Weird graphic glitch

hi!

I’m pretty new with Rhino and don’t have a lot of experience. When adding a texture/picture to my extrusion and I look at it through render view (or when I actually render it) it keeps showing these weird graphical glitches that I can’t seem to get rid of. Anyone that knows how to fix this? I’m running on a 2021 macbook pro

Thanks in advance.

that usually happens when you have 2 surfaces/faces at the exact same position. what i usually do is move one surface with the texture a little bit or remove one face and not join, so that the here knows as “z fighting” stops.

Could you maybe simplify what you mean? I’m very new with this all and don’t really understand what you mean with 2 surfaces at the exact same position. are two surfaces overlapping or connecting weirdly in some way?

please post your file that people can tell exactly whats going on.

there is nothing more i can describe, its just 2 surfaces at the exact same position, though one can be bigger or part of a polysurface but if they meet at the exact same position you will get these glitches.

if you want to know the entire story, Nurbs surfaces (which are the objects usually generated by Rhino) are respresented as mesh, and these meshes have slightly different polygons, hence creating polygonal glitches.