDrawContext* drawContext = context->drawContext();
    if (!drawContext) {
        return NULL;
    }

    for (int i = 1; i < scaleFactorX || i < scaleFactorY; i *= 2) {
        GrPaint paint;
        SkMatrix matrix;
        matrix.setIDiv(srcTexture->width(), srcTexture->height());
        SkRect dstRect(srcRect);
        if (cropToRect && i == 1) {
            dstRect.offset(-dstRect.fLeft, -dstRect.fTop);
            SkRect domain;
            matrix.mapRect(&domain, rect);
            domain.inset(i < scaleFactorX ? SK_ScalarHalf / srcTexture->width() : 0.0f,
                         i < scaleFactorY ? SK_ScalarHalf / srcTexture->height() : 0.0f);
            SkAutoTUnref<GrFragmentProcessor> fp(   GrTextureDomainEffect::Create(
                srcTexture,
                matrix,
                domain,
                GrTextureDomain::kDecal_Mode,
                GrTextureParams::kBilerp_FilterMode));
            paint.addColorProcessor(fp);
        } else {
            GrTextureParams params(SkShader::kClamp_TileMode, GrTextureParams::kBilerp_FilterMode);
            paint.addColorTextureProcessor(srcTexture, matrix, params);
        }
        scale_rect(&dstRect, i < scaleFactorX ? 0.5f : 1.0f,
                             i < scaleFactorY ? 0.5f : 1.0f);
        drawContext->drawNonAARectToRect(dstTexture->asRenderTarget(), clip, paint, SkMatrix::I(),
                                         dstRect, srcRect);
        srcRect = dstRect;
        srcTexture = dstTexture;
        SkTSwap(dstTexture, tempTexture);
    }

    const SkIRect srcIRect = srcRect.roundOut();

    // For really small blurs(Certainly no wider than 5x5 on desktop gpus) it is faster to just
    // launch a single non separable kernel vs two launches
    if (sigmaX > 0.0f && sigmaY > 0 &&
            (2 * radiusX + 1) * (2 * radiusY + 1) <= MAX_KERNEL_SIZE) {
        // We shouldn't be scaling because this is a small size blur
        SkASSERT((scaleFactorX == scaleFactorY) == 1);
        SkRect dstRect = SkRect::MakeWH(srcRect.width(), srcRect.height());
        convolve_gaussian_2d(drawContext, dstTexture->asRenderTarget(), clip, srcRect, dstRect,
//.........这里部分代码省略.........

bool GrDefaultPathRenderer::internalDrawPath(GrDrawContext* drawContext,
                                             const GrPaint& paint,
                                             const GrUserStencilSettings& userStencilSettings,
                                             const GrClip& clip,
                                             const SkMatrix& viewMatrix,
                                             const GrShape& shape,
                                             bool stencilOnly) {
    SkPath path;
    shape.asPath(&path);

    SkScalar hairlineCoverage;
    uint8_t newCoverage = 0xff;
    bool isHairline = false;
    if (IsStrokeHairlineOrEquivalent(shape.style(), viewMatrix, &hairlineCoverage)) {
        newCoverage = SkScalarRoundToInt(hairlineCoverage * 0xff);
        isHairline = true;
    } else {
        SkASSERT(shape.style().isSimpleFill());
    }

    int                          passCount = 0;
    const GrUserStencilSettings* passes[3];
    GrDrawFace                   drawFace[3];
    bool                         reverse = false;
    bool                         lastPassIsBounds;

    if (isHairline) {
        passCount = 1;
        if (stencilOnly) {
            passes[0] = &gDirectToStencil;
        } else {
            passes[0] = &userStencilSettings;
        }
        lastPassIsBounds = false;
        drawFace[0] = GrDrawFace::kBoth;
    } else {
        if (single_pass_shape(shape)) {
            passCount = 1;
            if (stencilOnly) {
                passes[0] = &gDirectToStencil;
            } else {
                passes[0] = &userStencilSettings;
            }
            drawFace[0] = GrDrawFace::kBoth;
            lastPassIsBounds = false;
        } else {
            switch (path.getFillType()) {
                case SkPath::kInverseEvenOdd_FillType:
                    reverse = true;
                    // fallthrough
                case SkPath::kEvenOdd_FillType:
                    passes[0] = &gEOStencilPass;
                    if (stencilOnly) {
                        passCount = 1;
                        lastPassIsBounds = false;
                    } else {
                        passCount = 2;
                        lastPassIsBounds = true;
                        if (reverse) {
                            passes[1] = &gInvEOColorPass;
                        } else {
                            passes[1] = &gEOColorPass;
                        }
                    }
                    drawFace[0] = drawFace[1] = GrDrawFace::kBoth;
                    break;

                case SkPath::kInverseWinding_FillType:
                    reverse = true;
                    // fallthrough
                case SkPath::kWinding_FillType:
                    if (fSeparateStencil) {
                        if (fStencilWrapOps) {
                            passes[0] = &gWindStencilSeparateWithWrap;
                        } else {
                            passes[0] = &gWindStencilSeparateNoWrap;
                        }
                        passCount = 2;
                        drawFace[0] = GrDrawFace::kBoth;
                    } else {
                        if (fStencilWrapOps) {
                            passes[0] = &gWindSingleStencilWithWrapInc;
                            passes[1] = &gWindSingleStencilWithWrapDec;
                        } else {
                            passes[0] = &gWindSingleStencilNoWrapInc;
                            passes[1] = &gWindSingleStencilNoWrapDec;
                        }
                        // which is cw and which is ccw is arbitrary.
                        drawFace[0] = GrDrawFace::kCW;
                        drawFace[1] = GrDrawFace::kCCW;
                        passCount = 3;
                    }
                    if (stencilOnly) {
                        lastPassIsBounds = false;
                        --passCount;
                    } else {
                        lastPassIsBounds = true;
                        drawFace[passCount-1] = GrDrawFace::kBoth;
                        if (reverse) {
                            passes[passCount-1] = &gInvWindColorPass;
//.........这里部分代码省略.........

sk_sp<SkSpecialImage> SkXfermodeImageFilter::filterImageGPU(SkSpecialImage* source,
                                                            sk_sp<SkSpecialImage> background,
                                                            const SkIPoint& backgroundOffset,
                                                            sk_sp<SkSpecialImage> foreground,
                                                            const SkIPoint& foregroundOffset,
                                                            const SkIRect& bounds) const {
    SkASSERT(source->isTextureBacked());

    GrContext* context = source->getContext();

    sk_sp<GrTexture> backgroundTex, foregroundTex;
    
    if (background) {
        backgroundTex = background->asTextureRef(context);
    }

    if (foreground) {
        foregroundTex = foreground->asTextureRef(context);
    }

    GrPaint paint;
    // SRGBTODO: AllowSRGBInputs?
    sk_sp<GrFragmentProcessor> bgFP;

    if (backgroundTex) {
        SkMatrix backgroundMatrix;
        backgroundMatrix.setIDiv(backgroundTex->width(), backgroundTex->height());
        backgroundMatrix.preTranslate(SkIntToScalar(-backgroundOffset.fX),
                                      SkIntToScalar(-backgroundOffset.fY));
        bgFP = GrTextureDomainEffect::Make(
                            backgroundTex.get(), backgroundMatrix,
                            GrTextureDomain::MakeTexelDomain(backgroundTex.get(),
                                                             background->subset()),
                            GrTextureDomain::kDecal_Mode,
                            GrTextureParams::kNone_FilterMode);
    } else {
        bgFP = GrConstColorProcessor::Make(GrColor_TRANSPARENT_BLACK,
                                             GrConstColorProcessor::kIgnore_InputMode);
    }

    if (foregroundTex) {
        SkMatrix foregroundMatrix;
        foregroundMatrix.setIDiv(foregroundTex->width(), foregroundTex->height());
        foregroundMatrix.preTranslate(SkIntToScalar(-foregroundOffset.fX),
                                      SkIntToScalar(-foregroundOffset.fY));

        sk_sp<GrFragmentProcessor> foregroundFP;

        foregroundFP = GrTextureDomainEffect::Make(
                            foregroundTex.get(), foregroundMatrix,
                            GrTextureDomain::MakeTexelDomain(foregroundTex.get(), 
                                                             foreground->subset()),
                            GrTextureDomain::kDecal_Mode,
                            GrTextureParams::kNone_FilterMode);

        paint.addColorFragmentProcessor(std::move(foregroundFP));

