Board index FlightGear Development Aircraft Flight dynamics model

License Question :?

Good sims require good FDMs (the "thing" that makes an aircraft behave like an aircraft).

License Question :?

Postby 439Tiger » Thu Mar 01, 2012 6:04 pm

I did not want to clutter the F/A-XX thread so I'm starting a new one here.

sgofferj wrote in Thu Mar 01, 2012 4:51 pm:
GPLv2 wrote:2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions:

a) You must cause the modified files to carry prominent notices stating that you changed the files and the date of any change.
b) You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License.
c) If the modified program normally reads commands interactively when run, you must cause it, when started running for such interactive use in the most ordinary way, to print or display an announcement including an appropriate copyright notice and a notice that there is no warranty (or else, saying that you provide a warranty) and that users may redistribute the program under these conditions, and telling the user how to view a copy of this License. (Exception: if the Program itself is interactive but does not normally print such an announcement, your work based on the Program is not required to print an announcement.)



Ok I think I understand. But what I'm not sure about is how come it does not seem to be reciprocal? I'm playing devil's advocate here :twisted:

We're saying that we cannot accept CC licensed aircraft into the main distribution, so therefore everything has to be GPL, then how is it that we have the Citation X, the B1900D and the Twin Otter? Syd's aircraft are CC share alike but we still include them? :?

Again, I'm just playing devil's advocate, wouldn't it be better for FlightGear to be CC BY-NC-SA 3.0 which does not restrict modifications but would protect us from scammers?

But then again, I might be missing something. 8)
Specializing in Canadian built aircraft and aircraft flown by the RCAF

http://www.flightgearcanada.ca/ or: https://sites.google.com/site/flightgearcanada/
User avatar
439Tiger
 
Posts: 1164
Joined: Sat Jan 01, 2011 2:39 am
Location: St-Georges-de-Beauce, Québec, Canada (CYSG)
Callsign: C-CYSG
Version: 2.10.03
OS: Windoze 7

Re: License Question :?

Postby sgofferj » Thu Mar 01, 2012 6:42 pm

In fact, I have been wondering a bit about the license issues myself. To my understanding, the GPL is for software programs. I wonder how much it actually can be applied to artwork as strictly spoken, artwork doesn't have a "source code". Opposed to that, the CC licenses are mainly for artwork and might not be suitable for software programs.

The problem with NC variants of the CC license is that it - to my understanding - not only prohibit commercial redistribution but also commercial use, which means, no pilot's school could legally use Flightgear any more without it being dual licensed.

However, I'm not a lawyer and copyright law also differs from country to country, so the best I can do is speculate, which I don't like to do on matters of importance.

About the scammers, there might be a possibility to get them held responsible, depending on how careful they were. First of all, they must provide a copy of the source code. If they don't, there is the first possibility to sue them. Second, strictly spoken, they cannot sell Flightgear itself (i.e. the software or a license to use the software). Section 2b of the GPLv2 clearly excludes this possibility.

Section 1 of the GPLv2 also says they can only charge a reasonable fee for their work, i.e. compiling, creating the DVDs, etc.

GPLv2 wrote:1. You may copy and distribute verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the Program a copy of this License along with the Program.

You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee.


So if those scammers even remotely create the impression to the customer of selling the software (i.e. a license to use), that should be another possibility to sue them.

The Free Software Foundation - among other things - does help dealing with exactly those kind of issues and has supported Open Source projects in prosecuting infringements before.
Given the audacity of these scammers, I personally would have pursued this matter already but that is solely the decision of the core project maintainers.
FG 3.1 GIT / Opensuse 12.3 / Phenom II X4 / GForce GTX560
Stefan's little Flightgear corner | The Finnish Weather Center | Wolves in Finland

Working on: EFTP
COM: IAX2:home.gofferje.net/stefan (MO-FR 0700-2000 UTC, SA+SU 0900-2000 UTC)
sgofferj
 
Posts: 789
Joined: Mon Dec 05, 2011 4:13 pm
Location: EFTP
Callsign: OH-SW
Version: 3.1 GIT
OS: Opensuse

Re: License Question :?

Postby stuart » Thu Mar 01, 2012 10:35 pm

Hi Guys,

As the author of the work, Syd is entitled to license his aircraft under multiple licenses, so he may license them in his own hangar under CC share-alike, but under the FG hangar as GPL. He obviously needs to be careful if other people contribute to his aircraft.

CC BY-NC-SA would restrict usage commercially, and is less "free" than GPL. For many core developers (myself included) that would not be acceptable, as it would significantly reduce the freedom of the project. Aside from that, it is practically impossible to change the license, as we would need to track down everyone who has ever contributed to FG and get their permission to change the license.

