Rendering unconnected edges I have a 2D base image on which I'd like to overlay a set of edges (several thousand), where each edge has a value determining its color.

For example:



My plan is to add each edge as a separate object with a custom property; then a single material across all edges can use the custom property to determine color.

The bit I'm having trouble with is actually getting edges to render. I was hoping that a wireframe modifier would give the edges enough geometry to be visible to the camera, however edges without associated faces don't seem to survive the modifier.

Is there a good way to get these edges to render?
Cycles

I don't know of any way to render edges like this natively in cycles, however the screw modifier can add geometry to edges:



It's a bit of hack, but I don't know of any faster way to add faces to edges using modifiers (it's not actually that bad, in most other cases using the screw modifier you would probably use only edges anyway).

Blender Internal

You can render edges using a Wire material:



Opengl

Of course, the viewport can render edges, however you are pretty limited in terms of controlling the color..



This patch may help though.