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G91-R: Combining incompatible licences in a single aircraft.

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Re: G91-R: Combining incompatible licences in a single aircr

Postby abassign » Sun May 29, 2016 4:29 pm

Image

erik wrote in Sun May 29, 2016 1:55 pm:... See, start from scratch and there is no problem. :)
Erik


:) Yes Erik this project born from scratch in the 2014 in May ... June from my request in FaceBook Flightgear Italia forum https://www.facebook.com/flightgearitalia/ in this forum a work as moderator with other FGFS fans.
Our blog in Italian is read by more than 240 fans mostly come from experience with FSX and X-Plane. Therefore, to keep the interest I have always taken care of the quality of aircraft and scenarios.
If I insert an article on something that is not as visual quality comparable to FSX or X-Plane, the approval rating drops considerably and constantly risk losing people interested in trying FGFS.

The 90% of blog readers do not know the difference between a Freeware (common license in aircraft issued with no surcharge in the X-Plane) and a GPL or Creative Commons!

Many readers were attracted by the quality of FGFs (about many programmers and enthusiasts FGFs) and asked me to promote Italian planes in the FGFs are few and average low quality both in 3D and FDM. At this point it seemed right to promote something that could meet the tastes of our fans and also my;). I then started looking for a good 3D modeler that could make the G91 with a quality close, if not superior, to aircraft sold (or issued with license Freeware) in FSX or X-Plane. Cobe571 has accepted the challenge of making a 3D quality, but he is a professional 3D modeler! He did not ask for money, but just to be able to keep part of the intellectual property that is well specified by creative common license he has chosen.
I am a computer consultant and so I have a different view, and so I chose the product of my work is licensed under the GPL (GPL software I only use at home or at work, for my explicit choice).
In these months I realized one very important thing that programmers (race to which I belong), and professional 3D modelers have different requirements because they operate in different sectors. This is the reason why excellent aircraft for X-Plane and FSX products by enthusiastic groups have a Freeware style license.
Unfortunately, the Freeware license, does not allow to modify the aircraft code and therefore can be very beautiful in 3D, but far enough stupid in the flight behavior.
We are therefore on the opposite side, very beautiful aircraft, but flying qualities and other rather childish.
FGFs can then play a winning game if, together with the great programmers working on various projects, it allows 3D modellers enthusiasts present their work, then following their rules, which are different from the rules of the programmers.
Therefore there is the necessity of opening a mixed regime of rules, which allow, on the one hand to preserve the greater wealth of FGFS, ie the open code, this is for the execution of the kernel and, for airplanes, but at the same time, for who considers it necessary, to preserve the right to "possession" of the modeling work.
Obviously this does not mean that something will change in the ecology of the system, simply enriches the offer that FGFS makes to his fans.

This is why I felt it was possible to give this possibility by placing a repository with Creative Commons license type CC-BY-NC-ND 3.0 or better CC-BY-NC-ND 4.0. For example GitHub permits this. Such as GitHub to allow such license as it is listed: http://spdx.org/licenses/ as cited in this note: https://github.com/github/choosealicense.com#license-metadata So technically it is possible to have a repository "official" nofree, which are allowed only a limited number of CC licenses, mainly the CC-BY-NC-ND 4.0 really like 3D modelers.


To gain access to an "object" with this particular license contained in a suitable repository you can change, as already mentioned a few posts ago, the XML file upload, for example as follows:

Code: Select all
   <model>
        <path license="CC-BY-NC-ND 4.0" cache="YES" >Aircraft/Fiat-G91-Series/Models/G91R4.xml</path>
   </model>


With this syntax, the system will download the file from the repository, where the files are included with that particular license. This approach avoids the imaginative use of path which could make life difficult enthusiast who wants to fly in an airplane. As you can understand the code that invokes the file is only present in the official repository that is under the GPL and retrieves a file with a different license, with a completely legal approach, normally used by all operating systems under the GNU license (non-free repository).
If I, who have Linux with GNU license, I want to see a MPEG movie, I MUST download a licensed program that is not GNU, because MPEG has a different license !!!
And this, perhaps without knowing it, you do it all ... every day ;) Why can not we do it with Fgfs ?
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Thorsten » Sun May 29, 2016 5:18 pm

Therefore there is the necessity of opening a mixed regime of rules, which allow, on the one hand to preserve the greater wealth of FGFS, ie the open code, this is for the execution of the kernel and, for airplanes, but at the same time, for who considers it necessary, to preserve the right to "possession" of the modeling work.


