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[Graham Macpherson <>]

Hello,

I'm meshing surfaces using the implicit surface mesher and testing it with 
simple smooth shapes.  Using the example 

    examples/Surface_mesher/mesh_an_implicit_function.cpp

I've created a fairly fine surface of a sphere using the criteria:

        30.0, // angular bound                                                
                         
        0.01, // radius bound                                                 
                         
        0.001  // distance bound  

The surface is not smooth - it has an "orange peel" look.  Plotting the 
radius 
of each vertex of the triangulation shows the magnitude of error of the 
triangulation point positions from the expected radius of 1:

    fineSphereSurfaceWithRadius.png

Creating a coarse surface with criteria

        30.0, // angular bound
        0.1, // radius bound
        0.1  // distance bound

Results in:

    coarseSphereSurfaceWithRadius.png

where the magnitude of vertex error is similar, but in the fine case, the 
same 
radial vertex position error in a smaller triangle creates a bigger error in 
the normal direction, hence the uneven look.

Is this the result that is expected? and is there anything that I can do to 
improve the conformance of the triangulation points to the expected sphere 
function?  Am I missing a tolerance adjustment somewhere?

It isn't a write precision/truncation problem, as I've set the precision of 
the ofstream to 15.

Thanks,

Graham

Attachment: coarseSphereSurfaceWithRadius.png
Description: PNG image

Attachment: fineSphereSurfaceWithRadius.png
Description: PNG image