Abstract: Based on mufti-contrained theories of graphics, we defined the shape of detail drawings by mufti-contrained method and had share of both detail drawings and assembly drawing by mixed data structure of tree and list. On this basis, we made use of different mathematical representation of lines and derived out the most simple algorithm for clipping lines against an arbitray polygon window. In this way, the information of detail drawings is automatically transformed into the information of assembly drawings and the integration of determining, finding out the intersection of lines and testing assembly visibility is implemented. Thus, we not only resolved the problem of arbitray complicated assembly drawings, but also improved mechanical CAD level.

Key words: Assembly drawing, Mechanics CAD, Part drawing, Gear profile error, On-Machine Measurement, Scheme Generation, Multi-axis CNC machine tool