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authorTor Andersson <tor@ccxvii.net>2025-02-23 18:37:17 +0100
committerTor Andersson <tor@ccxvii.net>2025-03-08 16:32:19 +0100
commitfe2bc3961ec3b3164786074b37e36581b81fa68c (patch)
treebfc80bc4fb161e83f290da6294f0bffe9116500b /tools/colors.js
parenta4c2b8458d1059c373c4a714bce0b5f68a3ce20f (diff)
downloadland-and-freedom-fe2bc3961ec3b3164786074b37e36581b81fa68c.tar.gz
New client and client data processing tools.
Diffstat (limited to 'tools/colors.js')
-rw-r--r--tools/colors.js143
1 files changed, 143 insertions, 0 deletions
diff --git a/tools/colors.js b/tools/colors.js
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+"use strict"
+
+function rgb_from_any(color) {
+ if (typeof color === "string")
+ color = parse_hex(color)
+ switch (color.mode) {
+ case "rgb": return color
+ case "lrgb": return rgb_from_lrgb(color)
+ case "oklab": return rgb_from_oklab(color)
+ }
+}
+
+function lrgb_from_any(color) {
+ switch (color.mode) {
+ case "rgb": return lrgb_from_rgb(color)
+ case "lrgb": return color
+ case "oklab": return lrgb_from_oklab(color)
+ }
+}
+
+function oklab_from_any(color) {
+ switch (color.mode) {
+ case "rgb": return oklab_from_rgb(color)
+ case "lrgb": return oklab_from_lrgb(color)
+ case "oklab": return color
+ }
+}
+
+function format_hex(color) {
+ let { r, g, b } = rgb_from_any(color)
+ let adj = 1
+ r = Math.round(Math.max(0, Math.min(1, r)) * 255)
+ g = Math.round(Math.max(0, Math.min(1, g)) * 255)
+ b = Math.round(Math.max(0, Math.min(1, b)) * 255)
+ let x = (r << 16) | (g << 8) | b
+ return "#" + x.toString(16).padStart(6, "0")
+}
+
+function parse_hex(str) {
+ let x = parseInt(str.substring(1), 16)
+ return {
+ mode: "rgb",
+ r: ((x >> 16) & 255) / 255.0,
+ g: ((x >> 8) & 255) / 255.0,
+ b: ((x) & 255) / 255.0
+ }
+}
+
+function lrgb_from_rgb({ r, g, b }) {
+ function to_linear(c) {
+ let ac = Math.abs(c)
+ if (ac < 0.04045)
+ return c / 12.92
+ return (Math.sign(c) || 1) * Math.pow((ac + 0.055) / 1.055, 2.4)
+ }
+ return {
+ mode: "lrgb",
+ r: to_linear(r),
+ g: to_linear(g),
+ b: to_linear(b)
+ }
+}
+
+function rgb_from_lrgb({ r, g, b }) {
+ function from_linear(c) {
+ let ac = Math.abs(c)
+ if (ac > 0.0031308)
+ return (Math.sign(c) || 1) * (1.055 * Math.pow(ac, 1 / 2.4) - 0.055)
+ return c * 12.92
+ }
+ return {
+ mode: "rgb",
+ r: from_linear(r),
+ g: from_linear(g),
+ b: from_linear(b)
+ }
+}
+
+function oklab_from_lrgb({ r, g, b }) {
+ let L = Math.cbrt(0.4122214708 * r + 0.5363325363 * g + 0.0514459929 * b)
+ let M = Math.cbrt(0.2119034982 * r + 0.6806995451 * g + 0.1073969566 * b)
+ let S = Math.cbrt(0.0883024619 * r + 0.2817188376 * g + 0.6299787005 * b)
+ return {
+ mode: "oklab",
+ l: 0.2104542553 * L + 0.793617785 * M - 0.0040720468 * S,
+ a: 1.9779984951 * L - 2.428592205 * M + 0.4505937099 * S,
+ b: 0.0259040371 * L + 0.7827717662 * M - 0.808675766 * S
+ }
+}
+
+function lrgb_from_oklab({ l, a, b }) {
+ let L = Math.pow(l + 0.3963377774 * a + 0.2158037573 * b, 3)
+ let M = Math.pow(l - 0.1055613458 * a - 0.0638541728 * b, 3)
+ let S = Math.pow(l - 0.0894841775 * a - 1.291485548 * b, 3)
+ return {
+ mode: "lrgb",
+ r: +4.0767416621 * L - 3.3077115913 * M + 0.2309699292 * S,
+ g: -1.2684380046 * L + 2.6097574011 * M - 0.3413193965 * S,
+ b: -0.0041960863 * L - 0.7034186147 * M + 1.707614701 * S
+ }
+}
+
+function oklab_from_rgb(rgb) {
+ return oklab_from_lrgb(lrgb_from_rgb(rgb))
+}
+
+function rgb_from_oklab(oklab) {
+ return rgb_from_lrgb(lrgb_from_oklab(oklab))
+}
+
+function format_hsl(rgb) {
+ let { r, g, b } = rgb_from_any(color)
+ let cmin = Math.min(r, g, b)
+ let cmax = Math.max(r, g, b)
+ let delta = cmax - cmin
+ let h = 0, s = 0, l = 0
+
+ if (delta == 0)
+ h = 0
+ else if (cmax == r)
+ h = ((g - b) / delta) % 6
+ else if (cmax == g)
+ h = (b - r) / delta + 2
+ else
+ h = (r - g) / delta + 4
+
+ h = Math.round(h * 60)
+
+ if (h < 0)
+ h += 360
+
+ l = (cmax + cmin) / 2
+
+ s = delta == 0 ? 0 : delta / (1 - Math.abs(2 * l - 1))
+
+ s = Math.round(s * 100)
+ l = Math.round(l * 100)
+
+ return "hsl(" + h + "," + s + "%," + l + "%)"
+}
+
+if (typeof module === "object")
+ module.exports = { format_hex, parse_hex, rgb_from_any, lrgb_from_any, oklab_from_any, format_hsl }