Tldraw/packages/core/src/hooks/useZoomEvents.ts

117 wiersze
3.8 KiB
TypeScript

/* eslint-disable @typescript-eslint/ban-ts-comment */
/* eslint-disable @typescript-eslint/explicit-module-boundary-types */
import * as React from 'react'
import { useTLContext } from './useTLContext'
import { Handler, useGesture, WebKitGestureEvent } from '@use-gesture/react'
import { Vec } from '@tldraw/vec'
// Capture zoom gestures (pinches, wheels and pans)
export function useZoomEvents<T extends HTMLElement>(zoom: number, ref: React.RefObject<T>) {
const rOriginPoint = React.useRef<number[] | undefined>(undefined)
const rPinchPoint = React.useRef<number[] | undefined>(undefined)
const rDelta = React.useRef<number[]>([0, 0])
const { inputs, bounds, callbacks } = useTLContext()
React.useEffect(() => {
const preventGesture = (event: TouchEvent) => event.preventDefault()
// @ts-ignore
document.addEventListener('gesturestart', preventGesture)
// @ts-ignore
document.addEventListener('gesturechange', preventGesture)
return () => {
// @ts-ignore
document.removeEventListener('gesturestart', preventGesture)
// @ts-ignore
document.removeEventListener('gesturechange', preventGesture)
}
}, [])
const handleWheel = React.useCallback<Handler<'wheel', WheelEvent>>(
({ delta, event: e }) => {
e.preventDefault()
if (e.altKey && e.buttons === 0) {
const point = inputs.pointer?.point ?? [bounds.width / 2, bounds.height / 2]
const info = inputs.pinch(point, point)
callbacks.onZoom?.({ ...info, delta: [...point, -e.deltaY] }, e)
return
}
if (inputs.isPinching) return
if (Vec.isEqual(delta, [0, 0])) return
const info = inputs.pan(delta, e as WheelEvent)
callbacks.onPan?.(info, e)
},
[callbacks, inputs, bounds]
)
const handlePinchStart = React.useCallback<
Handler<'pinch', WheelEvent | PointerEvent | TouchEvent | WebKitGestureEvent>
>(
({ origin, event }) => {
const elm = ref.current
if (!elm || !(event.target === elm || elm.contains(event.target as Node))) return
const info = inputs.pinch(origin, origin)
inputs.isPinching = true
callbacks.onPinchStart?.(info, event)
rPinchPoint.current = info.point
rOriginPoint.current = info.origin
rDelta.current = [0, 0]
},
[callbacks, inputs, bounds]
)
const handlePinch = React.useCallback<
Handler<'pinch', WheelEvent | PointerEvent | TouchEvent | WebKitGestureEvent>
>(
({ origin, event, offset }) => {
const elm = ref.current
if (!(event.target === elm || elm?.contains(event.target as Node))) return
if (!rOriginPoint.current) return
const info = inputs.pinch(origin, rOriginPoint.current)
const trueDelta = Vec.sub(info.delta, rDelta.current)
rDelta.current = info.delta
callbacks.onPinch?.(
{
...info,
point: info.point,
origin: rOriginPoint.current,
delta: [...trueDelta, offset[0]],
},
event
)
rPinchPoint.current = origin
},
[callbacks, inputs, bounds]
)
const handlePinchEnd = React.useCallback<
Handler<'pinch', WheelEvent | PointerEvent | TouchEvent | WebKitGestureEvent>
>(({ origin, event }) => {
const elm = ref.current
if (!(event.target === elm || elm?.contains(event.target as Node))) return
const info = inputs.pinch(origin, origin)
inputs.isPinching = false
callbacks.onPinchEnd?.(info, event)
rPinchPoint.current = undefined
rOriginPoint.current = undefined
rDelta.current = [0, 0]
}, [])
useGesture(
{
onWheel: handleWheel,
onPinchStart: handlePinchStart,
onPinch: handlePinch,
onPinchEnd: handlePinchEnd,
},
{
target: ref,
eventOptions: { passive: false },
pinch: {
from: zoom,
scaleBounds: () => ({ from: inputs.zoom, max: 5, min: 0.1 }),
},
}
)
}