Maya VFX Series: Smoke Effect in Maya

hello everyone this is Reza and welcome to another video on effects in Maya in this session we're gonna focus on how to create realistic smoke using fluid containers so I made another video the other day and that was about how to create fire so if you haven't watched that make sure to check it out I am I did give you guys a lot of tips and tricks on how to use different attributes within fluid container to kind of bring you guys up to speed in this one I'm gonna pick up where I left off in the previous video but the focus is not gonna be on temperature is going to be rather on density so this is a scene that I've prepared it's a handheld camera capturing a scene where a spaceship is taking off or making its move but there is no smoke trail so that's what we're going to create just so you know it's a simple expression that I assigned to the shake attribute for me to give me this type of a random noise it's fairly straightforward very simple so without any further ado let's let's get into it first things first I'm going to switch to effects menu and I am going to create a fluid container it's the 3d fluid container I'm gonna reset the settings so my setting matches yours I'm going to enable or leave add emitter on rather and parent it to the container emitter type I want that to be a volume and apply probably it would be a good idea for me to switch back to perspective and have a much better angle to work with now I've got my emitter and that emitter volume emitter with a long access which is quite useful if you want to direct your fluid towards a specific direction much better than Omni I found now before I start I'm going to go to channel box and through volume shape change the shape to something like cylinder kind of makes more sense to have that rather than just a box in here okay time to make some adjustment so I'm just going to bring this into position maybe fast forward the video mute the audio and do that you don't need to just sit down and watch me doing this you so that's done let's do the parenting so I do have if I go to the herbs curve I do have a control curve here and I've parent parent constrained the entire model to that curve I'm gonna do the same thing for the emitter let's select the the driver and then the driven which is the emitter I'm gonna go to rigging constrain I don't look at the option box maintain offset is on and parent constraint now if I play you can see the emitter follows now here's the tricky part that this guy does not follow and you can try parenting this to anything you want still not going to follow the way you want now the trick for this guy is to select the fluid go to Auto resize and auto resize it that's it and when you rewind the container is going to follow the model so that's that let's go through some attributes here and adjust the resolution so first things first I'm just going to go to fluid fluid emitter basic fluid attribute I have hundred percent as my rate I'm gonna opera's it to 300 also I've got only ten voxels resolution as my base which is way too low probably start with 50 that should do it just gonna zoom back a little see what I'm doing and play probably would be a good idea to hide all of my lights for now probably Alt be to go to black background so you get to see what's going on and now we have something now this something is not correct it's dotted it looks really bizarre and usually with fast-moving object you do get that the way to fix it is actually very simple you go to a mirror attribute and you scroll down into fluid attribute tab and that's the attribute that you need to enable motion streak now if I go ahead and rewind you're not gonna see any dotted line it's all connected now now from the same menu while I have this open I'm just going to reduce that fluid drop off to something like point two and I did that in the previous video as well just because you get a much sharper result so it's not gonna eat in all the borders it is going to give you the actual fluid the 300% rate that you assigned to the emitter okay looks better next is to tweak my fluid emission turbulence and emission speed attribute now if I open this I have set this to gradient I want a little bit of randomness I would like to introduce some turbulence maybe three you may not see much of a difference right now probably if i zoom in a little we can see just a little bit of randomness that we just introduced but it's still quite straight there is no realism to live and to travel in this 3d container that we have it's very tamed so far very staged there are two I don't like this the reason that this happens especially in fast moving object is velocity and that's what's missing we do need inherit velocity and as soon as you introduce inherit velocity then you start seeing that push coming out of this exhaust and pushing this smoke into the container and only then we can see the effect of the turbulence and only then we can see a little bit of motion that is happening now you may ask where to find inherit velocity it's sitting on your emitter emission attribute speed attribute just need to find it here I set it to add and only then you get that inherit of velocity now I'm gonna start with 50 and may increase that but now if I play you can see I'm getting some really really cool results now while I'm quite happy with this pattern still lacks detail now I my trick in this case is to Opera's max resolution on my auto resize now I'm not going to oppress the base resolution because it's going to slow down my scene so let's start with max resolution on my fluid container and then we take it from there if we need to increase base resolution so be it you are gonna do it later Auto resize max resolution maybe double it for now I'm a triple that later but we see how we go now I'm gonna go another take that's much better actually I don't see that graininess and noise in the base I kind of like that while I have this here I would like to give this a cone shape and I need to set some resize margin for this again in the same window I'm gonna set the resize the resize margin to something like three again these are just random numbers for now I may add to that later now it's kind of killing the the smoke but we are gonna introduce more smoke so that hopefully should do the trick for now I'm getting that diamond shape that I like I completely lost the trail because probably I don't have enough smoke so that would be next thing to do so let's select the emitter and introduce more smoke if we still don't see anything then I have no choice but to reduce that max margin so on Luud attribute that's where you introduce more density coming out of the emitter I have a one unit per box or per second I'm going to start with six and see what we get that's better so you can see I am getting that cone shape the max resolution of 400 is now showing better and I'm getting my trail back don't increase that too high otherwise the trail will never die as a matter of fact speaking of which we do need to go and set some some dissipation and buoyancy for this thing because it is kind of rising and just a little bit but I don't want that and it basically stays so we need to go to the brain of our simulation for the container which is inside contents details and density again very important to master these attributes over time some of them are quite important and you just have to know what you're doing and tweak them so let's start with density buoyancy set to one I'm just gonna set it to point one because