Unfortunately i had to format my pc and reinstall every Ubonto 18, Ros Melodic (with gazebo 9) and Moveit After reinstalling i went back to work on a gazebo simulation that was working just fine for the last few months. But now there are serious rendering glitches.  you can c in this very short video i uploaded: https://www.youtube.com/watch?v=GXTlLxVWmnQ&feature=youtu.be&ab_channel=YoavFekete

i tried to reinstall all, and to look for similar problems in forms but haven't found any! any idea is welcome i need it solved asap :)