Speculation on Source, LOD, and low end systems


May 14, 2003
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I was reading another HL site somewhere, and it pointed out that way back in 2000, talking about TF2, Valve discussed their LOD system. Gabe also mentioned the LOD system in the tech demo, and especially noted it when he was explaining how the game could work even on low end systems.

Here are the quotes from 2000:

"As announced earlier, TF2 will use a special licensed model Level of Detail system that lets the developers create and animate one extremely high-polygon model and the game will adjust the polygon count to keep a constant framerate. Up close, the models are incredibly detailed and lifelike. What's interesting about the LOD system used for TF2 is that it doesn't just reduce the polygon count based on distance, but based on the number of characters on-screen as well. Basically, you give the game a target framerate, and it will adjust the polygon level of all models at all times to try to meet it."

"They're doing a network LOD system where, say, the location of an opponent who is far away is always updated, but not necessarily his exact animation frame, since it would be hard to see his body position in the first place. Apparently, they're doing research into a whole new method of networking for Internet games and may give that a try as well."

Even though this info was for TF2, it was still the same engine and tech, and I'm betting this is how they can acheive a playable game even with a low-end computer: basically you tell the engine what framerate you want the game to run at, and it adjusts the LOD settings accordingly to any given situation.

If this is true, then it sounds like the game will tailor itself to look about as good as anything else could on the particular system you have and still be playable. So it's not like it will look like crap compared to the games you play on the system you have now. It will probably look pretty much as good (maybe a little better, maybe a little worse, given that it has more physics and stuff going on) as those you are used to.
Actually HL2 is not the first game to use LOD, i know that they use it in JKII. I am not sure if Vavle thought of it first and others started copying it but it is already been implemented in other games.
Far cry and Stalker are like that, two different engines though but sounds like they will run on moderate systems.
Actually HL2 is not the first game to use LOD

Actually, no one said they were. This is about their particular LOD system, not the first LOD ever. Thanks for playing!
sounds like the same old LOD system other games use to me. And as you said that was for TF2 not HL2. And they are not using the same engine as during the development of this game they scraped the engine like 3 times to create a new one so who knows where Source acutally started its production. And this question just popped in my head, what was the guy's name who was heading up TF2's development, Robin Walker i think? Right? What the hell happened to that guy.
Sorry bout this, someone had to ask.

What is LOD?
it's going to work basically how you said.. but there are other things then poly counts that effect how well a game can run on your system.. just the environment and lighting could make the game suffer on desktops which have slower less advanced video cards.. like the geforce 2 (which i have. :dozey: ) ... but yeah.. hopefully the LOD used in hl2 is the perfect balance of improving game performance on slower systems and trying not to be extremely obvious like in some games which exist today.
Yeah and sound, has anyone played BF1942, my god the sound in that game eats everything, you turn off sound and the game runs smoother than a baby's ass. And LOD stands for Level of Detail
Originally posted by Dr.Sbaitso
Yeah and sound, has anyone played BF1942, my god the sound in that game eats everything, you turn off sound and the game runs smoother than a baby's ass. And LOD stands for Level of Detail
true.. bf1942 could barely run before i messed with the sound settings...

though LOD does stand for Level Of Detail... the anagram LOD is meant to be the system in place to SCALE the Level Of Detail to improve performance and although the definition or assumed definition is more complicated the people always just talking about the level of detail in the game it is usually just represented by the letters LOD.
Their LOD targets a certain framerate rather than just being a standard distance setting. They also do LOD based on the number of models in the scene (which is new) as well as doing it for animation frames sent over multiplayer. All of this is fairly new to LOD systems.
LOD = Level of detail.
Uhhh...third time's a charm?

Well...then...that last post of yours is incorrect! I'm reporting you for reporting fradulent information....uhhhh...yeah...I'm running out of 'funny' here. A thousand apologies.

Even if the polygon count scales to boost framerates, there are still a lot of cool effects that you're going to miss out on if you lack the Pixel and Vertex shaders of a DirectX 8+ graphics card. The guy says during the tech demo "The graphics of the Source engine are based around shaders".

As far as I know Robin Walker is still working on TF2, but Valve never seems to update their web page. I went to the same high school he did, his mum teaches Art there. Some friends of mine were considering kidnaping her and not releasing her until Robin sent us Half-Life 2, but decided it wouldn't work. "Half-Life 2 for my mother? I'll keep Half-Life 2 thanks". ;)
LOD stands for 'level of detail'

oh wait someone already said that. It's ok keep cool, keep cool. Actually that's wrong. Yeah. LOD stands for Local Orthodontist Directory

on an academic note, i belive messiah featured the first LOD engine.