Tim Sweeney Interview -- Level Design, technology and more!

Oh, I probably will some time in the future. I just ain't too interested enough right now to spend the time forming carefully worded questions to Tim.

At some point in time, someone will eventually ask a question, and get an answer, from Tim or John (or some other "famous" developer) and that answer will be posted in an interview/public forum, questions+ answers that may tell us certain minute little details/things about how upcoming hardware may be shaped. You need to ask the right questions, though, and word them really carefully (so as not to raise any suspicion). These kind of stuff usually are already P&C between Tim/John/whoever and a IHVDevRel but things may slip out, right?

I know, coz it's happened to me (although regrettably I haven't posted these tid-bits).

 

Rev, your posts have been arrogant and condescending... if you're not interested, then shut the hell up and read somewhere else. Others of us did find the responses an interesting, if not earth-shattering read.

 

Hey can you guys quit with the fighting . If you guys don't like how the other is responding then stop responding . There is no reasson to start telling others to shut up in a thread as it stops the thread dead in its tracks

 

There's a fine line between being arrogant and offerring frank, if negative, opinions. I did say that I had risked being read as impolite.

I'll take your advice though and henceforth will stfu if I have nothing good to say about anything. That's the way it should be anyway, this being a friendly forum.

 

I like interviews in general and glad Tim decided to give some answers to the questions pose. Now what is BSP geometry? Anyone knows or could explain?

 

i disagree, unless your insulting another forum member, any negative opinions on a product, regardless of how harsh they may be deserve to be here(or any forum) just as much as positive ones.

 

As long as it's relevant and meaningful to the discussion at hand. . .

 

any comment about a product is relevent, just because it goes against the popular opinion doesnt make it irrelevent, nor does it make it trolling.

 

BSP stands for Binary Space Partitioning. It's(was?) used for occlusion culling and collision detection(at least in so far as you could check if you where in solid space or empty space and throw out objects you could not potentially collide with).

Current usage may well be very different, but back in quake 1 it was used to find the "zone" the player is in by checking what side of a bunch of planes the player is(these planes divide space in two, hence Binary and Space Partitioning). You can then attach a Potentially Visible Set to each leaf in the BSP tree(where each fork in the tree represents different sides of a plane, and each leaf(elements with no branches attached to them) represents one of these "zones", hence the name leaf was given to these zones). When we have determined the leaf the player is in we just draw whatever is in the PVS. The PVS was precomputed when the mapper compiled their map(by qvis.exe).

Leafs aren't ambigous because dividing space with planes gives a set of convex volumes. (a volume such that a line passing through the volume will only ever intersect the surface at 2 points). This is also the reason for using convex "brushes" in quake in the CSG.

Hopefully that was technically accurate.

 

BSP was used for virtually all level geometry in older shooters, such as the Quake series, Unreal, Unreal Tournament, and most games based on those engines. It was used because it provided a relatively efficient depth sorting mechanism, useful for eliminating overdraw and necessary for translucent surfaces. The problem is that it is extremely heavily CPU bound and therefore unsuitable for particularily dense geometry.

I never said otherwise.

 

I'd disagree. Being that anyone that knows anything about a product isn't generally allowed it discuss it until all is published, popular opinion is just that, opinion. Popular opinion or not, it's almost all speculative nonsense.

 

Nah, you won't be able to resist It will happen....

 

Thanks soylent and Ostsol for the answers on BSP, sounds like a dual core processor could aleviate cpu usage in the end. Older games but not newer games and now it will be used again, hmmmm.

 

I think that the cost in terms of performance would still outweigh the benefits. The only circumstances where I think it would remain useful for actual rendered objects is when depth sorting on a per-polygon basis is needed. Even then, there might be a better solution.

 

http://www.ga-forum.com/showthread.php?t=59672

 

The world dominance!! Geeeee

And on the other side you have “one-man-showâ€￾ that is doing same what U3 is capable (I’m thinking on Sam McGrath), and a duo Carmack-Duffy that will for sure be beyond U3this time next year with complete engine… Then again times are coming when you’ll definitely need more brain power to keep up the pace with hardware progress, and still be capable to deliver in 3-4 years period new breakthrough in 3D engine! So it, when you draw the line Epic is doing right thing, but still I find it a bit to megalomaniac in a way… It is funny that U4 article end with description of offices and bathrooms

http://www.4gamer.net/news/image/2004.09/20040926054110_30big.jpg

http://img240.imageshack.us/img240/2594/samuelut5xl.jpg

 

Its just an opinion, which is what these forums are about. I don't have a problem with Rev's post even if his glass is half empty instead of half full.

 

Nah, it'd be more interesting to make use of multi-core processors for other tasks. Basically, BSP is only an overall peformance win (for graphics...there may be applications physics processing, I don't know) for software rendering. Good depth sorting and visibility culling just isn't that important with today's hardware renderers.