Resolution controls the roughness or quality of the image and affects the speed of the simulation. Set it to a positive value. The default value is 1. If you double the value (by setting it to 2.0), the tool is subtracted from the block half as often. If you decrease the value, the tool is subtracted from the block more often. If the simulation is too chunky, decrease Resolution by half. If the simulation quality is acceptable, but it is running too slowly, double the Resolution.