39 wiersze
992 B
TypeScript
39 wiersze
992 B
TypeScript
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import { Random } from "./random";
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import { range } from "./util";
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/**
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* Clamp the given number to be between 0 and 255, then
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* convert it to hexadecimal.
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*/
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export function clampedByteToHex(value: number): string {
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if (value < 0) {
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value = 0;
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} else if (value > 255) {
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value = 255;
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}
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let hex = value.toString(16);
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if (hex.length === 1) {
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hex = "0" + hex;
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}
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return hex;
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}
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function createRandomColor(rng: Random): string {
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const rgb = range(3).map(() => rng.inRange({ min: 0, max: 255, step: 1 }));
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return "#" + rgb.map(clampedByteToHex).join("");
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}
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/**
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* Create a random color palette with the given number of
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* entries, optionally using the given random number generator.
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*
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* The return value is an Array of strings, where each string is
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* a color hex hash (e.g. `#ff0000`).
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*/
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export function createRandomColorPalette(
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numEntries: number,
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rng: Random = new Random()
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): string[] {
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return range(numEntries).map(() => createRandomColor(rng));
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}
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