An introduction to graph rewriting for procedural content generation

Graph rewriting is a great way to generate interesting procedural content for games, suitable for generating both grid-based and non-grid-based maps, quest structures, and more. In this introductory video, we'll look at what a graph is, how graph rewriting can be used to generate content for games, and what some common techniques and usages look like.

Intro: 00:00
What is a graph?: 00:42
Graph rewriting: 02:30
Generating a graph: 04:09
Common uses: 05:26

And here's a few links you might want to check out regarding implementation:

[NateyC]

Simple explanations and pleasing diagrams, who could ask for more?

[Kaznerh]

How could I *not* subscribe with such wonderful visuals and editing? Great video

[haydenap]

Always look forward to your videos. This has been really interesting, thanks for including extra links.

[pixtrick]

That was exactly what i was looking for. On top of that, that was brilliantly explained. Thanks mate

[pavlovsdoguk]

your stuff on Graph rewriting is awesome. Subbing for this content.

[Sean-gxsf]

Damn, first image is the FTL map; you know your stuff

[pokelizardo]

Great explination, a nice introdiction to graph rewriting.
What would you say are biggest pros and cons of graph rewriting for pcg compared to other techniques?

[_mickmccarthy]

Nice! I spent quite some time running through Joris Dormans' papers on graph grammars, could've used these videos around 5 years ago! ;)

Keep up the awesome work!

Not sure if you've come across it before, but there's a great Zelda dungeon generator project based off his work created by someone called Beck Lavender. Definitely worth checking out if you haven't already.

P.S. Haven't yet watched the whole video (but did see Unexplored get a mention!), so apologies if it's already covered!

[deeri]

How would you store a graph in Godot? Its the multi paths that Im not sure about, a simple tree is just children, but when a node can have multiple connections how would you store that

[SpudMackenzie]

Heads up, the metazelda link in the description appears to have died.

[Aleamanic]

what is that game at 0:39 in the video?

[Nesetalis]

This video feels like the underpants gnomes... "first I have some nodes, then replace nodes by color and connections." "???" level design!"
What is the aim of these replacements?
Now that you have a random smattering of colored nodes, what are you doing with those nodes to generate rooms? Are edges corridors? Doors? Are hallways a node?
And not once do you mention how you might program something. What is the underlying data type, how is it structured, how is memory allocated? What is the processing and memory cost of generating one of these graphs?
Implementation detail, even as an example would be nice.