// A version of Matrix which operates in HSLA space instead of RGBA.
    // I.e. HSLA-to-RGBA(Matrix(RGBA-to-HSLA(input))).
    static sk_sp<SkColorFilter> HSLAMatrix(const SkColorMatrix&);
    static sk_sp<SkColorFilter> HSLAMatrix(const float rowMajor[20]);

    static sk_sp<SkColorFilter> LinearToSRGBGamma();
    static sk_sp<SkColorFilter> SRGBToLinearGamma();
    static sk_sp<SkColorFilter> Lerp(float t, sk_sp<SkColorFilter> dst, sk_sp<SkColorFilter> src);

    // Runs the child filter in a different working color format than usual (premul in
    // destination surface's color space), with all inputs and outputs expressed in this format.
    // Each non-null {tf,gamut,at} parameter overrides that particular aspect of the color format.
    static sk_sp<SkColorFilter> WithWorkingFormat(sk_sp<SkColorFilter>          child,
                                                  const skcms_TransferFunction* tf,
                                                  const skcms_Matrix3x3*        gamut,
                                                  const SkAlphaType*            at);