MSFS24 MCX No glTF Albedo Texture if Complex Shader ON

[GaryGB]

Hi Arno:

MCX 1.9.2026.0512 and MCX 1.9.2026.0612 with Complex Shader ON:

Do not display color Albedo texture Materials in 3D preview for MSFS 2020 and MSFS 2024 glTFs.

With Complex Shader ON, a very dark monotone 'color' displays instead.


MCX 1.9.2026.0512 and MCX 1.9.2026.0612 with Complex Shader OFF:

Do display color Albedo texture Materials in 3D preview for MSFS 2020 and MSFS 2024 glTFs.


Is this new behavior expected if viewing 3D models in glTF format within ModelLib BGLs compiled by MSFS 2020 / MSFS 2024 SDK ?


Examples where I first noticed this:

John's CAM9 ModelLib for MSFS 2020 which is AFAIK, not KTX2 compressed DDS format exported from Blender:

https://www.fsdeveloper.com/forum/t...h-doesnt-leak-light-inside.460955/post-940736

Upon close inspection, color Albedo texture Materials in 3D preview for MSFS 2020 and MSFS 2024 glTFs are not mapped correctly when the 3D models are exported as a Khronos 2.0 (generic) glTF.

When the 3D models are exported as a Khronos 2.0 (generic) glTF and imported to Sketchup 2017, the texture Materials appear to be mapped onto numerous Group / Component 'outer surfaces', rather than individual Faces, and as a result, that apparently disables Sketchup native Right-click Menu "Texture > Position" feature to access UV mapping.

However the original BGL seems to display correctly at run time in MSFS 2020.


Keinowaara's ModelLib for MSFS 2020 which is AFAIK, KTX2 compressed DDS format via a KTX2 compressor in / exported from Blender:

MSFS 2024 Tikkurila- Vantaa - Helsinki area add-on "Tikkurila Area, Finland":

https://flightsim.to/addon/103599/tikkurila-area-finland

https://www.fsdeveloper.com/forum/t...-tiles-textures-in-blender.460965/post-940764:

Upon close inspection, color Albedo texture Materials in 3D preview for MSFS 2020 and MSFS 2024 glTFs are not mapped correctly, and the 3D models are distorted. although the BGL seems to display correctly at run time in MSFS 2024..



Thanks in advance for your clarification as to whether MCX 3D preview functionality has changed.

Also, would you please explain what we may not see in MCX 3D preview mode on MSFS glTF's ...if Complex Shader is "OFF".

GaryGB

 

[arno]

Hi,

Did you check if the model does maybe have vertex colors that are black?

 

[GaryGB]

I have not had occasion to read that MCX would display the 3D Preview in that way due to an imported object being configured with black vertex colors.

I would be glad to research that, and more specifically, I shall check the (2) ModelLibs cited above, and will report back here.

GaryGB

 

[GaryGB]

Hi Arno:

I do not see documented in MCX 1.9.2026.0612 PDF User Manual, these MCX Material Editor PBR Material Properties:

"Vertex Color Albedo Multiply"

"Vertex Color Wind Weight"


Thus far in researching this, I have found very few threads / posts which address this specific topic.

How do you expect MCX end users to distinguish whether a MSFS glTF 3D model has "vertex colors that are black" ?


Of the potentially related FSDEV threads I have found thus far, this one seems most pertinent to this inquiry:

https://www.fsdeveloper.com/forum/threads/solved-black-dark-grey-pbr-textures.455850/


IIUC, MSFS authors may overlook a Blender configuration checkbox, so a 3D model inherits this attribute.


What MCX Option(s) may we set to eliminate this needless distraction if inspecting MSFS BGLs in 3D preview ?

I do see the potential benefit of having MCX Option(s) that enable this when we want to see such attributes.

But when scanning through a ModelLib and creating thumbnails etc. this IMHO is disruptive to intended MCX tasks.

I would be glad to report back with info on the above cited files in question regarding "vertex colors that are black ".

However I would appreciate your advisement first, on how best to determine that from ex: MCX Material Properties.


Thanks in advance for your advise on how best to interpret- and configure MCX to deal with- this type of display.

GaryGB

 

[arno]

Gary,

The easiest way to see what the vertex colors of a model part are is in the hierarchy editor. It can show all vertices attributes (position, normal, texture coordinates, weights and colors). That editor also has the tool to remove vertex colors if needed.

But I tried to look at the two modellibs you linked to, but I don't see an obvious problem with them yet. Both look quite normal to me when viewed in ModelConverterX with the complex shader.. But both are quite big sceneries with many objects in there, so it would help to provide more precise information which model has an issue.

I do see that the Helsinki scenery has an issue with the textures being vertically flipped when loaded. I thought I had fixed that issue for KTX texture before.

