Based On Two-dimensional Information Of The Virtual Three-dimensional Modeling Techniques

When a new product is designed in the ideas and studied whether it would be developed, we hope that it can be trialed and tested such as intervene checked, property calculated, framework and kinematics and dynamics analyzed, third dimension showed. Modeling 3D virtual solid is the base of the studies, trails and tests.The engineering drawing, made up of the three views, have been a general method expressing the 3D solid completely with 2D information in engineering project. Modeling 3D solid is intricacy, so it is necessary that a conversion is set up from engineering drawings to 3D solid model.A 3D solid is made up of a series of 3D features, so the key task is how to recognize the 3D feature information from 2D drawing data.After studied the algorithms of the previous scholars, the paper brings forwards a method about 3D reconstruction of virtual solid, based on feature-recognition from the DXF drawing data of 2D orthographic views.The paper analyzes the framework about the data of DXF drawing, and gets the 2D drawing information, and sorts the drawing elements in order to recognize 3D features conveniently.The DXF data of 2D information are preprocessed, the three views are recognized automatically, and the project center is found, so the difficulties of feature reconstruction are depressed and the efficiency of the algorithmic is increased.According to the rules about orthographic projections, a method of 3D feature recognition is made, which recognizes 3Dfeatures not only by 2D drawing elements but 3D solid.With Boolean calculation of 3D feature solid, the solids are reconstructed by OpenGL technology in Windows Visual C++ 6.0. It can be used farther in studies and tests later.The method searches the information of 3D features from three-views drawing, and pre-processes the 2D data, and generates 3D solid with OpenGL, so the method of 3D reconstruction in this paper is general suitable and practicability.