27 lines
543 B
TypeScript
27 lines
543 B
TypeScript
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// Copyright 2024 Signal Messenger, LLC
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// SPDX-License-Identifier: AGPL-3.0-only
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// https://en.wikipedia.org/wiki/HSL_and_HSV#HSL_to_RGB_alternative
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export function hslToRGB(
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h: number,
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s: number,
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l: number
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): {
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r: number;
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g: number;
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b: number;
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} {
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const a = s * Math.min(l, 1 - l);
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function f(n: number): number {
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const k = (n + h / 30) % 12;
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return l - a * Math.max(Math.min(k - 3, 9 - k, 1), -1);
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}
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return {
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r: Math.round(255 * f(0)),
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g: Math.round(255 * f(8)),
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b: Math.round(255 * f(4)),
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};
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}
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