I was looking at SPView processTouchEvent: and noticed that it creates new SPTouch events every time. This is unlike native UITouches, which persist across invocations of touchesBegan:, touchesMoved: etc, allowing one to easily track the motions of individual fingers. As far as I can tell, this information is lost with SPTouches.
Am I correct? If so, is there an easy way to work around this? Maybe this is actually a feature request 
Thanks!
Hi bunnyhero!
You have to differentiate between "SPTouchEvent" and "SPTouch".
"SPTouchEvent" is the event object that informs you that a touch has been encountered on a specific object (that one is not reused).
You then use this object to receive the individual "SPTouch" objects. And those objects are reused. When any finger on the screen moves, a new SPTouchEvent will be dispatched, and all its SPTouches will have updated values. Any SPTouch object goes through the phases "SPTouchPhaseBegan", "SPTouchPhaseMoved", optionally "SPTouchPhaseStationary" and finally "SPTouchPhaseEnded".
I hope this helps!
BTW, thanks a lot for the really nice blog entry you wrote about Sparrow! Great to have you around in the forum =)
Daniel
CastIrony
Member
I was looking through the source of SPView, and it seems like whenever a touch handler is called, it loops over the UITouch objects and makes a new SPTouch instance for each, rather than reusing them as you claim.
Am I reading this wrong? Did this change in the last 11 months?
At the moment, I'm patching this myself by adding a pointer to the UITouch to each SPTouch so I can tell them apart, as bunnyhero suggested.
Hi Castirony,
the code you're looking at is misleading -- in the SPView class, I create new SPTouch objects, you're right with that. But those objects are then forwarded to "SPTouchProcessor", which uses those objects only to check if those are the successors of its set of touch objects, so that it can update those. (See here).
Thus, one touch object should always travel through all of its phases.
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