In this technical article
, Sony Online's Thornblad explains and makes available his 3DS Max content management system, light mapper, and polygon unwrapper, originally created for MMO PlanetSide
already had a basic engine in place with several working components by the time Thornblad started working on it, the engine still needed a component for handling building structures and interiors.
"The original intention for construction of building interiors was to use QRadiant, a popular level building tool of the time, because there were a couple of level design enthusiasts on the project who were familiar with the program.
The problem was that the output was a rather messy collection of triangles in a hierarchically arranged format called a BSP tree. BSP (binary space partitioning) trees were useful for interior level-based games such as Doom and Quake because they represented all of the environmental geometric data and were suitable for the graphics hardware available at the time when those games came out.
In a massively multiplayer game, however, the interior levels needed to be seamlessly connected to a larger world represented by a different set of data. Since the BSP tree data was useless, it would need to be converted into geometry.
But because the process that generates the tree splits polygons, the resulting triangle count would be much higher than was needed to represent the model and thus be very inefficient. As an R&D test, I was asked to reconstruct a model in 3d Studio Max that was originally built in QRadiant."
Creating the model was a simple enough task, but the main challenge was creating the light maps, or textures representing the static lighting in the scene.
Though this was the most common way to represent interior lighting back then, level design tools generated the maps internally using placed lights, and Thornblad needed to be able to create them in 3ds Max. He decided to use a 3ds Max plug-in called Luminaire:
"Luminaire was a radiosity-lighting plug-in designed primarily for architects who wanted something closer to real world lighting than what was available in native Max, but it also had a feature for rendering light maps that proved very useful. The mapping coordinates used for generating light maps are normally unwrapped automatically inside the level building tool, but they had to be created by hand for the R&D test.
Lighting was done inside 3ds Max using standard omni and spot lights, then rendered via Luminaire into texture maps similar to the ones that had been produced for the original model in QRadiant.
The result of the test was a model of a building that looked as good as or better than the one produced in the level design tool, but using approximately one-tenth of the number of triangles. The caveat was that the process took considerably longer than creating levels in QRadiant and needed to be made a lot more efficient or it couldn't be used in full production."
You can read the full technical feature
, which also includes details and downloadable libraries for PlanetSide
's automated unwrap, snap-together interiors, and more (no registration required, please feel free to link to this feature from external websites).