buildSourceMatrixQ16()

bool fl::buildSourceMatrixQ16	(	const RgbPrimaries &	primaries,
		SourceMatrixQ16 *	out )

Quantize the source matrix for primaries.

False if the primaries are collinear, which makes the primary matrix singular.

Definition at line 57 of file source_xyz.cpp.hpp.

                                                             {
    if (out == nullptr) {
        return false;
    }
    // In s16.16 throughout (FastLED#4458): the same construction as
    // `colorimetric_response::build_source_matrix` -- primaries' XYZ at unit
    // luminance as columns P, scaled per column by k = P^-1 W so that full
    // RGB lands on the white -- with no float operation on the way.
    i32 xy_r[2];
    i32 xy_g[2];
    i32 xy_b[2];
    i32 xy_w[2];
    if (!sourceChromaticityQ16(primaries.red, xy_r) ||
        !sourceChromaticityQ16(primaries.green, xy_g) ||
        !sourceChromaticityQ16(primaries.blue, xy_b) ||
        !sourceChromaticityQ16(primaries.white, xy_w)) {
        return false;
    }
    if (!sourcePrimariesEncloseAreaQ16(xy_r, xy_g, xy_b)) {
        return false;
    }
    i64 red[3];
    i64 green[3];
    i64 blue[3];
    i64 white[3];
    if (!detail::xyzColumnQ16(xy_r, kSourceQ16One, red) ||
        !detail::xyzColumnQ16(xy_g, kSourceQ16One, green) ||
        !detail::xyzColumnQ16(xy_b, kSourceQ16One, blue) ||
        !detail::xyzColumnQ16(xy_w, kSourceQ16One, white)) {
        return false;
    }
    const i32 primaries_xyz[3][3] = {
        {static_cast<i32>(red[0]), static_cast<i32>(green[0]), static_cast<i32>(blue[0])},
        {static_cast<i32>(red[1]), static_cast<i32>(green[1]), static_cast<i32>(blue[1])},
        {static_cast<i32>(red[2]), static_cast<i32>(green[2]), static_cast<i32>(blue[2])},
    };
    i32 inverse[3][3];
    if (!invert3x3Q16(primaries_xyz, inverse)) {
        return false;
    }
    const i32 white_xyz[3] = {static_cast<i32>(white[0]), static_cast<i32>(white[1]),
                              static_cast<i32>(white[2])};
    i32 k[3];
    for (int i = 0; i < 3; ++i) {
        k[i] = detail::dotRowQ16(inverse[i], white_xyz);
    }
    for (int row = 0; row < 3; ++row) {
        for (int col = 0; col < 3; ++col) {
            const i64 product = static_cast<i64>(primaries_xyz[row][col]) * k[col];
            out->m[row][col] = static_cast<i32>(
                detail::roundedDivideQ16(product, kSourceQ16One));
        }
    }
    return true;
}

References fl::detail::dotRowQ16(), FL_NO_EXCEPT, invert3x3Q16(), fl::detail::roundedDivideQ16(), and fl::detail::xyzColumnQ16().

Referenced by buildStreamingPipelineQ16().

Here is the call graph for this function:

Here is the caller graph for this function: