I was thinking about voxels and was wondering, if they’re just 3D pixels then can blender do them by just placing cubes?
I made a tank, is it a voxel tank?
blend:
http://www.mediafire.com/?db1bio5jwbnouug
Attachments
More or less, yes you are right. But you would need a lot of them and a nice concept of storing the data and building/deleting many voxels per frame.
A nice small voxelgame is announced (not in blender), that’s a nice example how a small voxelgame could be designed.
Voxatron: This is Voxel Madness
Watching that trailer is what gave me the idea 
Honestly, if I were building a voxel based game I’d just fake it rather than try and figure out a way of getting it running smoothly. I just thought that it was an interesting little attempt.
Wow, that looks sick! Interesting…
The trick with voxels is it takes so many to make anything decent, that if you just placed cubes it would bring any computer to its knees in no time. Generally the technique is essentially to place all the cubes, and then delete all the interior faces so only the outside is visible (and generally also smooth out the form)
For example, if you made a flat area 80x80x4 voxels (IE pretty small and very shallow) just placing cubes would amount to 153600 quads. If you cull out the interior faces, then you just have 6400 quads.
[edit] it’d be really cool if you saved the tank as a point cloud, and then placed the cubes in game dynamically- so if it rotated, the cubes would still be fitted to the grid of voxels.
That’s definitely what I’d do but I was thinking that’s probably cheating. From the trailer linked above it seems that something else is being done to generate the environment. I’m thinking that true voxels are something different to what I’ve done above and that the BGE doesn’t have the capacity to generate them.
Still it doesn’t need it. With the exception of the cool scrolling effect of the trailer true voxels don’t seem to bring anything to the table that faked ones do.
Hmm… I’m thinking that the next best thing to deleting unnecessary interior faces are to delete unnecessary interior cubes.
You would need a special voxel 3D engine. BGE is not the right solution. Blender could be an exporter which could convert Poly models to voxel data.
For a real voxel scene you would need Billions of voxels.
One other voxel engine is the Atomontage Engine:
http://atomontage.com
Very cool videos in the DevBlog:
http://atomontage.com/?id=dev_blog
“The Future Is Volumetric!” 
Using voxel is a complete different mathematical model.
It is volume based rather than surface based (as used by Blender and the most 3D games).
If you look at your hardware you will notice it supports surfaced based 3D mathematical model.
To make it short:
- complex voxel technique is mostlikely to slow for games or with less quality.
- you still could use a mix as you already do
Just a remark:
You will find volume based models (not just voxels) in science and industry.
Usually the visual representation is surface based. To make that possible the volume model is converted into a surface model.
I hope it helps