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Piata

09-26-2003, 12:11 AM

The problem: my falling snow is gray/black and I want it pure white. I've tried making the material self illuminated but self illumination doesn't seem to work with radiosity. I've tried looking through help files and on the net for a solution to my problem but can't find one.

Is there a work around for this? or am I just missing something?

I'm using IES Sun at 90,000 lx and automatic exposure control (I've tried logarithmic exposure control as well with similar results).

Can anyone help me?

Dave Black

09-26-2003, 03:04 AM

Select the snow.

Right-click --> properties.

Look at the tabs at the top of the dialog. Click the advanced lighting tab. Use the exclude from advanced lighting option to make the snow not be affected by the radiosity calc.

Hope that helps!

-3DZ

:D

Aldaryn

09-26-2003, 06:33 AM

Do you really need radiosity to do this image? IMO Light Tracer would be better outdoors...
But, the Snow should be illuminated not onl yby the sun, but the sky also. So try creating an IES Sky also. This will add a quite homogene "ambient" like light over your scene, and IMO it will make balck snow disappear..
Also, using denser mesh in the radiosity calculation could even bring more light to your snowflakes.
But I still say you should use Light Tracer for outdoors.
Oh, and Self illumination is affected by radiosity. In the demo file for Radiosity, the neons are created with self illumination, and some lighting override. (This is a special shader, that you can apply over an existing shader...)

By the way, if you use Radiosity, be sure to use log exposure control, due to high lux levels.

Good Luck!

- A.

Piata

09-27-2003, 09:53 PM

thanks for the help. I tried using light tracer but the render times were a little brutal for my 1.3Ghz tbird (unless I configured something wrong). So I'm going with plain old omni lights, area shadow maps and brazil for now. Project is due wednesday and I can't get hung up on lighting :)

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