Board index FlightGear Development Scenery

v0 landclasses

Questions and discussion about enhancing and populating the FlightGear world.

Re: v0 landclasses

Postby PINTO » Thu May 12, 2016 9:20 pm

Firstly,
wlbragg wrote in Thu May 12, 2016 9:06 pm:I'm not so sure FG has any obligation to provide raw v0 "data", it's not code.

It does not matter if it's code or data, as long as it's the source. To quote, The source code for a work means the preferred form of the work for making modifications to it. E.g. XML files can also be classified as data, yet they are still considered part of the source.

wlbragg wrote in Thu May 12, 2016 9:06 pm:Not a lawyer here but the "preferred form of the work" for all our scenery to me means v0 from the "original" source, NLCD from the "original" source.

Per sections 2 and 3, if the source is modified and then distributed, then the modified source must be made available. "Preferred form of work" doesn't mean preferred source of data, but preferred file structure for editing it.

wlbragg wrote in Thu May 12, 2016 9:06 pm:There is also the spirit of the GPL we're talking about here. I have no clue how one would interpret or argue that.

The GPL is a license/contract. The "spirit" that it has isn't too relevant, especially when we are talking about legalities.

@statto, see above.
Actively developing the MiG-21bis (github repo) (forum thread) (dev discord) (fg wiki)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 960
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

Re: v0 landclasses

Postby statto » Thu May 12, 2016 9:24 pm

PINTO wrote in Thu May 12, 2016 9:20 pm:@statto, see above.


I understand that, but the scenery data is different than the FlightGear source code, and thinking about it, while it's meant to be free, its license is ambiguous.
Custom Scenery available from http://www.stattosoftware.com/flightgear
statto
 
Posts: 2106
Joined: Fri Jan 25, 2008 9:57 pm

Re: v0 landclasses

Postby PINTO » Thu May 12, 2016 9:38 pm

Per http://wiki.flightgear.org/Howto:Make_an_airport#A_note_about_licenses and https://scenery.flightgear.org/LICENCE, the scenery is GPLv2, so the vmap0 data would still need be provided per GPLv2.

I couldn't find any other licensing sources (am at work), so feel free to correct me.
Actively developing the MiG-21bis (github repo) (forum thread) (dev discord) (fg wiki)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 960
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

Re: v0 landclasses

Postby bugman » Thu May 12, 2016 9:40 pm

statto wrote in Thu May 12, 2016 8:23 pm:My goal is to create data for release into the main FlightGear channels, ie TerraSync - however, I'm currently of the mindset that I don't want to release any beta versions under a non-restrictive copyright, so they don't end up in non-official channels.


For pre-releases, you are free to simply not license it (yet). For your work, you are the copyright owner, and you can choose to license it under the GNU GPL v2+ once you are happy with it. You can ask people to test the data, but they have no licence to redistribute. If you work with others, it would then be good to have a public agreement that the work will be GPLv2+ licensed for release (so that you don't have to get each individual person to make a public statement on release). Anyway, as Thorsten can attest to, this approach does not stop FGMEMBERS from taking and distributing the work. He used this exact approach for the Space Shuttle. The logic used is that it is originally GPLv2+ licensed, therefore they can apply the GPL licence to the work. As for different licences, FGMEMBERS takes all content from all sources irrespective of the licence (see FGMEMBERS-NONGPL/danube).

Regards,
Edward
bugman
Moderator
 
Posts: 1799
Joined: Thu Mar 19, 2015 9:01 am
Version: next

Re: v0 landclasses

Postby PINTO » Thu May 12, 2016 9:51 pm

To be upfront and clear, I am not an "FGMembers proponent".

bugman wrote in Thu May 12, 2016 9:40 pm:Anyway, as Thorsten can attest to, this approach does not stop FGMEMBERS from taking and distributing the work. He used this exact approach for the Space Shuttle.


You're right, I've opened this: https://github.com/FGMEMBERS/SpaceShuttle/issues/3

bugman wrote in Thu May 12, 2016 9:40 pm:As for different licences, FGMEMBERS takes all content from all sources irrespective of the licence (see FGMEMBERS-NONGPL/danube).


To be fair, they are not distributing the Danube in violation to the authors "license" - it does not restrict distribution in non-commercial environments. Also, most - if not all - other repos in the NON-GPL org are some variant of the Creative Commons license (I did not audit all aircraft in there).
Actively developing the MiG-21bis (github repo) (forum thread) (dev discord) (fg wiki)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 960
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

Re: v0 landclasses

Postby bugman » Thu May 12, 2016 9:54 pm

True, my statement was too broad. They take all reditributable content from all sources.

Cheers,
Edward
bugman
Moderator
 
Posts: 1799
Joined: Thu Mar 19, 2015 9:01 am
Version: next

Re: v0 landclasses

Postby statto » Thu May 12, 2016 11:03 pm

PINTO wrote in Thu May 12, 2016 9:38 pm:Per http://wiki.flightgear.org/Howto:Make_an_airport#A_note_about_licenses and https://scenery.flightgear.org/LICENCE, the scenery is GPLv2, so the vmap0 data would still need be provided per GPLv2.