Finally, regarding the Pro Flight Sim distributors etc. I would refer you to the mailing list where this has been discussed in detail, and the statement on the FG website (http://www.flightgear.org/flightprosim.html), which was agreed by the core development team after a long and careful discussion. AFAICT, Pro Flight Sim etc. are not in breaking the GPL.

-Stuart
G-MWLX
User avatar
stuart
Moderator
 
Posts: 1591
Joined: Wed Nov 29, 2006 9:56 am
Location: Edinburgh
Callsign: G-MWLX

Re: License Question :?

Postby sgofferj » Fri Mar 02, 2012 2:36 am

Yes, I have read the statement and a bit of the discussion. As written, I'm not a lawyer and I haven't had a closer look at the PFS people. However, I have been following a couple of GPL violation cases in the past with interest and I think, there might be the 2 mentioned options to pursue the matter, but this has to be determined by very close and detailed examination of PFS and the distribution method.
But - again as written - that is not within my scope of decisions and the decision already has been made, so...
FG 3.1 GIT / Opensuse 12.3 / Phenom II X4 / GForce GTX560
Stefan's little Flightgear corner | The Finnish Weather Center | Wolves in Finland

Working on: EFTP
COM: IAX2:home.gofferje.net/stefan (MO-FR 0700-2000 UTC, SA+SU 0900-2000 UTC)
sgofferj
 
Posts: 789
Joined: Mon Dec 05, 2011 4:13 pm
Location: EFTP
Callsign: OH-SW
Version: 3.1 GIT
OS: Opensuse

Re: License Question :?

Postby El Flauta » Fri Mar 02, 2012 4:54 am

To go to cruelly kill this ProSim's scammer, is allowed by GPL? :)
Vive FlightGear! Have you a Ñ on your keyboard? Spain-LatinAmerica FlightGear community!
--
PZL M18B Dromader
CASA C-101 Aviojet
Cessna 337G Skymaster
User avatar
El Flauta
 
Posts: 426
Joined: Fri Mar 14, 2008 12:09 am
Location: SCVM, Chile
Callsign: CC-FLT
Version: 3
OS: Windows 7 SP1

Re: License Question :?

Postby 439Tiger » Fri Mar 02, 2012 1:15 pm

Do you mean this literally or figuratively??? :mrgreen: :twisted:
Specializing in Canadian built aircraft and aircraft flown by the RCAF

http://www.flightgearcanada.ca/ or: https://sites.google.com/site/flightgearcanada/
User avatar
439Tiger
 
Posts: 1164
Joined: Sat Jan 01, 2011 2:39 am
Location: St-Georges-de-Beauce, Québec, Canada (CYSG)
Callsign: C-CYSG
Version: 2.10.03
OS: Windoze 7

Re: License Question :?

Postby sgofferj » Fri Mar 02, 2012 1:47 pm

Well, the GPL does not prohibit either. However, I'm not quite sure but there might be other regulations which would be violated by the mentioned actions ^^.
FG 3.1 GIT / Opensuse 12.3 / Phenom II X4 / GForce GTX560
Stefan's little Flightgear corner | The Finnish Weather Center | Wolves in Finland

Working on: EFTP
COM: IAX2:home.gofferje.net/stefan (MO-FR 0700-2000 UTC, SA+SU 0900-2000 UTC)
sgofferj
 
Posts: 789
Joined: Mon Dec 05, 2011 4:13 pm
Location: EFTP
Callsign: OH-SW
Version: 3.1 GIT
OS: Opensuse

Re: License Question :?

Postby Hooray » Fri Mar 02, 2012 1:57 pm

It is still astounding how many people have a wrong understanding of the GPL and its legal implications, you don't need to be a lawyer to understand and interpret it properly, it's more liked boolean logic once you read it phrase by phrase... ;-)

If you want to deal with those FPS scammers, you really only need to send the official FG statement to where the money is, i.e. the affiliate networks (i.e. ClickBank.com and CommissionJunction.com) and payment gateways (PayPal) they're using and let them know that this is a scam, a rip off that's been causing lots of irritation and confusion among FlightGear users.

It might help to forward some official statements mentioning this scam.

They won't help you to avoid legal trouble, but rather to avoid dubious users who tend to cause a fair share of work, too.
Please don't send support requests by PM, instead post your questions on the forum so that all users can contribute and benefit
Thanks & all the best,
Hooray
Help write next month's newsletter !
pui2canvas | MapStructure | Canvas Development | Programming resources
Hooray
 
Posts: 12288
Joined: Tue Mar 25, 2008 8:40 am

Re: License Question :?

Postby 439Tiger » Fri Mar 02, 2012 2:21 pm

sgofferj wrote in Fri Mar 02, 2012 1:47 pm:Well, the GPL does not prohibit either. However, I'm not quite sure but there might be other regulations which would be violated by the mentioned actions ^^.


