Fun with environment maps

December 5, 2002 | My Projects | By: Mark VandeWettering

escher.jpg

I’ve been goofing around a bit with trying to acquire environment maps from real environments for
use in computer graphics. The usual method (quite old, but recently made more popular by
Paul Debevec) is to photograph a reflecting sphere in
the environment of interest. You can see this happening all the time in the extra footage for
Attack of the Clones Toward this end, I wrote a program that unwraps these
spherical images. It took a couple of hours, but it appears to work.

My most fun example so far is to try to do this with M. C. Escher’s drawing of himself
reflected in a sphere.
The first image on the right is a cropped version of his original composition. The image itself isn’t
quite spherical, which could be the result of the a poorly scaled scan. Nevertheless, it isn’t far off,
so I fed it to my program and….

escher.env.jpg
The texture map on the right was the result. It’s a pretty close approximation to correct perspective
in each view, which illustrates Escher’s genius in designing this particular work of art.

Anyway, i thought it was cool.