I couldn't find any other licensing sources (am at work), so feel free to correct me.


Thanks for the link, that's what I was looking for and could not find.

The source code for a work means the preferred form of the work for
making modifications to it.

If distribution of executable or object code is made by offering
access to copy from a designated place, then offering equivalent
access to copy the source code from the same place counts as
distribution of the source code, even though third parties are not
compelled to copy the source along with the object code.


Here's what I think:
1) From a licensing perspective, FlightGear scenery is different from the base FlightGear executable
2) Nevertheless, FlightGear scenery is still distributed based on the GPLv2
3) FlightGear scenery is broken up into three components
a) For objects data, the scenemodels repository takes care of all and any source code requirements, as the .ac files and image files distributed with every model are the preferred form of the work for modifications
b) For terrain data, taking the mapserver offline removed an offering from a designated place, however, the files used to generate the scenery are publicly available on other websites, though I would recommend we put the data up on a FlightGear server somewhere just to be on the safe side until we get the new mapserver up and running. This assumes the raw files are not the preferred form of the work for modifications, though you can still modify them if you know what you're doing.
c) For airport data, apt.dat is included and necessary to run FlightGear

Does this seem right?
Custom Scenery available from http://www.stattosoftware.com/flightgear
statto
 
Posts: 2106
Joined: Fri Jan 25, 2008 9:57 pm

Re: v0 landclasses

Postby PINTO » Thu May 12, 2016 11:25 pm

Yeah, that looks good to me, other than:

statto wrote in Thu May 12, 2016 11:03 pm: b) For terrain data, taking the mapserver offline removed an offering from a designated place, however, the files used to generate the scenery are publicly available on other websites, though I would recommend we put the data up on a FlightGear server somewhere just to be on the safe side until we get the new mapserver up and running. This assumes the raw files are not the preferred form of the work for modifications, though you can still modify them if you know what you're doing.


FlightGear terrasync terrain data uses modified data in some places,( such as the recently upgraded islands that were put in, the Azores, see here and here) - therefore, terrain source data has been modified, and that modified source would need to be made available through official channels.

If I'm wrong on the modified scenery, let me know - I only have a moderately basic understanding of the scenery, having never built any myself. I have added buildings but thats about the extent of my involvement there. And I haven't looked at all modifications done to WS2.0, so there may be more instances of this.

Also, if the majority of the scenery developers are actively using the raw files for making scenery, then that could be argued that it is "preferred". As it stands, however, I don't think any of our scenery devs are doing this, are they not?
Actively developing the MiG-21bis (github repo) (forum thread) (dev discord) (fg wiki)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 960
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

Re: v0 landclasses

Postby statto » Thu May 12, 2016 11:31 pm

I made the assumption on the last part for that very reason mentioned.

Also, the Azores scenery was created using a variety of freely available sources, including OpenStreetMap data - I could recreate the scenery if I wanted to using the available channels mentioned in that mailing list. I'm not sure if that makes a difference in terms of how the data is distributed under the GPL - the GPL allows you to distribute any way you want as long as getting the source code isn't harder than getting the executable (in this instance, the compiled scenery would be the "executable")
Last edited by bugman on Fri May 13, 2016 6:41 am, edited 1 time in total.
Reason: No need to quote the entire previous post.
Custom Scenery available from http://www.stattosoftware.com/flightgear
statto
 
Posts: 2106
Joined: Fri Jan 25, 2008 9:57 pm

Re: v0 landclasses

Postby PINTO » Thu May 12, 2016 11:53 pm

(On mobile, short reply sorry)

Yeah but the distributor (in this case, Flightgear), needs to be able to provide the modified source. As long as they can, they're fine. I'm not sure how applicable a patchwork of download links as compared to the source data to build it directly would be.

Distribution methods are spelled out pretty plainly in sections 3.a, 3.b, and 3.c of the GPL.

EDIT: if I were going with a plain reading of the GPL, I'd say FG is responsible for distributing the source, not 3rd parties.

Also, relying on 3rd parties is probably a bad practice in case they take their data down, or otherwise make it unavailable.
Actively developing the MiG-21bis (github repo) (forum thread) (dev discord) (fg wiki)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 960
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

Re: v0 landclasses

Postby PINTO » Fri May 13, 2016 3:07 am

bugman wrote in Thu May 12, 2016 9:40 pm:He used this exact approach for the Space Shuttle. The logic used is that it is originally GPLv2+ licensed, therefore they can apply the GPL licence to the work.


I just spent 30 minutes of my life researching this, and the Thorsten's space shuttle is GPL (as found in FGAddon). It doesn't have any GPL notices, however.
Actively developing the MiG-21bis (github repo) (forum thread) (dev discord) (fg wiki)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 960
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

Re: v0 landclasses

Postby Thorsten » Fri May 13, 2016 4:56 am

I just spent 30 minutes of my life researching this, and the Thorsten's space shuttle is GPL (as found in FGAddon).


