C++ SkMatrix::postScale方法代码示例

static SkBitmap make_bmp(int w, int h) {
    SkBitmap bmp;
    bmp.allocN32Pixels(w, h, true);

    SkCanvas canvas(bmp);
    SkScalar wScalar = SkIntToScalar(w);
    SkScalar hScalar = SkIntToScalar(h);

    SkPoint     pt = { wScalar / 2, hScalar / 2 };

    SkScalar    radius = 3 * SkMaxScalar(wScalar, hScalar);

    SkColor     colors[] = { SK_ColorDKGRAY, 0xFF222255,
                             0xFF331133, 0xFF884422,
                             0xFF000022, SK_ColorWHITE,
                             0xFFAABBCC};

    SkScalar    pos[] = {0,
                         SK_Scalar1 / 6,
                         2 * SK_Scalar1 / 6,
                         3 * SK_Scalar1 / 6,
                         4 * SK_Scalar1 / 6,
                         5 * SK_Scalar1 / 6,
                         SK_Scalar1};

    SkPaint paint;
    SkRect rect = SkRect::MakeWH(wScalar, hScalar);
    SkMatrix mat = SkMatrix::I();
    for (int i = 0; i < 4; ++i) {
        paint.setShader(SkGradientShader::CreateRadial(
                        pt, radius,
                        colors, pos,
                        SK_ARRAY_COUNT(colors),
                        SkShader::kRepeat_TileMode,
                        0, &mat))->unref();
        canvas.drawRect(rect, paint);
        rect.inset(wScalar / 8, hScalar / 8);
        mat.preTranslate(6 * wScalar, 6 * hScalar);
        mat.postScale(SK_Scalar1 / 3, SK_Scalar1 / 3);
    }

    paint.setAntiAlias(true);
    sk_tool_utils::set_portable_typeface(&paint);
    paint.setTextSize(wScalar / 2.2f);
    paint.setShader(0);
    paint.setColor(SK_ColorLTGRAY);
    static const char kTxt[] = "Skia";
    SkPoint texPos = { wScalar / 17, hScalar / 2 + paint.getTextSize() / 2.5f };
    canvas.drawText(kTxt, SK_ARRAY_COUNT(kTxt)-1, texPos.fX, texPos.fY, paint);
    paint.setColor(SK_ColorBLACK);
    paint.setStyle(SkPaint::kStroke_Style);
    paint.setStrokeWidth(SK_Scalar1);
    canvas.drawText(kTxt, SK_ARRAY_COUNT(kTxt)-1, texPos.fX, texPos.fY, paint);
    return bmp;
}

// Creates a bitmap and a matching image.
static sk_sp<SkImage> makebm(SkCanvas* origCanvas, SkBitmap* resultBM, int w, int h) {
    SkImageInfo info = SkImageInfo::MakeN32Premul(w, h);

    auto surface(sk_tool_utils::makeSurface(origCanvas, info));
    SkCanvas* canvas = surface->getCanvas();

    canvas->clear(SK_ColorTRANSPARENT);

    SkScalar wScalar = SkIntToScalar(w);
    SkScalar hScalar = SkIntToScalar(h);

    SkPoint     pt = { wScalar / 2, hScalar / 2 };

    SkScalar    radius = 4 * SkMaxScalar(wScalar, hScalar);

    SkColor     colors[] = { SK_ColorRED, SK_ColorYELLOW,
                             SK_ColorGREEN, SK_ColorMAGENTA,
                             SK_ColorBLUE, SK_ColorCYAN,
                             SK_ColorRED};

    SkScalar    pos[] = {0,
                         SK_Scalar1 / 6,
                         2 * SK_Scalar1 / 6,
                         3 * SK_Scalar1 / 6,
                         4 * SK_Scalar1 / 6,
                         5 * SK_Scalar1 / 6,
                         SK_Scalar1};

    SkPaint     paint;
    SkRect rect = SkRect::MakeWH(wScalar, hScalar);
    SkMatrix mat = SkMatrix::I();
    for (int i = 0; i < 4; ++i) {
        paint.setShader(SkGradientShader::MakeRadial(
                        pt, radius,
                        colors, pos,
                        SK_ARRAY_COUNT(colors),
                        SkShader::kRepeat_TileMode,
                        0, &mat));
        canvas->drawRect(rect, paint);
        rect.inset(wScalar / 8, hScalar / 8);
        mat.postScale(SK_Scalar1 / 4, SK_Scalar1 / 4);
    }

    auto image = surface->makeImageSnapshot();

