build lighting and grass :(

ultramedia

Hi Everyone,

I have a problem with a workflow I'm trying to lock down for lots of luscious grass in UDK.

Here's my grass before I build lighting:


Here's my grass after I build lighting


I've tried everything I can think off, but can seem to figure out how to exclude the grass foliage instances from having the static lighting applied to them...

Any suggestions?

sprunghunt

ultramedia wrote: »

Hi Everyone,

I have a problem with a workflow I'm trying to lock down for lots of luscious grass in UDK.

Here's my grass before I build lighting:

Here's my grass after I build lighting

I've tried everything I can think off, but can seem to figure out how to exclude the grass foliage instances from having the static lighting applied to them...

Any suggestions?

Did you try excluding the grass from the static lighting channel?

another thing you could try is to give the grass a shader which replaces the standard lighting model with something that uses the world up vector instead of the normals.

or you could hand edit the normals. Like you would for a tree.

Jessica Dinh

Also fwiw, on small ground objects like flowers and grass I usually tweak the vertex normals so that the normals are facing more upward, that way they get more light. Otherwise when you put them on the terrain they'll clash with the floor because they'll be lit wrong.

If you're using 3DS Max just apply the edit normals modifier to your editable poly then grab the blue sticks and rotate them so that they're facing more upward (probably dont want them to be straight up tho). Make sure you've got a light source in the scene so you can tell what's going on.

That's something I've been told recently. Not sure if that's your issue, but can't hurt to give it a try!

ultramedia

Thanks everyone, very fast and very good replies.

Sprunghunt, I can see lighting channels in the properties of a static mesh instance when I drag it into the viewport, but when I use the foliage to paint my grass mesh there is only the foliage actor in the scene and the static mesh in the content browser neither of which have any reference to lighting channels in their properties. Is there some other location where you can control the relationship between foliage meshes and lighting channels that I just don' know about?

Jessica, I'm using Blender 3D, but it should be no problem to adjust the normals. I get the feeling your suggestion is going to be the one that solves my problem but I won't be able to test it until I get home tonight after work - and I'll be fidgeting impatiently all day waiting for work to finish so I can see

ultramedia

Hmmm... can't configure normals as easily in Blender as in Max...

Trying a different approach:
- 1.0 into transmission mask
- hook texture up to emissive as well...

Seems to be doing the trick, won't know for sure until I get home and test on my large landscape scene (work puter has no SM3 card).

Leodido

hey, just wanted to ask, how did you make your grass? I'm working on a game map for RO2 and need some grass.

ultramedia

I've got a huge tute 90% made to put on my website, that show's how to replicate this from start to finish, I just can't get this stupid last bit right with the build lighting stuff (grrr)

ultramedia

Yay, figured out how to exclude the foliage grass from static lighting...
Just set the light map resolution inside the static mesh to zero

Now I got nice lit grass - it even sinks into the ground in the distance.

I'm doing a series of video tutes covering all this, but I might talk about them in a new thread.

WarrenM

Well, that won't remove it from the static lighting but rather it will switch it to using vertex lighting instead. But if it looks the way you want it to, so be it.

Leodido

oh awesome, I'd be very interested in this tutorial, could you post the new thread here when you know it. thx