[3DSmax] Texture border is transparent, why?

Mr_Drayton

Hi everyone!
There's an issue I get everytime I add an Alpha Map to my textures. Look at this image...



This is a simple lowpoly model, I just began to texture it. The yellow thing is a jet engine, and the black ones are some metal bars that cover the big air intake. Between the bars, the texture is transparent and makes part of the inner geometry visible.
But, when I add the Opacity Map and activate it to be visible in the viewport, some other parts get transparent, as you can see... That parts are the top row and the right border of pixels on the texture map. I just don't figure why... Is there some way to fix it?

PS: Hope I explained it well...

Michael Knubben

If I'm seeing your image correctly (and it has to be said, it's not very clear), that would be caused by alpha-sorting. Max sorts alphas in order of creation, which makes it nearly impossible to get nice alpha-sorting in the viewport. Just ignore it and make sure your alphas sort correctly in whatever engine you're exporting to, which will have a different method of deciding what goes in front of what.

Mark Dygert

Render it, if it looks fine then you should probably just deal with it as is in the viewport. If it still looks jacked up it's probably you're unwrap, or the opacity map.

How did you set up the material what does the unwrap look like, and what does your opacity look like?

Mr_Drayton

Yes, that wasn't so clear... Let's try again (with more of the texture done)!



The wireframe should help. It's like there is a 1 pixel thick transparent border on my texture... On every side! Anyway, the render is just fine, so I suppose there's nothing really wrong. Sincerely, the entire thing is not a problem, but just a matter of seeing everything well in the viewport!

The material is simply a Standard Map with Self-Illumination set up to 100, a Diffuse Map and an Alpha Map. The Alpha Map settings are:
-Filtering: None
-Mono Channel Output: Alpha
-RGB Channel Output: RGB
-Alpha Source: Image Alpha
-Premultiplied Alpha not selected

Mark Dygert

Yep, that's the old viewport transparency issue. There's a way to make it disappear, something with a tiling setting... man its been a while. Maybe you need to pull the opacity map out of the alpha and set it up as its own map, just for this.

As long as it renders ok, transparencies in the viewport have always been a bit dodgy. Transparencies are always a bit tricky even in various engines.

Mr_Drayton

Thanks for the help! I'll just continue working as I always did. This issue it's not annoying at all.
I remember we talked about transparency overlap in another topic I started... Anyway this one is an Alpha-Test case, and not Alpha-Sort, so it will be just fine.

Man, I think I will be famous here as the man who had problems seeing through poligons. :P

Ghostscape

don't use .bmps, use .tgas, and I believe that fixes the issue. This issue has existed forever in max and its because it chokes on certain image file formats with alpha.

Mark Dygert

I also remember it having problems sorting transparencies on the same object. If you break the transparent piece off and apply a copy of the material without the opacity map to the rest of it, it would probably sort ok and get rid of the boarder.

Ghostscape

Vig wrote: »

I also remember it having problems sorting transparencies on the same object. If you break the transparent piece off and apply a copy of the material without the opacity map to the rest of it, it would probably sort ok and get rid of the boarder.

It's not a sort issue, it has to do with certain file types being read incorrectly by Max, which gives you a nice 1px alpha border around your texture, which means things that bump up against the edge of your UVs get that wonderful alpha edge.

Your fix is good for alpha sorting issues, but look at the bottom of his hovercraft in his wireframe shot.

Like I said, try different file formats (I believe it reads .tga correctly), or you can also break your alpha out as a separate black and white alpha map for the purposes of viewport display.

Max is just retarded at reading alpha channels in certain file formats.