    SkBitmap tempBM;

    image->asLegacyBitmap(&tempBM);

    // Let backends know we won't change this, so they don't have to deep copy it defensively.
    tempBM.setImmutable();
    *resultBM = tempBM;

    return image;
}

static SkMatrix pts_to_unit_matrix(const SkPoint pts[2]) {
    SkVector    vec = pts[1] - pts[0];
    SkScalar    mag = vec.length();
    SkScalar    inv = mag ? SkScalarInvert(mag) : 0;

    vec.scale(inv);
    SkMatrix matrix;
    matrix.setSinCos(-vec.fY, vec.fX, pts[0].fX, pts[0].fY);
    matrix.postTranslate(-pts[0].fX, -pts[0].fY);
    matrix.postScale(inv, inv);
    return matrix;
}

SkGLDevice::TexCache* SkGLDevice::setupGLPaintShader(const SkPaint& paint) {
    SkGL::SetPaint(paint);
    
    SkShader* shader = paint.getShader();
    if (NULL == shader) {
        return NULL;
    }
    
    if (!shader->setContext(this->accessBitmap(false), paint, this->matrix())) {
        return NULL;
    }
    
    SkBitmap bitmap;
    SkMatrix matrix;
    SkShader::TileMode tileModes[2];
    if (!shader->asABitmap(&bitmap, &matrix, tileModes)) {
        return NULL;
    }
    
    bitmap.lockPixels();
    if (!bitmap.readyToDraw()) {
        return NULL;
    }
    
    // see if we've already cached the bitmap from the shader
    SkPoint max;
    GLuint name;
    TexCache* cache = SkGLDevice::LockTexCache(bitmap, &name, &max);
    // the lock has already called glBindTexture for us
    SkGL::SetTexParams(paint.isFilterBitmap(), tileModes[0], tileModes[1]);
    
    // since our texture coords will be in local space, we wack the texture
    // matrix to map them back into 0...1 before we load it
    SkMatrix localM;
    if (shader->getLocalMatrix(&localM)) {
        SkMatrix inverse;
        if (localM.invert(&inverse)) {
            matrix.preConcat(inverse);
        }
    }
    
    matrix.postScale(max.fX / bitmap.width(), max.fY / bitmap.height());
    glMatrixMode(GL_TEXTURE);
    SkGL::LoadMatrix(matrix);
    glMatrixMode(GL_MODELVIEW);
    
    // since we're going to use a shader/texture, we don't want the color,
    // just its alpha
    SkGL::SetAlpha(paint.getAlpha());
    // report that we have setup the texture
    return cache;
}

std::unique_ptr<GrFragmentProcessor> GrTextureAdjuster::createFragmentProcessor(
        const SkMatrix& origTextureMatrix,
        const SkRect& constraintRect,
        FilterConstraint filterConstraint,
        bool coordsLimitedToConstraintRect,
        const GrSamplerState::Filter* filterOrNullForBicubic,
        SkColorSpace* dstColorSpace) {
    SkMatrix textureMatrix = origTextureMatrix;

    SkRect domain;
    GrSamplerState samplerState;
    if (filterOrNullForBicubic) {
        samplerState.setFilterMode(*filterOrNullForBicubic);
    }
    SkScalar scaleAdjust[2] = { 1.0f, 1.0f };
    sk_sp<GrTextureProxy> proxy(
            this->refTextureProxySafeForParams(samplerState, scaleAdjust));
    if (!proxy) {
        return nullptr;
    }
    // If we made a copy then we only copied the contentArea, in which case the new texture is all
    // content.
    if (proxy.get() != this->originalProxy()) {
        textureMatrix.postScale(scaleAdjust[0], scaleAdjust[1]);
    }

    DomainMode domainMode =
        DetermineDomainMode(constraintRect, filterConstraint, coordsLimitedToConstraintRect,
                            proxy.get(), filterOrNullForBicubic, &domain);
    if (kTightCopy_DomainMode == domainMode) {
        // TODO: Copy the texture and adjust the texture matrix (both parts need to consider
        // non-int constraint rect)
        // For now: treat as bilerp and ignore what goes on above level 0.

