UDK Alpha Shadows not being built

KingUNREAL

Hi everyone, as the title says I'm having a problem with alpha shadows not being built on to my ground mesh. After doing a bit of searching through the internet I couldn't find any fixes.



Moving the meshes would produce a great shadow, but building lights would remove it.



When I started the default placeholder scene, the alphas would build somewhat properly on to the ground box though.



So that lead me to believe it's something wrong with my ground mesh.
For reference it has a 2nd uv channel for lightmaps and I'm using UDK July.

Any help will be greatly appreciated, thanks!

Santewi

If I recall, that is a bug in the July version of UDK. Have you tried other versions?

robert.briscoe

July UDK does indeed have issues with static meshes casting masked shadows, have you tried updating to the latest version of UDK? (Feb 2013)

KingUNREAL

I had tried November (February wasn't out at the time) and I still had this issue. I will download February and update with my findings though, thanks.

*Edit* Tried it in February UDK, still no built alpha shadows on my original scene. But when I started a new level and just placed a couple things and built, I got these shadows.

Xendance

Are you sure that the ground just doesn't have a too low res lightmap for visible baked shadows?
Could you post a screenshot of the lightmap texel density view mode?

KingUNREAL

Here's a screenshot of the ground meshes properties.



Lighting with Texel Density


Lightmap Density

Froyok

Regarding your ground, I would try something like 1024 for the lightmap, you don't have enough texels to get the details you want.

Xendance

Yeah, it's too low res. You want to use real-time shadows in cases like this, look up the cascaded shadow mapping settings for the dominant directional lights. It allows you to blend static shadows into real-time shadows when the shadows are close to the viewer.

KingUNREAL

@Froyok - Thank you, I feel that brought my shadows out a bit more




@Xendance - Alright thanks, I'll definitely look into that!