Use of freeform surfaces are very advantageous as they are more precise to keep file sizes smaller at higher precision. This kind of freeform surface patches (NURBS) is very suitable for surfaces without rigid radial dimensions like the body of a truck, the wings of helicopter or the hull of a boat. OBJ file format also specifies the tiling of surface geometry with free-form surface patches. Therefore, with fewer data as compared to polygonal tessellations, free-form curves used to generate a high-quality encoding of any 3D model without expanding the file size. As free-form curves are more complex than polygonal faces since, with few mathematical parameters, curved lines can be best defined by freeform curves. OBJ file format allows the user-defined free-form surface curves to specify the surface geometry of a model. Though tessellation increases coarseness to the model, yet It is necessary to discover the correct balance between size of a file and in its print quality. For surface geometry encoding of a model, a file stores the vertices and normal to each polygon. The OBJ file format facilitates the user to tessellate a 3D model surface using simple or complex geometric shapes. Following are three allowed formats having their own benefits and shortcomings: Tessellation with Polygonal Faces This format is quite versatile as it offers a number of choices to encode surface geometry. In 3D objects, encoding the surface geometry is a challenging job that OBJ file format accomplished very well. Wavefront Technologies kept this file format open source and neutral. The file format is open and has been implemented by other vendors for their 3D graphics application. Its version 2.11 is superseded by a newly documented version 3. Wavefront Technologies created OBJ file format for its Advanced Visualizer application to store geometric objects and 3D data. Though OBJ files declare scale information in a comment line yet no units have been declared for OBJ coordinates. The default order to store vertices is counter-clockwise avoiding explicit declaration of face normals. An OBJ file is usually an end product of the 3D modeling process generated by a CAD (Computer Aided Design). This format does not support animation or information related to light and position of scenes.

Both polygonal geometry like points, lines, texture vertices, faces and free-form geometry (curves and surfaces) are supported by OBJ format. Backward and forward transmission of geometric data is made possible through OBJ files. OBJ files are used by WavefrontвЂ™s Advanced Visualizer application to define and store the geometric objects.

Luxcorerender file obj