        // We only expect MIP maps to require a tight copy.
        SkASSERT(filterOrNullForBicubic &&
                 GrSamplerState::Filter::kMipMap == *filterOrNullForBicubic);
        static const GrSamplerState::Filter kBilerp = GrSamplerState::Filter::kBilerp;
        domainMode =
            DetermineDomainMode(constraintRect, filterConstraint, coordsLimitedToConstraintRect,
                                proxy.get(), &kBilerp, &domain);
        SkASSERT(kTightCopy_DomainMode != domainMode);
    }
    SkASSERT(kNoDomain_DomainMode == domainMode ||
             (domain.fLeft <= domain.fRight && domain.fTop <= domain.fBottom));
    GrPixelConfig config = proxy->config();
    auto fp = CreateFragmentProcessorForDomainAndFilter(std::move(proxy), textureMatrix,
                                                        domainMode, domain, filterOrNullForBicubic);
    return GrColorSpaceXformEffect::Make(std::move(fp), fColorSpace, config, dstColorSpace);
}

std::unique_ptr<GrFragmentProcessor> SkImageShader::asFragmentProcessor(
        const GrFPArgs& args) const {
    const auto lm = this->totalLocalMatrix(args.fPreLocalMatrix, args.fPostLocalMatrix);
    SkMatrix lmInverse;
    if (!lm->invert(&lmInverse)) {
        return nullptr;
    }

    GrSamplerState::WrapMode wrapModes[] = {tile_mode_to_wrap_mode(fTileModeX),
                                            tile_mode_to_wrap_mode(fTileModeY)};

    // Must set wrap and filter on the sampler before requesting a texture. In two places below
    // we check the matrix scale factors to determine how to interpret the filter quality setting.
    // This completely ignores the complexity of the drawVertices case where explicit local coords
    // are provided by the caller.
    bool doBicubic;
    GrSamplerState::Filter textureFilterMode = GrSkFilterQualityToGrFilterMode(
            args.fFilterQuality, *args.fViewMatrix, *lm,
            args.fContext->contextPriv().sharpenMipmappedTextures(), &doBicubic);
    GrSamplerState samplerState(wrapModes, textureFilterMode);
    sk_sp<SkColorSpace> texColorSpace;
    SkScalar scaleAdjust[2] = { 1.0f, 1.0f };
    sk_sp<GrTextureProxy> proxy(as_IB(fImage)->asTextureProxyRef(
            args.fContext, samplerState, args.fDstColorSpaceInfo->colorSpace(), &texColorSpace,
            scaleAdjust));
    if (!proxy) {
        return nullptr;
    }

    GrPixelConfig config = proxy->config();
    bool isAlphaOnly = GrPixelConfigIsAlphaOnly(config);

    lmInverse.postScale(scaleAdjust[0], scaleAdjust[1]);

    std::unique_ptr<GrFragmentProcessor> inner;
    if (doBicubic) {
        inner = GrBicubicEffect::Make(std::move(proxy), lmInverse, wrapModes);
    } else {
        inner = GrSimpleTextureEffect::Make(std::move(proxy), lmInverse, samplerState);
    }
    inner = GrColorSpaceXformEffect::Make(std::move(inner), texColorSpace.get(), config,
                                          args.fDstColorSpaceInfo->colorSpace());
    if (isAlphaOnly) {
        return inner;
    }
    return GrFragmentProcessor::MulChildByInputAlpha(std::move(inner));
}

static SkImage* makebm(SkBitmap* bm, int w, int h) {
    bm->allocN32Pixels(w, h);
    bm->eraseColor(SK_ColorTRANSPARENT);

    SkCanvas    canvas(*bm);

    SkScalar wScalar = SkIntToScalar(w);
    SkScalar hScalar = SkIntToScalar(h);

    SkPoint     pt = { wScalar / 2, hScalar / 2 };

    SkScalar    radius = 4 * SkMaxScalar(wScalar, hScalar);

    SkColor     colors[] = { SK_ColorRED, SK_ColorYELLOW,
                             SK_ColorGREEN, SK_ColorMAGENTA,
                             SK_ColorBLUE, SK_ColorCYAN,
                             SK_ColorRED};

