[Gmsh] Something's Wrong With my High Order Curved Surface Elements

[John Pease Moore]

Hi All,

I'm trying to create a very simple high order curved mesh of a sphere. When I generate the mesh in gmsh and visualize the surface, everything looks fine. However, when I take the mesh, read it into MATLAB and plot it myself, it looks terrible--it is no longer high order. The polynomial order is 5.

I have included three images: two of the sphere generated with gmsh, and another visualized within MATLAB.

I can't figure out what is causing the discrepancy. I have tried using both monomial and orthonormal (koorwinder) nodal basis functions, but that doesn't seem to help.

What type of basis functions does gmsh use? Is it producing its visualization using Bezier curves or nurbs? That's the only explanation I can think of.

I am using the following command to generate the mesh:
gmsh -2 -order 5 -hoOptimize sphere_generator.geo

Does anyone know what might be going on here? Any help would be greatly appreciated!

Thanks for your time!

John
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