react-native-reanimated/src/platformFunctions/getRelativeCoords.ts

More powerful alternative to Animated library for React Native.

'use strict';
import type { Component } from 'react';

import type { AnimatedRef } from '../hook/commonTypes';
import { measure } from './measure';

/** An object which contains relative coordinates. */
export interface ComponentCoords {
  x: number;
  y: number;
}

/**
 * Lets you determines the location on the screen, relative to the given view.
 *
 * @param animatedRef - An [animated
 *   ref](https://docs.swmansion.com/react-native-reanimated/docs/core/useAnimatedRef#returns)
 *   connected to the component you'd want to get the coordinates from.
 * @param absoluteX - A number which is an absolute x coordinate.
 * @param absoluteY - A number which is an absolute y coordinate.
 * @returns An object which contains relative coordinates -
 *   {@link ComponentCoords}.
 * @see https://docs.swmansion.com/react-native-reanimated/docs/utilities/getRelativeCoords
 */
export function getRelativeCoords(
  animatedRef: AnimatedRef<Component>,
  absoluteX: number,
  absoluteY: number
): ComponentCoords | null {
  'worklet';
  const parentCoords = measure(animatedRef);
  if (parentCoords === null) {
    return null;
  }
  return {
    x: absoluteX - parentCoords.pageX,
    y: absoluteY - parentCoords.pageY,
  };
}