Tornado/rain/particle effects

Started by gradient, January 16, 2007, 11:45:15 pm

Previous topic - Next topic

glen5700

I modeled a tornado in Rhino using some lofts and brought the object into Terragen 2 but had no success on applying clouds to the object. My thought was to get the clouds to fill the volume of the object.

We probably need a particle generator with basic forces that clouds (3D) could be applied to.

Glen

buchvecny

well the .obj support isnt 100% yet.

Oshyan

The volumetric (cloud) shader can't currently be applied to objects.

- Oshyan

micter

Hi !

In the same sort of things, I tried to apply a warp or displacement shader to 3D clouds, without success.
Observing what 3Dguy and Sandpiper have done with their distorded terrains, I thought we could do the same with the clouds, and make some clouds columns, or strange things like that.

It seems that for the terrain distorsion, we somewhat obliged to put a "compute terrain" shader at the beginning and at the end of the list of nodes. So I tried to put a second "atmosphere" shader before linking to the planet node, but without success again.

Does someone tried something like that ? I tried many many things, but can't remember exactly what. The only thing I remember is the result : clouds without distorsion !!!

Maybe we should try something with 2D clouds, I don't know...


Michaël (micter)
http://micter.free.fr



Njen

I know that JimB and myself were trying to have clouds follow the terrain with not much success. I don't think much can be done with clouds shaping at the current stage of TGTP. Maybe in the future we will recieve better cloud sculpting tools.

Dark Fire

The clouds definately need a lot more customisability - it just occured to me today how interesting it would be if we could import real weather data (clouds, rain, etc.) into Terragen, similar to the way we can import real terrains.

Will

Quote from: Dark Fire on January 19, 2007, 01:13:18 pm
The clouds definately need a lot more customisability - it just occured to me today how interesting it would be if we could import real weather data (clouds, rain, etc.) into Terragen, similar to the way we can import real terrains.


you can, Here http://forums.planetside.co.uk/index.php?topic=544.0

Regards,

Will
The world is round... so you have to use spherical projection.

Oshyan

The one major thing to remember about the clouds as opposed to terrain is there is *no displacement*. Cloud shape is based on Density Shader input, which by default is connected to a fractal noise type function. Trying to apply displacement to the clouds directly won't work; neither will trying to apply *displacement* to the noise shader connected to the Density Shader input.

To affect the cloud shape you'd need to work directly on the color values of the Density Shader's input node. This means your Warp, or any other shader you want to affect cloud shape, should be connected to the default Density Shader power fractal node, or at least connected to this Density Shader input (which interprets color values as volume).

Remember that displacement will have no effect, your changes will only be those that happen in color space, so mess with what's on the other tabs and ignore displacement - all the other settings should have some effect. You can either use the main Input connection of the default Density Shader to get a mix, or use the Blend Shader to get a kind of "masking" effect. The Warp effect is setup a bit differently but again it needs to interact with the color values of the default Density Shader, so keep that in mind.

Granted the options for working with clouds aren't as powerful as they could be, but you still have a whole lot of flexibility if you know how the system works. Simply assuming it works like terrain (e.g. using displacement) is the biggest misunderstanding most people have. Hopefully the above will get you to a point where you can at least experiment successfully.

- Oshyan

micter

Thank you for your suggestions and for telling us how it works.
I'll try to play with this "density shader", and see if I can get something with it.


Michaël (micter)

Dark Fire

Quote from: Will on January 19, 2007, 01:14:16 pm
Quote from: Dark Fire on January 19, 2007, 01:13:18 pm
The clouds definately need a lot more customisability - it just occured to me today how interesting it would be if we could import real weather data (clouds, rain, etc.) into Terragen, similar to the way we can import real terrains.


you can, Here http://forums.planetside.co.uk/index.php?topic=544.0

Regards,

Will

Thanks - I will have a lot of fun with real weather systems. However, the ability to import rain data and automatically generate various densities and sizes of raindrops and the ability to have them fall and be affected by wind in animations would be useful. A rainy and windy evening would be a lot more realistic than the thousands of beautiful mountains and sunsets created with Terragen...