:lol:
Specializing in Canadian built aircraft and aircraft flown by the RCAF

http://www.flightgearcanada.ca/ or: https://sites.google.com/site/flightgearcanada/
User avatar
439Tiger
 
Posts: 1164
Joined: Sat Jan 01, 2011 2:39 am
Location: St-Georges-de-Beauce, Québec, Canada (CYSG)
Callsign: C-CYSG
Version: 2.10.03
OS: Windoze 7

Re: License Question :?

Postby Groucho » Fri Mar 02, 2012 3:08 pm

Hooray wrote in Fri Mar 02, 2012 1:57 pm:If you want to deal with those FPS scammers, you really only need to send the official FG statement to where the money is, i.e. the affiliate networks (i.e. ClickBank.com and CommissionJunction.com) and payment gateways (PayPal) they're using and let them know that this is a scam, a rip off that's been causing lots of irritation and confusion among FlightGear users.

It might help to forward some official statements mentioning this scam.

They won't help you to avoid legal trouble, but rather to avoid dubious users who tend to cause a fair share of work, too.


I have pointed out the following some while ago:
If you have clear evidence that FPS is violating the GPL then you will have to show it, otherwise you are not legally allowed to spread this allegation. They in fact could sue everybody doing this with a good chance for success. Actually I have not seen anyone being able to come up with this evidence as far as code and software is concerned. FPS has obviously learned from the past and fixed a few legal issues which could have made them prone to legal attacks.
False advertising is a totally different topic which has nothing to do with GPL violations. If it is about screen shots and movies this is an issue of copyrights in general.
_____________________________________
Callsign: D-HARP
Flight locations: TNCM, TKPK, EDNY, LOWI
Aircrafts
Helis: EC130, Bo105, UH-1, R22
Twins/Jets: Aerostar, CRJ-200
User avatar
Groucho
 
Posts: 1212
Joined: Sun Jun 17, 2007 10:28 am
Location: Airborne Lake Constance/Germany
Callsign: D-HARP
Version: GIT
OS: Kubuntu

Re: License Question :?

Postby HHS » Fri Mar 02, 2012 4:36 pm

Groucho wrote in Fri Mar 02, 2012 3:08 pm:I have pointed out the following some while ago:
If you have clear evidence that FPS is violating the GPL then you will have to show it, otherwise you are not legally allowed to spread this allegation. They in fact could sue everybody doing this with a good chance for success. Actually I have not seen anyone being able to come up with this evidence as far as code and software is concerned....


On our homepage, and a lot of reviews about 2.6 is the correct statement about our problem with FPS et al. No need to worry about.

And there was another point some while ago:
1.)They have to provide the source- do they? And if they do- are they usuable?
I once found the location of the source on their homepage- but the package I got was corrupted....And I was not the only one.
Is this correct and compatible with GNU GPL? I doubt it....

At least we are not the only one- Blender has the same problem: http://www.blender.org/blenderorg/blend ... g-blender/
Up, up and away
User avatar
HHS
 
Posts: 3623
Joined: Thu Jul 19, 2007 8:09 am
Version: GIT

Re: License Question :?

Postby Hooray » Fri Mar 02, 2012 6:49 pm

@Groucho: I didn't say anything about them violating the GPL at all, instead I referred to them being a scam, and ripping off people, on the basis of misinforming people.

That alone, is often enough to alert people (and companies) to stop doing business with such folks, because they tend to cause a fair amount of work, too.

Regarding the GPL, there are many false assumptions being made here, and I am not going to comment on them publicly, because that would only strengthen the FPS guys.

Let me just say that I do perfectly understand the implications of the GPL, and that I was also once involved in customizing open source software where one of the primary requirements was that NO modified code whatsoever would be shared with other parties.
This is a scenario that is definitely possible, and also legal. There are lawyers making TONS of money by finding such loop holes.

Really, you cannot deal with such scams on the legal basis of the GPL, it would be VERY easy to comply 100% with all the licensing requirements of the GPL, while still running such scams and ripoffs and making thousands of dollars each week, if not even each day!

These websites can be created automatically using scripts (most of them are customized WordPress installs), they are uploaded to bulk-registered domains, using link-building services and SEO services.

It is far too easy to make LOTS of cash like this. Just check out any "blackhat" forum, and you may actually meet some of the people behind such scams.

To deal with such problems, you need to be open about the whole thing - you need to find other parties involved (such as Mozilla, Blender and other projects) and form an association to inform people.

That will give your voice a certain weight and momentum, so that you can actually start writing to companies like clickbank/CJ (affiliate networks) or PayPal/MoneyBookers to have them support us.

Reporting the websites involved as scams (i.e. using google) would also be helpful:
https://www.google.com/webmasters/tools ... l=en&pli=1
Please don't send support requests by PM, instead post your questions on the forum so that all users can contribute and benefit
Thanks & all the best,
Hooray
Help write next month's newsletter !
pui2canvas | MapStructure | Canvas Development | Programming resources
Hooray
 
Posts: 12288
Joined: Tue Mar 25, 2008 8:40 am

Re: License Question :?

