# How to combine embedded generated graphs in a finite 2D plane?

I'm pretty new to working with graphs but I'm looking at using them to create the world map for our game (a text mud with rooms/nodes and paths/edges between rooms). There are a number of interesting small-world generators, for example Watts-Strogatz (http://en.wikipedia.org/wiki/Watts_and_Strogatz_model) that I'd like to combine.

My question is how to combine different generators. All the rooms will have coordinates in an XY plane (the rooms themselves won't have real dimensions). I can easily generate a graph, and then laying it out I can work out the XY coordinates of its nodes. But then I'd like to generate a new graph and connect at least one of its nodes to a node on the previous graph.

My first idea is to figure out the XY bounding box of a graph, and use that to place it in the larger XY plane next to the previous graph (kind of tiling the graphs). Are there other methods I should be aware of?

• More detail please? You can trivially join two graphs by sticking an edge between a random nodes from each. I assume you're looking for something more complex, but I don't understand what it is. – Anko Feb 21 '15 at 11:13
• Maybe I should rephrase the question as 'How to combine embedded graphs in a finite XY plane'? So I have a fixed size 2D map and I'm generating graphs and embedding them there. – georgek Feb 22 '15 at 21:05