RDG: Special Rooms in Caverns, Warrens, and Mazes

(Posted under duress in accordance with the OSR Blogowners Association standards.)

I’ve done some preliminary testing of the corridor generation and room generation techniques for a Random Dungeon Generator and noticed some rough spots: entirely too many traps. I will have to fix that in any final published version. In the meantime, I’ve been thinking about generating the zone special feature rooms or zone hubs. I’m not entirely finished thinking about these, an in particular I haven’t decided whether it would be better to connect the structure of the special room to the concept of the feature or keep them separate. I think for now I’ll restrict myself to thinking about structure in isolation, and I’ll take the structure types slowly as I ponder the possibilities.

I’ll start with special feature rooms for caverns, warrens and mazes. (Yes, I know I didn’t describe creating cavern tunnels and generic “rooms” yet, buut I’ll get to that soon. In the meantime, I’m just going to state that I see the special feature rooms for both caverns and warrens as being structurally the same.) While the standard rooms surrounding a zone feature are all squares and rectangles of fairly similar size, the zone feature rooms ought to have a chance for more irregular shapes: L- and T-shaped rooms, for example.

There’s an easy way to do this.

Imagine first that the area – subzone – with the special feature in it is a 10x10 square “geomorph” (100 x 100 feet.) The geomorph has four quadrants, and there may be a room are part of a room in each quadrant. Roll 3d6 and observe how they land in relation to each other: the arrangement will be either an L, a T, or all in a rough line. this tells you which quadrants have a structure present.

Each d6 represents one possible room. If two of the dice, or all three, match, merge these into one room. The dots on a d6 represent the shape of the room, similar to the way the spaces behind doors work, but in this case each dot is a 20 x 20 foot area of floor.

1. 20-foot diameter circular chamber
2. triangular room, 20-foot base & height
3. triangular room, 30-foot base & height
4. 40x40 foot square
5. 50x50 foot square
6. 40x60 foot rectangle

“Merged” matching dice will extend one of the dimensions. For example, this arrangement of dice:

4    4
5

Represents an 80x40 foot room spanning the north half of a geomorph and a 50x50 foot room in the SW quadrant. Merged triangles get trickier, since depending on the dice orientation, you will get either a larger triangle, a parallelogram, an irregular shape, or a trapezoid. for caverns and warrens, you should round the corners and curve the walls a bit, but mazes may have actual straight walls and sharp corners.

Another roll, which I will present in a future post, will allow for pits and high ceilings. If a room has either, roll 1, 2 or 3d6 depending on the number of quadrants the room spans to determine what the shape of the “basement” and “gallery” levels is. It might be smaller or larger than the chamber’s main level, and might have a different shape than the lower portion, perhaps even connecting to an upper or lower “sublevel”.

Written with StackEdit.