In which editor did you find the "Vertex Color Albedo Multiply" and "Vertex Color Wind Weight" options? They don't ring a bell for me.

 

[GaryGB]

Gary,

The easiest way to see what the vertex colors of a model part are is in the hierarchy editor. It can show all vertices attributes (position, normal, texture coordinates, weights and colors). That editor also has the tool to remove vertex colors if needed.

Thanks; I shall study this for future use on personl 3D models.

To inspect 3rd party 3D models I thought MCX may add a "Disable Vertex Colors in 3D Preview" icon on a toolbar ? :scratch

But I tried to look at the two modellibs you linked to, but I don't see an obvious problem with them yet. Both look quite normal to me when viewed in ModelConverterX with the complex shader.. But both are quite big sceneries with many objects in there, so it would help to provide more precise information which model has an issue.

Keinowaara: Object #1 in the cited ModeLib BGL


IIRC, John's CAM9 "SeaAir Waiting Room" is the object in question; ronh's worked example 3D model has this info:

Name: seair_waiting_room_test_01

GUID: 48d80ecc-a3e7-4399-98e5-ff1efb53a6ef


The *.Blend file version from ronh contains only that object, and probably has John's original GUID, so that could be a quick way to find the object in John's ModelLib.

Sorry, but I am presently away from my computer with both MCX V1.9.2026.0612 installed and John's file.

But I can post an object number for the object in question from John's ModelLib later.

I do see that the Helsinki scenery has an issue with the textures being vertically flipped when loaded. I thought I had fixed that issue for KTX texture before.

NOTE: Keinowaara may have not (yet) used MCX when making his objects in Blender, and IIRC, used an external utility to generate the KTX2 format texture Materials.

In which editor did you find the "Vertex Color Albedo Multiply" and "Vertex Color Wind Weight" options? They don't ring a bell for me.

MCX 1.9.2026.0612: IIUC, these are MCX Material Editor PBR Material Properties:



Thanks again for looking into this

GaryGB

 

[arno]

To inspect 3rd party 3D models I thought MCX may add a "Disable Vertex Colors in 3D Preview" icon on a toolbar ? :scratch

I don't think that is a good idea, extra options would only add confusion. If ModelConverterX renders the object different than the simulator, I need to update the preview. But what I have seen before is that MSFS does take the vertex colors into account when rendering the textures. So that is why the preview works in this way now.

Name: seair_waiting_room_test_01

GUID: 48d80ecc-a3e7-4399-98e5-ff1efb53a6ef

I don't see a model with that name or guid in the modellib.bgl of the scenery that is linked in the thread.

NOTE: Keinowaara may have not (yet) used MCX when making his objects in Blender, and IIRC, used an external utility to generate the KTX2 format texture Materials.

I don't see why this information is relevant. For a model to be read in ModelConverterX it does not have to be created with ModelConverterX. If MSFS can render the package, ModelConverterX should also independent of the tool that was used to make it. So I'll have to check why the simulator does render it correctly, while ModelConverterX confuses about the origin.

MCX 1.9.2026.0612: IIUC, these are MCX Material Editor PBR Material Properties:

The vertex color albedo multiply and vertex color wind weight are two attributes that are for P3D v6 only (as is shown in the description of the attribute as well). So you will only see these attributes when you have set the material type to P3D PBR and not when you have it set to MSFS. Since this thread is about the MSFS preview they are irrelevant.

 

[GaryGB]

Hi Arno:

This is to follow-up on our discussion from yesterday on John's CAM9 "SeaAir Waiting Room" as the object in question.

John's W.I.P. 3D model has this info:

URL: https://www.fsdeveloper.com/forum/t...h-doesnt-leak-light-inside.460955/post-940736

Name: seair_terminal

GUID: cc867829-1bcc-4292-b011-afa41a78cde0

This info for John's W.I.P. 3D model is distinct and separate from that used by ronh in his linked example.

John's W.I.P. does show the dark 3D Preview in MCX similar to all those in the ModelLib by Keinowaara cited above.

Can MCX toggle display of vertex color via a discrete icon button (like 'night' etc.) with complex shader still ON ?

Again, thanks for looking into this.


UPDATE: Our posts crossed; I shall have to reply later.

GaryGB

 

[arno]

Name: seair_terminal
GUID: cc867829-1bcc-4292-b011-afa41a78cde0

That object is in the package John pointed to in his post. But the colours look normal to me:

Can MCX toggle display of vertex color via a discrete icon button (like 'night' etc.) with complex shader still ON ?

Let's first decide what the problem is before we start speculating about solutions. I suggested the vertex colours because these can result in dark objects, but I don't think these objects have that problem. So it might well be something else.

And as I explained above adding an extra button to toggle things is confusing and probably creates more problems than it solves.