Yes, the idea is that placing it on FGAddon constitutes the release under GPL of that particular version. Doesn't mean you are free to take any other non-released development code though. Specifically if I say I don't want to release a version yet.

Landclass data: My understanding is that giving a link to the v0 server to any interested party on request fulfills the GPL requirements. As for the custom addition (Azores) - Torsten specifically asked the author to provide such a link on e.g. the wiki and to upload the landclass files for that purpose.

The GPL is intended to make sure the sources can not be hidden, but doesn't contain a requirement to spoon-feed it to users.

https://www.gnu.org/licenses/old-licens ... OfferValid

If you choose to provide source through a written offer, then anybody who requests the source from you is entitled to receive it.

If you commercially distribute binaries not accompanied with source code, the GPL says you must provide a written offer to distribute the source code later. When users non-commercially redistribute the binaries they received from you, they must pass along a copy of this written offer. This means that people who did not get the binaries directly from you can still receive copies of the source code, along with the written offer.


That's V2 - the FG license by the way, supposedly that part is different in V3.

(And yes, I feel safe to rely on the NASA document server to stay online for a while...)

Come to think of it, I'm not completely sure what scenery mesh is. It's source is facts (not copyrightable as such), obtained from a public domain collection (not copyrightable as such) processed in a deterministic way by a tool (terragear) - two people processing the same input data collection will get the same output. Does this even fall under copyright then?
Thorsten
 
Posts: 11765
Joined: Mon Nov 02, 2009 8:33 am

Re: v0 landclasses

Postby wlbragg » Fri May 13, 2016 5:10 am

The "official" FG aircraft repository has some 300+ GPL aircraft in it. Of those aircraft, how many of them have every piece of derived artwork leading up to the creation of the final texture/s that was supplied with the aircraft? Which step of those "derived pieces of texture/artwork" is the "preferred" source?

If I use v0 from site (a) to make my scenery and and site (a) is a mirror or a reproduction of site (b), which is the preferred source?

If 10 lines of code in aircraft (a)'s 100 lines of set.xml in FG's "official" repo originated from site (b)'s set.xml (which was the total 10 lines only) who used those same 10 lines of code out of a 20 line set.xml from site (c)'s and all three 10 lines of code are identical, does site (a) have to provide a separate site (b) copy of the 10 lines of xml? Or is the final 100 lines that contain the 10 lines sufficient.

And what does the GPL legal document say happens when the the only known source of original code or data that a derived work is created from is destroyed by accident or act of God?

It all starts to get a bit fuzzy if you ask me.

The "spirit" that it has isn't too relevant, especially when we are talking about legalities.

I disagree, I think "spirit of the law" is very relevant and probably the final deciding factor in many legal decisions.

But I conceded, this is all just my opinion which may be based on very flawed reasoning.
Kansas(2-27-15)/Ohio/Midwest scenery development.
KEQA (2-27-15), 3AU, KRCP Airport Layout
Intel i5 3570K AMDRX480
User avatar
wlbragg
 
Posts: 5874
Joined: Sat Aug 25, 2012 11:31 pm
Location: Kansas (Tornado Alley), USA
Callsign: WC2020
Version: next
OS: Win10/Linux/AMDRX480

Re: v0 landclasses

Postby Thorsten » Fri May 13, 2016 5:21 am

If 10 lines of code in aircraft (a)'s 100 lines of set.xml in FG's "official" repo originated from site (b)'s set.xml (which was the total 10 lines only) who used those same 10 lines of code out of a 20 line set.xml from site (c)'s and all three 10 lines of code are identical, does site (a) have to provide a separate site (b) copy of the 10 lines of xml? Or is the final 100 lines that contain the 10 lines sufficient.


Bad example, because xml or Nasal code are their own source code, so you can distribute them 'as is' without any particular additional obligation.

If I use v0 from site (a) to make my scenery and and site (a) is a mirror or a reproduction of site (b), which is the preferred source?


The thing I'm wondering is in what sense geodata would be source code. For aircraft, the equivalent would be performance data ( facts) - which you distribute embedded in generic structures. However, we do usually not include all the original documents with the aircraft (they might in fact be copyrighted! - just the facts they contain may be free), we rather link them.
Thorsten
 
Posts: 11765
Joined: Mon Nov 02, 2009 8:33 am

Re: v0 landclasses

Postby PINTO » Fri May 13, 2016 5:56 am

I can see my opinion isn't very popular, so whatevs. I'm not interested in arguing or getting people upset. Interpret it how you will, I've said what I think.

pinto, out!
Actively developing the MiG-21bis (github repo) (forum thread) (dev discord) (fg wiki)

http://opredflag.com is an active flightgear dogfighting community (using a system that isn’t bombable)
User avatar
PINTO
 
Posts: 960
Joined: Wed Oct 21, 2015 6:28 pm
Callsign: pinto
Version: 2016.3.0
OS: Win10

PreviousNext

Return to Scenery

Who is online

Users browsing this forum: Google [Bot] and 1 guest