Fluid Effects vs Fume FX

#601

Yeah finally we can do some decent testing with auto size grid on. The only reason why I have practically stopped testing fluids is because it takes so long to sim.

#602

i have turned texturing off but it it looks the same, i assumed that since there are fluid artifacts (dots) in the viewport that it wasnt a shading/texturing problem.

#603

Did you cache it with texturing on? You may need to delete the cache if you did.

#604

over sampling your cache can help alot, but it will change the results of your sim quite a bit.

I always try and figure out how much oversampling I will need while my sim is at a very low resolution, then go to work on it.

#605

I think it lacks some detail to get more realism.
What’s your resolution?
Good work
Cheers

#606

Im having a bit of a problem with the overall look however. Its very noisey.

I’m not sure, but it could be that the thresholding of the opacity graph combined with the high incandescence is making the density a thin bright shell which is hard to sample. If this is the case then increasing your fluid shading quality attribute will improve the look( although take longer to render). Smoothing the opacity graph to avoid the hard cliff on the left side would also help and not require the increased quality.

Duncan

#607

@ jedipottsy
just to second duncan`s tip,
can u reduce ur temp turbulence to 2 or something lower? in fire u dont need to have much temp turbulence or else it will behave more like explosive & have a little more diffusion in temperature so that it allows heat to propagte in neighbouring voxels.
using texture with fire is totally fine as I believe it add more details like fume into it but make sure the co-ordinate speed is set to grid.
I see u are not using high detail solve On which is good I believe coz fire normally doesnt need to have High detail solve ON. i normally keep it off for fire, but for smoke it can very helpful though!
hope it should solve ur problem.

#608

I think having the vertical swirl to 0.3 caused the blotches. Changing that the sim is smooth with quality of 1, but now the simulation looks different. I adjusted the shading slightly aswell.

I have a resolution of 143x195x156, which is probably the most my computer can handle, but im not getting the detail i would like. How would i achieve this?

Thanks for your help

#609

geez man I thought that screen shot was one of your renders! nevermind it is hard to get that kind of detail with Maya ATM, Im thinking 2011 is gunna be a breakthrough though.
To help with breaking up the fluid a good method is to use 2-3 volume emitters at different sizes with low but varying emission turbulence. Also the opacity graph is important to get that right with most of the flame transparent with maybe one or 2 spikes in the graph. Thats my method that gives nice results. Vikas likes to include a texture in there as well but I would do that last just to give it its final touches.

#610

Make sure to use high detail solve. This is critical to getting good detail. Start with no texturing then add it only once you get close with your simulation. Use turbulence on your emitter and make sure the emission is fairly sharply defined. Carefully adjust the turbulence speed and frequency to break up the flame. If you emit a smooth glob of density it will not become sharper over time, only more diffuse. Don’t use any diffusion, even on the temperature grid.

The opacity and incandescence ramps need to be carefully adjusted. I find that it helps to have a sharp transition from bright orange-red down to a mid range red to mark the edge of a flame. This is useful for creating that licking flame effect, while still having some smoke.

When you do add texture, adjust the frequency so it is a bit elongated vertically and animate the y offset of noise to move upward, but not quite as fast as the flame. Also animate the texture time… the speed of animation is important for the right effect.

Duncan

#611 
  Gee Aikiman have a little faith in Maya....hehe.
  
    
  Jedipossty,
   
 Don't be discouraged, Maya can create great fire. Duncan's tips are awesome they should help you alot. Just to add, try to narrow some things down. For example, no need to adjust your vertical swirl settings. And I think your res is actually too high. With fire I noticed too much res actually hurts the look of the flame. Vik is correct about temp turb. That's gonna kill your flames. Density or emitter turb will do the job. You are on the right track. I'm sure you will nail your next test.
#612

I turned off diffusion and i got nice results but alot more noise. After re-creating the container i found the noise was coming from the firewood mesh, reduced poly count and got rid of the twigs, almost no noise now. Thanks for you advice Wayne, Duncan, Vikas and Aikiman.
Much closer to the campfire i was thinking of, need to add a bit more detail and change the opacity ramp. Container size 88x105x96. It also simulates much quicker now.

http://www.youtube.com/watch?v=OsYz_uQ01z0

#613

Visor has always been a gr8 resource for me & I most of the time use it a lot as a good starting point for me to do any fluid effects.

I have learned a lot from you Duncan & from this thread too. thanks much for all but with all due respect Duncan…nothing personal just wanna know why most of the 3d flame example in Visor has temp diffuse on. they all are set to 0.100.
In most cases I dont use this high value on temp diffuse but I use a small number like 0.020 or 0.040.
It helps me to soften the edges in bright areas on fire & explosion tests.

from an enthusiast to my present carrier I have hardly seen anyone using High detail solve ON for simulating fire.even the native fluid guys at work have created amazing fire/fireplace effects with high detail solve OFF.
may be I can do some test with high detail solve ON vs OFF for fire & I might get my answer.
i`ll post about my findings soon.
Vik

#614

I made a campfire last night:
vimeo link

Res is 120x180x130, high detail solve is on, no velocity swirl, nine emitters with turb cranked, no diffusion in temperature or density and a sharp falloff on the opacity graph.

I would like to add particle embers and try a higher res sim to see at what level the detail balances out to the best ratio of speed/quality.
-shawn

#615

Wow i really like your shading, how did you get it to look like that? I tried rendering with high detail and low detail and this is the difference
http://www.youtube.com/watch?v=Eh1YNFU1wiQ

I added a little temperature diffusion (0.030) and it made it look a bit smoother. I have swirl to 10, though ill try it without velocity swirl.

#616

Great fire Shawn.

#617

Hey Shawn u made James Bond Night-fire …Want to see more cool fire.Best of Luck

#618

Hey guys, heres an updated, added more turbulence and tweaked the shading. Reduced velocity swirl to 3 from 10.

http://www.youtube.com/watch?v=Ma_Q3L3g95Q

#619

haha great fire shaun, but no scene file this time?! :wink:

man, youre racking up alot of cool lil demo scenes for everyone, rock on!

jedi, looking alot better, just a lil too uniform still…

#620

It’s not done! I want to take the scene into 2011 first. :slight_smile: