3D Solid Modeling And Boolean Operation Modeling Technique

The 3D modeling technique is the advanced technique in the Computer AidedDesign(CAD) system and the basic technique of model in virtual reality(VR). Ithas already become the main current of CAD technique quickly. The solidintersection, union, difference Boolean operation is one of the most importantand complicated problems in the solid modeling realm. It is one of the necessarymeans for constructing complicated solid in the solid modeling and gets extensiveapplication in many realms. This thesis takes comprehensive research on solidsmodeling and Boolean operation of solids, bringing forward revolving andextruding modeling and intersection, union, difference operation algorithm. Insolids modeling through analyzing its structure, the simply object is decomposed(into)a lot of basic solids such as box, sphere, cylinder, cone, torus, wedge etc.After the basis solid modeling we can get the 3D solid modeling of the objectby intersection, union, difference operation. For some complicated objects, itis difficult to be decomposed into some basic bodies. So, we can define the sectionoutline of object in the two dimensions geometry element structure. Then we getnew "basic body" by revolving or extruding in the 3D solid modeling and createthe 3D solid modeling of the object by intersection, union, differenceoperation. In the intersection, union, difference operation algorithm, theintersection operation as the basis, introducing many algorithms whichintersection, union, difference operation involve. The graphics intersection andjudging points in or out body is the basis which realizes intersection,union, difference operation, this thesis also introduces the algorithm of pointintersection and edge intersection and point and polyhedron position relationjudgement algorithm.