pb_cspace.lua

return {init=function(_,_,_,_,_,_)
    local function rgb_to_oklab(r,g,b)
        local l = (r*0.4122214708 + g*0.5363325363 + b*0.0514459929)^0.3333333
        local m = (r*0.2119034982 + g*0.6806995451 + b*0.1073969566)^0.3333333
        local s = (r*0.0883024619 + g*0.2817188376 + b*0.6299787005)^0.3333333

        return  l*0.2104542553 + m*0.7936177850 - s*0.0040720468,
                l*1.9779984951 - m*2.4285922050 + s*0.4505937099,
                l*0.0259040371 + m*0.7827717662 - s*0.8086757660
    end

    local function rgb_to_xyz(r,g,b)
        if r > 0.04045 then r = ((r+0.055)/1.055)^2.4
        else r = r/12.92 end

        if g > 0.04045 then g = ((g+0.055)/1.055)^2.4
        else g = g/12.92 end

        if b > 0.04045 then b = ((b+0.055)/1.055)^2.4
        else b = b/12.92 end

        return  r*0.4124 + g*0.3576 + b*0.1805,
                r*0.2126 + g*0.7152 + b*0.0722,
                r*0.0193 + g*0.1192 + b*0.9505
    end

    local cielab_const = 16 / 116
    local function rgb_to_cielab(r,g,b)
        local x,y,z = rgb_to_xyz(r,g,b)

        local spc_x = x / 94.811
        local spc_y = y / 100
        local spc_z = z / 107.304

        if spc_x > 0.008856 then spc_x = spc_x^0.3333333
        else spc_x = 7.787*spc_x + cielab_const end

        if spc_y > 0.008856 then spc_y = spc_y^0.3333333
        else spc_y = 7.787*spc_y + cielab_const end

        if spc_z > 0.008856 then spc_z = spc_z^0.3333333
        else spc_z = 7.787*spc_z + cielab_const end

        return  (16*spc_y) - 16,
                50*(spc_x-spc_y),
                20*(spc_y-spc_z)
    end

    local function rgb_to_rgb(r,g,b)
        return r,g,b
    end

    return {cspace = {
        cielab = rgb_to_cielab,
        oklab  = rgb_to_oklab,
        rgb    = rgb_to_rgb,
        xyz    = rgb_to_xyz,
    }},{}
end,
    id         = "PB_MODULE:cspace",
    name       = "PB_ColorSpace",
    author     = "9551",
    contact    = "https://devvie.cc/contact",
    report_msg = "\n__name: module error, report issues at\n-> __contact"
}