Thread by @killsquadgame

It’s Saturday, so we’re gonna talk game tech! Binding of Isaac. No Man’s Sky. Killsquad. Different on the surface but, under the hood, a common approach. Today, we deep dive on procedural world generation for games! #gamedev #indiedev #IndieGameDev #indiegames #UE4 #unreal

If you want replay value, procedural is the way to go. Instead of building everything by hand, and enjoying it once, in a procedural approach you start with primitive elements, and rules to combine them, to build a game you can replay with a different experience every time.

This can be more or less complex. On one end, enter @NoMansSky, where everything is procedural, from plants to full planets. Here the load goes on the “rules” side, with exotic math paving the way. Wanna know more about it? This article is a great start: 3dgamedevblog.com/?p=836

Being more architectural/structured, Killsquad is simpler: we start with map “chunks”, and a rule system combines them meaningfully. The map generator has rules like “boss room goes in the end”, “combine harder and softer sections”. This is the Diablo III approach.

The tricky bit is not the map itself, but the game logic: where do we spawn monsters? Chests? How do we make sure there’s always a way to beat the mission? How do we propagate all of this through a network so 4 players see exactly the same?

The grand-daddy of this was Left4Dead, from which we took a ton of inspiration. Did you know L4D spawned monsters in “waves” to generate a tension-relax pattern? We still do the same! Check out this GDC paper, specifically slides 77 onwards:
steamcdn-a.akamaihd.net/apps/valve/200…

In our case, we were lucky to be using Unreal, which provides a lot of useful services. Specifically, check out this tech paper on the Gameplay Abilities System we used to do all this on a networked game and still survive ;-): docs.unrealengine.com/en-US/Gameplay…

The final pass is lighting it all. In a pre-built map, this is straightforward. But not so much if the map is built on the fly: we had to compute all lighting dynamically, including thousands of particles we added because… you know, VFX are cool. And it’s a sci-fi game.

Once the system works, you can expand it with new primitives and more rules. This is the case of the new Federation areas and units you’ll be experiencing next week. As it goes on top of the procedural engine, it increases replayability. Which is the goal.

Did you like this post? Then please share, RT, and comment. If you enjoy this type of content, we’ll post more soon. For a deeper-dive, check out this article on our Steam page!
steamcommunity.com/gid/1035827914…