@visactor/vtable-gantt
Version:
canvas table width high performance
29 lines • 1.38 kB
JavaScript
export class Inertia {
constructor() {}
setScrollHandle(scrollHandle) {
this.scrollHandle = scrollHandle;
}
startInertia(speedX, speedY, friction) {
this.stopped = !1, this.lastTime = Date.now(), this.speedX = speedX, this.speedY = speedY,
this.friction = friction, this.runingId || (this.runingId = requestAnimationFrame(this.inertia.bind(this)));
}
inertia() {
var _a;
if (this.stopped) return;
const now = Date.now(), dffTime = now - this.lastTime;
let stopped = !0;
const f = Math.pow(this.friction, dffTime / 16), newSpeedX = f * this.speedX, newSpeedY = f * this.speedY;
let dx = 0, dy = 0;
Math.abs(newSpeedX) > .05 && (stopped = !1, dx = (this.speedX + newSpeedX) / 2 * dffTime),
Math.abs(newSpeedY) > .05 && (stopped = !1, dy = (this.speedY + newSpeedY) / 2 * dffTime),
null === (_a = this.scrollHandle) || void 0 === _a || _a.call(this, dx, dy), stopped ? this.runingId = null : (this.lastTime = now,
this.speedX = newSpeedX, this.speedY = newSpeedY, this.runingId = requestAnimationFrame(this.inertia.bind(this)));
}
endInertia() {
cancelAnimationFrame(this.runingId), this.runingId = null, this.stopped = !0;
}
isInertiaScrolling() {
return !!this.runingId;
}
}
//# sourceMappingURL=inertia.js.map