I’m making a text-based adventure which sends the player along different paths depending on their choices. Each scene is like a node in a directed graph. Each node has a time step which is equal to the number of nodes prior + 1. There is a maximum of Tn nodes per time step, say 5, and so you can visualise this in this way:

I want to generate paths like these.

Where a node points to more than one other, that could be called a fork and where two point to one, that could be called a merge.

At any particular timestep there will tend to be Tn / 2 paths, only rarely going down to one or up to Tn.

Does anyone have ideas or know of any similar work?

(One small issue – paths never cross – that is, those on the left stay on the left until merging to the right. And there’s no wrapping from far left to far right. Because of this, it seems like nodes on the far left or far right of a timestep will have a smaller probability of merging. Is this avoidable?)