The perception of surface orientation from multiple sources of optical information
The first piece of work in did in the “Todd Lab” at OSU.
I had just come off five years at Pixar and a year back in grad school in the Architecture and Planning department. I wrote most of the code for this for making and displaying objects, the interactive ‘gauge figure’ and the like. Farley and Jim came up with the distortion method (these are notoriously Farley’s “potatoes” as compared to my “glavens”. Potato, potato), and Farley and I implemented it. I wrote the gauge figure stuff during a visit with Jan Koenderink, whose book Alvy Ray Smith recommended I look at while back @ Pixar. Crazy.
Abstract: An orientation matching task was used to evaluate observers’ sensitivity to local surface orienta- tion at designated probe points on randomly shaped 3-D objects that were optically defined by tex- ture, lambertian shading, or specular highlights, These surfaces could be stationary or in motion, and they could be viewed either monocularly or stereoscopically, in all possible combinations. It was found that the deformations of shading and/or highlights (either over time or between the two eyes’ views) produced levels of performance similar to those obtained for the optical deformations of tex- tured surfaces. These findings suggest that the human visual system utilizes a much richer array of optical information to support its perception of shape than is typically appreciated.
J. F. Norman, J. T. Todd, and F. Phillips, “The perception of surface orientation from multiple sources of optical information,” Percept Psychophys, vol. 57, no. 5, pp. 629–636, Jul. 1995.