Adventures in Rotation

Jim Hurley jhurley at infostations.com
Sun Dec 4 21:07:33 EST 2005


>Message: 7
>Date: Sun, 4 Dec 2005 19:16:29 -0500
>From: "Bill Marriott" <wjm at wjm.org>
>Subject: Adventures in Rotation
>To: use-revolution at lists.runrev.com
>Message-ID: <dn00sr$sch$1 at sea.gmane.org>
>
>#13) General flakiness. I would definitely say revCrumplePoly is a better
>name for the revRotatePoly command. Is there any situation where
>revRotatePoly could be useful? Not if it does this. Totally bugged. (I
>suspect the reason why is that Rev doesn't have fractional coordinates?
>Could such a limitation really result in such dramatic distortion? If this
>is the case, then Rev should store fractionals, but render to integers.)


Here, here. I have been promoting fractional coordinates for graphic 
points for some time. Try the following handler:

on mouseUp
   set the loc of me to 200.6,200.4
   put the loc of me into msg box--reveals 200,200

   set the points of grc 1 to 100,100 & cr & 200.4,200.6
   --There is no evidence of the line graphic
   -- The fractional point is not truncated but interpreted as a blank line.
end mouseUp

RR will accept fractional coordinates for controls (it truncates the 
coordinates) but it will not accept fractional graphic points.

You don't get an error message and no feedback that the problem lines 
in the fractional coordinates.

Problems arises when the graphic points are computed; the programmer 
may  not realize that the points are fractional or that RR will not 
accept  fractional points. Any point with a fractional coordinate is 
interpreted as an empty point and therefore a discontinuity.

It has been a while and I forget the details, but I think there was 
support for this change in RR; so far no implementation.

Jim




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