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rotornut44 avatar image
rotornut44 asked FlyingRaccoon answered

Custom material generates _CVT_ / .NNZ


I have a handful of custom apron materials that I have created. I have noticed, in the last two releases or so, some of these materials will generate a legacy "myaddon_CVT_" folder containing .NNZ files. I have compared all of my .material files and cant find any structure changes between the older and newest materials in my package.

What could be causing this to happen? The materials do work fine, and as far as I know, these files are sometimes generated if someone references the material(s) in their own addon from my library package. Also, while adding a few new materials today, a CVT folder was created in my working directory as well. I haven't been able to reproduce what caused it to generate.


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Trying to gather some information before I'm able to provide a proper answer.
Where is this myaddon_CVT_ folder generated? In your package directory?

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rotornut44 avatar image rotornut44 FlyingRaccoon ♦♦ ·
I have seen it intermittently generate in both the Community folder and in Packages, the folder generated when building the package. Although, I do not think this appeared when building the package, I believe it was before. I have been trying to reproduce both cases, but have not been able to as of yet.
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OK. I had my libraries package open, messing with the material editor, but then loaded into one of my airports and opened it in the project and scenery editor. When I went to place some of my materials with the scenery editor, a myaddon_CVT_ was generated in the project Packages folder. I'm guessing because the libraries were mounted from that project directory, since I had them open previously.

I went through all of my materials, but saw that only my markings are being generated as NNZ. These were all saved in PNG8 as opposed to PNG24, so it could be a compatibility issue with PNG8 format.

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rotornut44 avatar image
rotornut44 answered

Not sure if it's related or not, but it should also be noted that I get the following error in the Material Inspector: "Material is not compatible with the current tool you are using". Although, this seems like more of a general error, maybe because an airport isn't loaded with the libraries package.

I have also noticed that the Normal Roughness Metal material option is missing from the Material Inspector now. Although, these textures are still included in my .material files. I just can't display or edit them from the inspector.

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FlyingRaccoon avatar image
FlyingRaccoon answered


Ok those files are engine intermediate files generated at runtime when you provide the game with textures not matching the expected format.
I am unable to reproduce your issue though. I created a material library using PNG8 and JPG files but all those .nnz files are generated in a cache folder located in AppData in my case.
If you are still having the issue, can you provide us with the package causing the issue so we can check what the difference is?

Thanks you,

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