P3D v4 Transparency.... again!.... (Transparent objects behind other Transparent Objects)


Resource contributor

In the image above, the foreground object is glass on a bridge to a jetway. The background object consists of a fully opaque glass material and a partly transparent material for the terminal walls. As you can see any transparent material behind the bridge glass disappears.

Funny thing is, this identical material is used on an SODE jetway model for its glass and it does not make any materials behind it disappear.
See this image below where I removed everything from the Jetway model except the glass.

The ONLY difference is the jetway is an .mdl placed with SODE and the bridge glass is part of the terminal model placed with MCX. All material settings are perfectly identical.

I cannot figure out why one works properly and the other does not.
If I place the jetway model using MCX it works correctly, but if I merge the jetway glass into the terminal model it stops working even though no material settings have changed.

I have tried everything, but I'll attempt to list them below.

  • Separated the bridge glass into a different model
  • Turned on/off Z-write, Z-test, Z-alpha, threshold, Double-sided, Set Default Transparent, etc,
  • attempted to export new bridge glass from 3DS Max just as I did for the jetway
  • Change model and texture names to affect drawing order
  • Changed reference location to affect drawing order.
  • Changed the names of the textures used by jetway glass and bridge glass.
  • A whole lot of other things that I can't currently remember....
Please find attached the bgls and respective textures.
I'd appreciate if anybody could take a look and tell me what I may be missing.



Resource contributor
Well I guess everyone's as clueless as I am.

I managed to get it fixed, partially.

While re-positioning the geometry slightly and re-exporting it (with what I believe are the same material settings) the problem fixed itself, except, everything that is inside of the Jetway bridge becomes translucent when viewed through the glass, as below on the right half of the image.


I've kinda spent the last week pulling my hair out over this, but I think I've decided to just accept it as its only apparent from certain high angles and up close.

Short of rebuilding and re-exporting the entire scene, I'm clueless as to what will fix this. And this project is beginning to get fatiguing, so that's a no.


Resource contributor
Just came back to say that I noticed the problem was no longer present a few weeks later. I have not re-textured/re-built/re-exported anything.
SO weird.
Does anybody know if P3D rebuilds its shaders every now and then? That's the only thing I can think of to explain this.