pixel-editor/js/Color.js

168 lines
5.1 KiB
JavaScript
Raw Normal View History

// OPTIMIZABLE: add a normalize function that returns the normalized colour in the current
// format.
class Color {
constructor(fmt, v1, v2, v3, v4) {
this.fmt = fmt;
switch (fmt) {
case 'hsv':
this.hsv = {h: v1, s: v2, v: v3};
this.rgb = Color.hsvToRgb(this.hsv);
this.hsl = Color.rgbToHsl(this.rgb);
this.hex = Color.rgbToHex(this.rgb);
break;
case 'hsl':
this.hsl = {h: v1, s: v2, l: v3};
this.rgb = Color.hslToRgb(this.hsl);
this.hsv = Color.rgbToHsv(this.rgb);
this.hex = Color.rgbToHex(this.rgb);
break;
case 'rgb':
this.rgb = {r: v1, g: v2, b: v3};
this.hsl = Color.rgbToHsl(this.rgb);
this.hsv = Color.rgbToHsv(this.rgb);
this.hex = Color.rgbToHex(this.rgb);
break;
case 'hex':
this.hex = v1;
this.rgb = Color.hexToRgb(this.hex);
this.hsl = Color.rgbToHsl(this.rgb);
this.hsv = Color.rgbToHsv(this.rgb);
break;
default:
console.error("Unsupported color mode " + fmt);
break;
}
}
static hexToRgb(hex, divisor) {
//if divisor isn't set, set it to one (so it has no effect)
divisor = divisor || 1;
//split given hex code into array of 3 values
2021-07-11 18:32:49 +03:00
const result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex.trim());
return result ? {
r: parseInt(result[1], 16)/divisor,
g: parseInt(result[2], 16)/divisor,
b: parseInt(result[3], 16)/divisor
} : null;
}
static rgbToHex(rgb) {
2021-07-12 00:27:48 +03:00
function componentToHex (c) {
var hex = Math.round(c).toString(16);
return hex.length == 1 ? "0" + hex : hex.substring(0, 2);
}
return componentToHex(rgb.r) + componentToHex(rgb.g) + componentToHex(rgb.b);
}
static hslToRgb(hsl) {
2021-07-11 18:32:49 +03:00
let r, g, b;
let h = hsl.h, s = hsl.s, l = hsl.l;
2021-07-12 00:27:48 +03:00
h /= 360;
s /= 100;
l /= 100;
if(s == 0){
r = g = b = l; // achromatic
}else{
2021-07-11 18:32:49 +03:00
const hue2rgb = function hue2rgb(p, q, t){
if(t < 0) t += 1;
if(t > 1) t -= 1;
if(t < 1/6) return p + (q - p) * 6 * t;
if(t < 1/2) return q;
if(t < 2/3) return p + (q - p) * (2/3 - t) * 6;
return p;
}
2021-07-11 18:32:49 +03:00
const q = l < 0.5 ? l * (1 + s) : l + s - l * s;
const p = 2 * l - q;
r = hue2rgb(p, q, h + 1/3);
g = hue2rgb(p, q, h);
b = hue2rgb(p, q, h - 1/3);
}
return {
r:Math.round(r * 255),
g:Math.round(g * 255),
b:Math.round(b * 255)
};
}
static rgbToHsl(rgb) {
2021-07-11 18:32:49 +03:00
let r, g, b;
r = rgb.r; g = rgb.g; b = rgb.b;
r /= 255, g /= 255, b /= 255;
2021-07-11 18:32:49 +03:00
const max = Math.max(r, g, b), min = Math.min(r, g, b);
let hue, saturation, luminosity = (max + min) / 2;
if(max == min){
hue = saturation = 0; // achromatic
}else{
2021-07-11 18:32:49 +03:00
const d = max - min;
saturation = luminosity > 0.5 ? d / (2 - max - min) : d / (max + min);
switch(max){
case r: hue = (g - b) / d + (g < b ? 6 : 0); break;
case g: hue = (b - r) / d + 2; break;
case b: hue = (r - g) / d + 4; break;
}
hue /= 6;
}
2021-07-12 00:27:48 +03:00
return {h:hue*360, s:saturation*100, l:luminosity*100};
}
static hsvToRgb(hsv) {
2021-07-11 18:32:49 +03:00
let r, g, b, h, s, v;
h = hsv.h; s = hsv.s; v = hsv.v;
h /= 360;
s /= 100;
v /= 100;
2021-07-11 18:32:49 +03:00
const i = Math.floor(h * 6);
const f = h * 6 - i;
const p = v * (1 - s);
const q = v * (1 - f * s);
const t = v * (1 - (1 - f) * s);
switch (i % 6) {
case 0: r = v, g = t, b = p; break;
case 1: r = q, g = v, b = p; break;
case 2: r = p, g = v, b = t; break;
case 3: r = p, g = q, b = v; break;
case 4: r = t, g = p, b = v; break;
case 5: r = v, g = p, b = q; break;
}
return {r: r * 255, g: g * 255, b: b * 255 };
}
static rgbToHsv(rgb) {
let r = rgb.r, g = rgb.g, b = rgb.b;
r /= 255, g /= 255, b /= 255;
let max = Math.max(r, g, b), min = Math.min(r, g, b);
let myH, myS, myV = max;
let d = max - min;
myS = max == 0 ? 0 : d / max;
if (max == min) {
myH = 0; // achromatic
}
else {
switch (max) {
case r: myH = (g - b) / d + (g < b ? 6 : 0); break;
case g: myH = (b - r) / d + 2; break;
case b: myH = (r - g) / d + 4; break;
}
myH /= 6;
}
return {h: myH * 360, s: myS * 100, v: myV * 100};
}
}