Drawing a "Centered" Circle

[Rob Cozens]

Hi All,

Has anyone given any thought or scripting time to exploring what it 
would take to draw a circle that is centered over the loc of the 
original mouseDown?

In the course of public presentation I would like to project a map 
and allow people in the audience to identify an area on the map by 
drawing a circle around it with a mouse.

Using Transcript's oval tool the loc & shape of a circle change as 
the mouseLoc changes.  I want the effect of a perfect circle growing 
or shrinking around a fixed point as the mouse recedes from or 
approaches that point.

At the moment, the approach I'm contemplating involves:

1.  Drawing a minimal circle on mouseDown
2.  Changing the oval tool's ink (or visible property?) to make a new 
invisible oval.
3.  On mouseMove change the width & height of the original circle to 
the distance between the mouseDown loc and the current mouse loc
4.  On mouseUp delete the invisible oval.

Anyone have any comments or a better solution to offer?

TIA.
-- 

Rob Cozens
CCW, Serendipity Software Company

"And I, which was two fooles, do so grow three;
Who are a little wise, the best fooles bee."

from "The Triple Foole" by John Donne (1572-1631)