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DeKo-LT
11-22-2005, 02:01 PM
Hello,
i create animated Clouds with Fluids. Now i have problem with setuping Fields.
I must create swirling hole over castle, but i try vortex and have strange result with strething and same clouds animation.
I'm pretty newbie in maya(mostly i use 3dsmax) and maybe i do something wrong? Maybe better to use some object as collision?
PLEASE HELP, i really want to learn maya... :sad:
Here is my result at this moment, without any turbulence field:
http://deko.cgtalk.lt/cloudsstormTest07.JPG
Thanks!

Duncan
11-22-2005, 11:06 PM
It looks like you have a fluid that is purely textural. In order to animate it you will need a dynamic velocity grid as well as need to make the coordinateMethod = Grid. The velocity will then push the texture coordinates around swirling the texture(you might also need a dynamic density grid). This only works for a bit, however. As the texture moves it will smear and lose the puffy look.

Duncan

FloydBishop
11-23-2005, 04:22 AM
...you will need a dynamic velocity grid as well as need to make the coordinateMethod = Grid. The velocity will then push the texture coordinates around swirling the texture(you might also need a dynamic density grid). This only works for a bit, however. As the texture moves it will smear and lose the puffy look.

Where do you set this value exactly? I don't see it in the attribute editor anywhere. Maybe I'm not looking in the right place? I found the spot where you change the density to a dynamic grid, but the coordinateMethod = Grid stumps me.

I'm an animator, so the deeper Maya stuff is still a bit new to me. I apologize if I'm asking a stupid question. I've looked through the docs, and I see coordinateMethod mentioned, but I still can't seem to find how to set this.

Thanks in advance :thumbsup:

In regards to the first post, in addition to fields, you may want to add a piece of animated geometry that will mix up the clouds like a blender... just be sure to hide that helper geometry prior to render.

Animate the geometry, then select the fluid and your geometry.
Fluids > Make Collide.

You may find that it gets you closer to what you want a lot faster than guessing at numbers for field settings.

AndersEgleus
11-23-2005, 06:46 AM
Where do you set this value exactly?

It's in the Textures section of the fluid shape, right under Texture Type.

DeKo-LT
11-23-2005, 08:56 AM
Very thanks, for reply
i try earlier with nurbs collisions(nurbs cylinder over temple), but have very strange result:
http://deko.cgtalk.lt/cloudsstorm8_collision.jpg

I also try change High Detail Solve and Grid Interpolator to hermite, but this don't help. My Density and Velocity set to Dynamic Grid and Cordinate Method is also set to Grid. I don't know what to do. For now, I just want to make hole in fluids, swirling i try later create with particles.

Duncan
11-23-2005, 06:01 PM
It looks like your velocity may not be what you think within the fluid. You should turn on velocity draw to see if you are getting arrows swirling around the center( as opposed to
up/down velocity). The decay and magnitude of the vortex field will be critical for a good effect. It looks like you have a great deal of velocity in the center( perhaps a high magnitude coupled with a bounded vortex or max distance set).

The dots indicate that you have a very thin density( increasing the fluid shading quality will get rid of the dots, but you are better off avoiding the thin density by getting the force to apply better ).

Make the coordinate speed 1.0 as well.

To create a hole you will need the opacity input to be set to density grid, instead of a gradient. This means that to get the same look you will need to paint density into the fluid(using the paint fluids tool). You could flood fill the fluid with a base level of density then paint a hole in the middle.

Also, depending on the look you are after, a little negative texture implode may help.

Duncan

DeKo-LT
11-25-2005, 08:56 AM
Very Thanks Duncan!
It's seems to be little complicated to use Opacity Input for density, i use it for forming clouds shape, in other words for forming empty area between clouds. Other problem that painted density spray away and don't stay in one place, that i want... :sad:

Anyway big big thanks, I will try different method.

P.S. here is my scene: CloudsStormTest10.zip (http://deko.cgtalk.lt/Maya_tmp/cloudsStormTest10_.zip)
i think, basic clouds animation isn't bad, maybe someday have need of it. :)

Duncan
11-25-2005, 07:38 PM
By default the texture will move more slowly than the density when using coordinate grids. You need to make the coordinate speed = 1 and then lower the magnitude on your vortex field. If you just want a static cloud shape and not a moving effect you can run the simulation until you reach a frame you like, then cache the initial state, turn off the velocity grid and make the density grid static.

Duncan

DeKo-LT
11-30-2005, 08:49 AM
Now I unerstand my mistake. :banghead:
Many many Thanks Duncan, you are new God for me :thumbsup:

RoundRobbin
12-01-2005, 04:23 AM
In order to animate it you will need a dynamic velocity grid as well as need to make the coordinateMethod = Grid.
Duncan

will a pond fluid give you the same results or is it unique in that it just won't work for ponds...

is it because its needs to be enabled by a spring mesh,
anyway to by-pass this and still maintain control with forces.
thanks in advance

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