Yes - what about my right to 'possession' of the coding work? I feel that if it's okay that you can modify my code, I should be able to modify your 3d model if I need to. End of story.

Are you saying the 3d modeling skill is so much more valuable than the coding skill so that we should allow one group to opt out of the project structure? I'm not interested in such a scheme.


With this syntax, the system will download the file from the repository, where the files are included with that particular license.


The GPL FAQ says effectively no:

The difference between this and “incorporating” the GPL-covered software is partly a matter of substance and partly form. The substantive part is this: if the two programs are combined so that they become effectively two parts of one program, then you can't treat them as two separate programs. So the GPL has to cover the whole thing.

If the two programs remain well separated, like the compiler and the kernel, or like an editor and a shell, then you can treat them as two separate programs—but you have to do it properly. The issue is simply one of form: how you describe what you are doing.


http://www.gnu.org/licenses/gpl-faq.htm ... tarySystem

An automatic xml tag is a pretty efficient way to hide what you're doing, not to describe what you're doing. Also, the 'two parts of one program can't be treated as two separate programs' is not so clear-cut.
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Re: G91-R: Combining incompatible licences in a single aircr

Postby helijah » Sun May 29, 2016 5:54 pm

I absolutely against this the. And I would put all my cométences and all my weight for that to not happen. FGFS is GPL and must remain GPL. All other licenses are preparations for the creation of an FGFS owner. It's totally and definitely against the spirit of open source.

I am not always in agreement with the current managers, but this time I am :)

Regards Emmanuel
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Re: G91-R: Combining incompatible licences in a single aircr

Postby abassign » Sun May 29, 2016 6:32 pm

helijah wrote in Sun May 29, 2016 5:54 pm:I absolutely against this the. And I would put all my cométences and all my weight for that to not happen. FGFS is GPL and must remain GPL. All other licenses are preparations for the creation of an FGFS owner. It's totally and definitely against the spirit of open source.
I am not always in agreement with the current managers, but this time I am :)
Regards Emmanuel


No problem, but one thing is Fgfs (container) and one thing is its content.
If you do not want to use content with a CC license, no problem you're free to do so.
No problem if you use GIMP (which is a GNU standard) you can also edit images with CC, respecting the rights that gives you the license ...
No problem if you are using GNU Linux and with it, listen to music with a CC license and maybe in mpeg format (mpeg is not GNU) ...
No problem if you use FaceBook ... but remember that his license the same content that you enter them is certain GNU not and is not owned by you ...
I have to go on , with other examples?
One thing is the container one thing is the content, is one of the fundamental paradigms of Informatics :)

The important thing, as rightly noted Thorsen, it is to keep things separate, if I produce the GNU license code for FGFS, I WISH that my work is in the official repositories because it has all the rights. If I associate with the GNU license, I do not do any license infringement if that code uses objects that have no license GNU. If so I could not use them in GIMP and thousands of other programs, objects with different licenses.
Why my proposal of code is that it can be used on different repository objects (enabled CC licenses) through a simple addition to the XML code. My wish would be to do this only for certain types of objects in order to preserve the full GNU license for the part of NASAL code, XML ... Fgfs owes its superiority to other simulators just for the fact that the code associated to the individual aircraft is with the GNU (as it is for GIMP and other thousands of products compatible to the GNU license).
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Thorsten » Mon May 30, 2016 5:42 am

No problem, but one thing is Fgfs (container) and one thing is its content.


Well, thanks for making my work the container for your content. So if you do a 3d aircraft model this is content, if I figure out GLSL code to give you swarms of birds in the scene or a decent-looking afterburner flame this is container?

