Figure 10

Illustrations of solutions to examples with curved characterics. (a) The distance field in presence of semi-permeable obstacles organised as nine walls (examples ${\mathrm{Ex}}_B$ and ${\mathrm{Ex}}_C$). (b) Three-dimensional visualisation of the distance field obtained by solving the chequerboard velocity problem (example ${\mathrm{Ex}}_D$). (c) Two-dimensional planar cut through the velocity-cubes distance field (example ${\mathrm{Ex}}_D$).