On Feb 5, 2011, at 11:18 PM, Yaron Minsky wrote:

> Sorry for the noise: I think I answered my own question.  You basically stick 
> a pinhole in the image you want to place at its desired center

Yes, the "desired center" is sometimes tricky.  In particular, what one 
probably means by the "center" of an equilateral triangle is NOT the center of 
its bounding rectangle, but is rather 2/3 of the way down.

One thing I've done (without using pinholes, although that's perhaps a more 
intuitive approach) is to overlay a shape at specified (x,y) coordinates onto a 
transparent circle that's big enough to contain it completely.  You can do this 
using overlay/xy, or place-image, or whatever.


Stephen Bloch
[email protected]


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