material-motion/dist/getVelocity$.d.ts

Makes it easy to add rich, interactive motion to your application.

import { ObservableWithMotionOperators, Point2D } from './types';
export declare const MAXIMUM_AGE = 250;
export declare const MAXIMUM_INCOMING_DISPATCHES = 5;
export declare type GetVelocity$Args<U extends number | Point2D> = {
    value$: ObservableWithMotionOperators<U>;
    pulse$: ObservableWithMotionOperators<any>;
    maximumVelocity?: number;
    defaultVelocity?: number;
};
/**
 * Computes the velocity of an incoming stream and emits the result. Velocity's
 * denominator is in milliseconds; if the incoming stream is measured in pixels,
 * the resulting stream will be in pixels / millisecond.
 *
 * Velocity is computed by watching the trailing 250ms of up to 5 emissions and
 * measuring the distance between the longest pair of events moving in the
 * current direction.  This approach is more resiliant to anomolous data than a
 * simple (nextPosition - prevPosition) / (nextTime - prevTime).
 *
 * If `pulse$` is supplied, `velocity(pulse$)` will only emit values when
 * `pulse$` emits a value.  This is useful for ensuring that velocity is only
 * calculated when it will be used.
 */
export declare function getVelocity$<U extends number | Point2D>({value$, pulse$, maximumVelocity, defaultVelocity}: GetVelocity$Args<U>): ObservableWithMotionOperators<U>;