Alpha-texture dificulties.

[Stavaas]

Hey there,

I'm a modeler on the Nehrim team, and we're having some difficulties getting an alpha-texture on a model I've made to work ingame.

 

This is what It's supposed to look like:

http://i302.photobucket.com/albums/nn103/Stavaas/scarecrowrender-1.png

 

And this is what we get:

http://i302.photobucket.com/albums/nn103/Stavaas/Alpha1.jpg

 

As you can see, the alpha-texture isn't working, and we can't find any tutorials on how to get it working either.

 

I really hope someone can shed some light on this subject, as I'd hate to have to sack this model.

 

-Stavaas

[Vagrant0]

First, alphas don't always show in nifscope, even when the settings are right. This is most often the case when you have alot of parts with alphas on them. But you still need to make sure that there is an alpha property attached to the nitristrips in nifscope. You might want to look over some of the tutorials for nifscope if you aren't too familiar.

http://cs.elderscrolls.com/constwiki/index...101_:_Basic_Use

 

Basically, you need to insert an alpha property somewhere within the ninode, then attach that property to a specific nitrishape/nitristrips by adding another property listing. Multiple meshes can use the same alpha property.

[Stavaas]

Yeah, I've been looking all over the Elderscrolls WIKI you've linked to, but I can't find anything to help me much. I've attached an alpha property to the nitrishape, and I can get the straws to be completely transparent, but I'm unable to get just the black around the straws to become transparent, leaving the straws completely visible.

 

Any ideas what I'm doing wrong, or not doing at all?

[LHammonds]

If you are adding the NiAlphaProperty to the appropriate NiTriStrips and setting the value to 4845, then your problem is most likely in the Alpha channel of your diffuse texture.

 

White in the alpha is 100% opaque, 0% transparent.

Grey in the alpha is 50% opaque, 50% transparent.

Black in the alpha is 0% opaque, 100% transparent.

 

If I have the colors backwards, just inverse it to fix...90% certain, 10% forgetful / old.

 

LHammonds

[Stavaas]

Sorry for my late reply. Yeah, I know that white is 100% opaque and black is 100% transparent, so I haven't gotten the colors wrong. We managed to get the alpha working in the NIF editor, and ingame, but I'm not happy with it yet.

 

http://i302.photobucket.com/albums/nn103/Stavaas/Vogelscheucheas.jpg

http://i302.photobucket.com/albums/nn103/Stavaas/ScreenShot437.jpg

 

As you can see in the images, the transparent black, which is completely invisible, blocks the straws behind it. And it also looks like it is glowing, even though it should be pretty matte.

 

Any ideas how to fix this? I really don't think we're stuck with them looking like this.

[Vagrant0]

It's how alphas work within the engine. the only real solution is to save it with a pure black/white alpha (no grayscale) and save it as DXT1 1 bit alpha. But some resolution of the straw will be lost.

[Stavaas]

Really? So there is no way to fix it then?

[Vagrant0]

Really? So there is no way to fix it then?

 

It's how alphas work within the engine. the only real solution is to save it with a pure black/white alpha (no grayscale) and save it as DXT1 1 bit alpha. But some resolution of the straw will be lost.

That ^^^^^^^^^^ is the only solution short of making each piece of straw a small sliver like polygon, or using a single layer of transparency. As the method quoted requires the least effort, and no change to the mesh, it might be a good place to start. You can combat any resolution loss just by making the base texture larger.

[jaysus]

you could always try to make the alpha channel plain black and white (NO GRAY!)... the straw wont be see through anymore but you get rid of that glow and if youre alpha texture is well made it shouldnt matter...

also make sure you dont have a glow map or a normal map with reflection for the texture

 

as for the black-invisible part blocking the background thats strange indeed... its not that way with leaves or grass either... maybe check these two and look for differences