Shadows where there shouldn't be

[automan25]

Take a look at the attached picture. I have a light set up to shine in through the window. At this point it is just a test to try and rectify the problem I'm having with this scene. In this model of my house all of the normals are facing inward, hence the reason you are able to see into the house.

In such a case I should be able shine a light onto the model and have it light up the interior polys, correct? When I render this image, however, this doesn't happen. The light is completely blocked as though the polys were double-sided. When I turn off shadowing on the light, then the polys do light up.

What is going on here?

[JulianW]

Hi,

as I recall LW renders shadows based on passing through polygons from the back side to the front side. Hence no light will get in as you seem to have window polygons in the room (facing inwards).

I'd check that is the problem by deleting the window polys and doing a test render first. Once your sure it is you can easily split the windows into a new layer and set the layer properties in Layout to disable "Cast Shadow".

hope that helps,


JW.

[Dodgy]

Are you using Shadow mapped lights? Shadow maps don't pass through transparencies. In which case change them to ray trace and they will go through any transparencies (like windows should be) or do as Julian says as LW casts shadows from any polys WHICH face away from the camera. Cut the windows to another layer and turn this layer's shadow casting properties off :)

[tonsofpcs]

Couldn't you just set transparancy/translucency/radiosity/refractivity/etc on the window textures to have them pass light as normal windows?

[Dodgy]

Not if he's using shadow mapped spotlights. These don't penetrate transparent objects...