        // A null fMode is interpreted to mean kSrcOver_Mode (to match raster).
        SkAutoTUnref<SkXfermode> mode(SkSafeRef(fMode.get()));
        if (!mode) {
            // It would be awesome to use SkXfermode::Create here but it knows better
            // than us and won't return a kSrcOver_Mode SkXfermode. That means we
            // have to get one the hard way.
            struct ProcCoeff rec;
            rec.fProc = SkXfermode::GetProc(SkXfermode::kSrcOver_Mode);
            SkXfermode::ModeAsCoeff(SkXfermode::kSrcOver_Mode, &rec.fSC, &rec.fDC);

            mode.reset(new SkProcCoeffXfermode(rec, SkXfermode::kSrcOver_Mode));
        }

        sk_sp<GrFragmentProcessor> xferFP(
            mode->makeFragmentProcessorForImageFilter(std::move(bgFP)));

        // A null 'xferFP' here means kSrc_Mode was used in which case we can just proceed
        if (xferFP) {
            paint.addColorFragmentProcessor(std::move(xferFP));
        }
    } else {
        paint.addColorFragmentProcessor(std::move(bgFP));
    }

    paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);

    sk_sp<GrDrawContext> drawContext(context->newDrawContext(SkBackingFit::kApprox,
                                                             bounds.width(), bounds.height(),
                                                             kSkia8888_GrPixelConfig));
    if (!drawContext) {
        return nullptr;
    }

    SkMatrix matrix;
    matrix.setTranslate(SkIntToScalar(-bounds.left()), SkIntToScalar(-bounds.top()));
    drawContext->drawRect(GrNoClip(), paint, matrix, SkRect::Make(bounds));

    return SkSpecialImage::MakeFromGpu(SkIRect::MakeWH(bounds.width(), bounds.height()),
                                       kNeedNewImageUniqueID_SpecialImage,
                                       drawContext->asTexture());
}

static sk_sp<SkImage> make_from_yuv_textures_copy(GrContext* ctx, SkYUVColorSpace colorSpace,
                                                  bool nv12,
                                                  const GrBackendObject yuvTextureHandles[],
                                                  const SkISize yuvSizes[],
                                                  GrSurfaceOrigin origin,
                                                  sk_sp<SkColorSpace> imageColorSpace) {
    const SkBudgeted budgeted = SkBudgeted::kYes;

    if (yuvSizes[0].fWidth <= 0 || yuvSizes[0].fHeight <= 0 || yuvSizes[1].fWidth <= 0 ||
        yuvSizes[1].fHeight <= 0) {
        return nullptr;
    }
    if (!nv12 && (yuvSizes[2].fWidth <= 0 || yuvSizes[2].fHeight <= 0)) {
        return nullptr;
    }

    const GrPixelConfig kConfig = nv12 ? kRGBA_8888_GrPixelConfig : kAlpha_8_GrPixelConfig;

    GrBackendTextureDesc yDesc;
    yDesc.fConfig = kConfig;
    yDesc.fOrigin = origin;
    yDesc.fSampleCnt = 0;
    yDesc.fTextureHandle = yuvTextureHandles[0];
    yDesc.fWidth = yuvSizes[0].fWidth;
    yDesc.fHeight = yuvSizes[0].fHeight;

    GrBackendTextureDesc uDesc;
    uDesc.fConfig = kConfig;
    uDesc.fOrigin = origin;
    uDesc.fSampleCnt = 0;
    uDesc.fTextureHandle = yuvTextureHandles[1];
    uDesc.fWidth = yuvSizes[1].fWidth;
    uDesc.fHeight = yuvSizes[1].fHeight;

    sk_sp<GrSurfaceProxy> yProxy = GrSurfaceProxy::MakeWrappedBackend(ctx, yDesc);
    sk_sp<GrSurfaceProxy> uProxy = GrSurfaceProxy::MakeWrappedBackend(ctx, uDesc);
    sk_sp<GrSurfaceProxy> vProxy;

    if (nv12) {
        vProxy = uProxy;
    } else {
        GrBackendTextureDesc vDesc;
        vDesc.fConfig = kConfig;
        vDesc.fOrigin = origin;
        vDesc.fSampleCnt = 0;
        vDesc.fTextureHandle = yuvTextureHandles[2];
        vDesc.fWidth = yuvSizes[2].fWidth;
        vDesc.fHeight = yuvSizes[2].fHeight;

        vProxy = GrSurfaceProxy::MakeWrappedBackend(ctx, vDesc);
    }
    if (!yProxy || !uProxy || !vProxy) {
        return nullptr;
    }

    const int width = yuvSizes[0].fWidth;
    const int height = yuvSizes[0].fHeight;

