HL2 has clipping problems



I just watched the HL2 video from E3 again and I saw something that made me sad :(.
In the first fight scene in the prison, I think its like 14 minutes into the vid, you can clearly see an ant lion attacking a soldier through a mattress that is set up as a wall. And its not just a little bit of him either its half the body. This made me sad cause everything else in HL2 just made me gasp in amazement.
I thought that weapons sticking through doors and bodies lying through walls was a thing of the past but maybe its not...
Yes weve talked about this a few times in the past. We mostly concluded that it was probably something that Valve will have fixed when HL2 is released.
it is a thing of the past..walls need to be made a certain thickness though..

I think a mattress can be torn apart by a ant lion im sure of:dozey:

But seriously, it's been discussed alot.
Derrrr...serch? Wot iz dat?
1 4|\/| 1337?
ghess nought.


We have three overturned matresses in the scene, enemies behind each, and bugs attacking them. The very first matress appears, to one of the bugs at least, intangible. For the other two matresses, however, the bugs go around to come in from the sides.


Three possible things that could be going wrong here.

1. Something about the bug "Attack" animation allows it to push through objects, getting it stuck inside them.

2. This one matress is, for some reason, intangible, while the other two are fine.

3. The game just hasn't got clipping all worked out yet for the physics model.

All three options are "bugs" except maybe the last. The last is interesting, because at least in most modern game engines, there is a tradeoff between clipping and things getting stuck. In the real world of real physics, we're able to move any part of our body as needed to nevigate an area, and if we're walking along, and pass a chair to our left, we can just pull in our left arm so as not to graze or bump it. But in the game world, even the tiniest object sticking out can block an entire character's movement. Indeed, even a tiny crack in the floor can trap a character permantmently, because their animation to get into it was playing at just the right moment, and they can't play it backwards to get out the same way, the way we backtrack exactly as needed in real life.

The solution, in game world, is to make clipping a little more forigiving around a character's bounding box. This gives rise to visual oddness at times, but prevents things from getting stuck: which is generally a MUCH worse problem (since it makes the game far less playable, while clipping only looks odd).

So maybe this is a bug, or maybe it's just an artifact that's necessary to allow things to move that occasionally allows characters in the right situations to clip foolishly.

My bet is that it's just a weird bug that they can iron out. We'll see.
Damn i hope they sort it out. If they dont its not totally next generation, is it?

(well, imo).
i've taken a screen shoot of the part i was talking about.


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thats nothing... If you wanna see clipping problems watch the scene where gordon throws a nade under the blue trash container which slides down on top of the soldiers. Gordon then jumps down onto the blue trash container and from there onto the floor. He then turns left to look into the container briefly and you can then see part of a soldier sticking up through the side of the container (which has now become the floor so to speak) even though he should be a flat pankcake underneath it!!!
I don't think HL2 has the ability to flatten people like that. It's either clip through beams like that or splatter them. Splatter probbly would have looked better in this case but I think splatter was either turned off, will not be HL2, or wasn't in yet because when gordon nades the first 2 combine soldiers in the barney clip they also probbly should have splattered. The guy who falls at the end also probbly should have instead of bounceing.

Perhaps there are no splatters...I think it works a lot better, at least when those two combine come flying at you in the street fight...it looks much better like that than what it would've looked like if they just gibbed...

Yeah, me too, but I don't think it would look really appropriate in the ultra-realistic world that is Half-Life 2.

Ya the grenade did look cool and I'm probbly with you on wanting no splatters thing just to see stuff like that even if we had to put up with some clipping problems. But I think the dumpster and the fall should probbly have gibbed. I mean one ended with some bad clipping and the other the guy just bounced when he hit the ground. Perhaps you should only gib if you are going to create a clipping problem. I'de go with that.

Gibbing isn't very realistic, though severable body parts would be in big explosions. The grenade in the barney video I have mixed feelings about. First of all, that type of grenade wouldn't necessarily gib, and most grenades work on shrapnel, not pure explosive power. But the body was flung so far, with so much force, that the initial explosion must have been VERY powerful: perhaps powerful enough to due some major, major damage.

But I'm happy even if it doesn't. While it would be nice to have some sort of "pain" skin that shows major damage, or to have severable body parts (a la the zombies and the rotorblade), the ragdoll deaths are still pretty darn neat, and my major wish is not gibbing but rather some death animations that are more subtly worked into the ragdollness (such as waving arms while in the air, or clutching the air as they die, or shuddering, etc).

