C++ SkPaint::isSrcOver方法代码示例

SkRGB16_Black_Blitter::SkRGB16_Black_Blitter(const SkPixmap& device, const SkPaint& paint)
    : INHERITED(device, paint) {
    SkASSERT(paint.getShader() == nullptr);
    SkASSERT(paint.getColorFilter() == nullptr);
    SkASSERT(paint.isSrcOver());
    SkASSERT(paint.getColor() == SK_ColorBLACK);
}

void SkBaseDevice::drawImageLattice(const SkImage* image,
                                    const SkCanvas::Lattice& lattice, const SkRect& dst,
                                    const SkPaint& paint) {
    SkLatticeIter iter(lattice, dst);

    SkRect srcR, dstR;
    SkColor c;
    bool isFixedColor = false;
    const SkImageInfo info = SkImageInfo::Make(1, 1, kBGRA_8888_SkColorType, kUnpremul_SkAlphaType);

    while (iter.next(&srcR, &dstR, &isFixedColor, &c)) {
          if (isFixedColor || (srcR.width() <= 1.0f && srcR.height() <= 1.0f &&
                               image->readPixels(info, &c, 4, srcR.fLeft, srcR.fTop))) {
              // Fast draw with drawRect, if this is a patch containing a single color
              // or if this is a patch containing a single pixel.
              if (0 != c || !paint.isSrcOver()) {
                   SkPaint paintCopy(paint);
                   int alpha = SkAlphaMul(SkColorGetA(c), SkAlpha255To256(paint.getAlpha()));
                   paintCopy.setColor(SkColorSetA(c, alpha));
                   this->drawRect(dstR, paintCopy);
              }
        } else {
            this->drawImageRect(image, &srcR, dstR, paint, SkCanvas::kStrict_SrcRectConstraint);
        }
    }
}

bool SkBitmapDevice::onShouldDisableLCD(const SkPaint& paint) const {
    if (kN32_SkColorType != fBitmap.colorType() ||
        paint.getRasterizer() ||
        paint.getPathEffect() ||
        paint.isFakeBoldText() ||
        paint.getStyle() != SkPaint::kFill_Style ||
        !paint.isSrcOver())
    {
        return true;
    }
    return false;
}

SkA8_Coverage_Blitter::SkA8_Coverage_Blitter(const SkPixmap& device,
                             const SkPaint& paint) : SkRasterBlitter(device) {
    SkASSERT(nullptr == paint.getShader());
    SkASSERT(paint.isSrcOver());
    SkASSERT(nullptr == paint.getColorFilter());
}

//.........这里部分代码省略.........

            // The above may return null if compose results in a pass through of the prim color.
            if (shaderFP) {
                grPaint->addColorFragmentProcessor(std::move(shaderFP));
            }

            // We can ignore origColor here - alpha is unchanged by gamma
            GrColor paintAlpha = SkColorAlphaToGrColor(skPaint.getColor());
            if (GrColor_WHITE != paintAlpha) {
                // No gamut conversion - paintAlpha is a (linear) alpha value, splatted to all
                // color channels. It's value should be treated as the same in ANY color space.
                grPaint->addColorFragmentProcessor(GrConstColorProcessor::Make(
                    GrColor4f::FromGrColor(paintAlpha),
                    GrConstColorProcessor::InputMode::kModulateRGBA));
            }
        } else {
            // The shader's FP sees the paint unpremul color
            grPaint->setColor4f(origColor);
            grPaint->addColorFragmentProcessor(std::move(shaderFP));
        }
    } else {
        if (primColorMode) {
            // There is a blend between the primitive color and the paint color. The blend considers
            // the opaque paint color. The paint's alpha is applied to the post-blended color.
            auto processor = GrConstColorProcessor::Make(origColor.opaque(),
                                                         GrConstColorProcessor::InputMode::kIgnore);
            processor = GrXfermodeFragmentProcessor::MakeFromSrcProcessor(std::move(processor),
                                                                          *primColorMode);
            if (processor) {
                grPaint->addColorFragmentProcessor(std::move(processor));
            }

            grPaint->setColor4f(origColor.opaque());

            // We can ignore origColor here - alpha is unchanged by gamma
            GrColor paintAlpha = SkColorAlphaToGrColor(skPaint.getColor());
            if (GrColor_WHITE != paintAlpha) {
                // No gamut conversion - paintAlpha is a (linear) alpha value, splatted to all
                // color channels. It's value should be treated as the same in ANY color space.
                grPaint->addColorFragmentProcessor(GrConstColorProcessor::Make(
                    GrColor4f::FromGrColor(paintAlpha),
                    GrConstColorProcessor::InputMode::kModulateRGBA));
            }
        } else {
            // No shader, no primitive color.
            grPaint->setColor4f(origColor.premul());
            applyColorFilterToPaintColor = true;
        }
    }

    SkColorFilter* colorFilter = skPaint.getColorFilter();
    if (colorFilter) {
        if (applyColorFilterToPaintColor) {
            // If we're in legacy mode, we *must* avoid using the 4f version of the color filter,
            // because that will combine with the linearized version of the stored color.
            if (colorSpaceInfo.isGammaCorrect()) {
                grPaint->setColor4f(GrColor4f::FromSkColor4f(
                    colorFilter->filterColor4f(origColor.toSkColor4f())).premul());
            } else {
                grPaint->setColor4f(SkColorToPremulGrColor4fLegacy(
                        colorFilter->filterColor(skPaint.getColor())));
            }
        } else {
            auto cfFP = colorFilter->asFragmentProcessor(context, colorSpaceInfo);
            if (cfFP) {
                grPaint->addColorFragmentProcessor(std::move(cfFP));
            } else {
                return false;
            }
        }
    }

    SkMaskFilterBase* maskFilter = as_MFB(skPaint.getMaskFilter());
    if (maskFilter) {
        if (auto mfFP = maskFilter->asFragmentProcessor(fpArgs)) {
            grPaint->addCoverageFragmentProcessor(std::move(mfFP));
        }
    }

    // When the xfermode is null on the SkPaint (meaning kSrcOver) we need the XPFactory field on
    // the GrPaint to also be null (also kSrcOver).
    SkASSERT(!grPaint->getXPFactory());
    if (!skPaint.isSrcOver()) {
        grPaint->setXPFactory(SkBlendMode_AsXPFactory(skPaint.getBlendMode()));
    }

#ifndef SK_IGNORE_GPU_DITHER
    // Conservative default, in case GrPixelConfigToColorType() fails.
    SkColorType ct = SkColorType::kRGB_565_SkColorType;
    GrPixelConfigToColorType(colorSpaceInfo.config(), &ct);
    if (SkPaintPriv::ShouldDither(skPaint, ct) && grPaint->numColorFragmentProcessors() > 0 &&
        !colorSpaceInfo.isGammaCorrect()) {
        auto ditherFP = GrDitherEffect::Make(colorSpaceInfo.config());
        if (ditherFP) {
            grPaint->addColorFragmentProcessor(std::move(ditherFP));
        }
    }
#endif
    return true;
}