Autodesk LIGHTSCAPE Manual page 201

Model Efficiently
Model surfaces in the most efficient way possible.
For example, when creating a revolved surface, set
the tessellation complexity of the object to a coarse
value, and use smoothing within Lightscape to get
the curved effect.
Complex geometry processes faster when
modeled efficiently, as shown on the right
Model Surfaces as Regular Polygons
Many shadow artifacts are the product of meshing
strangely shaped surfaces (such as adjacent, long,
thin, triangular surfaces). Rectangular polygons and
equilateral triangles produce the best effects.
Surfaces with openings are best modeled as
shown on the right
Avoid Overlapping Coplanar Surfaces
Overlapping coplanar surfaces may display artifacts
or noise when processed. In the Preparation file,
coplanar surfaces appear to blink or sparkle when
you orbit around the model. Delete one of the
surfaces, and verify the orientation of the remaining
surface. For more information, see "Working with
Surfaces" on page 95.
Modeling Guidelines
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