import { bound01, pad2 } from './util';
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// `rgbToHsl`, `rgbToHsv`, `hslToRgb`, `hsvToRgb` modified from:
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// <http://mjijackson.com/2008/02/rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript>
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/**
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* Handle bounds / percentage checking to conform to CSS color spec
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* <http://www.w3.org/TR/css3-color/>
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* *Assumes:* r, g, b in [0, 255] or [0, 1]
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* *Returns:* { r, g, b } in [0, 255]
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*/
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export function rgbToRgb(r, g, b) {
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return {
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r: bound01(r, 255) * 255,
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g: bound01(g, 255) * 255,
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b: bound01(b, 255) * 255,
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};
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}
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/**
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* Converts an RGB color value to HSL.
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* *Assumes:* r, g, and b are contained in [0, 255] or [0, 1]
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* *Returns:* { h, s, l } in [0,1]
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*/
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export function rgbToHsl(r, g, b) {
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r = bound01(r, 255);
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g = bound01(g, 255);
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b = bound01(b, 255);
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var max = Math.max(r, g, b);
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var min = Math.min(r, g, b);
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var h = 0;
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var s = 0;
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var l = (max + min) / 2;
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if (max === min) {
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s = 0;
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h = 0; // achromatic
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}
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else {
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var d = max - min;
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s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
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switch (max) {
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case r:
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h = (g - b) / d + (g < b ? 6 : 0);
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break;
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case g:
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h = (b - r) / d + 2;
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break;
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case b:
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h = (r - g) / d + 4;
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break;
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default:
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break;
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}
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h /= 6;
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}
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return { h: h, s: s, l: l };
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}
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function hue2rgb(p, q, t) {
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if (t < 0) {
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t += 1;
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}
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if (t > 1) {
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t -= 1;
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}
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if (t < 1 / 6) {
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return p + (q - p) * (6 * t);
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}
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if (t < 1 / 2) {
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return q;
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}
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if (t < 2 / 3) {
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return p + (q - p) * (2 / 3 - t) * 6;
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}
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return p;
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}
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/**
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* Converts an HSL color value to RGB.
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*
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* *Assumes:* h is contained in [0, 1] or [0, 360] and s and l are contained [0, 1] or [0, 100]
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* *Returns:* { r, g, b } in the set [0, 255]
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*/
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export function hslToRgb(h, s, l) {
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var r;
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var g;
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var b;
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h = bound01(h, 360);
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s = bound01(s, 100);
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l = bound01(l, 100);
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if (s === 0) {
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// achromatic
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g = l;
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b = l;
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r = l;
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}
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else {
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var q = l < 0.5 ? l * (1 + s) : l + s - l * s;
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var p = 2 * l - q;
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r = hue2rgb(p, q, h + 1 / 3);
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g = hue2rgb(p, q, h);
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b = hue2rgb(p, q, h - 1 / 3);
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}
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return { r: r * 255, g: g * 255, b: b * 255 };
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}
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/**
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* Converts an RGB color value to HSV
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*
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* *Assumes:* r, g, and b are contained in the set [0, 255] or [0, 1]
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* *Returns:* { h, s, v } in [0,1]
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*/
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export function rgbToHsv(r, g, b) {
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r = bound01(r, 255);
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g = bound01(g, 255);
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b = bound01(b, 255);
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var max = Math.max(r, g, b);
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var min = Math.min(r, g, b);
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var h = 0;
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var v = max;
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var d = max - min;
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var s = max === 0 ? 0 : d / max;
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if (max === min) {
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h = 0; // achromatic
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}
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else {
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switch (max) {
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case r:
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h = (g - b) / d + (g < b ? 6 : 0);
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break;
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case g:
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h = (b - r) / d + 2;
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break;
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case b:
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h = (r - g) / d + 4;
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break;
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default:
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break;
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}
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h /= 6;
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}
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return { h: h, s: s, v: v };
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}
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/**
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* Converts an HSV color value to RGB.
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*
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* *Assumes:* h is contained in [0, 1] or [0, 360] and s and v are contained in [0, 1] or [0, 100]
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* *Returns:* { r, g, b } in the set [0, 255]
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*/
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export function hsvToRgb(h, s, v) {
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h = bound01(h, 360) * 6;
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s = bound01(s, 100);
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v = bound01(v, 100);
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var i = Math.floor(h);
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var f = h - i;
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var p = v * (1 - s);
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var q = v * (1 - f * s);
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var t = v * (1 - (1 - f) * s);
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var mod = i % 6;
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var r = [v, q, p, p, t, v][mod];
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var g = [t, v, v, q, p, p][mod];
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var b = [p, p, t, v, v, q][mod];
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return { r: r * 255, g: g * 255, b: b * 255 };
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}
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/**
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* Converts an RGB color to hex
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*
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* Assumes r, g, and b are contained in the set [0, 255]
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* Returns a 3 or 6 character hex
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*/
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export function rgbToHex(r, g, b, allow3Char) {
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var hex = [
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pad2(Math.round(r).toString(16)),
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pad2(Math.round(g).toString(16)),
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pad2(Math.round(b).toString(16)),
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];
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// Return a 3 character hex if possible
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if (allow3Char &&
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hex[0].startsWith(hex[0].charAt(1)) &&
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hex[1].startsWith(hex[1].charAt(1)) &&
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hex[2].startsWith(hex[2].charAt(1))) {
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return hex[0].charAt(0) + hex[1].charAt(0) + hex[2].charAt(0);
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}
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return hex.join('');
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}
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/**
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* Converts an RGBA color plus alpha transparency to hex
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*
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* Assumes r, g, b are contained in the set [0, 255] and
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* a in [0, 1]. Returns a 4 or 8 character rgba hex
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*/
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// eslint-disable-next-line max-params
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export function rgbaToHex(r, g, b, a, allow4Char) {
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var hex = [
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pad2(Math.round(r).toString(16)),
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pad2(Math.round(g).toString(16)),
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pad2(Math.round(b).toString(16)),
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pad2(convertDecimalToHex(a)),
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];
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// Return a 4 character hex if possible
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if (allow4Char &&
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hex[0].startsWith(hex[0].charAt(1)) &&
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hex[1].startsWith(hex[1].charAt(1)) &&
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hex[2].startsWith(hex[2].charAt(1)) &&
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hex[3].startsWith(hex[3].charAt(1))) {
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return hex[0].charAt(0) + hex[1].charAt(0) + hex[2].charAt(0) + hex[3].charAt(0);
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}
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return hex.join('');
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}
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/**
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* Converts an RGBA color to an ARGB Hex8 string
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* Rarely used, but required for "toFilter()"
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*/
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export function rgbaToArgbHex(r, g, b, a) {
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var hex = [
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pad2(convertDecimalToHex(a)),
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pad2(Math.round(r).toString(16)),
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pad2(Math.round(g).toString(16)),
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pad2(Math.round(b).toString(16)),
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];
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return hex.join('');
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}
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/** Converts a decimal to a hex value */
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export function convertDecimalToHex(d) {
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return Math.round(parseFloat(d) * 255).toString(16);
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}
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/** Converts a hex value to a decimal */
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export function convertHexToDecimal(h) {
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return parseIntFromHex(h) / 255;
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}
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/** Parse a base-16 hex value into a base-10 integer */
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export function parseIntFromHex(val) {
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return parseInt(val, 16);
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}
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export function numberInputToObject(color) {
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return {
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r: color >> 16,
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g: (color & 0xff00) >> 8,
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b: color & 0xff,
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};
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}
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