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Problem statement

Implementation of the solid modeler starts with kernel database for manipulation of CSG tree. Kernel also consist of engine for calculating intermediate objects when traversing CSG tree to produce the final object as a result of Boolean operations. Several approaches can be used when implementing CSG engine. Typically we must balance three conflicting goals: efficiency, robustness, and accuracy. The main problem in CSG is calculating surface intersections. Number of different primitives dictates robustness and effectiveness of the intersection routines. High number of different primitives leads to high number of intersection functions and thus a big CSG kernel prone to errors.

User interface (UI) and extensibility is another multi way approach for connecting user and computer. Ease of use is ongoing research field comprising current state of the art hardware and software. Only few standards for 3D graphics exists. This is especially true if we want high performance graphics. In the area of cross-platform UI interface the solutions are only platform dependent. Some portable proprietary UI libraries exists and must be evaluated to suit the needs of a mixed case of solid modeler where we typically have graphical 3D window and a separate toolbox window.



Leon Kos
Wed May 27 11:00:46 CEST 1998