Why is “event.offsetX” undefined when “touchstart” event?

Question

I'm trying to capture the position of the touchstart relative to an element (".canvas") Is there any possibility to capture this event offsetX and offsetY ?

$(".canvas").on("mousemove", function(event){
     console.log(event.offsetX + " - " + event.offsetY);
})

With click event: http://jsfiddle.net/jfejc6zw/1/

With touchstart event (Test it with your mobile or simulator) http://jsfiddle.net/jfejc6zw/2/

Thanks in advance!

Answer 1

If you're already using jQuery, why would you bother with the low level event coordinates? Just use the jQuery .offset() and .position() functions, in the knowledge that jQuery already did all the browser-inconsistency solving.