View Full Version : Shadows Move?

12-05-2004, 08:37 PM
Can someone explain why my shadows move away from the object base like they do? to be more specific the cactus.

Here are my settings for the spot light

Spot cone angle - 30%
Soft edge - 5%

shadow map 3000
shadow fuzz - 10.0
Radiocity enabled 1x3 1 bounce

I'm using a textured displacement map for the Land object and sas lite for the weeds

Thanks all Shane
Click here to view (http://www.sugnadesign.com/clients/crowncouncil/2005event/desertdemo.htm)

12-05-2004, 08:57 PM
It looks like your front catus is not setting on the ground, as the shadow should be touching the catus. I beleive light is shining below the catus.

12-05-2004, 09:58 PM
Shadow maps are not as accurate as ray tracing. I agree with Silkrooster it is most likely just object positioning. I have not run into this problem with Lightwave (ever) but sometime in Blender a shadow map will not reach the base perfectly. Quick test, see if turning on ray-tracing will fix the problem. If it does not then your object is not touching the ground.

12-06-2004, 01:14 AM
Thanks for your replys.

The cactus are positioned correctly under the ground. I'm using a Displacement Map to warp a flat plain into the rolling hills. Could that be the problem?

Is there any other way of making soft edge shadows with a ray tracing light?


12-06-2004, 01:22 AM
The displacement map should not cause a problem, unless it’s moved the ground away from your cactus, that’s what happened to me when I tried to recreate your scene. I take it that ray-tracing fixed the problem. Is there any way you can upload part of your scene so I can take a look at it?

12-06-2004, 02:17 AM
all wrong, the smoothing made by the displacement map IS the problem with shadow maps... why, coz they dont see the smoothing, and are casting shadows based on the real polys position... the only way I know to cure this is to use an area light...

12-06-2004, 03:14 AM
Hey Hervé does that mean that the problem is with the displacement map, or just using shadow maps across uneven geometry? More spacificly, Could the geometry be frozen to fix the problem or is it just an issue of the shadow map reading poly edges only.

12-06-2004, 03:18 AM
yes indeed polys edges.... so the solution might be to subdivide it in Modeler (different try & errors for the number of subdivisions..), freezing it... and work from there.... tell me if that worked.... otherwise area lights works for sure.... :cool: