The attached image shows the nature of 3D SLICER's voxel-to-.stl-triangles
construction scheme on an enlarged scale, with and without 'smoothing' used
there. The same number of triangles are created either way.

I purposely sliced a POV-ray cone object at a very *low* resolution, 50 X 50
pixels with 50 slices.  The exported .stl file is shown in Meshmixer and
Ultimaker CURA. Note that on curved exterior surfaces, the voxels join to their
neighbors with a 45-degree tilt of triangles. In my opinion, this is an
advantage-- the surfaces are not simple 'stacked boxes'. With *high*-resolution
image slices, those tilted triangles become so small that even sharp model edges
are retained.

The tip of the cone ended up as four voxels, not one; that was my mistake with
the image resolution I chose. 51X51 pixels would have produced a single-voxel
tip, I think.

This particular cone object illustrates an interesting fact about the slicing
scheme itself, and how it relates to 3D SLICER. In POV-ray, the cone was made
with a 1-unit diameter base and 1 unit tall--- which happens to result in an
exactly cubic bounding box there, behind the scenes. Since it *is* a cube, the
slicing image dimensions and number of slices should be in a 1:1:1 ratio-- for
example,  500X500 rez with 500 slices (assuming the object 'fills the view' in
the renders). POV-ray's messages pane is not really needed to get the proper
ratio in this case-- the result would be a perfectly-proportioned cone due to
the automatic camera in my slicing code.  The same would happen with a sphere--
a cubic bounding box again. This little fact initially confused me as to how the
app was processing the *number* of slices I made-- my test objects had
different-sized b.b.'s with just a few being cubic by chance, and I didn't
realize the significance of the difference at first.  It's fundamentally because
the voxels in 3D SLICER  are 1mm cubes themselves, by default. But most objects
will have an oblong bounding box, not cubic-- which affects the number of slices
required, as each slice represents a single voxel's height. The wrong number
distorts the model.

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