    SkScalar    pos[] = {0,
                         SK_Scalar1 / 6,
                         2 * SK_Scalar1 / 6,
                         3 * SK_Scalar1 / 6,
                         4 * SK_Scalar1 / 6,
                         5 * SK_Scalar1 / 6,
                         SK_Scalar1};

    SkPaint     paint;
    SkRect rect = SkRect::MakeWH(wScalar, hScalar);
    SkMatrix mat = SkMatrix::I();
    for (int i = 0; i < 4; ++i) {
        paint.setShader(SkGradientShader::CreateRadial(
                        pt, radius,
                        colors, pos,
                        SK_ARRAY_COUNT(colors),
                        SkShader::kRepeat_TileMode,
                        0, &mat))->unref();
        canvas.drawRect(rect, paint);
        rect.inset(wScalar / 8, hScalar / 8);
        mat.postScale(SK_Scalar1 / 4, SK_Scalar1 / 4);
    }
    // Let backends know we won't change this, so they don't have to deep copy it defensively.
    bm->setImmutable();

    return image_from_bitmap(*bm);
}

static SkImage* makebm(SkCanvas* caller, int w, int h) {
    SkImageInfo info = SkImageInfo::MakeN32Premul(w, h);
    SkAutoTUnref<SkSurface> surface(caller->newSurface(info));
    if (nullptr == surface) {
        surface.reset(SkSurface::NewRaster(info));
    }
    SkCanvas* canvas = surface->getCanvas();

    const SkScalar wScalar = SkIntToScalar(w);
    const SkScalar hScalar = SkIntToScalar(h);

    const SkPoint     pt = { wScalar / 2, hScalar / 2 };

    const SkScalar    radius = 4 * SkMaxScalar(wScalar, hScalar);

    static const SkColor     colors[] = { SK_ColorRED, SK_ColorYELLOW,
                                          SK_ColorGREEN, SK_ColorMAGENTA,
                                          SK_ColorBLUE, SK_ColorCYAN,
                                          SK_ColorRED};

    static const SkScalar    pos[] = {0,
                                      SK_Scalar1 / 6,
                                      2 * SK_Scalar1 / 6,
                                      3 * SK_Scalar1 / 6,
                                      4 * SK_Scalar1 / 6,
                                      5 * SK_Scalar1 / 6,
                                      SK_Scalar1};

    SkASSERT(SK_ARRAY_COUNT(colors) == SK_ARRAY_COUNT(pos));
    SkPaint     paint;
    SkRect rect = SkRect::MakeWH(wScalar, hScalar);
    SkMatrix mat = SkMatrix::I();
    for (int i = 0; i < 4; ++i) {
        paint.setShader(SkGradientShader::CreateRadial(
                        pt, radius,
                        colors, pos,
                        SK_ARRAY_COUNT(colors),
                        SkShader::kRepeat_TileMode,
                        0, &mat))->unref();
        canvas->drawRect(rect, paint);
        rect.inset(wScalar / 8, hScalar / 8);
        mat.postScale(SK_Scalar1 / 4, SK_Scalar1 / 4);
    }
    return surface->newImageSnapshot();
}

SkMatrix Viewer::computeMatrix() {
    SkMatrix m;
    m.reset();

    if (fZoomLevel) {
        SkPoint center;
        //m = this->getLocalMatrix();//.invert(&m);
        m.mapXY(fZoomCenterX, fZoomCenterY, &center);
        SkScalar cx = center.fX;
        SkScalar cy = center.fY;

        m.setTranslate(-cx, -cy);
        m.postScale(fZoomScale, fZoomScale);
        m.postTranslate(cx, cy);
    }

    m.preConcat(fGesture.localM());
    m.preConcat(fGesture.globalM());

    return m;
}

    void onOnceBeforeDraw() override {
        SkPictureRecorder recorder;
        SkCanvas* pictureCanvas = recorder.beginRecording(kPictureSize, kPictureSize);
        draw_scene(pictureCanvas, kPictureSize);
        SkAutoTUnref<SkPicture> picture(recorder.endRecording());

