Framed glass in UDK mixing solid and translucent.

[westmeadow]

Hey everybody,

I have done a search for this and found similar topics and read the differences here, but I was looking for advice on how you'd approach this.

I'm looking to create a sloping roof section like in the image shown below. I want the metal sections (in red) to block light coming in from above (even creating shadows if possible); but receive light from inside of the room aswell.

I'd also like the glass sections (in green) to be translucent; allowing light in from above, receiving light for specular and normal purposes but not bounce light as if it was solid.

I was looking to do this using a single plane static mesh for each section, but as far as I'm aware, the material applied can only be either masked (which wont work for my translucent glass) or translucent (which, with a solid mask for the frame, could work?). But then does it have to be Unlit... especially if looking to also apply distortion.

Am I better off doing this with 2 seperate meshes and 2 textures? How would you approach this?

I hope I have made this clear

Thanks everyone.



Arron

[mmcleo11]

You can do this by 1 mesh with 2 different materials applied in your 3d app then on import to UDK set up 2 materials: 1 for the glass n the other for the frame

[westmeadow]

Thanks for the response mmcleo11,

Would this mean adding more geometry to the plane to apply material IDs to individual polys? At the minute, this is simply a single plane.

Thanks again

[Benjammin]

Yes, add more polys and separate the materials based on the IDs. Translucency is expensive and notorious for rendering artifacts - only use it where you absolutely have to.

[mmcleo11]

Well alphas tend to be expensive but there are occasions where you have to use them.

You are going down the right path making the material UNLIT. And yes you will have to cut the polys where the glass panes will be.

Sometimes Ive found some artefacts in UDK when using a normal map esp if there is any gradients i.e. soft edges around the poly that is the glass. I can explain it a little better as that may seem confusing lol

[westmeadow]

Guys, this is all great advice, thanks alot. Looks like I'll add geometry to the plane. It'll be more expensive but will work so much nicer.

Thanks again,

Arron

[mmcleo11]

The expense is worth it as the only other way to do it is using a specular power and opacity maps, which increases your texture budget and also the shader required to let you do the glass and the frame material will be pretty expensive.

Polys are usually are usually a cheaper option than more textures for example. Plus you will get much nice shadow and occulsion by using more polys