/**
 * The golden ratio.
 * @see {@link https://en.wikipedia.org/wiki/Golden_ratio}
 */
export declare const GOLDEN_RATIO = 1.618033988749;
/**
 * Constrains a color component value to single-byte range (`0`-`255`).
 * @param c - A color component value.
 * @returns The input value constrained into single-byte range.
 */
export declare const safeRGBComponent: (c: number) => number;
/**
 * Constructs a 32bit integer value that represents an RGBA color value.
 * @param r - The R component.
 * @param g - The G component.
 * @param b - The B component.
 * @param a - The A component.
 * @returns The constructed color value.
 */
export declare const fromRGBA: (r: number, g: number, b: number, a: number) => number;
/**
 * Constructs a 32bit integer value that represents an RGBA color value.
 * The A component is fixed to `255`
 * @param r - The R component.
 * @param g - The G component.
 * @param b - The B component.
 * @returns The constructed color value.
 */
export declare const fromRGB: (r: number, g: number, b: number) => number;
/**
 * Extracts the R component from a color value.
 * @param color - The color value.
 * @returns The R component of the color value.
 */
export declare const getR: (color: number) => number;
/**
 * Extracts the G component from a color value.
 * @param color - The color value.
 * @returns The G component of the color value.
 */
export declare const getG: (color: number) => number;
/**
 * Extracts the B component from a color value.
 * @param color - The color value.
 * @returns The B component of the color value.
 */
export declare const getB: (color: number) => number;
/**
 * Extracts the A component from a color value.
 * @param color - The color value.
 * @returns The A component of the color value.
 */
export declare const getA: (color: number) => number;
/**
 * Returns a new color that is a blend between a source and a destination
 * color linerally. The alpha component in these colors is ignored. Instead, the provided
 * `alpha` value is used to blend between the two colors.
 * @param src - The source color.
 * @param dst - The destination color.
 * @param alpha - The alpha value to use for blending.
 * @returns The blended color.
 */
export declare const blend: (src: number, dst: number, alpha: number) => number;
/**
 * Returns a new color that is a blend between a source and a destination
 * color additively. The alpha component in these colors is ignored. Instead, the provided
 * `alpha` value is used to blend between the two colors.
 * @param src - The source color.
 * @param dst - The destination color.
 * @param alpha - The alpha value to use for blending.
 * @returns The blended color.
 */
export declare const blendAdditive: (src: number, dst: number, alpha: number) => number;
/**
 * Returns a new color that is a blend between a source and a destination
 * color subtractively. The alpha component in these colors is ignored. Instead, the provided
 * `alpha` value is used to blend between the two colors.
 * @param src - The source color.
 * @param dst - The destination color.
 * @param alpha - The alpha value to use for blending.
 * @returns The blended color.
 */
export declare const blendSubtractive: (src: number, dst: number, alpha: number) => number;
/**
 * Converts a color value to grayscale.
 * @param color - The color to convert.
 * @returns The grayscale value appropriate for the color.
 */
export declare const toGrayScale: (color: number) => number;