Clipping plane, the view distorted and unknown lines displayed

clipping plane, the view distorted and unknown lines displayedScreen Shot 2019-12-21 at 4.21.39 pm

Can you run SystemInfo in Rhino and post the results here?

sys.txt (3.5 KB)

Hi - this is a known (but rare) issue on certain Macs. I have added this thread to the bug tracker item (RH-54879) so that you will be notified when the problem is solved.
-wim