Text SOP to constrain then dissolve into smoke

[John Pilgrim]

Hi all,

I'm looking for guidance and strategies for transforming a sop into smoke, which then drifts away and dissolves.

The shot is an opening title sequence for a film, in which the title "SOUL" appears onscreen as extruded text for a second or so

and then, from one frame to the next, loses it's rigid nature and becomes a fluid smoke, initially in the exact same shape, which drifts and dissolves away.

This is not what I want, text emitting smoke:

I'm at a loss for how to "fill" the volume of the letters with smoke and then release the smoke to drift away subject to forces of the sim.

Ideally the smoke would completely fill the sop all the way out to the cusped edges. If this is impracticable, it can be handled via subsequent compositing after Houdini.

I'm sure there are multiple approaches and I'm interested to hear them. Would that it were particles and dissolving into drifting sand, I'd be OK, but am not familiar enough with pyrofx to do the same with smoke.

Thanks in advance!

Very Best,

John

[Erik_JE]

Create your own fuel field by making a volume from your text. You would need to make it pretty high-res to capture all the detail tho.

EDIT: Maybe this don't make much sense if you are not familiar with the pyro tools.

Edited September 12, 2011 by Erik_JE

[ehsan parizi]

I'm not a fluid expert, but I remember some stuff from a school project that I did like a year ago, take a look at the attached file.

It's not exactly what you want, but I think you can start from there!

smoke_fluid.hipnc

[stevenong]

Think this should help: eetu's lab

Cheers!

steven

[John Pilgrim]

Thanks for the input so far!

Ehsan's suggestion gives this and, with a little compositing finnesse this

Steven/Eetu's give this

Ehsan's is closer to the art direction, in that it is a snap transition. But at the start of the sim, the smoke is already considerably larger than the text sop, requiring some compositing to achieve the transition.

Steven/Eetu's is a wipe not a instantaneous release of the constraint, but the smoke more closely originates from within the text volume.

I will pursue Erik's fuel field.

Still open to other thoughts/refinements.

John

Edited September 13, 2011 by John Pilgrim

[Rudinie]

Another approach that might proof useful is one i've used in the beginning of this one: http://www.vimeo.com/27872334

It's just particles that are advected by a fluid sim and released based on a noise mapped onto the characters.

That way it's easier to control the dissolving of the characters instead of all at once.