        SkPoint offset = SkPoint::Make(100, 100);
        pictureCanvas = recorder.beginRecording(SkRect::MakeXYWH(offset.x(), offset.y(),
                                                                 kPictureSize, kPictureSize));
        pictureCanvas->translate(offset.x(), offset.y());
        draw_scene(pictureCanvas, kPictureSize);
        SkAutoTUnref<SkPicture> offsetPicture(recorder.endRecording());

        for (unsigned i = 0; i < SK_ARRAY_COUNT(tiles); ++i) {
            SkRect tile = SkRect::MakeXYWH(tiles[i].x * kPictureSize,
                                           tiles[i].y * kPictureSize,
                                           tiles[i].w * kPictureSize,
                                           tiles[i].h * kPictureSize);
            SkMatrix localMatrix;
            localMatrix.setTranslate(tiles[i].offsetX * kPictureSize,
                                     tiles[i].offsetY * kPictureSize);
            localMatrix.postScale(kFillSize / (2 * kPictureSize),
                                  kFillSize / (2 * kPictureSize));

            SkPicture* picturePtr = picture.get();
            SkRect* tilePtr = &tile;

            if (tile == SkRect::MakeWH(kPictureSize, kPictureSize)) {
                // When the tile == picture bounds, exercise the picture + offset path.
                picturePtr = offsetPicture.get();
                tilePtr = NULL;
            }

            fShaders[i].reset(SkShader::CreatePictureShader(picturePtr,
                                                            SkShader::kRepeat_TileMode,
                                                            SkShader::kRepeat_TileMode,
                                                            &localMatrix,
                                                            tilePtr));
        }
    }

    void onDraw(SkCanvas* canvas) override {
        SkIRect rects[2];
        rects[0] = SkIRect::MakeXYWH(0, 150, WIDTH, HEIGHT - 300);
        rects[1] = SkIRect::MakeXYWH(150, 0, WIDTH - 300, HEIGHT);
        SkRegion region;
        region.setRects(rects, 2);

        SkMatrix matrix;
        matrix.reset();
        matrix.setTranslate(WIDTH * .1f, HEIGHT * .1f);
        matrix.postScale(.8f, .8f);

        canvas->concat(matrix);

        SkPaint paint;
        paint.setImageFilter(
            SkAlphaThresholdFilter::Create(region, 0.2f, 0.7f))->unref();
        canvas->saveLayer(nullptr, &paint);
        paint.setAntiAlias(true);

        SkPaint rect_paint;
        rect_paint.setColor(0xFF0000FF);
        canvas->drawRect(SkRect::MakeXYWH(0, 0, WIDTH / 2, HEIGHT / 2),
                         rect_paint);
        rect_paint.setColor(0xBFFF0000);
        canvas->drawRect(SkRect::MakeXYWH(WIDTH / 2, 0, WIDTH / 2, HEIGHT / 2),
                         rect_paint);
        rect_paint.setColor(0x3F00FF00);
        canvas->drawRect(SkRect::MakeXYWH(0, HEIGHT / 2, WIDTH / 2, HEIGHT / 2),
                         rect_paint);
        rect_paint.setColor(0x00000000);
        canvas->drawRect(SkRect::MakeXYWH(WIDTH / 2, HEIGHT / 2, WIDTH / 2, HEIGHT / 2),
                         rect_paint);

        canvas->restore();
    }

//.........这里部分代码省略.........
    mat.reset();
    mat.setScale(SkIntToScalar(15), SkIntToScalar(15),
                 SkIntToScalar(2), SkIntToScalar(2));
    REPORTER_ASSERT(reporter, mat.isSimilarity());

    // scale with different size at a pivot point
    mat.reset();
    mat.setScale(SkIntToScalar(15), SkIntToScalar(20),
                 SkIntToScalar(2), SkIntToScalar(2));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // skew with same size
    mat.reset();
    mat.setSkew(SkIntToScalar(15), SkIntToScalar(15));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // skew with different size
    mat.reset();
    mat.setSkew(SkIntToScalar(15), SkIntToScalar(20));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // skew with same size at a pivot point
    mat.reset();
    mat.setSkew(SkIntToScalar(15), SkIntToScalar(15),
                SkIntToScalar(2), SkIntToScalar(2));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // skew with different size at a pivot point
    mat.reset();
    mat.setSkew(SkIntToScalar(15), SkIntToScalar(20),
                SkIntToScalar(2), SkIntToScalar(2));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // perspective x
    mat.reset();
    mat.setPerspX(SkScalarToPersp(SK_Scalar1 / 2));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // perspective y
    mat.reset();
    mat.setPerspY(SkScalarToPersp(SK_Scalar1 / 2));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

