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color.ts
根目录 / js / utils / color.ts
1 /**
2 * Converts various color input formats to an {r:0,g:0,b:0} object.
3 *
4 * @param {string} color The string representation of a color
5 * @example
6 * colorToRgb('#000');
7 * @example
8 * colorToRgb('#000000');
9 * @example
10 * colorToRgb('rgb(0,0,0)');
11 * @example
12 * colorToRgb('rgba(0,0,0)');
13 *
14 * @return {{r: number, g: number, b: number, [a]: number}|null}
15 */
16 export const colorToRgb = (color: string) => {
17 let hex3 = color.match(/^#([0-9a-f]{3})$/i);
18 if (hex3 && hex3[1]) {
19 const hex3Value = hex3[1];
20 return {
21 r: parseInt(hex3Value.charAt(0), 16) * 0x11,
22 g: parseInt(hex3Value.charAt(1), 16) * 0x11,
23 b: parseInt(hex3Value.charAt(2), 16) * 0x11,
24 };
25 }
26
27 let hex6 = color.match(/^#([0-9a-f]{6})$/i);
28 if (hex6 && hex6[1]) {
29 const hex6Value = hex6[1];
30 return {
31 r: parseInt(hex6Value.slice(0, 2), 16),
32 g: parseInt(hex6Value.slice(2, 4), 16),
33 b: parseInt(hex6Value.slice(4, 6), 16),
34 };
35 }
36
37 let rgb = color.match(/^rgb\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*\)$/i);
38 if (rgb) {
39 return {
40 r: parseInt(rgb[1], 10),
41 g: parseInt(rgb[2], 10),
42 b: parseInt(rgb[3], 10),
43 };
44 }
45
46 let rgba = color.match(
47 /^rgba\s*\(\s*(\d+)\s*,\s*(\d+)\s*,\s*(\d+)\s*,\s*([\d]+|[\d]*.[\d]+)\s*\)$/i
48 );
49 if (rgba) {
50 return {
51 r: parseInt(rgba[1], 10),
52 g: parseInt(rgba[2], 10),
53 b: parseInt(rgba[3], 10),
54 a: parseFloat(rgba[4]),
55 };
56 }
57
58 return null;
59 };
60
61 /**
62 * Calculates brightness on a scale of 0-255.
63 *
64 * @param {string} color See colorToRgb for supported formats.
65 * @see {@link colorToRgb}
66 */
67 export const colorBrightness = (color: string | { r: number; g: number; b: number } | null) => {
68 if (typeof color === 'string') color = colorToRgb(color);
69
70 if (color) {
71 return (color.r * 299 + color.g * 587 + color.b * 114) / 1000;
72 }
73
74 return null;
75 };
76
76 lines TYPESCRIPT