Re: Selling RP, color questions

From: Stephen J. Rock (
Date: Thu May 07 1998 - 05:12:19 EEST

Innomation Systems & Technologies Pte. Ltd., wrote:

> hi list,
> using Octree encoding seems like we are trying to create a STL entity based
> on the lighting and texture of the object as seen in the CAD program.

We must be refering to two different things. The octree encoding mentionedin
my previous reply has nothing to do with facet representations such as STL
or elements of visualization such as lighting or texture.

It offers a more efficient means of defining a solid using the concept of
spatial occupancy enumeration (a matrix of cubic cells with some material
"value", be it defining color, composition, properties, or the lack thereof).
The interested can find more in Michael Mortenson's book titled Geometric
Modeling (Wiley, 1985), among others.

> but in reality...having the computer graphics visualisation will be very
> different from the manufactured part.

This is generally true; however, there are two kinds of colored parts
toconsider: colored only on the surface and colored throughout the 3D
object. Using the same representation for each case may be less than


Stephen J. Rock
Center for Automation Technologies
Rensselaer Polytechnic Institute
Troy, NY 12180  USA
(518)276-8652  Fax -4897

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