Framer - Scroll trigger

scrollTrigger.js

# Scroll Trigger
scrollTrigger = (layer, source, start, overFunc, underFunc) ->

	# Setup
	layer.globalY = layer.convertPointToScreen().y
	layer.offsetStart = (layer.globalY+source.contentInset.top)-start

	# Checker
	triggerChecker = () ->
		
		# Process layers
		if source.scrollY < layer.offsetStart
			if layer.triggerState != "off"
				layer.triggerState = "off"
				if underFunc != undefined
					underFunc(layer)
		else if source.scrollY >= layer.offsetStart
			if layer.triggerState != "on"
				layer.triggerState = "on"
				if overFunc != undefined
					overFunc(layer)
	
	# Initialise
	triggerChecker()
	
	# Create Events
	source.onMove ->
		triggerChecker()