    // Needs to be a render target in order to draw to it for the yuv->rgb conversion.
    sk_sp<GrRenderTargetContext> renderTargetContext(ctx->makeRenderTargetContext(
                                                                         SkBackingFit::kExact,
                                                                         width, height,
                                                                         kRGBA_8888_GrPixelConfig,
                                                                         std::move(imageColorSpace),
                                                                         0,
                                                                         origin));
    if (!renderTargetContext) {
        return nullptr;
    }

    GrPaint paint;
    paint.setPorterDuffXPFactory(SkBlendMode::kSrc);
    paint.addColorFragmentProcessor(
        GrYUVEffect::MakeYUVToRGB(ctx->resourceProvider(),
                                  sk_ref_sp(yProxy->asTextureProxy()),
                                  sk_ref_sp(uProxy->asTextureProxy()),
                                  sk_ref_sp(vProxy->asTextureProxy()), yuvSizes, colorSpace, nv12));

    const SkRect rect = SkRect::MakeIWH(width, height);

    renderTargetContext->drawRect(GrNoClip(), std::move(paint), GrAA::kNo, SkMatrix::I(), rect);

    if (!renderTargetContext->asSurfaceProxy()) {
        return nullptr;
    }
    ctx->contextPriv().flushSurfaceWrites(renderTargetContext->asSurfaceProxy());

    // MDB: this call is okay bc we know 'renderTargetContext' was exact
    return sk_make_sp<SkImage_Gpu>(ctx, kNeedNewImageUniqueID,
                                   kOpaque_SkAlphaType, renderTargetContext->asTextureProxyRef(),
                                   renderTargetContext->refColorSpace(), budgeted);
}

bool SkDisplacementMapEffect::filterImageGPU(Proxy* proxy, const SkBitmap& src, const Context& ctx,
                                             SkBitmap* result, SkIPoint* offset) const {
    SkBitmap colorBM = src;
    SkIPoint colorOffset = SkIPoint::Make(0, 0);
    if (!this->filterInputGPU(1, proxy, src, ctx, &colorBM, &colorOffset)) {
        return false;
    }
    SkBitmap displacementBM = src;
    SkIPoint displacementOffset = SkIPoint::Make(0, 0);
    if (!this->filterInputGPU(0, proxy, src, ctx, &displacementBM, &displacementOffset)) {
        return false;
    }
    SkIRect bounds;
    // Since GrDisplacementMapEffect does bounds checking on color pixel access, we don't need to
    // pad the color bitmap to bounds here.
    if (!this->applyCropRect(ctx, colorBM, colorOffset, &bounds)) {
        return false;
    }
    SkIRect displBounds;
    if (!this->applyCropRect(ctx, proxy, displacementBM,
                             &displacementOffset, &displBounds, &displacementBM)) {
        return false;
    }
    if (!bounds.intersect(displBounds)) {
        return false;
    }
    GrTexture* color = colorBM.getTexture();
    GrTexture* displacement = displacementBM.getTexture();
    GrContext* context = color->getContext();

    GrSurfaceDesc desc;
    desc.fFlags = kRenderTarget_GrSurfaceFlag;
    desc.fWidth = bounds.width();
    desc.fHeight = bounds.height();
    desc.fConfig = kSkia8888_GrPixelConfig;

    SkAutoTUnref<GrTexture> dst(context->textureProvider()->createApproxTexture(desc));

    if (!dst) {
        return false;
    }

    SkVector scale = SkVector::Make(fScale, fScale);
    ctx.ctm().mapVectors(&scale, 1);

    GrPaint paint;
    SkMatrix offsetMatrix = GrCoordTransform::MakeDivByTextureWHMatrix(displacement);
    offsetMatrix.preTranslate(SkIntToScalar(colorOffset.fX - displacementOffset.fX),
                              SkIntToScalar(colorOffset.fY - displacementOffset.fY));

    paint.addColorFragmentProcessor(
        GrDisplacementMapEffect::Create(fXChannelSelector,
                                        fYChannelSelector,
                                        scale,
                                        displacement,
                                        offsetMatrix,
                                        color,
                                        colorBM.dimensions()))->unref();
    paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
    SkIRect colorBounds = bounds;
    colorBounds.offset(-colorOffset);
    SkMatrix matrix;
    matrix.setTranslate(-SkIntToScalar(colorBounds.x()),
                        -SkIntToScalar(colorBounds.y()));

