I had a mesh that I meshed to NURBS. The resulting surface was very ‘‘weird’’ and it wouldn´t split or serve as a cutting surface to split others. It also is hard to select, almost as if it is not there. So I exploded the surface. Some elements are normal and look like this:
if not selected the elements look exactly the same and both are called surfaces by rhino, even if their behaviour is completely different. Does anyone know how to fix this?
Upload a .3dm file with the input mesh and the NURBS surfaces. You can upload the file by dragging it to where you type a post, or by clicking on the vertical arrow button above where you type a post.
In the file you uploaded the mesh is red and the NURBS polysurface is brown.
Your description of the image above implies the red object is a NURBS polysurface.
Did you start with the mesh and create the NURBS polysurface from the mesh?
Or did you start with the NURBS polysurface and create the mesh from the NURBS polysurface?
This is likely to be display artifacts resulting from the objects being over 6 million units from the world origin. Rhino uses douple precison for all geometry calculations and this distance from the world origin should not cause problems with the geometry numbers. However the calculations for the display is single precision which can have problems with distances that far from the world origin. The solution is to move the objects closer to the world origin. (Changing the Cplane so that the Cplane origin is closer to the objects will not fix this type of problem.)
I changed colours to facilitate. I started with the mesh in red. Exploded it. Selected all to mesh to NURB and joined the result in a new polysurface (now in brown). The joined surface 4 or 5 wholes which I patched by hand, but the ‘‘weird’’ elements are unrelated to that patches.
I will try that, but we have being working with this for a while without problems, it is far a way from the 0,0,0 because we used geographic coordinations for placing the models where they should be.
From the file that is supplied, it’s impossible to tell how that object became bad. Running MeshRepair on the mesh object will tell you it’s considered “bad” but running ToNURBS on it doesn’t create a bad polysurface.
-wim
Thank you for the answer, wim. I wrote down this commands for use I got this mesh like this, but had to fix it to surface. I found a different fix, remeshing it and then meshing it to NURB.
I got this mesh like this, but had to fix it to surface. I found a different fix, remeshing it and then meshing it to NURB.