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allc

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A small typescript package for color conversion.

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/** * Helper function for converting HSL to RGB. * * @param h The hue component of HSL, in radians. * @param s The saturation component of HSL, typically in the range [0, 1]. * @param l The lightness component of HSL, typically in the range [0, 1]. * @param n A component-specific number. * * @returns The RGB component, typically in the range [0, 1]. * @see https://en.wikipedia.org/wiki/HSL_and_HSV#HSL_to_RGB_alternative */ const f = (h, s, l, n) => { const k = (n + h * 6 / Math.PI) % 12; return l - s * Math.min(l, 1 - l) * Math.max(-1, Math.min(k - 3, 9 - k, 1)); }; /** * Calculates the red component of RGB from HSL. * * @param h The hue component of HSL, in radians. * @param s The saturation component of HSL, typically in the range [0, 1]. * @param l The lightness component of HSL, typically in the range [0, 1]. * * @returns The red component, typically in the range [0, 1]. * @see https://en.wikipedia.org/wiki/HSL_and_HSV#HSL_to_RGB_alternative */ export const toRGBRFromHSL = (h, s, l) => f(h, s, l, 0); /** * Calculates the green component of RGB from HSL. * * @param h The hue component of HSL, in radians. * @param s The saturation component of HSL, typically in the range [0, 1]. * @param l The lightness component of HSL, typically in the range [0, 1]. * * @returns The green component, typically in the range [0, 1]. * @see https://en.wikipedia.org/wiki/HSL_and_HSV#HSL_to_RGB_alternative */ export const toRGBGFromHSL = (h, s, l) => f(h, s, l, 8); /** * Calculates the blue component of RGB from HSL. * * @param h The hue component of HSL, in radians. * @param s The saturation component of HSL, typically in the range [0, 1]. * @param l The lightness component of HSL, typically in the range [0, 1]. * * @returns The blue component, typically in the range [0, 1]. * @see https://en.wikipedia.org/wiki/HSL_and_HSV#HSL_to_RGB_alternative */ export const toRGBBFromHSL = (h, s, l) => f(h, s, l, 4);