Computer Vision - Recognition 2D complex shapes using OpenCV

How work this aplication? Firs time each configuration 2D shape is retained in the library as dxf file. Second time the system can be use to recognise new 2D shape from library. In this whay the aplication can use unlimited range of 2D shapes. Where it can be used aplication? Selection and metering of parts in the manufacturing stream. Automatic search and verification of parts in online library. Use in games of cognitive development of children.