| With the development of computer technology,3D digital product modeling has been gradually used in a wide range of industry fields.3D digital modeling needs the support of graphics processing platform with function of efficient and high quality interactive display. HOOPS is currently the world’s most advanced and open type of3D graphics processing platform. It is an important significance for research and development of a system of3D modeling based on HOOPS with independent copyright.The paper first has some in-depth research on the architecture and working principle of HOOPS3DF. A3D graphics platform controlled by HOOPS is created by utilizing the HOOPS/MVO component in the original framework of JhSolid. Then an interface for data transfer between Parasolid and HOOPS is designed after study on the shape data output of Parasolid modeling kernel. Four kinds of rendering modes are then programmed by changing the attributes of segments. Capability of picking up the coordinate plane and topological surface is also achieved by using custom algorithm and Parasolid function. After that, a local coordinate is set up by making use of parameters of the construction plane, with the help of which the platform realizes the functionality of draft drawing. Two kinds of hierarchy segment trees for parts document and assembly document are created respectively according to the characteristics of product modeling within JhSolid. A recursive search algorithm for selecting part and subassembly is designed in order to implement other operations of assembly modeling. In addition, this thesis also discusses the dynamic interference detection in an assembly environment and a new GJK-based algorithm which lays foundation for subsequent research to solve the problem of continuous collision detection among convexes is proposed. Finally, two new lightweight file formats for publishing products are added into the platform. Both are easy to carry and be embedded in Web pages to facilitate network transmission, and have broad application prospects in3D digital design and display in future.The HOOPS-based3D graphics platform is proved to be feasible through programming, debugging and testing, and realize the above-mentioned function successfully. |