I don't want that to I don't want that to rise you can go to dynamic simulation where the gravity is because we don't really need gravity dynamic simulation gravity set it to something like two again it's just one of those things it's not gonna be a deal breaker if you don't do it but again while I have this here I'm gonna introduce just a tad of damp I found that damn works really well very subtle value just to control the effect so if it's set to zero the smoke gets out of control really quickly if it's set to a high number and when I say high number I mean point five considered high number four damp then everything gets to soft and with pretty much low energy so something really subtle like point zero one two point zero three for this scene scale works just fine so let's see how that looks good next is to add some external turbulence turbulence field now I can just go ahead select the fluid and go to effects and fields and solvers and assign turbulence note in here but let's give this guy a try first and see what we get and if we're unhappy with that then we may use turbulence because that one has got attenuation and more other controls this one is a very simplified version of the force field note I really don't need a situation at the moment because the emitter is attached to the object so really doesn't make any sense for the strength I may go with just good old one frequency works just fine let's see what we get yeah that that wildness I like about it it doesn't have much swirl though so I'm gonna go to velocity and I'm going to introduce just a tad of swirl see what we get that's much better really I really like that and again if you want that to die soon that that trail I actually don't mind that much because smoke coming out of jets or fast-moving plane these type of smokes linger do linger a lot so you can set some dissipation but don't make it too high because at the end of the day you want this to to linger all right so this dies much quicker now but I think that's that would be as far as I go just value of one because I do want this to linger now one attribute that I really use when I have fluid air but doesn't expand outwards is is high detail solve and this this reduces diffusion on density and velocity I do have both works really well if you have rolling clouds if you have explosion and if you have in this case smoke so high detail solve you can just capture velocity if you want or just capture density I do have both in the scene and I'm gonna set it to high all grits the solver that I do use a lot is navier-stokes the other one spring mesh works for up and down and back and forth movements very quickly and if you have that and you have velocity then feel free to change the solver to that so you can see a drastic now when I play all in the southern you actually do see the smoke coming out of exhaust and it's much thicker it's fuller and we didn't add to the resolution it's not really that expensive now if you want to introduce some soft steps so that soft step I set it to two now and basically solver performs calculations per frame and increasing that value will improve the stability of the simulation and then the fast moving fluid so again use it when you have a fast-moving object that solver performs more calculation per frame especially if you have high density grid and use high detail solver then substance do become very useful and then we have solver quality here and it kind of increases the number of steps used per solver so I'm just gonna probably use this 25 in here and yeah I think I'm getting a much better result now overall so you can see I'm getting extra amount of calculation per frame I had found out that making it too high will completely change the look of my simulation now one thing we haven't done yet is shading now without a before I go into shading I can go into lighting to begin with an enable self shadow and increase that to a something like 0.9 now this actually introduces tell you what I'm going to set the display to none display boundary draw to none that's much better so I get to see what's going on here so yeah lighting introduces a really nice self shadow effect and gives a little bit of depth to my simulation so that looks nice and if I scroll up now I have this where I can introduce a little bit of transparency or reduce transparency if I want and with color I can just give this a ramp and color it incandescent probably don't need that because I haven't introduced any fuel or temperature and opacity can work for me based on the effect that I'm trying to achieve a little bit about transparency edge drop-off and drop-off shape works really well if you want to create something like candle flame because it kind of eats a little bit of top and bottom or both ends of my smoke as you see which is sometimes the case when you have a candle flame and the other option that you can play around with is opacity and did we did use that in our fire simulation I'm probably getting a much better result now using opacity because I don't want that full thick trail like a marker the smoke should break up at some point and that effect it is happening now so I think I'm in a really good place the only thing that I need to tweak is this color and I do give this a sort of a ramp and again I'm repeating myself over and over again it really comes down to what look you have in your reference and how you tweak that based on that you are going to tweak your end result so instead of having it set to constant I can have it set to density you yeah something like that should do the trick really now let's go to the original camera camera front and let's let's cash out the scene and again this is something that we talked about in the fire tutorial but we are going to do that again so I can go to flew it well in FX sub menu I can go to n cash create a new cash Maya fluid and just cash out my simulation I can set this one to set it to smoke and it's gonna take a while but I'm gonna pause the video and I will come back with a full plate last alright now everything's been cached and I did a play blast I made a three minor changes I extended my time frame to 200 and if I go too slow a shape I increased my pace resolution from fifty to sixty only ten more voxels and in shading I tweaked the opacity a little so I am I noticed that it's just too much fragmented the whole smoke so I tweaked the texture to this the rest is really much the same and again I brought the dome light back and did a quick blade blast on that and that's the play blast you so here's the playblast I'm quite happy with it um still max resolution can be slightly improved based resolution can be increased just a tad but apart apart from those minor changes I think I'm quite happy with the overall movement of the smoke the amount of dissipation the amount of density I have an amount of turbulence maybe just a little bit of you know I would I would tweet transparency just a little bit make it more transparent and opaque but these are all those changes our creative decisions that you can make based on the the brief that you have and of course my suggestion is to always always study reference and try to make it as close as possible to the reference okay that's it for me I hope you enjoyed the tutorial and see you guys

Channel: SARKAMARI

Views: 11,053

Keywords: Autodesk Maya, Reza Sarkamari, Smoke Simulation, Fluid Simulation in Maya, 3D Container, Effects in Maya, Smoke Effects in Maya

Id: HBXWCYwa8Jw

Length: 24min 16sec (1456 seconds)

Published: Fri Apr 17 2020