Any VR VFX Insights?

vr
vfx

#1

My vfx experience with vr is limited to rigid bodies at this point. Have any of you worked with weapon/general effects involving smoke/explosions in vr? What were definite do’s and don’ts compared to traditional game vfx? I hear there are concerns with double overdraw and camera facing sprites break down pretty quickly.


#2

May I suggest to use the search function, its great to see if there has been a discussion in the past about something you are interested in.

that being said, any new info is always welcome :slight_smile:
/me stares at fellow rtvfx-ers :slight_smile:


#3

Thanks for the suggestion and the link; I’m well aware of the practicality of search function. I tried a dozen searches and not a single one showed that thread. I will have to evaluate what I did wrong. Anyhow, I also look forward to any new insights and hope to share my own. I’m working on a commercial project with a tight deadline so I’m hoping I don’t have to change my pipeline too terribly much.


#4

Also, I’m an idiot. I wasn’t searching tags. Still, I’m surprised there isn’t more discussion about vr. It seems like every-other client is developing for vr these days and their expectations are ever higher.


#5

Yes, but most are not big enough to warrant a dedicated VFX artist so most of them just go with assetpacks and traditional techniques.

There are quite a few engine specific things to consider as well which complicates the discussion. In Unity, out of the box you can’t use any pivot offsets or it’ll freak out in VR while Unreal has functionality built in to compensate. Everyone who’s developing for VR is finding the way as they go, a bit like general RTVFX did say 5 - 10 years ago.

General advice:
Use meshes where possible.
Compensate for Roll.
When close, don’t use high alpha sprites.
Small particles hanging in the air always feel cool due to parallax.
If possible, compensate for both cameras with sprites made for it.
For performance: WWTPS2D (What Would The PlayStation 2 Do) with this effect.


#6

Materials that have controls tied to Distance to Camera,
masked opaque particles where you can,
in Unreal remember to turn off the roll for VR, or things will wiggle with every wiggle of the headset.


#7

Alright, thanks for the input. I suppose the general body of knowledge on this subject is relatively small at this point and it’s good to know there are more unsolved problems with vr than I assumed. The don’ts are very clear to me now and these creative solutions are a great starting place.


#8

I just did some weaponFX in unity for VR (Halo Recruit project). Definitely don’t use single cards. Use at least 2-3 with slight offsets to give a volumetric feel.

@Partikel You mention compensate for roll. I’m a bit new to Unity, so I haven’t solved that yet, but it’s a question that keeps coming up. Know of any threads on this or have any advice? A cursory search of this site and on google didn’t come up with anything.


#9

Don’t use the billboard render mode if you can avoid it. Vertical/horizontal billboards don roll and work in many cases.

However if you need billboard on things that are not round, you might need to get some code support along these lines: https://forums.oculusvr.com/developer/discussion/5998/hmd-roll-and-particles


#10

It would use tons of overdraw because of it’s amazing fillrate? Haha :stuck_out_tongue_winking_eye:


#11

We had some insights from a Game FX Artist recently, you may wish to access the video: https://goo.gl/9G4w7S