Drawn lines in shaded view not consistently displaying in view

Never had this happen before, lines I have drawn lines that are not always showing up in shaded view. Sometimes their their there some times not. I do have “show lines turned on” in shaded view port in properties. . They are showing consistently in ghosted view. When I switch into shaded view the lines are there for a second then are gone. Any one have a clue whats going on in this type of situation? maybe I changed some other setting?


We would need a simple example file with a surface and a few curves that demonstrate the issue to know for sure.

As John said an example file would help. You can upload it using the vertical arrow above where you type your post.

Are these curves supposed to be on a surface? If so is the surface open or closed? Do they disappear in all viewports?

One possibility is the curves are not exactly on a surface and are being obscured by the surface.

Hi Flubber - I guess the first thing is to check a Shaded mode is set to defaults - you can set that in Options > View > Display modes. If the problem still occurs, and if it is not all the time, then finding a case where it is repeatable and sending that in here would be the next thing…