Postby Bomber » Fri Mar 02, 2012 8:31 pm

Your (FG's) problem is a lack of imagination in dealing with this issue.

Take the gloves off and program your way out of the problem.. I can assure you T4T wont suffer from it.

Simon.
"If anyone ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me - it's all balls" - R J Mitchel
Bomber
 
Posts: 1933
Joined: Fri Dec 14, 2007 7:06 pm
OS: Windows XP and 10

Re: License Question :?

Postby Hooray » Fri Mar 02, 2012 9:07 pm

Bomber wrote in Fri Mar 02, 2012 8:31 pm:Your (FG's) problem is a lack of imagination in dealing with this issue.

no, it certainly isn't - it's (again) your lack of doing a mailing list search prior to posting here, which lead you to false conclusions.

Bomber wrote in Fri Mar 02, 2012 8:31 pm:Take the gloves off and program your way out of the problem..

In fact, this has been attempted before - and it caused quite some irritation among fellow contributors, it only takes a quick mailing list search to see how many flamewars were caused by such "creative programming". FlightGear is open source, and GPL, for a reason.

For example, I am referring here to hard coded routines coded directly into the C++ source code that were meant to obfuscate certain code and that were implemented by long-term FlightGear core developers who are intimately familiar with the FlightGear code bases.

I can assure you T4T wont suffer from it.

Okay, that's a bold statement, especially coming from someone who -quite obviously- isn't familiar with the FlightGear code base, certainly not when compared to long term core developers who already tried to "program their way out of the problem" previously.

On the other hand, it doesn't really surprise me particularly, because if I remember correctly, it was the T4T project which suggested implementing DRM measures and DRM-aware plugins to "protect" FlightGear artwork, right?

As long as your code is GPL, and thus open source, it isn't really complicated to deal with hard-coded measurements.
Admittedly, you might not face the same problems, but that will most likely come down to a lack of momentum initially - once your project gains momentum (if it does), there are going to be copycats - including people trying to resell your work by simply rebranding it.

If you want to prevent this legally, you simply cannot base your fork on GPL'ed code, which expressibly provides the legal framework for people to branch, fork, rebrand and sell your works.

The implications of "creative programming" techniques to make such things harder were critically discussed on the FG developers mailing list, including some pretty harsh words - even though the people involved in this, have been a part of the project for over a decade.

Look, there are people around here who have probably spent more time working with kernel debuggers and assembly code than they'd care to care admit. So the knowledge to make things harder is definitely there, but obfuscating open source code and actively working towards preventing reverse engineering is simply a nogo.

Really, there is nothing wrong about people making money off open source software - in fact, it's great. Especially, if that means that core developers get to make a living working on it. This is a common theme in some projects, like gcc or firefox for example.

Likewise, there's is NOTHING WHATSOEVER wrong about people (or project's like yours) branching or even forking an OSS project (in fact, it's encouraged!), and if they manage to make money doing so, even better!

The only real problem here is, people reselling a rebranded and outdated version of FlightGear without adding any visible additional value to it, be it in the form of documentation, programs/tools or services (support), building their entire business model on spreading misinformation and doing huge SEO-campaigns to reach tens ouf thousands of ill-informed people with their affiliate "product", mispresenting FlightGear as something which it simply isn't.

Just imagine for a second that you had to work around dozens of hard-coded routines to start forking FlightGear for your T4T project, quite probably implemented by more experienced C++ developers than your own, and people much more familiar with SG/OSG and FG internals than your own coders. You would have to spend considerable resources on doing stupid reverse engineering. That's not what OSS is all about.

Finally, I keep being amazed by some of your bold statements, and at least to me, it's seems to be getting increasingly obvious why you are having such a hard time attracting more help and support: your politics (and priorities!) simply do not align very well with the rest of the FG development apparently.

Anyway, good luck.
Please don't send support requests by PM, instead post your questions on the forum so that all users can contribute and benefit
Thanks & all the best,
Hooray
Help write next month's newsletter !
pui2canvas | MapStructure | Canvas Development | Programming resources
Hooray
 
Posts: 12288
Joined: Tue Mar 25, 2008 8:40 am

Re: License Question :?

Postby Bomber » Fri Mar 02, 2012 9:56 pm

There's definately something wrong with someone making money from someone elses hard work.
"If anyone ever tells you anything about an aeroplane which is so bloody complicated you can't understand it, take it from me - it's all balls" - R J Mitchel
Bomber
 
Posts: 1933
Joined: Fri Dec 14, 2007 7:06 pm
OS: Windows XP and 10

Next

Return to Flight dynamics model

Who is online

Users browsing this forum: No registered users and 2 guests