Hi tokanohanna,
just wanna say that your example is really awesome dude! Im having trouble trying to recreate it myself which probably isnt helped that I have a slow system. Just a question if I may…how did you do the secondary smoke on the ground, is this a second emitter?
Also the light setup, using real lights really flattens the look of the fluid quite a bit, are you using raytrace shadows? Cause that really kills the render times!
Hey Jeremy,
Thanks for the feedback. Regarding the secondary smoke on the ground, it is actually being controlled by an volume axis emitter. I just have 1 emitter in my container. Keying the buoyancy “on” when you key the axis field “off” can create this effect. It’s quite difficult to have more than 1 emitter due to them both sharing the fluid container properties. You can use an additional container just for your ground plume, it just takes longer to set up. Also, cache it before you render both containers. You don’t need to cache your main container since your res might be too high. Maya does not do too well trying to render 2 high res fluid containers at the same time. I have a sim I did a while ago with two containers. I’ll post the sim when I get a chance. You should also play with the “Over Samples” settings within the Solvers drop down menu as well. This allows your fluids to render well together, if you are using 2 containers. Raising oversamples will slow down playback but it makes the sim quite stable. If your system can’t handle two containers, then render them out in different passes.
Using real lights is optional depending on your shot. If your comp has real lighting in it, you may need to turn on “real lights”. If the smoke seems flat, turn off "Enable default light and turn raytrace shadows on. Chuck a few more lights in the scene to create more shadowing for the fluids. I get good results with a 3 point light rig with raytrace shadows. Maya 2009 does a much better job of raytracing fluids than earlier versions. To help with render times, you can cheat a bit by keeping the quality at 1 under the Shading Quality tab. Under the anti-aliasing, in the globals tab, 0 and 2 does just fine. Guass for the filtering. Box speeds up renders as well. You can have your quality set to 2, but it literally doubles render time. You’ll notice there really isn’t a difference between the two. By the way, great site dude, your tuts are very helpful.
@Jeremy: This is the shot that I lower my temp turbulent down. Somehow, the keyframe of temp buoyancy doesn’t work at last. But the smoke is so smooth when I low the temp turbulent down. I’m not sure how I can get the random movement like tokanohanna’s.
@tokanohanna: Thanks for your suggestion. I’m making a new one right now and the playblast looks so good. I’m gonna upload the new vid with your suggestion when it’s done rendering. Before that, I have 2 questions. When I lower my resolution, the sim is totally different compare to the highres one; although, I didn’t change any settings. So the resolution doesn’t relate to the quality at all, does it? Another one is that, what is the best value for texture time and texture origin? Did my expression set them too high for my scene?
Just finished the rendering. This is the shot that I made base on your suggestion. It doesn’t look as good as yours but I will keep working on it to understand how fluid works. The texture seems to move really quickly although my expression is really low 
Accordingly to these more container and more äh more emitter setup, does anyone
tried to have seperate emitter for Heat and Fuel/Density ?? anytimes tought about that ?
i ve seen that a while ago in the digTutors series where they use a seperate heat emitter to ignite a prePaintet fuelPath. Maybe its a good solution for turbulent explosions.
First - one emitter to create some density and fuel and a few frames later - it will be ignited by a small amount of emitters creating heat on the rightplaces…
Maya fluids suck at retaining their look when you increase the resolution, so an interesting trick is to reduce the voxels on one axis to 3 and scale it appropriately. This will not give you a perfect impression of what the fluid will look like at full resolution but it should help give you the general idea.
Another one is that, what is the best value for texture time and texture origin? Did my expression set them too high for my scene?
It will vary from scene to scene dependent on how your fluids moves, but texture time should be a fraction of time. Try to set one first without touching the other, so animate the texture origin to get the speed at which you want the texture to move and once you are happy with that adjust the texture time to introduce variety.
Just finished the rendering. This is the shot that I made base on your suggestion. It doesn’t look as good as yours but I will keep working on it to understand how fluid works. The texture seems to move really quickly although my expression is really low
This is looking much better, I am not sure about the glow at the start though. If you watch the leading edge you can see where the texture causes the fluid to pop. As you have a texture you will often find the texture will cut away at the edges of your fluid and cause isolated areas that look bad, tweaking your opacity ramp and your texture settings can help here.