    SkAutoTUnref<GrDrawContext> drawContext(context->drawContext(dst->asRenderTarget()));
    if (!drawContext) {
        return false;
    }

    drawContext->drawRect(GrClip::WideOpen(), paint, matrix, SkRect::Make(colorBounds));
    offset->fX = bounds.left();
    offset->fY = bounds.top();
    GrWrapTextureInBitmap(dst, bounds.width(), bounds.height(), false, result);
    return true;
}

GrTexture* GaussianBlur(GrContext* context,
                        GrTexture* srcTexture,
                        bool canClobberSrc,
                        const SkRect& dstBounds,
                        const SkRect* srcBounds,
                        float sigmaX,
                        float sigmaY,
                        GrTextureProvider::SizeConstraint constraint) {
    SkASSERT(context);
    SkIRect clearRect;
    int scaleFactorX, radiusX;
    int scaleFactorY, radiusY;
    int maxTextureSize = context->caps()->maxTextureSize();
    sigmaX = adjust_sigma(sigmaX, maxTextureSize, &scaleFactorX, &radiusX);
    sigmaY = adjust_sigma(sigmaY, maxTextureSize, &scaleFactorY, &radiusY);

    SkPoint srcOffset = SkPoint::Make(-dstBounds.x(), -dstBounds.y());
    SkRect localDstBounds = SkRect::MakeWH(dstBounds.width(), dstBounds.height());
    SkRect localSrcBounds;
    SkRect srcRect;
    if (srcBounds) {
        srcRect = localSrcBounds = *srcBounds;
        srcRect.offset(srcOffset);
        srcBounds = &localSrcBounds;
    } else {
        srcRect = localDstBounds;
    }

    scale_rect(&srcRect, 1.0f / scaleFactorX, 1.0f / scaleFactorY);
    srcRect.roundOut(&srcRect);
    scale_rect(&srcRect, static_cast<float>(scaleFactorX),
               static_cast<float>(scaleFactorY));

    // setup new clip
    GrClip clip(localDstBounds);

    SkASSERT(kBGRA_8888_GrPixelConfig == srcTexture->config() ||
             kRGBA_8888_GrPixelConfig == srcTexture->config() ||
             kAlpha_8_GrPixelConfig == srcTexture->config());

    GrSurfaceDesc desc;
    desc.fFlags = kRenderTarget_GrSurfaceFlag;
    desc.fWidth = SkScalarFloorToInt(dstBounds.width());
    desc.fHeight = SkScalarFloorToInt(dstBounds.height());
    desc.fConfig = srcTexture->config();

    GrTexture* dstTexture;
    GrTexture* tempTexture;
    SkAutoTUnref<GrTexture> temp1, temp2;

    temp1.reset(context->textureProvider()->createTexture(desc, constraint));
    dstTexture = temp1.get();
    if (canClobberSrc) {
        tempTexture = srcTexture;
    } else {
        temp2.reset(context->textureProvider()->createTexture(desc, constraint));
        tempTexture = temp2.get();
    }

    if (nullptr == dstTexture || nullptr == tempTexture) {
        return nullptr;
    }

    SkAutoTUnref<GrDrawContext> srcDrawContext;

    for (int i = 1; i < scaleFactorX || i < scaleFactorY; i *= 2) {
        GrPaint paint;
        SkMatrix matrix;
        matrix.setIDiv(srcTexture->width(), srcTexture->height());
        SkRect dstRect(srcRect);
        if (srcBounds && i == 1) {
            SkRect domain;
            matrix.mapRect(&domain, *srcBounds);
            domain.inset((i < scaleFactorX) ? SK_ScalarHalf / srcTexture->width() : 0.0f,
                         (i < scaleFactorY) ? SK_ScalarHalf / srcTexture->height() : 0.0f);
            SkAutoTUnref<const GrFragmentProcessor> fp(GrTextureDomainEffect::Create(
                        srcTexture,
                        matrix,
                        domain,
                        GrTextureDomain::kDecal_Mode,
                        GrTextureParams::kBilerp_FilterMode));
            paint.addColorFragmentProcessor(fp);
            srcRect.offset(-srcOffset);
            srcOffset.set(0, 0);
        } else {
            GrTextureParams params(SkShader::kClamp_TileMode, GrTextureParams::kBilerp_FilterMode);
            paint.addColorTextureProcessor(srcTexture, matrix, params);
        }
        paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
        scale_rect(&dstRect, i < scaleFactorX ? 0.5f : 1.0f,
                   i < scaleFactorY ? 0.5f : 1.0f);

