I just got word of the Anish Kapoor exhibit going on at the Royal Academy of Arts in London.

It looks like a really fantastic exhibit, but what really caught my eye was Kapoor’s monumental sculpture Tall Tree and the Eye.


I just couldn’t help but think he should try to make a sphereflake next:


(image source: http://cliffandjean.com/cscie247/ )

Sphereflakes are fairly standard ray tracing test objects because 1) it’s easy to write a sphere intersection routine and 2) spheres are great for showing off perfectly specular reflections—one of raytracing’s strong suits.  The name sphereflake refers to the Koch snowflake, one of the classic fractals.  However, the graphics and art worlds’ fascination with reflection (particularly curved reflection) is certainly much older than ray tracers or Anish Kapoor.

One of the most famous curved reflectors in all of art history is the convex mirror in the Arnolfini Portrait:  (yes, it’s that little mirror in the center.  See the wikipedia page for a close-up.)


The Arnolfini portrait, painted by Jan van Eyck, is probably one of the most amazing paintings ever made.  With every fold of fabric, the grain of the wood window, and carefully rendered metallic surfaces, it’s hard to believe that it was painted in 1434!  Amazingly, Van Eyck convincingly captures the non-linear distortion of the curved mirror.  Not only that, but he even paints the tiny caustics being cast on the wall by the amber beads to the left of the mirror.  Wow!