Function radiusToSigma

snap_drawing/src/snap_drawing/cpp/Layers/ImageLayer.cpp:36–38

static const SkScalar kBlurSigmaScale = 0.57735f;

static Scalar radiusToSigma(Scalar radius) {
    return radius > 0 ? kBlurSigmaScale * radius + 0.5f : 0.0f;
}

void ImageLayer::onDraw(DrawingContext& drawingContext) {
    Layer::onDraw(drawingContext);