Hi Guys,I just want to ask if it is possible to constrain 3d. for example i want rotate a rod which is one end is fix and if you add the distance of end to end it will automatically rotate base on the distance you put. of coarse your maximum distance will be when your rod is in horizontal position. Can you help me guys? Thanks in advance! 

Why are you posting in the Civil 3D/Map 3D forum?  This sounds like a generic AutoCAD 3D question to me.Re: Constraints in 3D.  Maybe this will give you something to think about...https://forums.autodesk.com/t5/autocad-2013-2014-2015-2016/autocad-3d-constraints/td-p/5565301