C++ Builder::addLayer方法代码示例

    sk_sp<SkDrawLooper> createLooper(SkScalar xOff, SkScalar sigma) {
        SkLayerDrawLooper::Builder looperBuilder;

        //-----------------------------------------------
        SkLayerDrawLooper::LayerInfo info;

        // TODO: add a color filter to better match what is seen in the wild
        info.fPaintBits = /* SkLayerDrawLooper::kColorFilter_Bit |*/
                          SkLayerDrawLooper::kMaskFilter_Bit;
        info.fColorMode = SkXfermode::kDst_Mode;
        info.fOffset.set(xOff, 0);
        info.fPostTranslate = false;

        SkPaint* paint = looperBuilder.addLayer(info);

        paint->setMaskFilter(SkBlurMaskFilter::Make(kNormal_SkBlurStyle, sigma,
                                                    SkBlurMaskFilter::kHighQuality_BlurFlag));

        //-----------------------------------------------
        info.fPaintBits = 0;
        info.fOffset.set(0, 0);

        paint = looperBuilder.addLayer(info);
        return looperBuilder.detach();
    }

    void init() {
        if (fLooper) return;

        constexpr struct {
            SkColor         fColor;
            SkPaint::Style  fStyle;
            SkScalar        fWidth;
            SkScalar        fOffset;
            SkScalar        fBlur;
        } gParams[] = {
            { SK_ColorWHITE, SkPaint::kStroke_Style, SkIntToScalar(1)*3/4, 0, 0 },
            { SK_ColorRED, SkPaint::kStroke_Style, SkIntToScalar(4), 0, 0 },
            { SK_ColorBLUE, SkPaint::kFill_Style, 0, 0, 0 },
            { 0x88000000, SkPaint::kFill_Style, 0, SkIntToScalar(10), SkIntToScalar(3) }
        };

        SkLayerDrawLooper::Builder looperBuilder;

        SkLayerDrawLooper::LayerInfo info;
        info.fPaintBits = SkLayerDrawLooper::kStyle_Bit | SkLayerDrawLooper::kMaskFilter_Bit;
        info.fColorMode = SkBlendMode::kSrc;

        for (size_t i = 0; i < SK_ARRAY_COUNT(gParams); i++) {
            info.fOffset.set(gParams[i].fOffset, gParams[i].fOffset);
            SkPaint* paint = looperBuilder.addLayer(info);
            paint->setColor(gParams[i].fColor);
            paint->setStyle(gParams[i].fStyle);
            paint->setStrokeWidth(gParams[i].fWidth);
            if (gParams[i].fBlur > 0) {
                paint->setMaskFilter(SkBlurMaskFilter::Make(kNormal_SkBlurStyle,
                                         SkBlurMask::ConvertRadiusToSigma(gParams[i].fBlur)));
            }
        }
        fLooper = looperBuilder.detach();
    }

static void test_frontToBack(skiatest::Reporter* reporter) {
    SkLayerDrawLooper::Builder looperBuilder;
    SkLayerDrawLooper::LayerInfo layerInfo;

    // Add the front layer, with the defaults.
    (void)looperBuilder.addLayer(layerInfo);

    // Add the back layer, with some layer info set.
    layerInfo.fOffset.set(10.0f, 20.0f);
    layerInfo.fPaintBits |= SkLayerDrawLooper::kXfermode_Bit;
    SkPaint* layerPaint = looperBuilder.addLayer(layerInfo);
    layerPaint->setBlendMode(SkBlendMode::kSrc);

    FakeDevice device;
    SkCanvas canvas(&device);
    SkPaint paint;
    auto looper(looperBuilder.detach());
    SkArenaAlloc alloc{48};
    SkDrawLooper::Context* context = looper->makeContext(&canvas, &alloc);

    // The back layer should come first.
    REPORTER_ASSERT(reporter, context->next(&canvas, &paint));
    REPORTER_ASSERT(reporter, paint.getBlendMode() == SkBlendMode::kSrc);
    canvas.drawRect(SkRect::MakeWH(50.0f, 50.0f), paint);
    REPORTER_ASSERT(reporter, 10.0f == device.fLastMatrix.getTranslateX());
    REPORTER_ASSERT(reporter, 20.0f == device.fLastMatrix.getTranslateY());
    paint.reset();

    // Then the front layer.
    REPORTER_ASSERT(reporter, context->next(&canvas, &paint));
    REPORTER_ASSERT(reporter, paint.getBlendMode() == SkBlendMode::kSrcOver);
    canvas.drawRect(SkRect::MakeWH(50.0f, 50.0f), paint);
    REPORTER_ASSERT(reporter, 0.0f == device.fLastMatrix.getTranslateX());
    REPORTER_ASSERT(reporter, 0.0f == device.fLastMatrix.getTranslateY());

    // Only two layers were added, so that should be the end.
    REPORTER_ASSERT(reporter, !context->next(&canvas, &paint));
}

sk_sp<SkDrawLooper> SkBlurDrawLooper::Make(SkColor color, SkScalar sigma, SkScalar dx, SkScalar dy)
{
    sk_sp<SkMaskFilter> blur = nullptr;
    if (sigma > 0.0f) {
        blur = SkMaskFilter::MakeBlur(kNormal_SkBlurStyle, sigma, true);
    }

    SkLayerDrawLooper::Builder builder;

