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Extracting STEP Geometry and Topology from a Solid Modeler: Parasolid-to-STEP



Thomas R. Kramer


Parasolid is a commercial solid modeling software system. It uses a manifold boundary representation. STEP (STandard for the Exchange of Product model data) is an emerging international standard. Included in STEP are proposed standards for Topology and Geometry (which provide the definitions of data types required for building boundary representations) and for physical files representing products. Parasolid-to-STEP is a software system written in the C Programming language for translating a Parasolid format boundary representation file giving the shape of an object into a STEP format file describing the same shape. The system handles elementary curves (line, circle, ellipse) and surfaces (plane, sphere, cylinder, cone, torus).
NIST Interagency/Internal Report (NISTIR) - 4577
Report Number


STEP, product model data, modeling software


Kramer, T. (1991), Extracting STEP Geometry and Topology from a Solid Modeler: Parasolid-to-STEP, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 19, 2024)


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Created June 1, 1991, Updated November 10, 2018