r.ros(1grass) on Linux
The text 7076fb7a1b51, as Debian 10 (Buster) shipped it.
Generates rate of spread raster maps. Generates three, or four raster map layers showing the base (perpendicular) rate of spread (ROS), the maximum (forward) ROS, the direction of the maximum ROS, and optionally the maximum potential spotting distance for fire spread simulation.