Giap,
Nice sim bro. A bit more tweaking is needed, but the movement is good. I looked at your scene file last night and I noticed your emitter density is keyed too long. And your buoyancy is a little strong. I came up with a movement for the smoke you might like. Just need to render it to make sure the res is working. All you would have to do now is create a second container for the base of your explosion utilizing a field to get the motion you like.
tokanohanna,
I made a new one and low down the texture time and now it’s too slow. But overall, I think this is the best I have done so far.
Most likely, looks like we need to put a little bit of pressure on him before the year subby runs out! Must be coming up soon for me ;=]
@Giap Your last sim is looking great! Are you keying the bouyency so it is a lower value at the end?
Aiki,
I didn’t key the buoyancy. I leave the temp buoyancy to 300 and Turbulent at 160 or above, then use the diffusion to control the speed. I also add a negative number to Density buoyancy so it will mix with temp buoyancy. I only key the Density in the emitter and Temp Scale. I figured out that if I turn High Detail Solve from Grid to Off, the blackhole effect somehow disappear 
I’m workin on some stuff right now. Hope to have it up sometime today, we’ll see how the weather outside pans out 
Here are some useful bits of MEL that I use to toggle the fluids when editing. Code is probably a bit overdone but I want to ensure you’ve selected a fluid
This is a MEL script to aid in visualizing the Fluid Texture.
http://www.highend3d.com/maya/downloads/mel_scripts/dynamics/Fluid-Texturizer-4629.html
This code is for toggling the boundary to help modify the resolution Once my res is set I like to work with the fluid in Bounding Box mode…
string $sel[] = `ls -sl`;
string $shape[];
if (`nodeType $sel[0]` != "fluidShape" && `nodeType $sel[0]` == "transform") {
$shape = `listRelatives -s $sel[0]`;
} else {
$shape[0] = $sel[0];
}
string $obj = $shape[0];
clear $sel;
clear $shape;
if (`nodeType $obj` != "fluidShape") {
warning ("Please select a fluid object.");
} else {
int $boundary = `getAttr ($obj + ".boundaryDraw")`;
if ($boundary > 1) {
setAttr fluidShape1.boundaryDraw 1;
} else {
setAttr fluidShape1.boundaryDraw 4;
}
}
This code is to toggle on/off the Fluid Evaluation so you don’t have to dig for it in the AE.
string $sel[] = `ls -sl`;
string $shape[];
if (`nodeType $sel[0]` != "fluidShape" && `nodeType $sel[0]` == "transform") {
$shape = `listRelatives -s $sel[0]`;
} else {
$shape[0] = $sel[0];
}
string $obj = $shape[0];
clear $sel;
clear $shape;
if (`nodeType $obj` != "fluidShape") {
warning ("Please select a fluid object.");
} else {
int $eval = `getAttr ($obj + ".disableInteractiveEval")`;
if ($eval > 0) {
setAttr fluidShape1.disableInteractiveEval 0;
print ("Evaluation enabled for " + $obj + " ...
");
} else {
setAttr fluidShape1.disableInteractiveEval 1;
print ("Evaluation disabled for " + $obj + " ...
");
}
}
ah azshall i’m using your great Fluid Texturizer for some time now, in fact i’m using most of your script!
thx for all ot them!
Great job! :applause:
TheNeverman i just download it and unpack no problem, try unpack it with WinZip that should work
Hi all.I wont lie I’m new to fluids and my pc is too slow to experiment with it so my fluid containers are with (max) resolution of 33/33/33 :>,but I want to show you some of my work :>.
This are all fire and some smoke type simuation that I made with maya fluids (ou and 1 with nparticles xD).
For me the key to a good fire is colors (well I dont find that key yet xD ).
I saw some sims with fumeFX yea they are great,but I dont think that maya fluids are worse than them :>.
http://www.youtube.com/watch?v=GKoVVJhDj5k
Very impressive for such a small resolution ! good color work
the particle thing - i think it was the last ?! - could get much improvement
with all that content in here i mean the whole dynamics forum - but rest
was kick a**.