View Full Version : solid or surface models??

08-09-2004, 10:38 PM
Hi all... I'm new to both LW and this forum, both seem great, but I've encountered some frustrating issues with importing solid models from form-Z.

Is there a way to surface just one polygon of a solid? For example, if there's a wall that's concrete on the exterior and drywall on the interior -- can I somehow pick and surface just the interior polygon or do I need to create a new, slightly offset surface polygon for the interior wall?

All of my cgi experience has come from making solid models of architecture in form-Z so LW is very foreign to me. What is the conventional wisdom on solids vs. surfaces? Any help would be greatly appreciated.


08-10-2004, 12:13 AM
Well, reading the manual can help a lot... but anyway, here goes:

a) Select the polygons you want to surface.

b) Hit "q".

c) Type in a new name in the window that comes up.

You're set. Your new surface name will appear in the surface editor and from there you can adjust its parameters.

LW also does not use surfaces (I mean CAD surfaces with parametrical infinite resolution). LW uses polygons for everything and anything. In contrast to solids or real surfaces that limits the options for certain operations such as booleans since all information must be derived from existing points in space. Mainly this shows in the precision or smoothness of such things. A good example would be a simple cylinder drilling into a box - if you do that in a CAD/ design program and then export it as a mesh, the layout of your triangles would be different from a pure polygonal boolean operation. Since CAD progs maintain more information about their objects they will try to match the original contours more perfectly and adaptively fill their parametric surfaces with triangles whereas a polygonal tool will only cut up, delete and rearrange existing polygons. Anyway, in your case I wouldn't worry about that to much since you seem to do all your modelling in formZ. Just see to it, that you always export a clean mesh to Lw and you will be happy.