#ifdef SK_SCALAR_IS_FLOAT
    /* We bypass the following tests for SK_SCALAR_IS_FIXED build.
     * The long discussion can be found in this issue:
     *     http://codereview.appspot.com/5999050/
     * In short, we haven't found a perfect way to fix the precision
     * issue, i.e. the way we use tolerance in isSimilarityTransformation
     * is incorrect. The situation becomes worse in fixed build, so
     * we disabled rotation related tests for fixed build.
     */

    // rotate
    for (int angle = 0; angle < 360; ++angle) {
        mat.reset();
        mat.setRotate(SkIntToScalar(angle));
        REPORTER_ASSERT(reporter, mat.isSimilarity());
    }

    // see if there are any accumulated precision issues
    mat.reset();
    for (int i = 1; i < 360; i++) {
        mat.postRotate(SkIntToScalar(1));
    }
    REPORTER_ASSERT(reporter, mat.isSimilarity());

    // rotate + translate
    mat.reset();
    mat.setRotate(SkIntToScalar(30));
    mat.postTranslate(SkIntToScalar(10), SkIntToScalar(20));
    REPORTER_ASSERT(reporter, mat.isSimilarity());

    // rotate + uniform scale
    mat.reset();
    mat.setRotate(SkIntToScalar(30));
    mat.postScale(SkIntToScalar(2), SkIntToScalar(2));
    REPORTER_ASSERT(reporter, mat.isSimilarity());

    // rotate + non-uniform scale
    mat.reset();
    mat.setRotate(SkIntToScalar(30));
    mat.postScale(SkIntToScalar(3), SkIntToScalar(2));
    REPORTER_ASSERT(reporter, !mat.isSimilarity());
#endif

    // all zero
    mat.setAll(0, 0, 0, 0, 0, 0, 0, 0, 0);
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // all zero except perspective
    mat.setAll(0, 0, 0, 0, 0, 0, 0, 0, SK_Scalar1);
    REPORTER_ASSERT(reporter, !mat.isSimilarity());

    // scales zero, only skews
    mat.setAll(0, SK_Scalar1, 0,
               SK_Scalar1, 0, 0,
               0, 0, SkMatrix::I()[8]);
    REPORTER_ASSERT(reporter, mat.isSimilarity());
}

void GrStencilAndCoverTextContext::init(GrRenderTarget* rt,
                                        const GrClip& clip,
                                        const GrPaint& paint,
                                        const SkPaint& skPaint,
                                        size_t textByteLength,
                                        RenderMode renderMode,
                                        const SkMatrix& viewMatrix,
                                        const SkIRect& regionClipBounds) {
    GrTextContext::init(rt, clip, paint, skPaint, regionClipBounds);

    fContextInitialMatrix = viewMatrix;
    fViewMatrix = viewMatrix;
    fLocalMatrix = SkMatrix::I();

    const bool otherBackendsWillDrawAsPaths =
        SkDraw::ShouldDrawTextAsPaths(skPaint, fContextInitialMatrix);

    fUsingDeviceSpaceGlyphs = !otherBackendsWillDrawAsPaths &&
                              kMaxAccuracy_RenderMode == renderMode &&
                              SkToBool(fContextInitialMatrix.getType() &
                                       (SkMatrix::kScale_Mask | SkMatrix::kAffine_Mask));

    if (fUsingDeviceSpaceGlyphs) {
        // SkDraw::ShouldDrawTextAsPaths takes care of perspective transforms.
        SkASSERT(!fContextInitialMatrix.hasPerspective());

        // The whole shape (including stroke) will be baked into the glyph outlines. Make
        // NVPR just fill the baked shapes.
        fStroke = GrStrokeInfo(SkStrokeRec::kFill_InitStyle);

        fTextRatio = fTextInverseRatio = 1.0f;