    // First layer
    SkLayerDrawLooper::LayerInfo defaultLayer;
    builder.addLayer(defaultLayer);

    // Blur layer
    SkLayerDrawLooper::LayerInfo blurInfo;
    blurInfo.fColorMode = SkBlendMode::kSrc;
    blurInfo.fPaintBits = SkLayerDrawLooper::kMaskFilter_Bit;
    blurInfo.fOffset = SkVector::Make(dx, dy);
    SkPaint* paint = builder.addLayer(blurInfo);
    paint->setMaskFilter(std::move(blur));
    paint->setColor(color);

    return builder.detach();
}

    // Create a 1-tier drawlooper
    sk_sp<SkDrawLooper> create1Looper(SkScalar xOff, SkScalar yOff, SkColor color) {
        SkLayerDrawLooper::Builder looperBuilder;
        SkLayerDrawLooper::LayerInfo info;

        info.fPaintBits = SkLayerDrawLooper::kColorFilter_Bit |
                          SkLayerDrawLooper::kMaskFilter_Bit;
        info.fColorMode = (SK_XFERMODE_MODE_PARAM)SkBlendMode::kSrc;
        info.fOffset.set(xOff, yOff);
        info.fPostTranslate = false;

        SkPaint* paint = looperBuilder.addLayer(info);

        paint->setMaskFilter(MakeBlur());

        paint->setColorFilter(SkColorFilter::MakeModeFilter(color, SkBlendMode::kSrcIn));

        return looperBuilder.detach();
    }

    // Create a 1-tier drawlooper
    sk_sp<SkDrawLooper> create1Looper(SkScalar xOff, SkScalar yOff, SkColor color) {
        SkLayerDrawLooper::Builder looperBuilder;
        SkLayerDrawLooper::LayerInfo info;

        info.fPaintBits = SkLayerDrawLooper::kColorFilter_Bit |
                          SkLayerDrawLooper::kMaskFilter_Bit;
        info.fColorMode = SkXfermode::kSrc_Mode;
        info.fOffset.set(xOff, yOff);
        info.fPostTranslate = false;

        SkPaint* paint = looperBuilder.addLayer(info);

        paint->setMaskFilter(this->createBlur())->unref();

        paint->setColorFilter(SkColorFilter::MakeModeFilter(color, SkXfermode::kSrcIn_Mode));

        return looperBuilder.detach();
    }

    // Create a 4-tier draw looper
    sk_sp<SkDrawLooper> create4Looper(SkScalar xOff, SkScalar yOff) {
        SkLayerDrawLooper::Builder looperBuilder;
        SkLayerDrawLooper::LayerInfo info;

        info.fPaintBits = SkLayerDrawLooper::kColorFilter_Bit |
                          SkLayerDrawLooper::kMaskFilter_Bit;
        info.fColorMode = SkXfermode::kSrc_Mode;
        info.fPostTranslate = false;

        SkPaint* paint;

        for (int i = 3; i >= 0; --i) {
            info.fOffset.set(xOff+gBlurOffsets[i].fX, yOff+gBlurOffsets[i].fY);
            paint = looperBuilder.addLayer(info);

            paint->setMaskFilter(this->createBlur())->unref();

            SkColorFilter* cf = SkColorFilter::CreateModeFilter(gColors[i], SkXfermode::kSrcIn_Mode);
            paint->setColorFilter(cf)->unref();
        }

        return looperBuilder.detach();
    }

static sk_sp<SkDrawLooper> setupLooper(SkLayerDrawLooper::BitFlags bits,
                                       LooperProc proc,
                                       const LooperSettings settings[],
                                       size_t size) {
    SkLayerDrawLooper::Builder looperBuilder;

    SkLayerDrawLooper::LayerInfo info;
    info.fPaintBits = bits;

    info.fColorMode = (SK_XFERMODE_MODE_PARAM)SkBlendMode::kSrc;

    for (size_t i = 0; i < size; i++) {
        info.fOffset.set(settings[i].fOffset, settings[i].fOffset);
        SkPaint* paint = looperBuilder.addLayer(info);
        paint->setBlendMode(settings[i].fMode);
        paint->setColor(settings[i].fColor);
        paint->setStyle(settings[i].fStyle);
        paint->setStrokeWidth(settings[i].fWidth);
        if (settings[i].fEffect) {
            (*proc)(paint);
        }
    }
    return looperBuilder.detach();
}

static SkLayerDrawLooper* setupLooper(SkLayerDrawLooper::BitFlags bits,
                                      LooperProc proc,
                                      const LooperSettings settings[],
                                      size_t size) {
    SkLayerDrawLooper::Builder looperBuilder;

    SkLayerDrawLooper::LayerInfo info;
    info.fPaintBits = bits;

    info.fColorMode = SkXfermode::kSrc_Mode;

    for (size_t i = 0; i < size; i++) {
        info.fOffset.set(settings[i].fOffset, settings[i].fOffset);
        SkPaint* paint = looperBuilder.addLayer(info);
        paint->setXfermodeMode(settings[i].fMode);
        paint->setColor(settings[i].fColor);
        paint->setStyle(settings[i].fStyle);
        paint->setStrokeWidth(settings[i].fWidth);
        if (settings[i].fEffect) {
            (*proc)(paint);
        }
    }
    return looperBuilder.detachLooper();
}