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Flysimware avatar image
Flysimware suggested FlyingsCool edited

Prevent addons using default template names

There is a freeware addon called Heavy-Division/B78XH

This has over 76K downloads and any project that uses the template


will break. And that is because these developers used the exact template name in their ModelbeahviorDefs asset for their project.

And so if a MSFS customer has this mod it prefers to read this rewrite template over the default. And I get thousands of emails why our touchscreen does not work. And we have to explain to remove this addons. We contacted the new devs that took over this Heavy-Division/B78XH and they do not understand coding well and said they would fix it as I showed them how to make a custom name.

They simply need to use Heavy_GT_Interaction_NoInteraction.

@FlyingRaccoon Can we somehow fix this issue for all future headaches?

Let me know if you need more info. Today I created my own custom template to bypass this bug. But I should not have to do this. Thanks.

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bagolu avatar image
bagolu commented


I have two mods over the c172 that also use ASOBO_GT_Interaction_NoInteraction and I also have a lot of complaints because of the B78XH. The JPL/WBsim mod over the 152 is known to have the same issue too.

I agree that letting one rewrite the default templates should not be possible. it's an highway to obfuscated bugs.

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Flysimware avatar image Flysimware commented ·
@bagolu pointed out they have an experimental and I found they did stop using default template names. So this is good. But 76K downloads of the older version and incompetent devs is annoying and we need to prevent this in the future.
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bagolu avatar image bagolu Flysimware commented ·

yes, with all the people that tried the mod at one time and will keep it outdated, we can consider the Interaction_NoInteraction already dead

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Simbol avatar image
Simbol commented

Do we know the name of the MODs causing this issue guys? I am going to pin this on my discord server so people clear it.


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B21 avatar image
B21 commented

It's fundamentally flawed that a 3rd party dev can overwrite 'base' package content AT ALL and suddenly impact every other package in the sim. People are doing it just because it seems trivial to do and is frankly the easiest way to get custom behavior in your own package. E.g. the easiest way to change the Asobo html map altitude color contours is to overwrite the official mapconfig.json. There are obvious 'correct' methods to more able developers (in this case call the stock MapInstrument but in your plane point it at your own local custom mapconfig.json).

Packages are evolving ways of sharing content (like html gauges and model XML and the aircraft.cfg variation technique) and the need to overwrite stock content is highly questionable.

I should admit that my first approach was to overwrite an official file but I assumed that substitution would only apply in my package - I was shocked to notice I'd just impacted every plane in the sim and spent the hour or two necessary to restructure the code so the official files were left untouched.

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Flysimware avatar image Flysimware commented ·
But what is even worse is the dev did copy the Asobo template and placed it in their own ModelBehaviorsDef thinking this would now be ok to alter. You can do this but the name must change as the sim always looks at community first then the sim files. And I even told the guy just rename Asobo to Heavy and solved. And after 10 months they finally fixed it as an experimental and still have the main file for download. And it's at 76K downloads. The damage is done and I had to now point to my own custom template that is basically the default since now this default can never be trusted again.

Solution: Read the sim first then the addons.

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RoscoHead avatar image RoscoHead Flysimware commented ·

Won't that solution break many improvement addons that assume community files will overwrite official ones, like the Duckworks DC-3?

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B21 avatar image B21 RoscoHead commented ·

The 'overwriting stock files' method is simply too vulnerable. In the early days of MSFS a variety of people thought they could improve on the flat-panel nav instruments provided by Asobo and they ALL cheated by modifying stock files embedded deep in the Asobo solution rather than spending the time to work out the dependency structures and create a new gauge with similar dependencies on the stock content. Fortunately this Wild-West era has largely abated.

The quality solution is if you take the example of aircraft, MSFS has gradually extended it's support for one package to share the files of another so you can create a completely new 'package' that uses e.g. the model and textures and html/js instruments of another plane, while inserting your own content where necessary. I've used that to create 15m and 18m wingspan versions of the same plane - they're mostly common files (the 15m version shares a lot of content from the 18m package, but doesn't overwrite it).

This capability is important but I don't think even Asobo have fully considered its implications, and it could certainly be improved with enhancements to e.g. [VARIATION] in the aircraft.cfg.

I don't know the Duckworks DC-3 but if that doesn't give you a "new" aircraft in the sim sharing some unchanged files from the Aeroplane Heaven DC-3, but rather overwrites files such that if you load the Aeroplane Heaven DC-3 you see it modified by the Duckworks version, I'd say they could have structured their mod better. I have no doubt it's a great mod though.

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FlyingRaccoon avatar image
FlyingRaccoon commented FlyingsCool edited

Hello everyone.

This is how the VFS and Template system works and policing this is not something we want to put our foot into as there will always be ways to workaround limitations we implement and we would risk preventing fair usage of this feature.
For example, the Working Title avionics package that was available on the Marketplace and replacing default avionics was a good use of this feature that we want to keep.

Our best bet is that this was a misunderstanding and the modder didn't do it on purpose.
We're going to update the documentation to make more clear that replacing default files or templates should be used in very limited case and will impact the behaviour of other SimObjects and that copying the template is possibly a better option.


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FlyingsCool avatar image FlyingsCool commented ·

I understand your position on this, and agree there's not much anyone can do to fix this except for adding a warning about properly developing for VFS in bold letters on the front page of the SDK documentation with a link to a page with all the problems that this flexible design can cause if not used properly. There is, however, another half of this problem that is likely solveable: Developers using the default names the SDK tools suggest for items like "modellib.bgl" and "mycompany".

What happens is, multiple files with the same name end up in the same VFS path and overwrite each other. I'm sure this is the cause of many CTD's customers experience with scenery downloads as files overwrite each other, and then objects are searched for and memory overwrites happen, etc..

As I said, it's not perfect, if they keep using the same "mycompany" name and files when they change it, it's still going to cause problems, but, it's a start.

It's not a perfect solution, but, the tool should look for these default suggested names and paths and force developers to change them before it will compile the package. MSFScenery developers do this all the time. The packages work on their own, but, as soon as another package is installed also at mycompany\scenery\modellib.bgl and other files, boom. The solution of course is so simple, make a new path for each package, but, given how packages are structured, this isn't obvious to new, and sometimes even longtime, developers.

BTW, for scenery, wouldn't it be better to suggest "mycompany_airport" or "mycompany_packagename" or "mycompany_location"? That would automatically make it a new path and not matter what's inside for the most part as long as everything was contained in that.

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