Candle Flame Thin Smoke

[Eucalyptus]

So I know there is a "Wispy Smoke" shelf tool in Houdini, but it's not really what I would expect. If you've ever blown a Candle out before (and I've done this hundreds of times the past week for Lookdev, heh) you know that the smoke that briefly trails out of it is VERY thin, precise and almost made up of lines.

I have an image in my head of a few particles floating upwards from my "wick" in a sort of random, noisy direction and then using a Trail SOP to cause them to streak, hopefully looking like smoke, but... I'm not sure quite how to achieve this, or rather how to have it look like connected smoke instead of just lines streaking. Is there a way to cause 2 of the particles to "connect" and stream together, and make it look more like an opaque ribbon (or... you know, smoke...)?

Furthermore, is there a way to have the Trail effect appear in the viewport on my particles (as a line/ribbon)?

Cheers and appreciate any tips or suggestions for a basic "Candle Flame Smoke" effect. Simple is best - just learning Houdini.

[xmetallicx]

You could use an add sop to connect the upwards particles as a line, duplicate, shift it one side and then mesh it together like a ribbon using a rail + skin sop. Then have xray kind of shader to help give you the look. Though this method will probably have you tweaking alot.

- Joel

ribbon.hip

[lukeiamyourfather]

It could be done entirely in SOP depending on the shot, for example if a hand runs through the smoke that wouldn't work. If using DOP it will require very high resolution simulation to get the detail of the thin smoke.

[Eucalyptus]

It's actually just a candle that gets blown out by an unseen force, and I want to have smoke come out of the wick after the Flame (pyro) disappears. So no hand or anything interacting with the smoke really.

To accomplish this entirely in the SOP level would I use a particle + trail SOP still, or is there another simpler way?

Thanks

[vi_rus]

Take a look at the gridless advection

[Eucalyptus]

Take a look at the gridless advection

https://vimeo.com/54646735

You have my attention, as that looks really great. I can't seem to find much documentation on the process of applying gridless advection though?

[Eucalyptus]

You could use an add sop to connect the upwards particles as a line, duplicate, shift it one side and then mesh it together like a ribbon using a rail + skin sop. Then have xray kind of shader to help give you the look. Though this method will probably have you tweaking alot.

- Joel

Edit: Didn't see you included .hip file, Thanks Joel!

Edited January 16, 2013 by Eucalyptus

[Eucalyptus]

Still looking for any other ways to get very thin, detailed smoke like that of a Candle.

The ribbon method is sort of working, but isn't quite organic enough to be convincing smoke. I'm not sure how to create a gridless advection render, and from my research it looks like it takes ridiculous amounts of time to render so...

Is there another way to accomplish this in just the SOP level? It's just a basic shot of a Candle being blown out, and I'd like some realistic smoke floating up after. I've been tweaking with the "Wispy Smoke" shelf tool but it seems to be too... how do I put it... noisy?

[Solitude]

Hey guys,

Here's my stab at it -- a little hacked together, not optimized at all, but it's a good start I think. It's using advected points to render.

P.S. I didn't spend much time on the render, and I'm not very familiar with mantra.

pyro_candlesmoke.hip

Edited January 17, 2013 by Solitude

[Eucalyptus]

Solitude!

I get an invalid cam1 OP_parameters name: 'trange' when I render a frame of this - but regardless, it looks great!! Thanks for throwing this together.

I'm going to study it and see if I can understand this advecting points me and you were chatting about yesterday.

Thanks again!