% Interactive vector field on a spherical surface.
%
% Displays a dense divergence-free tangent vector field on a sphere.
% The field v = (x(y^2-z^2), y(z^2-x^2), z(x^2-y^2)) is the surface
% curl of F = xyz: eight swirling vortex regions separated by saddle
% points at the cube-face centres.  sphere(16) gives 6 x 16^2 = 1536
% arrows.  Use the Arrow scale slider to resize; drag to rotate, scroll
% to zoom.

mip load --install flatironinstitute/flatironinstitute/surfacefun

dom = surfacemesh.sphere(16);  % 16-point Chebyshev grid, 6 patches

vector_field_viewer(dom);