footprints in the sand

anyone know how to make a character leave footprints or tracks in the sand as they walk? Andrew Price mentions this in his “making realistic rain” with dynamic paint but doesn’t go any further with the thought.

I have looked at several dynamic paint tutorials but can’t seem to figure it out how to leave tracks.

An object attached to the soles of a character’s feet could be used as the “Brush” for the Dynamic Paint, and the sand surface acts as the Canvas. As the feet hit the sand, they will leave a Dynamic Paint “print.” Baked as an Image Sequence, this could then be used to fake the footprints as a Normal modulation of the sand surface Material, or if you’re really ambitious, perhaps a Displacement. At least, that’s how I’d start out.

thanks for aiming me in the right direction, chipmasque. I’ll give it a try!