How the hell...

[Jason Matthews]

I have always had a problem in Viz getting soft shadows form the daylight system. For instance,the last post in the gallery uses max. He uses a skylight. But in viz, can you do the same? I guess I just want to really utilize the daylight system in terms of indirect lighting. I use radiosity, and I have messed with all settings I know of. Any help would be awesome.

 

One more question. I hear people talking about adding dirt to the material. How exactly is that done? Using blend? Does anyone know of a tutorial?

Thanks.

[Fran]

Hi Jason,

 

If you mean the render by Juan Carlos Flores, it looks like he just used skylight and stored the direct illlumination (the default property for skylight).

 

This image is from a simple radiosity test I did awhile ago:

 

For interior scenes, I have used shadow mapped shadows and made sure that my window glass didn't cast shadows. You need a pretty big map (at least 2000 pixels) and a very small shadow bias or else you get light leaks. The further from the lightsource, the softer the shadow, so for sunlight, you can set samples to 1 and still get soft edges. The other option (depending upon how patient you are, is to have the surfaces on which your soft shadows will fall be meshed tightly (like 1" or so) and store the sunlight in the mesh for the radiosity solution. I think the mesh method is far more memory intensive.

[Jason Matthews]

If you doin't mind me asking, where is the option for stored direct illumination? I mean are we talking radiosity solution, or rendering parameters under environmaent, or what? Soory for the questions, it just that I can never get the skylight to work right without radiosity. Thanks for your time.

[Fran]

Hi Jason,

 

If you are using the Daylight System, the sunlight and skylight are combined into an Assembly. To access object properties of sun and sky individually, open the assembly and you will see Sunlight and Skylight listed in the select objects dialog. Then you can select the one you want and go into Object Properties>Radiosity. The toggle for storing direct illumination is near the bottom of the dialog. This option is available for any light in your scene. I don't recommend raytracing skylight unless you don't mind waiting a long time.

[Jason Matthews]

Hi Fran,

 

Thanks for your comments and thanks for answering my question. You have really helped me out. I am a big fan of your renderings, by the way.