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adk
09-18-2011, 11:06 PM
Can someone here that's node savvy answer this question for me as I'm a bit lost as to why I can't displace an object, via the surfece editor, using a cubic map.

I'm basically trying to create a nice stackstone wall without having to model it by hand (nor UV if I can help it). So I create a sub-d object, slap a cubic (colour/normal/ spec etc) map inside the surface node editor, all well and good, then I try to displace it along surface normals using spot info scaled with the grayscale cubic displacement map. It always displaces along a single direction (planar projection).

If I use the same cubic map setup inside the nodal displacement editor it displaces correctly, along normals.

If I simply change the first setup, inside nodal surface editor, from cubic to UV map it displaces correctly.

So while I can get it to work just fine with the other techniques, and other projection modes work just fine btw, I simply want to get my head around why cubic maping doesn't work in this case ?
Or maybe it does & I'm missing some vital ingredient. It would just be nice to do it all in one place that's all.

dpont
09-19-2011, 12:56 AM
Not specifically in nodal surface,
It seems to be a limitation in Bump Displacement,
it is evaluating without the spot normal,
just with the local and world spot position
like in a procedural texture,
so no possibility of projection axis detection

Denis.

dpont
09-19-2011, 01:23 AM
Even if your setup is in a surface or texture editor,
for displacement and surfacing
the spot/point normal doesn't come at the same time
from the same process.

Don't remember exactly when Bump Displacement
was added in Lightwave,
I suppose that was before the implementation
of point normal in the LW9.0 mesh info,
so you could ask for a fix.

The point normal is not always calculated by Lightwave,
or simply averaged, not matching the surface smoothness setting,
with possible variable results in preview and render,
this could explain subtle differences between
Bump Displacement, Normal Displacement etc..


Denis

RebelHill
09-19-2011, 05:03 AM
You dont need to use spot info if using the displace input in surface editor... bump displacement will automatically displace out along the surface normals... all you should need is the correct projction, and hook it in.

adk
09-19-2011, 05:43 AM
Cheers for the explanation Denis. Makes sense why I can't get it to work.

RebelHill...cubic is the only projection which does not work in this case, as in displace along surface normals like you describe. Cylindrical + spherical + planar all work. I thought I'd give it a helping hand with a spot info added in but with no luck. Unless you mean something else.

Sensei
09-19-2011, 09:32 AM
RebelHill...cubic is the only projection which does not work in this case, as in displace along surface normals like you describe. Cylindrical + spherical + planar all work.

Because these projections don't need info that's missing, which cubic mapping requires..


I thought I'd give it a helping hand with a spot info added in but with no luck. Unless you mean something else.

Try this:
make uv map, simulating cubic mapping in Modeler
pick up UV map in bump surface settings
Enable bump displacement.