In this
in-depth technical article, Neversoft co-founder Mick West examines how procedural generated content and compression can lead to expanding vistas for your open-world games.
Open-world game environments and objects are typically spooled from the disc as players move through an area, with scene complexity often determined by the data transfer rate of spooling and the virtual speed of the player within the world.
If a world has too much complexity, then new glitches may result when data cannot be spooled fast enough as players move from one region to another. To prevent these problems, developers can restrict players' maximum speed so there is sufficient time for the world to load, and they can place limits on scene complexity and allowable variation between regions.
To allow for more complex environments, West suggest that developers take advantage of procedural content -- content generated from mathematical descriptions of underlying forms and parameters describing the specific instance of that content -- and procedural compression:
"Procedural compression is simply storing a piece of geometry as a set of procedural parameters rather than as the final model. While this is not compression in the normal sense of the word, the effects are essentially the same, only with a vastly increased (even arbitrarily large) compression ratio.
The disc spooling bandwidth requirements are thus greatly reduced, allowing us to pack vastly more level geometry into a small percentage of that bandwidth. The trade-off is that artists have reduced flexibility in the models they can represent, since they are constrained to the possible output of the procedural algorithms.
We also trade some CPU resources, since the generation of geometry may require more CPU time than the standard spooling and decompressing of the raw data."
You can
read the full technical article, which includes more information on procedural compression and solutions to the resource problems that come with the technique (no registration required, please feel free to link to this feature from other websites).
