  We introduce an arbitrary order, computationally efficient method to smooth
corners on curves in the plane, as well as edges and vertices on surfaces in
$\mathbb R^3$. The method is local, only modifying the original surface in a
neighborhood of the geometric singularity, and preserves desirable features
like convexity and symmetry. The smoothness of the final surface is an explicit
parameter in the method, and the bandlimit of the smoothed surface is
proportional to its smoothness. Several numerical examples are provided in the
context of acoustic scattering. In particular, we compare scattered fields from
smoothed geometries in two dimensions with those from polygonal domains. We
observe that significant reductions in computational cost can be obtained if
merely approximate solutions are desired in the near- or far-field. Provided
that it is sub-wavelength, the error of the scattered field is proportional to
the size of the geometry that is modified.