I might just disagree that there's such a clear distinction.

But as for non-GPL aircraft - keep them separate.

If you don't like a GPL plane, create one from scratch and release it under CC-whatever. Or commercially.

If you like a GPL plane, create one.

But to try to mix incompatible licenses file by file is no way forward for anything, it's just inviting trouble. If you want to be part of the FG project, do it GPL. If you want to retain full control over your work, don't do it GPL and don't use GPL. Both work in the FG economy.

You're asking to eat the lunch without paying for it - making full use of my work and all the goodies being part of a project has to offer, yet retaining full control of your (well not yours specifically) work.

Why would I want to support this?
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Thorsten » Mon May 30, 2016 7:14 am

Afterthought:

I guess this summarizes where we think differently:

FGFs can then play a winning game if, together with the great programmers working on various projects, it allows 3D modellers enthusiasts present their work, then following their rules, which are different from the rules of the programmers.


You argue we could get better 3d models by supporting the idea. I agree that this is likely true in the short term, but not a win in the long term.

The whole point of the GPL license is to make others publish GPL as well, to create a world in which there is lots of GPL licensed material available, rather than one in which every bit of useful content and software is controlled by someone. So in the short run FG might forgo a few 3d models where the modelers wish to retain control - but in the longer run, insisting in GPL with GPL will help to create a pool of free software licensed 3d models.

Since I happen to agree with that goal of GPL, I actually want to make it easy for you to publish your work under GPL as well, and I want that all GPL goodies are available for you (special rendering effects, canvas, ...) - whereas if you don't want to publish your work, I don't want to make this easy for you - I want you to realize that you have to do it all from scratch and that there is a benefit in using materials from others and sharing yours in return.

So I'll never agree to what you suggest for the simple reason that it goes against every reason why I choose a GPL license (even when some people try to make me re-think my decision over and over...). My goal is not to create the best aircraft for FG, my goal is to see these aircraft fully GPL licensed, and if that isn't done, then I prefer less stunning GPL work.

I don't think you'll ever convince the GPL enthusiasts that making it easy to opt out of the GPL requirement is a way forward.
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Re: G91-R: Combining incompatible licences in a single aircr

Postby abassign » Mon May 30, 2016 8:32 am

@Thorsen,

the GPL can not teach me anything, I use GPL software since 1999I use it exclusively both professional and private. I designed and produced only in SW area GPL, so I know very well what are its advantages, but I also know very well that is not a religion, GPL is an incredibly powerful tool for growth! But as Stallman has always affirmed, GPL is great for the software, but it is not just for content, there are other necessities them.

I'll give you another example:
Wikipedia has GPL only for its engine MediaWiki (GPL), while the contents are under Creative Commons "CC BY-SA 3.0" (Creative Commons Attribution ShareAlike 3.0)!

A plane flying into the FGFS consists of two parts, Code (XML, NASAL ... and I hope in the future Python, Ruby, Java ...) and images and 3D models. The first part can conveniently be licensed under the GPL, it is the greatest element that favors FGFS than other flight simulators.
The second part that contains images, sounds, 3D objects instead should have a CC license as they are content, as it does, for example, Wikipedia! There are various types of CC licenses, for example the GPL Foundation recommends the CC0 for documentation (http://www.gnu.org/licenses/license-rec ... tions.html). The same does not recommend the use of the GNU GPL for the contents as it is created to the code (container ...).

But your considerations highlight the fact that it is necessary for the FGFS existence, defending the possibility to change the code even airplanes and other found objects, not only, but it is also necessary to preserve them! Or prevent an author can claim the ability can take off, in his personal and exclusive discretion, an object from the repository!
Thus not even all the CC are fine! Such as a compatible CC license for objects in FGFS must ensure that such a license can not be changed later by the author! CC 3.0, and even more the 4.0 guarantee that fact to the legal level.

Commons license CC-BY-NC-ND 3.0 (or better, the Commons CC-BY-NC-ND 4.0) I find it appropriate to ensure that the graphical object (or audio ...) may not modify its license and in the same time that any company can take to use it commercially.
While the plane's code remains under the GPL, because GPL is the correct license (according to the same Stalliman that has always reiterated this point) for the code.

