Team Fortress 2 started adding community items a while back, and more recently introduced the Mann Co. Store, opening a flood of new items made by avid fans of the game. However, these fan-made items, and even some of Valve’s own-made stuff, have a bit of an optimization issue. This has gotten a few members of the TF2 community in a stir, and one user in particular has brought some excellent tidbits to light.
To get people up to speed on the matter, let’s talk a bit of game design. The models in Source Engine games are able to have what is called “Level of Detail” or LOD for short. This technique means that the further away a model is the lower in detail it is. Usually, models sport around 3 or more of these models at varying quality, a reduced poly count and lower quality textures to high quality, high poly models when up close and personal . This means rather than rendering out a character who is a hundred yards away at full detail with thousands of polys when they’re only going to look like a red blob to you, it is rendered as a model that is just a red blob.
All the models that came out with the game back in 2007 have several LOD models each. But of the models added since release, including ones made by Valve, only a handful have LOD models available. Meaning players kitted out in the latest Mann Co. gear is likely accounting for tens of thousands of polygons despite being on the other side of the map. This in turn means the rendering of models is more intensive than it needs to be.
Here’s a nice break down done by Steam user Ravidge:
A player using the new gear is at a distance requiring the rendering of ten times more polys than their vanilla player counterpart. That’s a pretty unacceptable, even more so when things like the hats work out 4 times more polys than the entire character model.
Now Team Fortress 2 is certainly not anywhere near Crysis in terms of computer crushing resource demands, but it is a game that has gained somewhat of a reputation of running on relatively low-end machines. However, the increase in badly optimized community models does throw that in jeopardy. The TF2 team have taken note and, in response to a player email, Robin Walker has said coming updates will start to deal with the lack of LOD models. I just think it’s something that should have maybe been in place before they started accepting community made items. Especially when some of them have quite a bit more detail than the vanilla set.
For those who are interested, Ravidge has also made a mod for TF2 that strips out hats from the game, both helping with rendering and also for people who have developed a hatred for hats. Which can lead to interesting results.