How would you call this feature in a NURBS modeler?

 From:  amur (STEFAN)
7934.1 
Hi all,

i'm currently interested to find the best way to create bas reliefs and came across the
awesome JDPaint software from China. I watched already several YouTube videos about
JDPaint and find it's functionality pretty impressive. One feature which i have never seen
before is in the video below at 45 sec.. How would one call this feature, i wonder?

https://www.youtube.com/watch?v=lA9GhmquhPE

Regards
Stefan
https://www.behance.net/futagoza