Parametric feature based modeler
From Wikipedia, the free encyclopedia
A parametric feature based modeler is a Computer-aided design (CAD) software package that uses either a constructive solid geometry (CSG) or a Boundary representation (B-REP) modeler that allows a user to refer to features instead of the underlying geometry.
A feature is a term referring to higher order CAD entities. For example, given a 3D brick with a hole, the hole is considered a feature in the brick to reflect the manufacturing process used to create it, rather than referring to the hole by the mathematical term cylinder.
Parametric feature based modelers use change states to maintain information about building the model and use Lisp expressions to constrain associations between the constructive solid geometries. This ability allows a user to go back to the feature history and make a modification at any state and to regenerate the model's boundary representation based on those changes. This ability is called a transmigration operation.
