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View Full Version : How do you get soft Shadows when Raytracing?


Sardo Numspa
07-04-2003, 08:53 PM
This is a scene I have been working on. Notice the hard shadows underneath the cars. How do I soften these up? They are ray traced...not Dmaps. Any other suggestions welcomed and how to improve this scene and look. Thanks.

BTW...I would use Dmaps but the shadows are hosed. I have adjusted the Res to match the render output i.e. 640 x 480. So I raytrace.

NitroLiq
07-04-2003, 09:28 PM
You want to look at both the light radius and shadow rays attributes. In a nutshell, adjusting the light radius will give you your soft shadows. The Shadow rays attribute controls the sampling of the shadows (kind of like the dmap filter).

NitroLiq
07-04-2003, 09:48 PM
Btw, here's a quick example I just did for you with a sphere, ground plane (a cube actually) and a spotlight. I left the raytracing defaults in render globals and in the spotlight's attributes, it's setup like this:

no decay
cone angle 40
penumbra 10
dropoff: 0


raytraced shadows on:

Light radius: 2.009
shadow rays: 10
depth limit: 1

You should experiment with lower values....increasing radius or rays will slow your rendering, even for simple scene such as the one I did.

NitroLiq
07-04-2003, 09:49 PM
Ewps, forgot the attachment (hit the wrong button). Here it is.

Sardo Numspa
07-04-2003, 11:00 PM
Thank you for the advice and example. However, I am using 4 directional lights so what are the parameters for soft shadows with them. Thanks.

NitroLiq
07-04-2003, 11:41 PM
Directional lights have the same raytrace shadow attributes as the spotlights. Adjust the same settings I mentioned.

NitroLiq
07-04-2003, 11:47 PM
Here's another example using the same settings as before except this has a directional light rather than a spotlight.

Sardo Numspa
10-04-2003, 12:57 AM
Thanks man. I got it to work. I have a new problem now so check for my next posting.

Cheers

M
10-04-2003, 05:57 AM
Hey, i really like your render there, thats a great scene... i would definately tone down the lighting a bit though, it makes it look a bit fake because it shows ALL the details with that much light, the less light, can sometimes be the best thing :). Really nice though, post your fixed image when its done :).