How can I render a normal map from FumeFX in maya?

General Discussion
#1

Hi,
Have any of you used Fume FX with maya and mental ray to generate normal maps for realtime FX? I’m hoping to get something close to this:

I’m trying to create some normal mapped smoke, and I have not yet been happy with the result. This is the methods I’m trying to use:

I will keep messing with it for a bit, but do any of you know a better method for generating a normal map from a FumeFX fluid simulation in Maya?

Thanks in advance for the help!
BK

#2

Unfortunately, I’ve only ever used external programs like crazy bump and xNormal to take my greyscale sim flipbook and generate a normal map from that. It can work in a pinch, with no extensive steps to put it together.

#3

Check out the discussion about it here: http://realtimevfx.com/t/realtime-vfx-dictionary-project/570/3?u=partikel

Tl;Dr You can get ok results using a lightrig, however the nature of fluids (with regards to light transmission) means you won’t get a very good normal as the fluid doesn’t have a solid surface.

#4

Funny to see my old test video of that smoke still floating around. :grinning:

Most of it was covered in the star citizen explosion thread. While its true its not a correct normal map, it still does a decent job of recreating the lighting conditions from the sim.

Unfortunately, That tutorial from Ben Cloward wont work in this situation because it uses negative lights. I posted a different tutorial in that other thread. Its the same method i used in that video.

1 Like
#5

Hmm… We have developed a pretty solid method for generating the normal maps using the RG light rig method… It actually works exceptionally well.

We render 2 RG passes (a positive and negative one) then average them together and rebuild the blue channel based on those two images. I will post some samples later, don’t have any on me right now.

#6

Yeah I’ve done the same, but I think the results are often ok at best due to rhe issues mentioned.
Edit: No longer on the phone so, further explained:

Not necessarily saying that’s due to the normal map generation technique. I tend to think normalmapped particles in general offer very little lightingwise over non normalmapped. It is facing the camera after all so it will never do that much. Also, smoke would probably be better suited by tesselation since the “normaldifferences” usually represents a much larger change than a bolt or a rivet, for which normalmaps work great.

I just think it looks unnatural. If you are going to do light rigs, go whole hog and use the gnomonlight setup Anders Egleus presented at Siggraph. It looks a lot cooler than normalmaps.

1 Like
#7

Is there any kind of vault we could find that Siggraph presentation? Or was that a one-and-done/tickets only kind of thing?

#8

I don’t know if Siggraph has it somewhere. Otherwise, get @Kopp or someone to poke Anders about it. He said he was going to chuck it online :slight_smile: Or is mr Egleus on the forum already?

#9

Thank you for all the help! I’ve managed to get some halfway decent lighting using the light rig normal map method, but I’m still not entirely satisfied. (I’ve also been distracted with other projects…) I’d love to see the Siggraph presentation you mentioned!

#10

Hey, Partikel,
It looks like I’m not able to send a message to @Kopp. Maybe I’m too new to the forum? Would you mind sending him a message, and if you hear anything, posting it here?

Thank you!
BK

#11

Just tagging him will alert him. Be patient :slight_smile: