Bad Mesh and Curves Breaking Projected to Mesh


I am having some issues with projecting some street lines onto a topography mesh.

Here are the street lines before the projection:

Here are the street lines after the projection:

As you can see, several of these lines have been deleted. This is also happening with every other layer that I am trying to project onto this mesh, leaving me with a file that is too damaged to work with.

I found out that the topography mesh that I was given here is actually a bad object. I attempted to fix it with the steps listed here, under “Bad Meshes”. After I did this, the mesh did not read as a bad object, but the exact same projection error still occurred

Can someone let me know what I can do about this? Is the issue purely with the mesh, or is there something about my method of projection that is giving me these problems?

Thank you! (1.7 MB) .

Hello @alicemcgee97,

the mesh is not the best, the curves (mixed polylines and nurbs curves) may be another thing…You might also check your file tolerances under

DocumentProperties > Units > Model

since you’re working with meters 0.01 units might be too large to get better streets.
I’ve build the mesh as Nurbs, the projected curves look better, tolerances where like this:


Topo mesh as dense Nurbs surface: topo.3dm (2.2 MB)

When you _Project make sure to set the _Loose=_No option.