 

[GaryGB]

Thanks for clarifying that 3D object in John's CAM9 ModelLib displays normal for you with complex shader ON.

Google reported other PBR related configurations for 3D models can also cause MCX' dark preview display.

I shall study those; perhaps later we can ID some things end users may verify in MCX' Options that causes this.


FYI: I have changed nothing in MCX' Options other than Texture paths to preview misc. Models Libs / BGLs.

Aside from that, AFAIK, MCX 1.9x is a 'default' installation on my FS development computer under Windows 10.


I simply mentioned what I saw to you, as I know you prefer to keep MCX functioning at its best for all users.

It was kind of you to reply so promptly, but I have the impression this is not a good time for you to deal with this.


If (some) Blender exports have unique PBR attributes that cause this in MCX, end users may think it is a bug in MCX.

But thankfully your screenshot above confirms MCX displays the objects in question normally on your installation.


I shall test and/or improvise ways to deal with this until I see that it is fixed by one means or another.

I have had good results overall with MCX over the years, and am confident that this will be resolved soon.


Thanks again for all you do to keep FSDEV- and your FS utilities- available to the FS Community.

GaryGB

 

[arno]

I have found the bug that caused the textures to be flipped. It only happened with BC7 compressed textures which are less common. So that will be fixed in the next development release.

As for the textures rendering too dark, if you can show a screenshot of the issue you see I might be able to explore that further.

 

[GaryGB]

Hi Arno:

Many thanks for taking another look at this; I am glad you continue to be interested in keeping MCX at its best with many FS scenarios.


Keinowaara's thread on his current MSFS project workflow, and his efforts to optimize run time performance via KTX2 format use:

https://www.fsdeveloper.com/forum/t...-tiles-textures-in-blender.460965/post-940764


I was unable to display the links to the images, as I was only able to attach the images themselves in my reply to his thread ...here:

https://www.fsdeveloper.com/forum/a...100116/?hash=8e13b3469e518981882d2147ec234b74

https://www.fsdeveloper.com/forum/a...100115/?hash=8e13b3469e518981882d2147ec234b74


John's CAM9 project imported to MCX from his W.I.P. at mega.nz is the source for my screenshots attached below this reply.

https://mega.nz/file/5Rg03BCC#pldE-rFxmvbu7Zf-GhWyPsYcE9nFB_Q8ZA1d48COmMU



PS: Regarding this incidental side discussion above in this same thread ...on PBR versus MSFS Material Properties:


GaryGB said:

"I do not see documented in MCX 1.9.2026.0612 PDF User Manual, these MCX Material Editor PBR Material Properties:

"Vertex Color Albedo Multiply"

"Vertex Color Wind Weight""


Arno said:

The vertex color albedo multiply and vertex color wind weight are two attributes that are for P3D v6 only (as is shown in the description of the attribute as well). So you will only see these attributes when you have set the material type to P3D PBR and not when you have it set to MSFS. Since this thread is about the MSFS preview they are irrelevant.


GaryGB (now) said:

I imported the ModelLib in question and this is what is displayed in MCX 1.9.2026.0612 Material Editor within Material Properties (Right-Hand Window Pane).

How is MCX displaying P3Dv6 Material Properties for MSFS 3D models, if MCX' internal "FS version Mode" is intended to toggle their display based on FS 3D model version ?


(See the 3rd image attached at the bottom of this reply to see what I see in the MCX 1.9.2026.0612 Material Editor within Material Properties)


BTW: I had mentioned that Keinowaara was processing his textures in a 3rd party texture Material utility as a "heads-up" in case it might make your troubleshooting easier.


As I read this now, I am wondering if MCX' import of a glTF may have been confused by the use of BC7 format textures. and mistakenly inferred the 3D model was P3Dv6 format ?

IIRC, you had initially been compelled to add MCX support for BC7 format textures a few years ago, when MS-Asobo implemented several new MSFS glTF texture formats ?


I am not certain as to all the options for texture output format by the 3rd party utility Keinowaara has been using, but I wonder if BC7 was used instead of the newer Khronos KTX2 ?

https://flightsim.to/addon/89937/im...for-msfs-2024-livery-creation-imagetomsfsktx2

https://github.com/theflaknine/ImageToMSFSKTX2

https://github.com/theflaknine/ImageToMSFSKTX2/releases/tag/v0.15


I try as much as possible to encourage folks to just use MCX for all their 3D model processing, especially with texture Materials.

I discourage use of 3rd party texture utilities for FS Development created / made available by well-intended authors, unless one is a highly advanced user with a very good memory.

Use of DXTBMP and other "MWG" graphics utilities for texture processing with legacy versions of FS sometimes is problematic as well; for FS2Kx, I also recommend MCX be used instead.


Please feel free to let me know if further info may be helpful to making MCX more robust when presented with these challenges.

GaryGB