Breakable environments discussion (56k warning)

Jonathan

So I figured it'd be good to discuss breakable environments. First here are some examples, some are procedural breakable objects, some are purely replacing unbroken objects with cut up meshes, and some are a mixture, it seems.

Gears of War 2 tech demo/Unreal Engine 3 improvements
(procedural mixed with various art assets?)


Stranglehold (UE3 game)
(from some tests, it appears the unbroken objects get replaced with pre-cut objects on the fly, like many other games, there's just a whole lot more in this game!)


Messing around in CryEngine 2 (Sandbox 2)
(the glass is 2D/procedural, and cannot be too curved)

(Mixture of procedural, and a premade "broken" piece being added to the new end of the tree)

Here's the SDK documentation on breakable objects in CE2, BTW,
http://doc.crymod.com/AssetCreation/frames.html?frmname=topic&frmfile=index.html

So how do you think this will effect your workflow, the more games use this?

What should the artists be aware of when working with such a workflow?

Eric Chadwick

We talked about this a little bit awhile back.

Not much for artists to do here, it's really going to be driven by the tech itself, except to keep the lines of communication open with your programmer buddies at work. They're the ones who will be creating the actual cuts, with their 1337 coding skillz. Well, besides influencing the way things will be rendered, artists can add the ancilliary particle effects and such.

Jonathan

Ah, thanks.

I searched, but only got a Gears of War 2 thread and another thread which didn't discuss it.

Eric Chadwick

It's still interesting though. LucasArts also showed off some breakable tech recently.



[ame]http://www.youtube.com/watch?v=e2G7JRAH9LU[/ame]

Jonathan

Ah yes, the Force Unleashed game, the reason I own a console.

ohnein

I don't know what I can say about the Gears stuff but breakable pieces are artist generated from within the editor (UE3).

Rob Galanakis

Lucas bought Digital Molecular Matter a year or two ago, I think... their stuff really blows away everything except maybe Crysis which it still seems to beat pretty badly (haven't seen the new Gears stuff, though). Props to Lucas Arts for really making good use of DMM, too. The destruction in Force Unleashed seems to be much more important than mere eye-candy/effects.

But as Eric said, there just isn't much for artists to do. And for that you should rejoice.

Lee3dee

ohnein wrote: »

I don't know what I can say about the Gears stuff but breakable pieces are artist generated from within the editor (UE3).

most breakable objects in UE3 games are created by the artists, they usually make the model first, then break it down into individual pieces, and after a lengthy process of making it into a skeletal mesh, they bring it into PHat editor which then allows the mesh to be given physics properties. Then you can place it into the game to be destroyed.

I maybe missing a few steps on the process. I'm experimenting with this in UT3.

ohnein

Epic added a new mesh type specifically for breakable meshes. It doesn't involve phat or skeletal meshes.

Lee3dee

that's probably a feature in the updated engine that ships with gears 2

ohnein

Yes, it is. Hopefully we'll see other licensees use this feature in future games.

gamedev

If the destruction is procedural (I.E. its different every time) then yes its mainly code. My studio has written some custom tools and actors for UE3 to make this process easier for the non-procedural stuff that usually includes breaking up a mesh into interesting pieces and then assembling it in engine again where physics and some kismet are applied to make it break apart realistically when shot or damaged. On average, a breakable or destructible object will 1-2 times longer that building the base object itself. Though it can take longer, you'll generally get better looking (and more performance friendly) results using a non-procedural approach.

You can check some this out in the Bourne Conspiracy demo now on Xbox Live.

-Tyler

Temaruk

I just noticed this:

http://www.mirvadim.com/index.html

"RayFire Tool gives You ability to shoot, destroy, demolish, ruin, break down, make havoc, blow up, burst, detonate, explode and do other similar things..."

Ged

Temaruk wrote: »

I just noticed this:

http://www.mirvadim.com/index.html

"RayFire Tool gives You ability to shoot, destroy, demolish, ruin, break down, make havoc, blow up, burst, detonate, explode and do other similar things..."

I think these guys are chatting about real time 3D breakable environemnts rather than ones which require a dedicated renderer. Though it would be cool to see these tools go into real time engines.

The 2 main third party engines Ive heard of are havok and Physx(used to be ageia now owned by nvidia)
http://www.havok.com/
http://www.nvidia.com/object/nvidia_physx.html

Jonathan

If you have UT3, you can try the Ageia maps. They'll run great for a little while if you have a good machine (like an 8-series or equivalent ATI card, and a dual or quad core).

However, after a few minutes in the match, stuff will start getting broke, and the frames just go way down, often 8-12fps. Supposedly a PPU card helps, but not that much it seems. This is with a Q6600@3ghz.

Also, for UE3, yes, most of it *has* been artist-generated objects, but during Epic's tech demo, Mr. Sweeney discussed it as being purely procedural, unless I'm mistaken (besides modeling the metal that will be inside the concrete, etc.).