Introduction
Fallout 4 uses modular kits to create its levels.
Joel Burgess and Nathan Purkeypile worked together using modular techniques.
They explain what it takes to create kits like these.
This is my synthesis of publicly available GDC Vault talks on Fallout 4’s level design, not original reporting.
Bethesda has been using modular kits for level design for a long time.
This goes back to Daggerfall which already used them.
Later games continued this trend.
In Morrowind everything was snapped to a grid.
This, however, made the player feel the presence of the kits.
As they were always going into cardinal directions.
Modular Level Design 101
When creating a kit there is a really important concept:
The Footprint
This refers to the grid, size and shape of the pieces.
Staying inside the footprint is important.
Going over it means overlapping with other kit pieces.
Another important topic is:
Pivot Placement
Having a proper pivot can really help Level Designers.
When creating a kit one may think that hero pieces are the most important.
( Hero pieces refer to story specific assets or assets that are important or mark landmarks )
But, in reality…
… the most important is what players will see 90% of the time.
Variation
One advantage of working with kits → Styles
If all kits follow same logic, you can change one for another.
Then you suddenly have visual level variety for free.
The way they solved doors and frames was with the concept of:
Sockets & Plugs
If the hole shape/size matches, you can put whatever plug you want in that hole.
To handle destruction they opted to have multiple variants.
That way you can have multiple destruction pieces in the same room and they won’t feel the same.
At the same time, destruction can lead to a completely different kit to create transitions.
Finally, one of the best ways to hide monotony:
Decals and small props
By using them, even if the wall is a repeating texture, it can feel completely custom made.
Recap. A modular kit lives or dies on its footprint, the grid and size every piece snaps to. Stay inside it or pieces overlap. Pick pivots that make placement easy, and spend the effort on the pieces players see 90% of the time, not the hero assets. Once the kits share one logic you can swap styles for variety almost for free, and decals plus small props are what keep a repeated wall from reading as repeated.
What this doesn’t cover. This is the design thinking, not the build. I haven’t gone into how you author these kits in a given engine, set up the snapping, or keep the piece count under control on a real project. That’s the follow-up.
