C++ (Cpp) GrShaderCaps::shaderDerivativeSupport Examples

Example #1

// Will the given round rect look good if we use HW derivatives?
static bool can_use_hw_derivatives_with_coverage(
        const GrShaderCaps& shaderCaps, const SkMatrix& viewMatrix, const SkRRect& rrect) {
    if (!shaderCaps.shaderDerivativeSupport()) {
        return false;
    }

    Sk2f x = Sk2f(viewMatrix.getScaleX(), viewMatrix.getSkewX());
    Sk2f y = Sk2f(viewMatrix.getSkewY(), viewMatrix.getScaleY());
    Sk2f devScale = (x*x + y*y).sqrt();
    switch (rrect.getType()) {
        case SkRRect::kEmpty_Type:
        case SkRRect::kRect_Type:
            return true;

        case SkRRect::kOval_Type:
        case SkRRect::kSimple_Type:
            return can_use_hw_derivatives_with_coverage(devScale, rrect.getSimpleRadii());

        case SkRRect::kNinePatch_Type: {
            Sk2f r0 = Sk2f::Load(SkRRectPriv::GetRadiiArray(rrect));
            Sk2f r1 = Sk2f::Load(SkRRectPriv::GetRadiiArray(rrect) + 2);
            Sk2f minRadii = Sk2f::Min(r0, r1);
            Sk2f maxRadii = Sk2f::Max(r0, r1);
            return can_use_hw_derivatives_with_coverage(devScale, Sk2f(minRadii[0], maxRadii[1])) &&
                   can_use_hw_derivatives_with_coverage(devScale, Sk2f(maxRadii[0], minRadii[1]));
        }

        case SkRRect::kComplex_Type: {
            for (int i = 0; i < 4; ++i) {
                auto corner = static_cast<SkRRect::Corner>(i);
                if (!can_use_hw_derivatives_with_coverage(devScale, rrect.radii(corner))) {
                    return false;
                }
            }
            return true;
        }
    }
    SK_ABORT("Invalid round rect type.");
    return false;  // Add this return to keep GCC happy.
}

Example #2

File: GrTextUtils.cpp Project: YangchenVR/skia

bool GrTextUtils::CanDrawAsDistanceFields(const SkPaint& skPaint, const SkMatrix& viewMatrix,
                                          const SkSurfaceProps& props, const GrShaderCaps& caps) {
    // TODO: support perspective (need getMaxScale replacement)
    if (viewMatrix.hasPerspective()) {
        return false;
    }

    SkScalar maxScale = viewMatrix.getMaxScale();
    SkScalar scaledTextSize = maxScale*skPaint.getTextSize();
    // Hinted text looks far better at small resolutions
    // Scaling up beyond 2x yields undesireable artifacts
    if (scaledTextSize < kMinDFFontSize ||
        scaledTextSize > kLargeDFFontLimit) {
        return false;
    }

    bool useDFT = props.isUseDeviceIndependentFonts();
#if SK_FORCE_DISTANCE_FIELD_TEXT
    useDFT = true;
#endif

    if (!useDFT && scaledTextSize < kLargeDFFontSize) {
        return false;
    }

    // rasterizers and mask filters modify alpha, which doesn't
    // translate well to distance
    if (skPaint.getRasterizer() || skPaint.getMaskFilter() || !caps.shaderDerivativeSupport()) {
        return false;
    }

    // TODO: add some stroking support
    if (skPaint.getStyle() != SkPaint::kFill_Style) {
        return false;
    }

    return true;
}