        // Glyphs loaded by GPU path rendering have an inverted y-direction.
        SkMatrix m;
        m.setScale(1, -1);
        fViewMatrix = m;

        // Post-flip the initial matrix so we're left with just the flip after
        // the paint preConcats the inverse.
        m = fContextInitialMatrix;
        m.postScale(1, -1);
        if (!m.invert(&fLocalMatrix)) {
            SkDebugf("Not invertible!\n");
            return;
        }

        fGlyphCache = fSkPaint.detachCache(&fDeviceProperties, &fContextInitialMatrix,
                                           true /*ignoreGamma*/);
        fGlyphs = get_gr_glyphs(fContext, fGlyphCache->getScalerContext()->getTypeface(),
                                &fGlyphCache->getDescriptor(), fStroke);
    } else {
        // Don't bake strokes into the glyph outlines. We will stroke the glyphs
        // using the GPU instead. This is the fast path.
        fStroke = GrStrokeInfo(fSkPaint);
        fSkPaint.setStyle(SkPaint::kFill_Style);

        if (fStroke.isHairlineStyle()) {
            // Approximate hairline stroke.
            SkScalar strokeWidth = SK_Scalar1 /
                (SkVector::Make(fContextInitialMatrix.getScaleX(),
                                fContextInitialMatrix.getSkewY()).length());
            fStroke.setStrokeStyle(strokeWidth, false /*strokeAndFill*/);

        } else if (fSkPaint.isFakeBoldText() &&
#ifdef SK_USE_FREETYPE_EMBOLDEN
                   kMaxPerformance_RenderMode == renderMode &&
#endif
                   SkStrokeRec::kStroke_Style != fStroke.getStyle()) {

            // Instead of baking fake bold into the glyph outlines, do it with the GPU stroke.
            SkScalar fakeBoldScale = SkScalarInterpFunc(fSkPaint.getTextSize(),
                                                        kStdFakeBoldInterpKeys,
                                                        kStdFakeBoldInterpValues,
                                                        kStdFakeBoldInterpLength);
            SkScalar extra = SkScalarMul(fSkPaint.getTextSize(), fakeBoldScale);
            fStroke.setStrokeStyle(fStroke.needToApply() ? fStroke.getWidth() + extra : extra,
                                   true /*strokeAndFill*/);

            fSkPaint.setFakeBoldText(false);
        }

        bool canUseRawPaths;
        if (!fStroke.isDashed() && (otherBackendsWillDrawAsPaths ||
                                    kMaxPerformance_RenderMode == renderMode)) {
            // We can draw the glyphs from canonically sized paths.
            fTextRatio = fSkPaint.getTextSize() / SkPaint::kCanonicalTextSizeForPaths;
            fTextInverseRatio = SkPaint::kCanonicalTextSizeForPaths / fSkPaint.getTextSize();

            // Compensate for the glyphs being scaled by fTextRatio.
            if (!fStroke.isFillStyle()) {
                fStroke.setStrokeStyle(fStroke.getWidth() / fTextRatio,
                                       SkStrokeRec::kStrokeAndFill_Style == fStroke.getStyle());
            }

            fSkPaint.setLinearText(true);
            fSkPaint.setLCDRenderText(false);
            fSkPaint.setAutohinted(false);
            fSkPaint.setHinting(SkPaint::kNo_Hinting);
            fSkPaint.setSubpixelText(true);
            fSkPaint.setTextSize(SkIntToScalar(SkPaint::kCanonicalTextSizeForPaths));
//.........这里部分代码省略.........

static void generateMask(const SkMask& mask, const SkPath& path) {
    SkBitmap::Config config;
    SkPaint     paint;

    int srcW = mask.fBounds.width();
    int srcH = mask.fBounds.height();
    int dstW = srcW;
    int dstH = srcH;
    int dstRB = mask.fRowBytes;

    SkMatrix matrix;
    matrix.setTranslate(-SkIntToScalar(mask.fBounds.fLeft),
                        -SkIntToScalar(mask.fBounds.fTop));

    if (SkMask::kBW_Format == mask.fFormat) {
        config = SkBitmap::kA1_Config;
        paint.setAntiAlias(false);
    } else {
        config = SkBitmap::kA8_Config;
        paint.setAntiAlias(true);
        switch (mask.fFormat) {
            case SkMask::kA8_Format:
                break;
            case SkMask::kLCD16_Format:
            case SkMask::kLCD32_Format:
                // TODO: trigger off LCD orientation
                dstW *= 3;
                matrix.postScale(SkIntToScalar(3), SK_Scalar1);
                dstRB = 0;  // signals we need a copy
                break;
            default:
                SkDEBUGFAIL("unexpected mask format");
        }
    }

