ok, I just took the original app built on .9.0 beta 2, was a solid 55-60 fps in game (run straight from device)
after simple move to 0.99 rc I see a really erratic performance... sometimes it starts with 25-30, then climbs to 45-50 fps. usually starts with the latter value. once I had it between 55-60, but only once and I run the game like 5 times
as I said - no changes to the original app (except for turning off box2d debug view) whatsoever
also - there is some really severe performance penalty for the touch handling. takes away 5-10 fps (I don't use touch dispatcher, just check if the touch in the layer has a collision with a sprite button)
EDIT: I think I found the cuplrit - uncommenting just 2 [CCBitmapFontLabel setString] function calls made it go back to 60 fps. I know that setString is really expensive, but they were on in the original game, so there is still some curious performance problem
also - shouldnt setString on BitmapFontLabel be cheaper ? it is generally not recommended to do it with CCLabels as they need to be released and reconstructed on each call. weren't solutions based on atlases supposed to solve it ?
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other than that had little problems moving to .99, just had to change box2d draw debug and touch handling (from BOOL to void, and no return kEventHandled)