Parametric patches and volumes in function representation of geometric solids
نویسنده
چکیده
We take an approach to specify and control implicitly dened n-dimensional free-form solid primitives using parametric functions of n variables. Outside of the domain, the parametric function value increases or decreases rapidly that is not suitable to design geometric objects. In this paper, we introduce a functional clipping operation which allows a free-form primitive to be treated as traditional implicit primitives in set-theoretic modelling based on R-functions. We also introduce an extended B ezier clipping operation for fast inverse mapping in the case of the changed domain. Examples of set-theoretic, o setting, hypertexturing and metamorphosis operations on free-form primitives are given. Tessellation of trimmed parametric patches is explained as an application of our new geometric modelling method.
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