I agree that the body under the crate should have gibbed... but that's pretty hard to work out. I mean, the body under the beam would have looked silly if it had gibbed: so how can you do both? I'd much rather have had the crate actually lie on top of the body instead of clipping throug it. Even something that heavy wouldn't necessarily completely squash a body.
well the clipping in the vid could have to do with the fact that the levels arent tested to 100 % so one matress has clipping problems and another one doesnt. Its only the first matress that the ant lions can attack through.

As far as the dumpster scen they could have just made the part of the body that is covered by the dumpster to disapear and it would give the same effect as splattering without the whole body being splattered. I dont know if its possible to do this but if it is then valve will probably fix the splattering part in the full game, or find another way to do it.

Remember that HL2 isnt going for the gore effects of SOF so i prefer the bodies flying than just falling down. Its cooler this way, its makes a wow effect
by the way.... matressess are not bulletproof!!
The following picture shows one of the wood pieces after the big antlion crushed through the wooden ... wall (?), anyway, half of the piece is below the floor, and if you look at it in the video it rotates wich makes it look very wierd..
Just wanted to comment that :E

Gabe Newell have said that those clipping problems will be fixed, so just sitt back and relax. :)
Oh, I found another clip, and in the same scene ^_^

And guess what else I found? Look at the zombies when Gordon blows that car into them... yes they're definitely gibbing :):)

[EDIT] - Watch it slow mo, the explosions pretty cool too :D
Originally posted by |MaTT|
by the way.... matressess are not bulletproof!!

They arent bulletproof but u still cant push half of your body through them and then come back out without making a hole, try and you'll see.:cheese:

I hope you're right zerox and thats its only bad programing.:cheers:
By the way where did you here that its gonna be fixed
You must realize that many of these clipping/collision problems are results of deliberate decisions the programmers have made for various reasons (mainly optimizations) whilst knowing that these decisions could (and would) result in errors such as these.

Collision detection and physics may be tweaked to eliminate some of the clipping error occurances and/or make the problems less obvious but I can more or less promise that Half-Life 2 will not be entirely free of clipping errors.
Originally posted by baldrik
They arent bulletproof but u still cant push half of your body through them and then come back out without making a hole, try and you'll see.:cheese:

I hope you're right zerox and thats its only bad programing.:cheers:
By the way where did you here that its gonna be fixed

Another one expecting too much from the engine! :naughty:
no im not expecting to much, only the best game in the world.:cheese:

but seriously, in halo for example I never saw a single clipping problem and i blew guys all over the place with grenades.
But even if HL2 has clipping im still gonna love it. It has already made me look at games differently when I see new previews. I start saying to myself "well it doesnt look as cool as HL2", but thats maybe just me.
Lets us be honest with each other for a moment: I'll live with it and so will you.

Firstly, IMO, its a relief to see somthing to remind me that this is still a game. Its getting so difficult to tell the difference between reality and non-reality these days (at least since the accident).

Secondly, even if they don't fix it by September would you rather, in August, Valve goes:

"Sorry guys, but we've had a chat, and decided to recode the collision algorithms to make them accomodate some minor unneccesary things LIKE WHEN A CAN INTERACTS WITH A BOTTLE! What was that? September? Ho ho ho! Good one! Try January".
First of all, I already saw gibbing, in the flaming zombies part, when the car blows left, it squashes a zombie, and it gibs.

Second, I'm sure they'll fix it, and even if they don't, Valve could just release a patch or something if it's so important.
ARGH! I already said that, why must people ignore my posts :flame:
Yeah but so did I, ages ago.
and probably someone before me.

not much you can do about it...
Oh no, the world is coming to an end!

In all honesty, if it stays in the game I will not care at all.
I'll buy the game even if they havent fixed the clipping problem, but it would be nice if they did, I like the game bekause you get to use more realistik ways to kill stuff than in hl1 where the only way was to kill em all!!:devil: but there the story was wery interesting...(wich i hope there will be in hl2)
and I totaly loved to kick the last bosses as!!(wich i did repetingly :evil: )
Originally posted by baldrik
By the way where did you here that its gonna be fixed

Hmmm, can't find the source but when i do i'll say it here.
Yeah I agree. Its still gonna be a great game but it kinda ruins all the work they've put in to make it really realistic
Something I noticed in the 25 min video, when the flying manatee (think its called a hunter) is chasing you in the buggy and gordon picks up the rocket launcher. The thingy shoots at gordon and hits the apc, even though gordon is hiding practically under it, you can see sparks when bullets hit the apc, even though they are hitting the other end. I don't know much bout computing and technical stuff, but why would that happen?
That's just a rendering error. Gabe said its on the list of issues to be fixed.
the clipping isn't a rendering problem, it's an engine problem.