init (again)

i accidentally [doxxed myself](https://github.com/JannisX11/blockbench/issues/1322), thanks blockbench!

scripts/libs/oklab.lua

@@ -0,0 +1,113 @@
+local lib = {}
+
+---@param x number
+---@return number
+local function fromLinear(x)
+    if x >= 0.0031308 then
+        return 1.055 * math.pow(x, 1.0/2.4) - 0.055
+    else
+        return 12.92 * x
+    end
+end
+
+---@param x number
+---@return number
+local function toLinear(x)
+    if x >= 0.04045 then
+        return math.pow((x + 0.055)/(1 + 0.055), 2.4)
+    else
+        return x / 12.92
+    end
+end
+
+---Converts from sRGB to Linear sRGB
+---@param color Vector3
+---@return Vector3
+function lib.srgbToLinear(color)
+    return vec(toLinear(color.x), toLinear(color.y), toLinear(color.z))
+end
+
+---Converts from Linear sRGB to sRGB
+---@param color Vector3
+---@return Vector3
+function lib.linearToSrgb(color)
+    return vec(fromLinear(color.x), fromLinear(color.y), fromLinear(color.z))
+end
+
+---Converts from Linear sRGB to OKLAB
+---@param color Vector3
+---@return Vector3
+function lib.linearToOklab(color)
+    local l = 0.4122214708 * color.r + 0.5363325363 * color.g + 0.0514459929 * color.b
+	local m = 0.2119034982 * color.r + 0.6806995451 * color.g + 0.1073969566 * color.b
+	local s = 0.0883024619 * color.r + 0.2817188376 * color.g + 0.6299787005 * color.b
+
+    local l_ = math.pow(l, 1/3)
+    local m_ = math.pow(m, 1/3)
+    local s_ = math.pow(s, 1/3)
+
+    return vec(
+        0.2104542553*l_ + 0.7936177850*m_ - 0.0040720468*s_,
+        1.9779984951*l_ - 2.4285922050*m_ + 0.4505937099*s_,
+        0.0259040371*l_ + 0.7827717662*m_ - 0.8086757660*s_
+    )
+end
+
+---Converts from OKLAB to Linear sRGB
+---@param color Vector3
+---@return Vector3
+function lib.oklabToLinear(color)
+    local l_ = color.x + 0.3963377774 * color.y + 0.2158037573 * color.z;
+    local m_ = color.x - 0.1055613458 * color.y - 0.0638541728 * color.z;
+    local s_ = color.x - 0.0894841775 * color.y - 1.2914855480 * color.z;
+
+    local l = l_*l_*l_;
+    local m = m_*m_*m_;
+    local s = s_*s_*s_;
+
+    return vec(
+         4.0767416621 * l - 3.3077115913 * m + 0.2309699292 * s,
+		-1.2684380046 * l + 2.6097574011 * m - 0.3413193965 * s,
+		-0.0041960863 * l - 0.7034186147 * m + 1.7076147010 * s
+    )
+end
+
+---Converts from LAB to LCh
+---@param color Vector3
+---@return Vector3
+function lib.labToLch(color)
+    return vec(
+        color.x,
+        math.sqrt(color.y * color.y + color.z * color.z),
+        math.deg(math.atan2(color.z, color.y))
+    )
+end
+
+---Converts from LCh to LAB
+---@param color Vector3
+---@return Vector3
+function lib.lchToLab(color)
+    return vec(
+        color.x,
+        color.y * math.cos(math.rad(color.z)),
+        color.y * math.sin(math.rad(color.z))
+    )
+end
+
+
+
+---Converts from sRGB to OKLCh
+---@param color Vector3
+---@return Vector3
+function lib.srgbToOklch(color)
+    return lib.labToLch(lib.linearToOklab(lib.srgbToLinear(color)))
+end
+
+---Converts from OKLCh to sRGB
+---@param color Vector3
+---@return Vector3
+function lib.oklchToSrgb(color)
+    return lib.linearToSrgb(lib.oklabToLinear(lib.lchToLab(color)))
+end
+
+return lib