    SkRasterClip clip;
    clip.setRect(SkIRect::MakeWH(dstW, dstH));

    SkBitmap bm;
    bm.setConfig(config, dstW, dstH, dstRB);

    if (0 == dstRB) {
        bm.allocPixels();
        bm.lockPixels();
    } else {
        bm.setPixels(mask.fImage);
    }
    sk_bzero(bm.getPixels(), bm.getSafeSize());
    
    SkDraw  draw;
    sk_bzero(&draw, sizeof(draw));
    draw.fRC    = &clip;
    draw.fClip  = &clip.bwRgn();
    draw.fMatrix = &matrix;
    draw.fBitmap = &bm;
    draw.drawPath(path, paint);
    
    if (0 == dstRB) {
        switch (mask.fFormat) {
            case SkMask::kLCD16_Format:
                pack3xHToLCD16(bm, mask);
                break;
            case SkMask::kLCD32_Format:
                pack3xHToLCD32(bm, mask);
                break;
            default:
                SkDEBUGFAIL("bad format for copyback");
        }
    }
}

//.........这里部分代码省略.........
        if (!rect.isEmpty()) {
            paint.setColor(image->getColor(width - 1, 0));
            canvas.drawRect(rect, paint);
        }

        rect = SkRect::MakeLTRB(width, height, surfaceBBox.fRight,
                                surfaceBBox.fBottom);
        if (!rect.isEmpty()) {
            paint.setColor(image->getColor(width - 1, height - 1));
            canvas.drawRect(rect, paint);
        }

        rect = SkRect::MakeLTRB(surfaceBBox.fLeft, height, 0,
                                surfaceBBox.fBottom);
        if (!rect.isEmpty()) {
            paint.setColor(image->getColor(0, height - 1));
            canvas.drawRect(rect, paint);
        }
    }

    // Then expand the left, right, top, then bottom.
    if (tileModes[0] == SkShader::kClamp_TileMode) {
        SkIRect subset = SkIRect::MakeXYWH(0, 0, 1, height);
        if (surfaceBBox.fLeft < 0) {
            SkBitmap left;
            SkAssertResult(image->extractSubset(&left, subset));

            SkMatrix leftMatrix;
            leftMatrix.setScale(-surfaceBBox.fLeft, 1);
            leftMatrix.postTranslate(surfaceBBox.fLeft, 0);
            canvas.drawBitmapMatrix(left, leftMatrix);

            if (tileModes[1] == SkShader::kMirror_TileMode) {
                leftMatrix.postScale(SK_Scalar1, -SK_Scalar1);
                leftMatrix.postTranslate(0, 2 * height);
                canvas.drawBitmapMatrix(left, leftMatrix);
            }
            patternBBox.fLeft = 0;
        }

        if (surfaceBBox.fRight > width) {
            SkBitmap right;
            subset.offset(width - 1, 0);
            SkAssertResult(image->extractSubset(&right, subset));

            SkMatrix rightMatrix;
            rightMatrix.setScale(surfaceBBox.fRight - width, 1);
            rightMatrix.postTranslate(width, 0);
            canvas.drawBitmapMatrix(right, rightMatrix);

            if (tileModes[1] == SkShader::kMirror_TileMode) {
                rightMatrix.postScale(SK_Scalar1, -SK_Scalar1);
                rightMatrix.postTranslate(0, 2 * height);
                canvas.drawBitmapMatrix(right, rightMatrix);
            }
            patternBBox.fRight = surfaceBBox.width();
        }
    }

    if (tileModes[1] == SkShader::kClamp_TileMode) {
        SkIRect subset = SkIRect::MakeXYWH(0, 0, width, 1);
        if (surfaceBBox.fTop < 0) {
            SkBitmap top;
            SkAssertResult(image->extractSubset(&top, subset));

            SkMatrix topMatrix;