Understanding pointyness

I want to create a shader that “highlights” the edges of an object. In this sample I wanted the red highlighted ring edge highlighted. I found screen shots on the net doing this with the node setup below but it did not work for me.

I also tried with adding bevel but still it did not change behavior was wanted. When I move the ramp nodes around I cant get the highlight to focus on the edge.

What am I doing wrong? It seems to work from what I see on the net, but something must be missing or I am misunderstanding this node setup.

Is there another way to achieve this?

Pointiness explained:

An approximation of the curvature of the mesh per-vertex. Lighter values indicate convex angles, darker values indicate concave angles.
Cycles pointiness attribute

Another good source is Cycles Encyclopedia - Inputs

Test file:



thx, the cycles encyclopedia is very helpful.