View Full Version : Locomotive/Train - smoke, steam and sparks

11 November 2003, 09:24 PM
Hi guys,

how do I add smoke to my train - I want the smoke to blow upwards when the train is stationary, and for it to blow backwards as the train moves leaving a trail that dies out.

I would also like to add steam coming out of the pistons and coliding with the ground and then bounces off - just like a train would when it starts the engine

Here is the project I am working on

11 November 2003, 12:15 AM
The smoke is extremely simple my friend. You need to set up a directional emitter with a small spread, maybe 45 degrees or less, and have it emit in the Y direction. Then place that emitter in the smokestack and BAM, you're golden. You can also add a turbulence field to the scene to mix up your particle motion a bit. To render, you can either use cloud particles, or even faster and better, would be sprites. If you need details on some of this, check out:

This method will allow the smoke to emit upwards always, with the particles being left behind as the train moves.

For steam you can use a similar method except you want them to emit in whatever direction is out from your piston. Connect them to a gravity field and use your plane and/or track as a collision object. Again, you can use clouds or sprites. Sprites will render far faster but you have to render in passes (sprites only render in the hardware renderer and I assume you will want to use software rendering for your train).

If you do not know much about particles, this will pretty much sound like a lot of alien-speak to you but check out that link I pasted earlier and it should get you on the right track because there are lots of tutorials for smoke and clouds and the like, as well as basic particle stuff that would just be too tedious and redundant to write out here. If you get stuck on anything, post again and I'll try to help.

11 November 2003, 10:06 PM
Thanks, I will go through the tutorials and get back to you if I run into any problems.

12 December 2003, 04:26 PM
hi guys,

here is an image of my locomotive, please help me figure out the smoke

I would like it to look like smoke - right now it just looks like blobs

Any ideas????

12 December 2003, 04:39 PM
You're using Blobby type particles. Change it to cloud type particles. Then, in the hypershade, create a Particle Cloud shader and assign it to your particle object. Check out the tutorial on creating clouds at for some tips on using the particle cloud shader. Post some pics when you get it updated and I'll try to help you further.

12 December 2003, 04:53 PM
hi WhiteRabbit,

I am using the cloud S/W option - but it still comes out that way, I even applied the cloud shader - that's what you see in that image.

Any other settings I need to change?

12 December 2003, 05:54 PM

You may have surface shading on, and have assigned a regular shader. Make sure that's not the case. I turned out the first image using the settings in the second two. The expression on mass is a creation expression: particleShape1.mass = rand(1,2);

There are procedural textures mapped to both the color and the blob map, both are clouds and I didn't mess with the cloud textures at all to get the image you see above. The only thing I modified in the texture was to make the cloud color2 in the color channel a little gray instead of white. Using these settings ought to give you what you're looking for and you can adjust from there.

12 December 2003, 07:19 PM

let me try out those settings.

Do you have anything on your rgbPP field? I have a ramp shader as my color and another one for the lifespanPP - could that be affecting the outcome?

12 December 2003, 07:51 PM
What is the ramp shader on lifespanPP connected to? You want an expression of some sort to generate a random lifespan, a ramp is likely to just make the lifespan get shorter/longer as time goes on, which may not be what you want. You also need to change lifespan type to lifespanPP Only, something I didn't realize till recently. As for rgpPP, as soon as you change the render type to cloud(s/w) then it overrides rgpPP. If your particles' color change over time with a ramp, it can be very handy to have rgpPP use the same ramp as your shader color, because although rgpPP will have nothing to do with the actual software render, it will color the particles in the viewpane, giving you some feedback. In this case, you don't want the color to change over lifetime so you probably don't care much about the color in the viewpane. You DO want them to change opacity to black near the end of their lifetime so they fade out and don't pop, I forgot to add that to my little demo.

12 December 2003, 09:24 PM
You DO want them to change opacity to black near the end of their lifetime so they fade out and don't pop, I forgot to add that to my little demo.

how do I do that? what field do I adjust that in?

You also need to change lifespan type to lifespanPP Only, something I didn't realize till recently.

how do I change this too

hope you don't mind my many questions - I am still trying to figure out maya.

12 December 2003, 09:31 PM
I am trying to achieve smoke similar to this image,

12 December 2003, 09:45 PM
That image would just require a lot of particles with a smaller radius. I used less with big radius. Changing the opacity you can click on the opacity tab under your particle attributes and click on Add Per Particle Attribute for opacity. give it a ramp so they fade out over their lifetime. Do some of the tutorials at:
to learn some of this more basic stuff.

12 December 2003, 10:06 PM
here is what the smoke looks like with the help you gave me.


12 December 2003, 04:09 PM

thanks so much for your help

here is an update, after playing around with the settings - tell me what you think.

12 December 2003, 07:19 PM
Looks fantastic I think. If you want it to look more like that photo you posted, you can add a life color to to so it's darker when the smoke first comes out of the smokestack and then gets a bit whiter at a certain point. I think right now you just have a color set, you'd just have to right click on 'color', choose break connection, then click the tab next to 'life color' and then edit the ramp however you want to get it to be this way. But it looks just fine the way it is. Nice job.

10 October 2005, 07:45 PM

Which fields did you use on the particles (turbulence, air, uniform, ...) to get the smoke in a bow leaving the chimney of the train ?



10 October 2005, 11:00 PM
Guessing the emitter had an initial velocity, plus a little spread. Differed the mass and lifespan of each particle up a bit, and let them lose their velocity a bit (conserve of like 0.9-0.95 or so), so it wouldn't keep up with the train.

This is where you experiment and find good results. Being spoonfed this stuff makes you a worse artist.

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