Hi, really good modelling of the objects in the scene.
As for the smoke you shouldn't use a cone. It isn't right from a fluid 
dynamic point of view.

The smoke should remain laminar for a while, I mean like a stream, then 
it makes a kind of transition from laminar to turbulent. Is from this 
point on that the smoke expands in a chaotic way.

Anyway really a great image.

Massimiliano.

Julien Gourdon wrote:
> Hi all
> This is one of my first attempts to make a kind of cigarette smoke.
> It is a 800x600 with AA 0.3 render, with radiosity and 4 (I'll explain)
> light sources (the 'sun' is an area_light). It took 4 hours on my XP
> 2000+ to render.
> The smoke itself is a cone filled with a media whose density is a
> function of my own. I had lots of pbs with the function, because if I
> want a shape that matches most a real cigarette smoke's one, the
> function must be very complex, and the render time reachs the sky. And
> because of the color too. It seems that if I want blue reflects in the
> scattering media, I need to set up his color to something like <1, 1,
> 0.5>. I understand it for absorption, but what about defuse light in
> scattering media ? Am I forgetting someting ? Finally I choose a
> scattering media with a very little extinction, and some emission and
> absorption.
> Not much to say about the ashtray and the cigarette (and no words about
> the ugly environment :pp). The cigarette is just two cylinders with
> color_maps. The red glowing part (sorry for my bad english) is two mixed
> isosurfaces, one filled with a grey pigment, and the other with a red
> emitting media. There are three red fading lights around the glowing
> part, to make a red glow on the ashtray and on the smoke. This surely
> needs to be improved, because of what happens on render time :(
> 
> Any comments, suggestions, questions ? Does anyone know how to make
> realistic cigarette smoke ?
> 
> 
> ------------------------------------------------------------------------
>

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Massimiliano Cirri wrote:

> Hi, really good modelling of the objects in the scene.
> As for the smoke you shouldn't use a cone. It isn't right from a fluid 
> dynamic point of view.

Humm, didn't think of that. But the cone is just a container. The trick 
is in my density function.

> The smoke should remain laminar for a while, I mean like a stream, then 
> it makes a kind of transition from laminar to turbulent. Is from this 
> point on that the smoke expands in a chaotic way.

Thanks for the advices. I tried to take care of what everyone said, and 
here is where I am right now.

> Anyway really a great image.

Thanks a lot. But it's just a WIP ;)


-- 
Jul### [at] cnedraorg
http://www.cnedra.org

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