Method init

src/Observer.js:152–420

(vars)

	}

	init(vars) {
		_coreInitted || _initCore(gsap) || console.warn("Please gsap.registerPlugin(Observer)");
		ScrollTrigger || _setScrollTrigger();
		let {tolerance, dragMinimum, type, target, lineHeight, debounce, preventDefault, onStop, onStopDelay, ignore, wheelSpeed, event, onDragStart, onDragEnd, onDrag, onPress, onRelease, onRight, onLeft, onUp, onDown, onChangeX, onChangeY, onChange, onToggleX, onToggleY, onHover, onHoverEnd, onMove, ignoreCheck, isNormalizer, onGestureStart, onGestureEnd, onWheel, onEnable, onDisable, onClick, scrollSpeed, capture, allowClicks, lockAxis, onLockAxis} = vars;
		this.target = target = _getTarget(target) || _docEl;
		this.vars = vars;
		ignore && (ignore = gsap.utils.toArray(ignore));
		tolerance = tolerance || 1e-9;
		dragMinimum = dragMinimum || 0;
		wheelSpeed = wheelSpeed || 1;
		scrollSpeed = scrollSpeed || 1;
		type = type || "wheel,touch,pointer";
		debounce = debounce !== false;
		lineHeight || (lineHeight = parseFloat(_win.getComputedStyle(_body).lineHeight) || 22); // note: browser may report "normal", so default to 22.
		let id, onStopDelayedCall, dragged, moved, wheeled, locked, axis,
			self = this,
			prevDeltaX = 0,
			prevDeltaY = 0,
			passive = vars.passive || (!preventDefault && vars.passive !== false),
			scrollFuncX = _getScrollFunc(target, _horizontal),
			scrollFuncY = _getScrollFunc(target, _vertical),
			scrollX = scrollFuncX(),
			scrollY = scrollFuncY(),
			limitToTouch = ~type.indexOf("touch") && !~type.indexOf("pointer") && _eventTypes[0] === "pointerdown", // for devices that accommodate mouse events and touch events, we need to distinguish.
			isViewport = _isViewport(target),
			ownerDoc = target.ownerDocument || _doc,
			deltaX = [0, 0, 0], // wheel, scroll, pointer/touch
			deltaY = [0, 0, 0],
			onClickTime = 0,
			clickCapture = () => onClickTime = _getTime(),
			_ignoreCheck = (e, isPointerOrTouch) => (self.event = e) && (ignore && _isWithin(e.target, ignore)) || (isPointerOrTouch && limitToTouch && e.pointerType !== "touch") || (ignoreCheck && ignoreCheck(e, isPointerOrTouch)),
			onStopFunc = () => {
				self._vx.reset();
				self._vy.reset();
				onStopDelayedCall.pause();
				onStop && onStop(self);
			},
			update = () => {
				let dx = self.deltaX = _getAbsoluteMax(deltaX),
					dy = self.deltaY = _getAbsoluteMax(deltaY),
					changedX = Math.abs(dx) >= tolerance,
					changedY = Math.abs(dy) >= tolerance;
				onChange && (changedX || changedY) && onChange(self, dx, dy, deltaX, deltaY); // in ScrollTrigger.normalizeScroll(), we need to know if it was touch/pointer so we need access to the deltaX/deltaY Arrays before we clear them out.
				if (changedX) {
					onRight && self.deltaX > 0 && onRight(self);
					onLeft && self.deltaX < 0 && onLeft(self);
					onChangeX && onChangeX(self);
					onToggleX && ((self.deltaX < 0) !== (prevDeltaX < 0)) && onToggleX(self);
					prevDeltaX = self.deltaX;
					deltaX[0] = deltaX[1] = deltaX[2] = 0
				}
				if (changedY) {
					onDown && self.deltaY > 0 && onDown(self);
					onUp && self.deltaY < 0 && onUp(self);
					onChangeY && onChangeY(self);
					onToggleY && ((self.deltaY < 0) !== (prevDeltaY < 0)) && onToggleY(self);
					prevDeltaY = self.deltaY;
					deltaY[0] = deltaY[1] = deltaY[2] = 0