OBJ is a geometry definition file format (.obj extension) first developed by Wavefront Technologies for its Advanced Visualizer animation package.
The OBJ file format is a simple data-format that represents 3D geometry alone — namely, the position of each vertex, the UV position of each texture coordinate vertex, vertex normals, and the faces that make each polygon defined as a list of vertices, and texture vertices.
Vertices are stored in a counter-clockwise order by default, making explicit declaration of face normals unnecessary. OBJ coordinates have no units, but OBJ files can contain scale information in a human readable comment line.
An SKP file is a three-dimensional model created by SketchUp, a 3D design program. It contains a model with wireframes, shades, edge effects, and textures.
The SKP file enables conceptual designs to be created, viewed, and shared quickly and easily. When you create a new document and save it in SketchUp the SKP file is created to store the document and its contents. SKP files can also be used to store SketchUp components. Components may be made by you or another user and can be imported into an SKP document to be inserted into your model.
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 moreIn the ninth part of the series, we take a look at the effectively standard format for 3D graphics
Read moreCAD Exchanger imports and tesselates FBX, glTF, OBJ, PLY, and STL files, making them ready for further optimization by RapidCompact.
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