A constraint is created between the generated element and the 2D
				  element. However, note that, no constraints can be created between 2D and
				  generated elements when:
				
				  - The 
					 front view of the 3D revolution surface is not
					 perfectly positioned as in the example below:
					 
				  
 
				  - The 3D surface is not a regular one as in the example below: 
					 
				  
 
				  - An interactive 2D line cannot be constrained with extremities
					 or midpoints of any generated line element, except with generated curves.
					 
Extremity
					 
					 
					 Midpoint
					 
					 
				   
				  - The view containing the geometries is not up-to-date.