Does anybody have any idea how they did the really big explosion in the new Battlefield 4 gameplay trailer?
http://http://www.youtube.com/watch?feature=player_detailpage&v=U8HVQXkeU8U about 9:10 in.
The rest of the pfx work looks like sprite work (really nice sprites but still) but that kind of rolling explosion is so hard to do with sprites. Maybe flowmaps on sprites i guess?
Really wish i had a copy of the Frostbite 2 engine to play with
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They say a few things about it in this video (at around 4:36).
It is some kind of volumetric effect. So it seems like they're raymarching (a basic example of raymarching I've seen: "What does the place I'm at now look like? Move a bit forward. Repeat.") voxel data or some other kind of volumetric data.
http://dl.dropbox.com/u/5913234/Battlefield4_Explosion.gif (15MB)
The problem I see with raymarching , especially if done per pixel would be expensive.
without seeing it closer its hard to tell, other than it looks really nice
Someone (smb02dunnal) recreated the effect in Unity 4 (DX11 mode) for Unity's recent DX11 competition. He posted a zip of the full project, so you could check that out to see how well it performs.
Keep in mind that he made several entries for the competition, and the competition only lasted about 2 months, so it might not be as optimized as the effect you see in the Battlefield 4 trailer.
Consider this game is coming out on Xbox360 and PS3, I wouldn't expect they would have an effect that wouldn't work on these platforms. Unless of course they are desperate to have everything read for the next consoles (well I am sure they are, they were for BF3 but had to scale it back). I'm sure someone from DICE will pop up and let us know
The only problem is, you would then need a pretty dense mesh.
The one of BF4 looks impressive, but if it's coming to consoles too with that effect, then I would say it's just really impressive texture work with some nice flow/vertex offsets that are doing the movement work mostly. I wouldn't be even surprised if for optimization reasons they just used a Stack-Map (Masks in the channels) or so.
What really makes that explosion impressive is the lack of aliasing around the edges and proper sorting of the mutiple layers of the smoke, which is what gives it that nice volume effect, unlike many other explosions which only default to a simple additive and have to fight with alot of optimizations just to make it work, especially for a fast-paces FPS games were rockets fly at you form all directions.
I remember not too long ago LoTtek made such an explosive effect and showed it off for UDK, I can't find the link, but it was pretty cheap and actually looked for something that was whipped out in 5 minutes and lacked real textures.
source: a buddy at dice
Also what software was used to create it.
If its multiple parts I am sure it can be used plenty of places, it seems to have volume.