This image was computer generated by artists and historians: it is part of a virtual restoration of the House of the Poet in Pompeii. Cave canem means beware of the dog.

The image on the next page, also computer generated, is the atrium, the central room that has part of the roof open, with a pool below to collect rain. From there, rainwater travels through pipes leading to tanks.

Around the atrium are the doors to other rooms.

Link: https://www.youtube.com/watch?v=R42ykXaQd94