Path: utzoo!attcan!uunet!jarthur!usc!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!mailrus!ncar!umigw!umbio.miami.edu!jherr
From: jherr@umbio.miami.edu (Jack Herrington)
Newsgroups: comp.sys.mac.programmer
Subject: Re: The old "dragging a pict" problem...
Summary: Use an origin of 0,0 before drawing all objects
Keywords: Origin, Pattern offset
Message-ID: <1990Mar16.155028.10860@umigw.miami.edu>
Date: 16 Mar 90 15:50:28 GMT
References: <5168.25f674b1@mva.cs.liv.ac.uk>
Sender: jherr%umbio@umigw.miami.edu
Organization: University of Miami Medical School, Department of Biomedical Computing
Lines: 17

In article <5168.25f674b1@mva.cs.liv.ac.uk> phil@mva.cs.liv.ac.uk writes:
>         The system I'm using at the moment is to draw the picture once into
>an offscreen bitmap, and then to blat it on at the correct location as themouse
>moves around, while simultaneously redrawing the stuff that was underneath, and
>copying new stuff out of the way.  My problem is that using this method, the
>pattern gets out of sync.

When you draw the original image onto the screen, reset the origin to the
upper left hand corner of all of the objects you draw (watch out though, 
clipping will change, etc.)  Then wherever you draw your image the pattern
will always remain the same.

-Jack
--
"Slip kid, slip kid, second generation, I'm a soldier at sixty-three, no
 easy way to be free... No easy way to be free!!!!"
								-The WHO