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jortdevries
12-08-2008, 09:53 AM
Hi,

I'm trying to simulate a little mountain in c4d, and would like to make the snow that I've done allready with particles, wind and turbulence, stay on the surface / geometry.

Is it possible to make the particles stay on the objects in the scene? Should it be done with adding some cloth tags, or is it really another way of making the snow..??

Thnx allready!

ahven
12-15-2008, 04:15 PM
I have used RealFlow to make snow for roofs. Just triangulate the geometry
when you export the object. Export as Obj and open in Real Flow.
Then make realflow particle daemon as well as gravity.
Put geometry under the particle flow and simulate.
Then just import the mesh into Cinema 4D.

You can also brush the snow later in Photoshop. Ive used all possible techniques.
Also modeling with metaballs is possible for snow.

For material you need to add some luminance value and some nice bump map.

see my work here:
http://www.kraphik3d.com/images/yllas_villas_1_www.jpg

Lex1968
12-17-2008, 07:59 AM
...., or is it really another way of making the snow..??

Hi Jort,

I'm not sure If you want an animated version of this, but I recently added some snow with the help of the Falloff shader.

http://www.studiolex.nl/downloads/cgsociety/snow/Kerstkaart-05.jpg

http://www.studiolex.nl/downloads/cgsociety/snow/Kerstkaart-05-detail1.jpg

Check the Mountain scene in the R11 demo of C4D. .../MAXON demo/CINEMA 4D R11 Demo/Scene Files/Advanced Render/Sub Polygon Displacement/Mountain 01/Mountain 01.c4d

http://www.studiolex.nl/downloads/cgsociety/snow/Mountai-01.png

...and play with the settings. The trick is that the Falloff shaders reacts to the XYZ coordinates of your mesh. In this case I choose only to react to the World Y axis. It is a combination of the Falloff shader in the luminance channel AND a copy of that same channel in the Displacement channel...

http://www.studiolex.nl/downloads/cgsociety/snow/falloff-6.jpg

http://www.studiolex.nl/downloads/cgsociety/snow/falloff-steps.jpg

I hope that helps.

Cheers, Lex

Magnus3D
12-17-2008, 08:04 AM
Interesting trick using the Falloff shader hmm.. but it won't generate any thickness to the snow, it will only lay as a thin sheet ontop of the mesh. I'd love to have a way of producing thick snow covering a mesh/surface. Any clue how to get that effect ?

/ Magnus

RandyLeeBlain
12-17-2008, 07:29 PM
Interesting trick using the Falloff shader hmm.. but it won't generate any thickness to the snow, it will only lay as a thin sheet ontop of the mesh. I'd love to have a way of producing thick snow covering a mesh/surface. Any clue how to get that effect ?

/ Magnus

Crank up the displacement height. Turn up the SPD and turn rounding, map rounded geometry on(app not open). Mask some areas so they do not get "snow" to show the "snow" height better.

HTH
Randy

Joseppi
12-18-2008, 01:18 AM
Interesting trick using the Falloff shader hmm.. but it won't generate any thickness to the snow, it will only lay as a thin sheet ontop of the mesh. I'd love to have a way of producing thick snow covering a mesh/surface. Any clue how to get that effect ?

/ Magnus

Magnus,

In Lex's example above (the spheres) the snow is really piling up high in the displacement channel sample on the far right... it's heaping up on the sphere going out the top of the frame. Just increase the displacement and it would seem to pile up...

Joe

jortdevries
12-18-2008, 09:03 AM
Thnx guys, really usefull posts!! I've done the snow just with particles at the moment and added some snow on top of some object by just adding some geometry, had no time to totally rebuild it...

The shader that Lex was talking about seems to be very interesting, will try to play with that one for sure, to use is with next projects!!

DaveD
12-18-2008, 10:46 PM
It is possible as far as I know and I thought at one time I had downloaded a similar example. I think the example actually used thinking particles to simulate fire and crawl up a tree. It could probably be adapted for this use. Come to think of it aren't there some TP preset examples in the content browser that could perhaps be modified?

I had some small amount of success with a similar project using a simple deflector and setting the elasticity to zero. My falling snow was just piling up on a flat plane though, not conforming to any curves.

Cinemike
12-19-2008, 02:37 PM
It is possible as far as I know and I thought at one time I had downloaded a similar example. I think the example actually used thinking particles to simulate fire and crawl up a tree. It could probably be adapted for this use. Come to think of it aren't there some TP preset examples in the content browser that could perhaps be modified?

I had some small amount of success with a similar project using a simple deflector and setting the elasticity to zero. My falling snow was just piling up on a flat plane though, not conforming to any curves.

Taking into consideration the huge amount of single snowflakes Mother Nature is using to cover a few square inches out there I'd still prefer a mixture of particles and "growing" underlying geometry to fake this effect.

CU
Michael

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