It would furthermore recommended that from now FGFS define, explicitly, a CC license for all graphic objects (Perhaps the "CC BY-SA 3.0" as Wikipedia ?) In order to start giving proper legal cover to the material that the volunteers fit inside. Suppose that tomorrow a certain Thorsen goes crazy and takes all the FGFS material and puts it on sale with a package, I really would be very unhappy about this! Unfortunately the graphic material has a license coverage they already have for it is not recognized the GPL (I do not know in your country, but in Italy it is!).

My proposal just serves to regulate such events, and to allow greater freedom of choice in accordance with the needs of each of us. GPL is a lighthouse of freedom, not a prison or worse a religion!
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Bomber » Mon May 30, 2016 8:36 am

If a programming language interpreter is released under the GPL, does that mean programs written to be interpreted by it must be under GPL-compatible licenses? (#IfInterpreterIsGPL)
When the interpreter just interprets a language, the answer is no. The interpreted program, to the interpreter, is just data; a free software license like the GPL, based on copyright law, cannot limit what data you use the interpreter on. You can run it on any data (interpreted program), any way you like, and there are no requirements about licensing that data to anyone.


GPL does make a distinction between code and data... Data that is being interpreted by a GPL program does not have to be GPL...

So tell me is the 3d file code or data..... does Flightgear interpret it and render it on the screen ?

If you accept it is data... does GPL allow data and code to be bundled..?
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Thorsten » Mon May 30, 2016 9:23 am

The second part that contains images, sounds, 3D objects instead should have a CC license as they are content, as it does, for example, Wikipedia!


You can in fact do this right now on the FGAddon repo if you pick a CC license which is GPL compatible. Some of them in fact are - others are not - as you point out, there's a zoo of CC licenses ranging from CC0 which is near-equal to public domain to very restrictive licenses which prevent commercial work and require to credit the original author.

The point is not the specific license, the point is that there needs to be a symmetry - if you get to modify and re-distribute my work, I should get to modify and re-distribute your work if you utilize mine.

GPL makes the specific bet that allowing commercial use is, on average, a good thing. There are both cases - cheap freeloaders like FlightProSim and genuine developments like Creare which gave us a very high quality skydiver FDM in return. So whatever CC license you pick, I suppose we're going to make the same bet with it.

So we always have the requirements:

* anyone adding to existing material or utilizing existing material must not close off whatever he adds to prevent further development
* material needs permission to be changed, modified, adapted and re-distributed to benefit other development in the project
* after the initial licensing, no further permission of the copyright holder should be necessary so that nobody can block development
* commercial use needs to be permitted to allow well-intended use cases which have benefited us much

You end up with GPL or something much like it. Whether it's actually GPL or not I don't care so much - feel free to license content CC-0 if you like for instance, it's quite welcome on FGAddon.

Just the idea of retaining control over your material doesn't fly.
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Re: G91-R: Combining incompatible licences in a single aircr

Postby bugman » Mon May 30, 2016 9:27 am

Hi abassign,

As I said before, if you create your own 3rd party hangar, as has been done in the FlightGear community consistently for the last 20 years, you are free to do as you wish.

That being said, you should carefully research open source licence compatibility. The reason being that you may loose legal control over one part of your aircraft due to licence clashes and ambiguity. Let me explain. First I'll break this up into different groups of people:

  • 3D content creator - this person can licence their content as they wish. They can distribute their content under their chosen licence. But if they distribute it with the rest of the aircraft, they then fall into the aircraft distributor category.
  • Aircraft distributor - this person is bound by the licences of all parts, and has fully legal responsibility for that copyrighted content.
  • End user - they have no legal responsibility and can enjoy the aircraft.
  • 3rd party - if someone forks the repository or creates a new repository and it is online, they become an aircraft distributor.
Here I am referring to the actions of the aircraft distributor, which can importantly cause the 3D content creator's models to fall under a different licence that they never intended. Firstly you need to understand the distinction between 'mere aggregation' and 'combining two modules into one program'. This is the language of the GPLv2. From the GPLv2 FAQ:

GNU GPLv2 FAQ wrote:What is the difference between "mere aggregation" and "combining two modules into one program"?
Mere aggregation of two programs means putting them side by side on the same CD-ROM or hard disk. We use this term in the case where they are separate programs, not parts of a single program. In this case, if one of the programs is covered by the GPL, it has no effect on the other program.

