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PolyCAD

The .stl or stereolithography format is an ASCII or binary file used in manufacturing. It is a list of the triangular surfaces that describe a computer generated solid model. This is the standard input for most rapid prototyping machines. PolyCAD only supports the ASCII version of the format.

Supported Entities Import Export
Arc    
Box    
BSpline Curve    
BSpline Surface    
BSpline Suface List    
Circle    
Cubic Spline    
Frames    
Groups    
Image Plane    
IntelliCurve    
IntelliHull    
Interpolating Cubic BSpline    
Mesh    
Point Cloud    
Polygon List Yes  
Polyline    
Polyline List    
ShipLINES    
X-Topology Curves    
X-Topology Surface    
YachtLINES