onTouchMove()

in js/controllers/touch.js [119:208]
71 lines of code
22 McCabe index (conditional complexity)

	onTouchMove( event ) {

		if( this.isSwipePrevented( event.target ) ) return true;

		let config = this.Reveal.getConfig();

		// Each touch should only trigger one action
		if( !this.touchCaptured ) {
			this.Reveal.onUserInput( event );

			let currentX = event.touches[0].clientX;
			let currentY = event.touches[0].clientY;

			// There was only one touch point, look for a swipe
			if( event.touches.length === 1 && this.touchStartCount !== 2 ) {

				let availableRoutes = this.Reveal.availableRoutes({ includeFragments: true });

				let deltaX = currentX - this.touchStartX,
					deltaY = currentY - this.touchStartY;

				if( deltaX > SWIPE_THRESHOLD && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
					this.touchCaptured = true;
					if( config.navigationMode === 'linear' ) {
						if( config.rtl ) {
							this.Reveal.next();
						}
						else {
							this.Reveal.prev();
						}
					}
					else {
						this.Reveal.left();
					}
				}
				else if( deltaX < -SWIPE_THRESHOLD && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
					this.touchCaptured = true;
					if( config.navigationMode === 'linear' ) {
						if( config.rtl ) {
							this.Reveal.prev();
						}
						else {
							this.Reveal.next();
						}
					}
					else {
						this.Reveal.right();
					}
				}
				else if( deltaY > SWIPE_THRESHOLD && availableRoutes.up ) {
					this.touchCaptured = true;
					if( config.navigationMode === 'linear' ) {
						this.Reveal.prev();
					}
					else {
						this.Reveal.up();
					}
				}
				else if( deltaY < -SWIPE_THRESHOLD && availableRoutes.down ) {
					this.touchCaptured = true;
					if( config.navigationMode === 'linear' ) {
						this.Reveal.next();
					}
					else {
						this.Reveal.down();
					}
				}

				// If we're embedded, only block touch events if they have
				// triggered an action
				if( config.embedded ) {
					if( this.touchCaptured || this.Reveal.isVerticalSlide() ) {
						event.preventDefault();
					}
				}
				// Not embedded? Block them all to avoid needless tossing
				// around of the viewport in iOS
				else {
					event.preventDefault();
				}

			}
		}
		// There's a bug with swiping on some Android devices unless
		// the default action is always prevented
		else if( isAndroid ) {
			event.preventDefault();
		}

	}