react-native-zoom-toolkit
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Most complete set of pinch to zoom utilites for React Native
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text/typescript
import type { PanGestureEvent, SwipeDirection, Vector } from '../types';
type SwipeOptions = {
time: number;
boundaries: Vector<number>;
position: Vector<number>;
translate: Vector<number>;
};
const SWIPE_TIME = 175;
const SWIPE_VELOCITY = 500;
const SWIPE_DISTANCE = 20;
export const getSwipeDirection = (
e: PanGestureEvent,
options: SwipeOptions
): SwipeDirection | undefined => {
'worklet';
const { time, boundaries, position, translate } = options;
const deltaTime = performance.now() - time;
const { x: boundX, y: boundY } = boundaries;
const swipedDistanceX = Math.abs(position.x - e.absoluteX) >= SWIPE_DISTANCE;
const swipedDistanceY = Math.abs(position.y - e.absoluteY) >= SWIPE_DISTANCE;
const swipedInTime = deltaTime <= SWIPE_TIME;
const swipeRight =
e.velocityX >= SWIPE_VELOCITY && swipedDistanceX && swipedInTime;
const inRightBound = translate.x === boundX;
if (swipeRight && inRightBound) return 'right';
const swipeLeft =
e.velocityX <= -1 * SWIPE_VELOCITY && swipedDistanceX && swipedInTime;
const inLeftBound = translate.x === -1 * boundX;
if (swipeLeft && inLeftBound) return 'left';
const swipeUp =
e.velocityY <= -1 * SWIPE_VELOCITY && swipedDistanceY && swipedInTime;
const inUpperBound = translate.y === -1 * boundY;
if (swipeUp && inUpperBound) return 'up';
const swipeDown =
e.velocityY >= SWIPE_VELOCITY && swipedDistanceY && swipedInTime;
const inLowerBound = translate.y === boundY;
if (swipeDown && inLowerBound) return 'down';
return undefined;
};