in book/master_middleman/source/javascripts/waypoints/waypoint.js [8:40]
function Waypoint(options) {
if (!options) {
throw new Error('No options passed to Waypoint constructor')
}
if (!options.element) {
throw new Error('No element option passed to Waypoint constructor')
}
if (!options.handler) {
throw new Error('No handler option passed to Waypoint constructor')
}
this.key = 'waypoint-' + keyCounter
this.options = Waypoint.Adapter.extend({}, Waypoint.defaults, options)
this.element = this.options.element
this.adapter = new Waypoint.Adapter(this.element)
this.callback = options.handler
this.axis = this.options.horizontal ? 'horizontal' : 'vertical'
this.enabled = this.options.enabled
this.triggerPoint = null
this.group = Waypoint.Group.findOrCreate({
name: this.options.group,
axis: this.axis
})
this.context = Waypoint.Context.findOrCreateByElement(this.options.context)
if (Waypoint.offsetAliases[this.options.offset]) {
this.options.offset = Waypoint.offsetAliases[this.options.offset]
}
this.group.add(this)
this.context.add(this)
allWaypoints[this.key] = this
keyCounter += 1
}