Hello !
I am making a site model, and I have imported the street lines as DWG. I have placed them o top of a rectangle base. When I am zoomed out, all of the lines are perfectly visible. However, when I zoom in, the lines are disappearing. I have tried many solutions but cannot get round to solving the problem. Any help would be much appreciated! I have also attached an image and a google drive link to my model: Base and street lines.skp - Google Drive
Thank you in advance for any replies !
Open GL changes the priority of displayed objects that are in the same or very near plane when the distance from camera increases. Perhaps the DWG is slightly below the rectangle, or parallel. The fastest way to keep your DWG displayed at all levels of zoom, move it up very slightly in the Z (blue direction) so that is above the ground plane. One inch or one cm should do.
It seems that there is no real solution to this problem, I will handle it this way then ! Thank you so much for your answer 
Hello, you should use the drape function to project your plan on the rectangle. It can be found in the Sandbox tools
You Can also draw a rectangle inside your street Line component instead of overlapping both, depending on how editable you then want it to be
If your .DWG lines are imbedded in the same plane this phenomenon will not occur. As @paul.millet pointed out drape is one way to achieve this. If the lines are in plane you can simply explode them and merge them with the raw surface below.