Combining two modules means connecting them together so that they form a single larger program. If either part is covered by the GPL, the whole combination must also be released under the GPL—if you can't, or won't, do that, you may not combine them.

What constitutes combining two parts into one program? This is a legal question, which ultimately judges will decide. We believe that a proper criterion depends both on the mechanism of communication (exec, pipes, rpc, function calls within a shared address space, etc.) and the semantics of the communication (what kinds of information are interchanged).

If the modules are included in the same executable file, they are definitely combined in one program. If modules are designed to run linked together in a shared address space, that almost surely means combining them into one program.

By contrast, pipes, sockets and command-line arguments are communication mechanisms normally used between two separate programs. So when they are used for communication, the modules normally are separate programs. But if the semantics of the communication are intimate enough, exchanging complex internal data structures, that too could be a basis to consider the two parts as combined into a larger program.

For aircraft in FlightGear, you have XML which glues everything together. You could leave it to a court to decide if this is aggregation or a whole, but because of this essential 'XML glue', they will very likely decide that this is a whole. The 'XML glue' is not a communication method. What does this mean? It means ambiguity with the licensing. A 3rd party could take the aircraft and decide that due to the licence clash of this "whole", that the GPLv2+ licence applies also to the 3D model. You would then have to sue this person to protect the rights of the 3D content creator, but because the court is likely to decide that this is a whole and not a mere aggregation, you probably won't be able to get the 3D model back. The only way would be if the 3D modeller has a court decision showing that you as a distributor were wrong to bundle the differently licensed content, and then the 3rd party also has no right to distribute the 3D model as GPL.

For a list of licences compatible with the GPL, see:

Note that you can use the GPLv3+ and CC-BY-SA-4.0, as these licences are deliberately compatible with each other. If you do not believe this assessment, please email <licensing att fsf.org> with the link to my post here. You will then receive a very definitive response!

Regards,
Edward
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Thorsten » Mon May 30, 2016 9:36 am

@Edward:

Here I am referring to the actions of the aircraft distributor, which can importantly cause the 3D content creator's models to fall under a different licence that they never intended.


For the record, after reading

http://www.gnu.org/licenses/gpl-faq.htm ... tarySystem

a few times, I think you have found the right way to put it. This explicitly says the difference is one of substance and form, so that resolves my point whether it makes a difference to offer an aircraft in one download link or in separate links.

I think you're fine by offering a differently licensed 3d model as a separate download for the user to install (aka 3d material intended for an aircraft can be considered bundled in principle), but that's not the same as packaging into one aircraft (aka, it makes a difference in what form you do this in practice).
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Bomber » Mon May 30, 2016 9:47 am

But a 3d model is simply not software....

And all that talks about is programs and executables.... not data.

And an xml file is a data file.... glue... that normally sticks 2 separate objects together doesn't it ?
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Thorsten » Mon May 30, 2016 9:49 am

Keep on reading Bomber - you're studying the right document - it's all explained in there :-)
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Bomber » Mon May 30, 2016 9:52 am

Bundling different programs is a no no if they are deemed a whole....

But it doesn't explicitly restrict programs and data with different licences being bundled..

We first need to understand is a 3d model file code or data ?
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Re: G91-R: Combining incompatible licences in a single aircr

Postby Thorsten » Mon May 30, 2016 9:56 am

We first need to understand is a 3d model file code or data ?


Hint: Not relevant here, because the rest of the aircraft doesn't render the model, FG does. But you're not bundling with of FG, you're bundling with the rest of the aircraft. So what matters is not the relation between the 3d model and FG but the relation between the rest of the aircraft and the 3d model.
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