Canvas event.pointerId : returns very (too) big number in iOs

on iPad (iOS 15.7 / Safari) : event.pointerId returns value in the range -1525662976.
(each new pointer decrement this value)

I can see this value on the iPad screen (monitoring canvas value) , but it's probably too big for OSC, so it's truncated (seems to never change, stuck to -1525662976.)

When using (iOS 15.7 / Chrome) : It's not a negative number, but it's still very large: 662156864
(each new pointer increment this value)

on windows / multitouch screen : works as expected.
pointerId always start from 0 (= first finger on the screen)
and increment for each new touch point.

canvas multitouch TUIO style.json (3.3 KB)

a (hopefully temporary :wink: workaround : add a modulo to event.pointer to keep it in a 'reasonable' range :

event.pointerId%100

That's just another oddity in iOS, although it's actually not an issue as long as the id does what it's supposed to do (identify the touch point).