speedrun questions

[volumetricsteve]

I've seen a handful of Quake 2 speedruns over the years...and a few of them make use of tricks that seem to break the game rather than swiftly move through it.  There are some things I get, like doing things out of order or skipping entire sections by being clever, but there's one move in particular that I can't make any sense of.
If you see here:

www.youtube.com/watch?v=e6iQVqCi8hM#t=645

The player manages to jump on the reactor core before the metal part lifts up, somehow rocket jumps off that and goes sideways, then for some reason the wall to the next section just explodes.  I've googled around and I can't find anything that explains what's going on here or why this works, I've noclip'd around that area and I don't see anything that looks exploitable in quite that way, but I've seen a few speedrunners do that trick and I'm at a loss.

Any ideas on what's going on there?

[knightmare]

Looks like they either hit a trigger (which are invisible) on the wall by the door on the far platform that triggered the door to explode (note the Big Gun access denied message), or they somehow destroyed the reactor core func_explosive with that rocket jump. It's either caused by a trigger or a radius damage clipping issue.

[volumetricsteve]

That has to be it, I wondered if that was true..I also watched a speedrun of portal where they very clearly exploit a serious bug in the game and manage to somehow clip outside of the playable world allowing them to skip tons of game time. I thought this quake 2 trick might be on the same order of "bug" but in this case it seems like the engine is actually doing what it's supposed to. Also, I just tried KMQuake 2 for the first time yesterday, really good stuff!

[knightmare]

I'm glad you're enjoying KMQ2, I've put a lot of effort into it over the years. I'll have a new build with HTTP downloading and PNG texture and screenshot support out soon.

[redangel121]

KM is right. there is a trigger above the door that lowers when certain other things happen. the guy in this video explains it as he does his speedrun www.youtube.com/watch?v=zj-jKn_e0k0=1110

[knightmare]

It looks like the level designer used a trigger_once in an out-of-the-way spot by the ceiling as a single-use relay, instead of a trigger_relay, which can be used multiple times. This is sub-optimal, as the trigger brush uses up one of vanilla Q2's 255 model slots.