Ping pong ball

Ping pong ball

When I give mixed reality presentations in Chalktalk, it bothers me that the 3D computer graphic objects floating in front of me look fake. The problem is mainly that the lighting of the virtual object doesn’t match the lighting in the room I’m actually in. You can see an example of this here:

To fix this I implemented in Chalktalk an old rendering trick that I first started using many years ago. I just hold up a ping pong ball to the camera:

Then when I render any 3D virtual object, I use that image of the ping pong ball as a reflection map to light my virtual object:

From there I can add colors and textures. But meanwhile, the object has the right lighting for the room I’m in.

Ping pong balls are fairly shiny. If I wanted to create something that looked less shiny, I would replace the ping pong ball with something less shiny, like a rubber ball.

Ken Perlin
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