In solid modeling and computer-aided design, boundary representation—often abbreviated as B-rep or BREP—is a method for representing shapes using the limits. A solid is represented as a collection of connected surface elements, the boundary between solid and non-solid.
Boundary representation of models are composed of two parts: topology and geometry (surfaces, curves and points). The main topological items are: faces, edges and vertices. A face is a bounded portion of a surface; an edge is a bounded piece of a curve and a vertex lies at a point. Other elements are the shell (a set of connected faces), the loop (a circuit of edges bounding a face) and loop-edge links (also known as winged edge links or half-edges) which are used to create the edge circuits. The edges are like the edges of a table, bounding a surface portion.
Compared to the constructive solid geometry (CSG) representation, which uses only primitive objects and Boolean operations to combine them, boundary representation is more flexible and has a much richer operation set. In addition to the Boolean operations, B-rep has extrusion (or sweeping), chamfer, blending, drafting, shelling, tweaking and other operations which make use of these.
AutoCAD DXF (Drawing Interchange Format, or Drawing Exchange formal) is a CAD file format created by Autodesk for AutoCAD more compatible with other programs.
DXF was initially intended to represent exact copy of the data in the AutoCAD native format DWG (Drawing).
It can’t hurt if we mention that DXF coordinates come always without dimensions so the user needs to know the drawing unit or has to extract it from the textual comments in the sheets.
A CAD file is an output of a CAD software, containing key information about the designed object: its geometry and topology representation, 3D model hierarchy, metadata, and visual attributes depending on the format of the file.Read more
Closing this year's work with U3D, 3D PDF, CATIA, Parasolid, DWG, Inventor, USD, and other formats support upgrade.Read more
In the fifth part of "How to build 3D web apps" series we examine alternative possibilities to create a fully fledged 3D web appRead more