I've started working with volume textures. I'm able to create them procedurally or with other images, but now i'm stuck with a question: is it possible to render a mesh (a simple model like a car, a ball or whatever) in a volume texture? I've seen some papers about raytracing and medical image rendering that use volume texture, and they render very beautiful images (there's a Stanford dragon somewhere). How do they managed to do that?

Medical images and the Stanford models come from scanning. Medical imaging is often slice based originally. Other types of scanning can be reconstructed to be slice based.

You may be able to create a sliced image from a model, by rendering the model limited to various Z ranges, but I imagine that you'd come across the problem of the mesh model not having any real volume, so it'd mostly be empty inside. Medical images and procedurally created objects don't have that problem.

Anyway, if you manage to get this to work, I'd be happy to see the results.

@ET3D: for now it's not important if the model is empty, i'm rendering it only from the outside.
What do you mean with "You may be able to create a sliced image from a model, by rendering the model limited to various Z ranges" ?

@Kambiz: thank you, its a very good tut, but says nothing about creating volumes...

Quote:Original post by b3rs3rk
@ET3D: for now it's not important if the model is empty, i'm rendering it only from the outside.
What do you mean with "You may be able to create a sliced image from a model, by rendering the model limited to various Z ranges" ?

He means splicing the model at certain Z positions and then storing the image.

A very simple way to do this would be to increate the NearZ clip plane to do your "splicing", then take a screenshot and save it at each splice.

However, you'll run into the problem of a model having no interior. there won't be anything to "see" inside them, and backsides of polygons are culled so they won't even be rendered. Which kind of defeats the purpose.