What IS a Voxel??

[Dreamcube017]

Hi guys. I've looked it up and from my understanding it's like... a bunch of 3D pixels (cubes) stacked ontop of each other... so like tiny building blocks.

Is there a simple explanation of what it is? ...and possibly with visual examples to explain it.

I looked on Wikipedia and my mind got even more blown when I read this.

"A generalization of a voxel is the doxel, or dynamic voxel. This is used in the case of a 4D dataset, for example, an image sequence that represents 3D space together with another dimension such as time. In this way, an image could contain 100×100×100×100 doxels, which could be seen as a series of 100 frames of a 100×100×100 volume image (the equivalent for a 3D image would be showing a 2D cross section of the image in each frame). Although storage and manipulation of such data uses a lot of computer memory, this allows the study of spacetime systems.[citation needed]"

So uh... any nice simple explanations? Thanks.

[Grandmaster B]

Also look up "marching cubes" to get an idea.

[Spiraloid]

this isn't exactly accurate, but I use this metaphor to help me predict what a given tool will do.

think of it as a giant pile of 3D pixels stacked in a perfect cube, like bricks on a pallet.

some of the bricks are solid, some of the bricks are clear. the polygon surface you see rendered on your computer monitor is temporary, it's dynamically generated every frame when you paint. it is surface boundary between the solid voxels and the clear voxels.

if you know 3D well, instead of a thinking of a drawing as 512x512 image, think of a 3D drawing. a 512x512x512 "image".

[philnolan3d]

Well,imagine the Voxel room is actually made up of a three dimensional grid of invisible cubes. As you sculpt you're actually just turning those cubes on or off so to speak. The cubes that are "on" get surrounded by a mesh of triangles in real time. You can see the mesh being created if you hold the W key for Wireframe mode while you sculpt some. of course this is just a very simplified explanation. There is a pretty good bit of info on this page if you haven't seen it before:

http://www.3d-coat.com/voxel-sculpting/

Edit: Looks like Bay beat me to it.

[AbnRanger]

this isn't exactly accurate, but I use this metaphor to help me predict what a given tool will do.

think of it as a giant pile of 3D pixels stacked in a perfect cube, like bricks on a pallet.

some of the bricks are solid, some of the bricks are clear. the polygon surface you see rendered on your computer monitor is tempoary, dynamically generated every frame when you paint. it is surface boundary between the solid voxels and the clear voxels.

if you know 3D well, instead of a thinking of a drawing as 512x512 image, think of a 3D drawing. a 512x512x512 "image".

...and the triangular mesh that surrounds it is akin to shrink wrap on Bay's voxel pallet.

[Spiraloid]

...and the triangular mesh that surrounds it is akin to shrink wrap on Bay's voxel pallet.

or a blanket on a couch...

hence 3D coat.

[michalis]

So, a shrink wrap tool when importing an obj could be a good idea, as a filter, as cloth maybe.

This is the way I import complicated objs, when non manifolds exist or too many meshes one inside the other.

I tried the zbrush (adaptive skin) method and worked. The blender shrinkwrap tool works but not as accurate. I end up with a waterproof object ready for vox sculpt.

[Dreamcube017]

Oh I get it. So it's just like in paint when you draw on a black 512x512 picture, and you draw with a black line... those pixels turn black (or on) because a color is added. So in 3D, it's kinda like 3D pixels.

Thanks guys. I'll check out that Marching Cubes thing. I'll check out that skinwrap thing too. I don't think I've heard of that.

[philnolan3d]

Something like that. The word "voxel" comes from VOlumetric piXEL after all. Of course to be clear, 3D-Coat is one of only a couple 3D apps that use voxels for sculpting, mudbox and zbrush do not.