Missing Glass

[J G 927]

I have just completed installing a livery to X-Plane and I have discovered a problem with the textures I am using.

The cockpit glass is missing.

Below is the default aircraft:

My repaint:

The image file is a DXT 1 Bitmap. Note that this image is clear where the canopy is, inline with the black on the Alpha Chanel below (I guess that this is a jpg limitation):

with an Alpha Channel as below:

Can anyone help?

 

Edited January 7, 2019 by J G

[dodgy-alan 1,587]

You have the British spec version, the MOD elected to save money by ordering the open cockpit option! They generally come without wheels and tailpipes as well! Our government are nothing if not cheapskates! 

[needles 1,010]

Hi John,

I'm not sure about this but try inverting the Alpha channel and see what that does to the glass.

As I say, I'm not wholly sure but it might be worth a shot.

Cheers

Brian

[Soaranden 84]

Using DXT3 or DXT5 should provide the desired semi-transparancy, John. Although I have not developed anything for X-Plane, I expect the rules regarding DXT textures are the same in both FSX and X-Plane. Here is an excerpt from the FSDeveloper Wiki regarding DXT1 versus DXT3 in FSX:

In Flight Simulator there are two different texture formats, the DXT1 and DXT3 texture. The DXT1 texture has a 1-bit alpha channel, while the DXT3 texture has a 4-bit alpha channel.

This means the DXT1 alpha channel can only contain 2 color, black and white. All parts that have a black color in the alpha channel will become fully transparant, while all parts with a white color in the alpha channel will show as normal. This format can thus not be used to make parts semi-transparant.

In a DXT3 texture you can use up to 16 colors in the alpha channel, so you can also use different tones of grey. These tones of grey allow you to set parts as semi-transparant. The darker the grey color is, the more transparant it will become. Due to the larger size of the alpha channel, the size of the total texture is also bigger in the DXT3 format, so only use this format if you really need semi-transparancy.

To read the full article see: Alpha channel creation with Photoshop

I hope this helps.

ADDITIONAL RESOURCES

Here are a couple of additional resources from the FSDeveloper Wiki. Again, I'm making the assumption that this information is applicable to X-Plane, too:

DXT compression explained

Texture formats overview

Finally, and importantly, here is an X-Plane-specific article regarding Texture Compression

The article shows the preceding FSX DXT texture information is equally applicable to X-Plane.

Edited January 8, 2019 by Soaranden
Additional Resources

[J G 927]

Thanks Soaranden you have solved the issue, that was a very helpful and instructional reply.

Could I please ask you another question?

I have seen liveries that are matt and some that are very shiny.  How do you control the reflectivity of a surface? 

[Soaranden 84]

According to a search I did, your question about controlling reflectivity gets into an area where X-Plane 11 does differ from FSX. About the best I can do is to provide a few links that may lead you to the desired reflectivity control:

How to create Chrome/BareMetal look/texture in X-Plane 11

X-Plane 11 Material Model

Modeling Documentation

Edited January 9, 2019 by Soaranden
Added Modeling Documentation link