Ut3 - Shadows through an Alpha Plane

Cody

I'm sure this is answered somewhere on the forums, but I can't find it, or with a google search. <-Fail. The shadows shining through a grate alpha plane are just looking like there isn't an alpha on the object at all. My material is set up as masked and everything. Help?

Peris

only works with realtime shadows, baked lighting just ignores your alphas .

Cody

grrr...

gamedev

Yea, its not doing any raytracing for that stuff. Try a light function if you want the shadow from the grate on the floor.

PixelMasher

oh i had this problem a while back while trying to get shadows from alpha plants to work properly. static meshes cant cast alpha shadows.

you have to make the object an InterpActor and tick enabled and CompositeDynamic shadows on in the light environment channels. and it should take the alpha into consideration.

instead of right clicking and going to add actor:static mesh go to add actor : interpActor.

hope these images explain.

00Zero

pixelmasher, i tried this. dont you have to set your light to cast composite shadows as well? if you do that, doesnt it make the light dynamic? it did for me anyway, and i couldnt get any shadow bakes out of it.

PixelMasher

Ah yea sorry you have to turn on composite in the lights lighting channel as well.

When ever Ive used them Its been in conjunction with a directional light (static and dynamic) simulating the sun so yes they are dynamic shadows not baked but they don't have the razor sharp edge or intense blackness of stencil shadows, I just find the results nicer.

as far as I know you will never get something with alpha to cast a proper shadow using only static lights, like Peris said. I dont know if thats a problem for you or not Cody, but let us know how you end up getting your desired result dude.
cheers

Cody

Thanks for the tips guys, I'll try it out and let you know.