        SkAutoTUnref<GrDrawContext> dstDrawContext(
            context->drawContext(dstTexture->asRenderTarget()));
        if (!dstDrawContext) {
            return nullptr;
        }
        dstDrawContext->fillRectToRect(clip, paint, SkMatrix::I(), dstRect, srcRect);

        srcDrawContext.swap(dstDrawContext);
//.........这里部分代码省略.........

bool GrDashingEffect::DrawDashLine(const SkPoint pts[2], const GrPaint& paint,
                                   const GrStrokeInfo& strokeInfo, GrGpu* gpu,
                                   GrDrawTarget* target, const SkMatrix& vm) {

    if (!can_fast_path_dash(pts, strokeInfo, *target, vm)) {
        return false;
    }

    const SkPathEffect::DashInfo& info = strokeInfo.getDashInfo();

    SkPaint::Cap cap = strokeInfo.getStrokeRec().getCap();

    SkScalar srcStrokeWidth = strokeInfo.getStrokeRec().getWidth();

    // the phase should be normalized to be [0, sum of all intervals)
    SkASSERT(info.fPhase >= 0 && info.fPhase < info.fIntervals[0] + info.fIntervals[1]);

    SkScalar srcPhase = info.fPhase;

    // Rotate the src pts so they are aligned horizontally with pts[0].fX < pts[1].fX
    SkMatrix srcRotInv;
    SkPoint ptsRot[2];
    if (pts[0].fY != pts[1].fY || pts[0].fX > pts[1].fX) {
        SkMatrix rotMatrix;
        align_to_x_axis(pts, &rotMatrix, ptsRot);
        if(!rotMatrix.invert(&srcRotInv)) {
            GrPrintf("Failed to create invertible rotation matrix!\n");
            return false;
        }
    } else {
        srcRotInv.reset();
        memcpy(ptsRot, pts, 2 * sizeof(SkPoint));
    }

    bool useAA = paint.isAntiAlias();

    // Scale corrections of intervals and stroke from view matrix
    SkScalar parallelScale;
    SkScalar perpScale;
    calc_dash_scaling(&parallelScale, &perpScale, vm, ptsRot);

    bool hasCap = SkPaint::kSquare_Cap == cap && 0 != srcStrokeWidth;

    // We always want to at least stroke out half a pixel on each side in device space
    // so 0.5f / perpScale gives us this min in src space
    SkScalar halfSrcStroke = SkMaxScalar(srcStrokeWidth * 0.5f, 0.5f / perpScale);

    SkScalar strokeAdj;
    if (!hasCap) {
        strokeAdj = 0.f;
    } else {
        strokeAdj = halfSrcStroke;
    }

    SkScalar startAdj = 0;

    SkMatrix combinedMatrix = srcRotInv;
    combinedMatrix.postConcat(vm);

    bool lineDone = false;
    SkRect startRect;
    bool hasStartRect = false;
    // If we are using AA, check to see if we are drawing a partial dash at the start. If so
    // draw it separately here and adjust our start point accordingly
    if (useAA) {
        if (srcPhase > 0 && srcPhase < info.fIntervals[0]) {
            SkPoint startPts[2];
            startPts[0] = ptsRot[0];
            startPts[1].fY = startPts[0].fY;
            startPts[1].fX = SkMinScalar(startPts[0].fX + info.fIntervals[0] - srcPhase,
                                         ptsRot[1].fX);
            startRect.set(startPts, 2);
            startRect.outset(strokeAdj, halfSrcStroke);

            hasStartRect = true;
            startAdj = info.fIntervals[0] + info.fIntervals[1] - srcPhase;
        }
    }

    // adjustments for start and end of bounding rect so we only draw dash intervals
    // contained in the original line segment.
    startAdj += calc_start_adjustment(info);
    if (startAdj != 0) {
        ptsRot[0].fX += startAdj;
        srcPhase = 0;
    }
    SkScalar endingInterval = 0;
    SkScalar endAdj = calc_end_adjustment(info, ptsRot, srcPhase, &endingInterval);
    ptsRot[1].fX -= endAdj;
    if (ptsRot[0].fX >= ptsRot[1].fX) {
        lineDone = true;
    }

    SkRect endRect;
    bool hasEndRect = false;
    // If we are using AA, check to see if we are drawing a partial dash at then end. If so
    // draw it separately here and adjust our end point accordingly
    if (useAA && !lineDone) {
        // If we adjusted the end then we will not be drawing a partial dash at the end.
        // If we didn't adjust the end point then we just need to make sure the ending
//.........这里部分代码省略.........