B-rep or boundary representation is a rendering technique for solid modeling. It is a popular approach to create a solid model of a physical object. Brep is that a three-dimensional object model is enclosed by surfaces or faces and has its own interior and exterior. It describes the shape as a collection of surfaces which separate its interior from the external environment. It is suitable for complex designs, Polygon facets are one of the examples of boundary representation.
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These are the following primitives of B-rep:-
1) Vertices: It is a point where two or more edges meet with another.
2) Edges: It is a line or curve enclosed between two vertices.
3) Faces: It is a surface or plane of the solid.
4) Loop: It is a hole in a face.
5) Genus: it is through a hole in a solid.