Fig. 2
From: Fast rapidly convergent penetrable scattering computations
An illustration of the grid placement for a three patch decomposition of a bean shaped domain (given by, e.g., the blue curve in the top-right subfigure.) The figure shows on the top left—the grid over two boundary patches; at the top right— grid over the interior-patch region; at the bottom left—union of the grids over the boundary- and interior-patches; and at the bottom right—the auxiliary polar grid encompassing the domain