Hi,
I have found this pg
which is almost what I need. But I can put wall at any angle and I want to constrain it to a specific value. maybe onMove to rotate the wall only with 30 degree or multiple of 30 and not free rotation like now. Can you help me please? Iām trying for more then an hour but I can;t figure it out 
Thanks
Not sure to understand exactly what you are trying to achieve ???
Oh, sorry about this
So if you click on time on the plane we have one point, for the second point I would like the pointer to snap from 15 to 15 degree (between the wall and X axis) and not like now when the rotation is free
Hi, here is
Beautiful, many thanks!!!