viridis/types/Gradient.d.ts

Color gradients for data visualization

import { Color } from './Color';
/**
 * Represents a linear, uniform color gradient.
 */
export declare class Gradient {
    readonly colors: Array<Color>;
    /**
     * Define a new linear color gradient using an array of
     * color stops. Gradients can include any number of color
     * stops, which are all equally spaced from one another.
     * @param colors An array of colors to define this color gradient
     * @example
     * ```js
     * const redBlue = new Gradient([
     *     new Color(255, 0, 0),
     *     new Color(0, 0, 255),
     * ]);
     * ```
     */
    constructor(colors: Array<Color>);
    /**
     * Linearly interpolate between color stops to get a color along this gradient.
     * @param x A value between `min, max` to use for selecting a color along this
     * gradient. An `x` value of `min` will select the first color stop, and an `x`
     * value of `max` will select the last color stop. If `min` and `max` are not
     * present, `x` should be a normalized value.
     * @param min The minimum range of the color scale
     * @param max The maximum range of the color scale
     * @returns The interpolated color
     * @example
     * ```js
     * const myColor = redBlue.getColor(0.5);
     * // Returns interpolated color (127.5, 0, 127.5)
     * ```
     */
    getColor(x: number, min?: number, max?: number): Color;
    /**
     * Return a string representation of this gradient.
     * @param deg The direction of this color gradient, in degrees
     * @returns A valid CSS color gradient
     * @example
     * ```js
     * const str = redBlue.toString(180);
     * // linear-gradient(180deg,rgba(255,0,0,100%),rgba(0,0,255,100%))
     * ```
     */
    toString(deg?: number): string;
    /**
     * Generate an SVG linear gradient element.
     * @param id The ID of this linear gradient, to be obtained with `url(#id)`
     * @param deg The angle of this color gradient, in degrees clockwise from the vertical
     * @returns A valid SVG color gradient
     * @example
     * ```js
     * const linearGrad = grad.toSVG('myGrad');
     * // Returns a <linearGradient> element to be appended onto <defs>
     * ```
     */
    toSVG(id: string, deg?: number): SVGLinearGradientElement;
}