C++ SkXfermode::asMode方法代码示例

static void test_asMode(skiatest::Reporter* reporter) {
    for (int mode = 0; mode <= SkXfermode::kLastMode; mode++) {
        SkXfermode* xfer = SkXfermode::Create((SkXfermode::Mode) mode);

        SkXfermode::Mode reportedMode = ILLEGAL_MODE;
        REPORTER_ASSERT(reporter, reportedMode != mode);

        // test IsMode
        REPORTER_ASSERT(reporter, SkXfermode::AsMode(xfer, &reportedMode));
        REPORTER_ASSERT(reporter, reportedMode == mode);

        // repeat that test, but with asMode instead
        if (xfer) {
            reportedMode = (SkXfermode::Mode) -1;
            REPORTER_ASSERT(reporter, xfer->asMode(&reportedMode));
            REPORTER_ASSERT(reporter, reportedMode == mode);
            xfer->unref();
        } else {
            REPORTER_ASSERT(reporter, SkXfermode::kSrcOver_Mode == mode);
        }
    }

    SkXfermode* bogusXfer = new SkProcXfermode(bogusXfermodeProc);
    SkXfermode::Mode reportedMode = ILLEGAL_MODE;
    REPORTER_ASSERT(reporter, !bogusXfer->asMode(&reportedMode));
    REPORTER_ASSERT(reporter, reportedMode == ILLEGAL_MODE);
    REPORTER_ASSERT(reporter, !SkXfermode::AsMode(bogusXfer, &reportedMode));
    REPORTER_ASSERT(reporter, reportedMode == ILLEGAL_MODE);
    bogusXfer->unref();
}

SkXfermode::Mode CanvasRenderingContext2DState::globalComposite() const
{
    SkXfermode* xferMode = m_strokePaint.getXfermode();
    SkXfermode::Mode mode;
    if (!xferMode || !xferMode->asMode(&mode))
        return SkXfermode::kSrcOver_Mode;
    return mode;
}

static void test_asMode(skiatest::Reporter* reporter) {
    for (int mode = 0; mode <= SkXfermode::kLastMode; mode++) {
        SkXfermode* xfer = SkXfermode::Create((SkXfermode::Mode) mode);
        SkXfermode::Mode reportedMode = (SkXfermode::Mode) -1;
        REPORTER_ASSERT(reporter,
                        xfer != NULL || mode == SkXfermode::kSrcOver_Mode);
        if (xfer) {
          REPORTER_ASSERT(reporter, xfer->asMode(&reportedMode));
          REPORTER_ASSERT(reporter, reportedMode == mode);
          xfer->unref();
        }
    }

    SkXfermode* bogusXfer = new SkProcXfermode(bogusXfermodeProc);
    SkXfermode::Mode reportedMode = (SkXfermode::Mode) -1;
    REPORTER_ASSERT(reporter, !bogusXfer->asMode(&reportedMode));
    REPORTER_ASSERT(reporter, reportedMode == -1);
    bogusXfer->unref();
}

// We're only interested in some fields of the SkPaint, so we have a custom
// operator== function.
bool SkPDFGraphicState::GSCanonicalEntry::operator==(
        const SkPDFGraphicState::GSCanonicalEntry& gs) const {
    const SkPaint* a = fPaint;
    const SkPaint* b = gs.fPaint;
    SkASSERT(a != NULL);
    SkASSERT(b != NULL);

    if (SkColorGetA(a->getColor()) != SkColorGetA(b->getColor()) ||
           a->getStrokeCap() != b->getStrokeCap() ||
           a->getStrokeJoin() != b->getStrokeJoin() ||
           a->getStrokeWidth() != b->getStrokeWidth() ||
           a->getStrokeMiter() != b->getStrokeMiter()) {
        return false;
    }

    SkXfermode::Mode aXfermodeName = SkXfermode::kSrcOver_Mode;
    SkXfermode* aXfermode = a->getXfermode();
    if (aXfermode) {
        aXfermode->asMode(&aXfermodeName);
    }
    if (aXfermodeName < 0 || aXfermodeName > SkXfermode::kLastMode ||
            blend_mode_from_xfermode(aXfermodeName) == NULL) {
        aXfermodeName = SkXfermode::kSrcOver_Mode;
    }
    const char* aXfermodeString = blend_mode_from_xfermode(aXfermodeName);
    SkASSERT(aXfermodeString != NULL);

    SkXfermode::Mode bXfermodeName = SkXfermode::kSrcOver_Mode;
    SkXfermode* bXfermode = b->getXfermode();
    if (bXfermode) {
        bXfermode->asMode(&bXfermodeName);
    }
    if (bXfermodeName < 0 || bXfermodeName > SkXfermode::kLastMode ||
            blend_mode_from_xfermode(bXfermodeName) == NULL) {
        bXfermodeName = SkXfermode::kSrcOver_Mode;
    }
    const char* bXfermodeString = blend_mode_from_xfermode(bXfermodeName);
    SkASSERT(bXfermodeString != NULL);

    return strcmp(aXfermodeString, bXfermodeString) == 0;
}

    static bool PaintMayAffectTransparentBlack(const SkPaint* paint) {
        if (paint) {
            // FIXME: this is very conservative
            if (paint->getImageFilter() || paint->getColorFilter()) {
                return true;
            }

            // Unusual Xfermodes require us to process a saved layer
            // even with operations outisde the clip.
            // For example, DstIn is used by masking layers.
            // https://code.google.com/p/skia/issues/detail?id=1291
            // https://crbug.com/401593
            SkXfermode* xfermode = paint->getXfermode();
            SkXfermode::Mode mode;
            // SrcOver is ok, and is also the common case with a NULL xfermode.
            // So we should make that the fast path and bypass the mode extraction
            // and test.
            if (xfermode && xfermode->asMode(&mode)) {
                switch (mode) {
                    // For each of the following transfer modes, if the source
                    // alpha is zero (our transparent black), the resulting
                    // blended alpha is not necessarily equal to the original
                    // destination alpha.
                    case SkXfermode::kClear_Mode:
                    case SkXfermode::kSrc_Mode:
                    case SkXfermode::kSrcIn_Mode:
                    case SkXfermode::kDstIn_Mode:
                    case SkXfermode::kSrcOut_Mode:
                    case SkXfermode::kDstATop_Mode:
                    case SkXfermode::kModulate_Mode:
                        return true;
                        break;
                    default:
                        break;
                }
            }
        }
        return false;
    }