INFO: Polygon Modeling and Reduction
  
PSS ID Number: Q180225
Article last modified on 02-05-1998
 
IRIX:3.7; WINNT:3.7
 
IRIX winnt
 

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The information in this article applies to:
 
 - Softimage 3D for IRIX, version 3.7
 - Softimage 3D for Windows NT, version 3.7
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SUMMARY
=======
 
This article provides a brief description of Polygon modeling and Polygon
reduction.
 
MORE INFORMATION
================
 
Polygon Modeling
----------------
 
Polygon modeling allows you to treat each polygon on an object as if it was
a separate object with its own axis and independent controls. The controls
for translation, scaling, and rotation can affect each polygon separately.
You can select a polygon with rectangular toggle by tagged vertex or by ray
casting, which only selects the polygons facing the camera. Beginning with
version 3.7, you can view a shaded model and also see the lines, vertices,
and textures. This makes modeling a lot easier.
 
For example, you can start with a simple cube, add vertex, duplicate some
of the polygons, pull and scale them, and then smooth the object by
applying Effect->Rounding.
 
Polygon Reduction
=================
 
The final object is a smooth, high-resolution polygonal object that you can
use for cinema, a trailer, or for printing. If it is needed for a real-time
application, you can apply one of the polygon reduction tools; this can
reduce the polygon count by almost 50 percent with a minimal quality trade-
off.
 
SOFTIMAGE 3D has two polygon reduction tools: Optimize and Rule Based. With
Optimize, you simply set the target count and the software does all the
computations. Once you learn the basics of polygon reduction, it is more
efficient to use the Rule Based tool. The Rule Based tool allows you to
reduce the entire object or tagged points. It is also possible to preserve
curves and hard edges, and reduce the polygon count based on specific
criteria (radius, length, area, height, angle).
 
REFERENCES
==========
 
If you have any questions concerning the information contained in this
article, contact support@softimage.com by e-mail.
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Keywords          : si si3d si3dmod
Version           : IRIX:3.7; WINNT:3.7
Platform          : IRIX winnt
Issue type        : kbinfo
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Copyright Microsoft Corporation 1998.