The best thing about openDDL are its multiple file formats which enable you easily use it with other softwares like Solidworks, AutoCAD etc..it's free so no worries of cost! I have seen some people using this software but they were not really able too understand how things work because there was just way more options than what one could read through at first place!. So try before buying if possible as i did!! It helped me solve my problem regarding compatibility issues between two files types (SolidWorks & CAD).
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