Trouble with graphics display in OS X

[James Hurley]

I have been having a great deal of trouble switching over to OS X.

The following handler illustrates my problem:

on mouseUP
   set the loc of grc "ball" to 100, 100
   put .1 into dx
   put .1 into dy
   put the loc of grc "ball" into tBallLoc
   repeat 5000
     add dx to item 1 of tBallLoc
     add dy to item 2 of tBallLoc
     set the loc of grc "ball" to tBallLoc
     --wait 1 millisec
   end repeat
   set the loc of grc "ball" to 100,100
end mouseUP

In OS 9, this causes the ball graphic to  slide smoothly along a 45 
degree line. In OS X the ball moves erratically to two or three spots 
on the line and then quickly back to the starting location.

(Since the loc consists only of integers, this should move the ball 
smoothly through points 100,100 to 101,101 to 102,102 ... 600,600.)

If I insert the "wait 1 millisec" the motion is smooth, but slow. It 
takes, of course, 5 seconds plus.

Is this a known problem in OS X?

I am running RR 2.2.1 and OS X 2.3 on a PowerBook G4

Jim