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phicol
04-20-2013, 09:37 AM
Hi guys
How do i create puffy clouds (stormy scene) and then start a vortex / cyclone in middle of sky and the clouds around the vortex get sucked in and form a twister style rotating tube that extends towards the ground... pheww... what a complex problem :)

any help is appreciated

Thanks in advance

phicol
04-21-2013, 07:50 PM
anyone?

nickdigital
04-21-2013, 08:09 PM
You could create a giant emitter to create the clouds. Then use a combination of wind effectors to create the cyclone effect. I think the cylinder wind one is the one you want but I'm not 100% sure. I did an effect similar to this but in reverse.

phicol
04-21-2013, 09:47 PM
thanks for your reply. do i need to use hypervoxels for rendering or use any third party volumetric plugin for clouds look?

nickdigital
04-21-2013, 11:39 PM
It would have to be hypervoxels. TurbulenceFD is an option but I don't think that'll give you the look you want.

prometheus
04-23-2013, 07:11 AM
It would have to be hypervoxels. TurbulenceFD is an option but I don't think that'll give you the look you want.

I think TurbulenceFd would actually make a smoother volumetric look transition overall, and you can use particles to drive the fluid simulation rotationally, or you can actually use procedural texture in the emitter tab/texture surface and use
any native lightwave procedural such as cyclone or coriolis to get a vortex look.
however..hypervoxels has a more direct way of correcting the noise and light/shading with immediate response, so the shading would be easier to tweak I think with voxels, downside would be the blending of voxels and probably render time.

If you were to use particles and hypervoxels on that, they are bound to a pixel point in space location at the very particle origin and that means puffs and gaps when hv is applied.
You could try using a division grid that you can control subpatch levels on, and add hypervoxels to the objects vertices/not particles and apply a procedural on the hv density channel, set it to world coordinates then use
a procedural cyclone texture perhaps on that...the tricky parti is if you want that extra insuction of clouds nearby, for that you probably need particles anyway.

A mix of Turbulence might also work, you could simulate the whole dynamics with turbulence, render out as image sequence and then map that to a grid with hypervoxels instead.

Michael

nickdigital
04-23-2013, 08:03 AM
No you're right. TurbulenceFD would give much more organic results. Some people have done really nice cloud renders with hypervoxels so that was on my brain. One could also use a mix of both and do a lot of clever compositing.

Greenlaw
04-23-2013, 09:00 AM
I've been getting very nice and controllable vortex effects using Bullet for the leaves in my film. The leaves are using parts, so I think you could do the same with a point cloud and then apply Turbulence or Hypervoxels to it.

About 15 years ago, I created a vortex shaped hurricane cloud for a movie called Storm (or Storm Trackers). I think I used a point cloud that was animated with a twist displacement tool and some fractal displacement and HV applied (version 1.0!) Pretty low tech by today but I thought it was kind neat for the time. You can do this much simpler today with the tools in LightWave today. About two years later, I did kind of an inverse effect for a movie called Epoch--this was a big spinning cloud with a big hole in the center.

Today, I might try the same by rigging a point cloud with bones to twist them and using this as an emitter for Turbulence or HyperVoxels. Or the Bullet trick mentioned above.

A faster rendering method would be to map fractals onto a cone like shape and create a morph to twist it--this will give you a nice twisted pattern. Then, you can use a null to animate it up on Y and rotate around H--the result will be a winding wind effect. Now, nest multiple 'cones' to give it depth (assuming you textures transparency.) In compositing, as some real wind on top. This is the 'cheap' way to do it but since it's all geometry you have a lot of flexibility in how to shape it and how to make it move/deform.

Just a few ideas.

G.

- - - Updated - - -

BTW, there's a trick to making vortex work like this in Bullet. I need to go out now so I'll explain when I get back.

prometheus
04-23-2013, 09:14 AM
I've been getting very nice and controllable vortex effects using Bullet for the leaves in my film. The leaves are using parts, so I think you could do the same with a point cloud and then apply Turbulence or Hypervoxels to it.

About 15 years ago, I created a vortex shaped hurricane cloud for a movie called Storm (or Storm Trackers). I think I used a point cloud that was animated with a twist displacement tool and some fractal displacement and HV applied (version 1.0!) Pretty low tech by today but I thought it was kind neat for the time. You can do this much simpler today with the tools in LightWave today. About two years later, I did kind of an inverse effect for a movie called Epoch--this was a big spinning cloud with a big hole in the center.

Today, I might try the same by rigging a point cloud with bones to twist them and using this as an emitter for Turbulence or HyperVoxels. Or the Bullet trick mentioned above.

A faster rendering method would be to map fractals onto a cone like shape and create a morph to twist it--this will give you a nice twisted pattern. Then, you can use a null to animate it up on Y and rotate around H--the result will be a winding wind effect. Now, nest multiple 'cones' to give it depth (assuming you textures transparency.) In compositing, as some real wind on top. This is the 'cheap' way to do it but since it's all geometry you have a lot of flexibility in how to shape it and how to make it move/deform.

Just a few ideas.

G.

- - - Updated - - -

BTW, there's a trick to making vortex work like this in Bullet. I need to go out now so I'll explain when I get back.

Interesting to hear about a bullet trick.

yes...the hardest part might be the actuall tornado tube that he wants coming down maybe...so many ways to do things, some faster...and some more realistic.

Areyos Alektor
04-27-2013, 08:25 PM
The HyperVoxels is fine for it. It takes a HV Emitter to generate particles with ParticleFX, use several Wind controllers : 1 (or more) for mixing the tornado with clouds, 1 order to twirl the particles and 1 for draw down.

Bullet Forces ?
http://www.youtube.com/watch?v=tyYzvmJokYU&list=PLBscyc2_NuEBa3yGB4AycBuZHd4KRvS2p&index=11

I'm curious to see it :)