FSX One Texture Needs More than One Material

Hi Arno,

I am trying a few more conversions, and one thing I am running into is that often the window glass texture is placed on a wing texture (for example). In GMAX you make *two* materials using that texture - one for the wing that is opaque, and one for the windows that is partially transparent.

Currently MCX appears to combine those materials together into one, so the windows end up opaque (can't very well have the wings transparent; they should have reflections).

I can see two approaches to solve this problem:

1. When the importer reads the MDL file, if a texture has more than one material leave them separate and in the Material Editor list more than one material with a given texture, assigned to different parts. Perhaps named like GLASS, GLASS (2), etc.
2. Make it possible to make a copy of a material and assign that material to the desired parts in the Hierarchy Editor (using a drop down box like Visibility Conditions).

If there is already a way to do this, just let me know and I'll sneak away. :)

Hope there is a solution and thanks,


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Hi Tom,

If during the import it is detected that the materials are different, MCX should already create two. Apparently in this situation it sees no difference. Do you have a test object with this problem (maybe one of the planes I already use to test)? Then I can check if some settings are not read maybe.
All the planes I've been working on so far had a separate glass texture.

I've attached an MDL file that has the situation I explained above - the glass is mapped to the dark brown horizontal rectangle on the wing_t texture, along with wing parts, etc. The wing parts are opaque, the glass semi transparent. The alpha channel of the day texture is white in that area, suggesting that transparency was only set using the opacity of the part, not in the texture itself. There is only one material created.

This plane has the added problem that the texture mapping on the cockpit glass panels shifts to another part of the texture when imported into MCX. The windows should be dark brown (on the dark brown horizontal rectangle above the vertical tails, see green outline below), but instead the mapping shifts to between the first and second vertical tails. In the image below, that is a white area with a gray vertical line in it.





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OK, I'll have a look. But I'm busy with the P3D v4.4 update now, so might take a few days.
Thanks. I realize that FS2004 models are not very popular these days, so the later sims have priority. But with P3Dv4 not compatible with Fs9 models I assume that some might like to occasionally fly the old iron. :)


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I think there is still a big need to convert old content. As you say, the more the backwards compatibility goes away, the more people want to convert.

I've run into that problem with some conversions I've done in the past. Sometimes, you can separate the glass parts using the hierarchy editor, and then set the glass as transparent. Then it's a simple matter of merging the glass back into the model, after removing the original glass of course. After doing that, you end up with multiple entries of the texture in the material editor, one transparent, the other opaque. It's a bit of a sledgehammer tactic, but it often does the trick. It does get rather messy if the glass is linked to other parts that you can't remove in MCX...


Nice workaround, thanks. I’ll try that.

If Arno can figure out what’s happening to the texture mapping that plane might be finished.

Or I can even try exporting the windows as a 3ds file, changing the mapping back in GMAX, and Merging that back into the plane (hopefully MCX won’t change the mapping again!)

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Hi all,

Just to let you know, that process did work (after more work than I expected) - thanks. It turns out that the same texture rectangle is used for anything that is dark (scoop interior, exhaust stacks, etc.) in addition to the glass. Since it appears I cannot specify transparency in a part in FSX separate from the alpha channel (see my post asking that question), if I made the alpha channel dark in that area those dark parts would start to shine with reflection (there are wing parts on that texture that also need to be reflective).

The windows were combined with other parts after FSX conversion, so I had to start over with the FS9 model, remove the windows, fix all the rest of the stuff, I had to do before, and then Export to FSX format. Then merge in the slow and blurred, props, and fix all the materials for reflection, transparency, and night lighting.

Since I had to remap the isolated cockpit windows anyway (due to the odd texture mapping shift that occurs when you import this plane into MCX, see post #3 above) I took the opportunity to move the mapping in GMAX to a tiny little part of the dark rectangle not used for any dark parts. Then I could edit the alpha channel to make it dark only in that small area.

The result is that the glass is now transparent (and I used Bill Leaming's glass material settings to make it look like glass), the dark parts are still dark, and the wing/cowl parts on that texture still have reflection. Whew!
Ouch! Been there, done that! Glad you got it all sorted. It always feels great when something like this works out.

Sometimes you can get away with simply assigning a new texture to the part after you've removed it - and then simply ignore the fact that on the original it was part of a shared texture. I should have mentioned I usually start with the FS9 model for the part isolation... it's just a habit of mine, but reading what you went through I now know I've been lucky...

Yes, a new texture would have been a good choice - I should have thought of that...

Luckily I saved MDL backups throughout this process and can do that relatively easily. :)

Thanks for the tip,