Magnifier Reference

[Graham Samuel]

I know this has been done before, but I don't know where to look for the example, so I'm asking here. The idea is that the mouse turns into a magnifying glass over a bitmap image, so that under a circular area centred at the mouseLoc, one sees an enlarged version of the part of the image 'beneath' the glass. I already have two versions of my image - the one the user sees, which is reduced in scale, and the larger-scale original, which is hidden from the user - so I have the material to 'feed' to the magnifier, but I would really like to avoid reinventing the necessary code.

TIA

Graham