Hello
I'm developing a game and its almost done and i would like to sell it. I was just wounding how can I tell if the library's I'm using are for commercial project use or not ? Also in the future how can i tell if a certain library or code is for commercial projects or not ?
Also there are a lot of license out there why?

can I use those library/API for commercial projects?

1-libjpeg
2-libpng
3-SFML
4-OpenAL
5-OpenGL

thank you for your help.

Hello
I'm developing a game and its almost done and i would like to sell it. I was just wounding how can I tell if the library's I'm using are for commercial project use or not ? Also in the future how can i tell if a certain library or code is for commercial projects or not ?
Also there are a lot of license out there why?

can I use those library/API for commercial projects?

1-libjpeg
2-libpng
3-SFML
4-OpenAL
5-OpenGL

thank you for your help.

read the licenses:

libjpg

LEGAL ISSUES ============ In plain English: 1. We don't promise that this software works. (But if you find any bugs, please let us know!) 2. You can use this software for whatever you want. You don't have to pay us. 3. You may not pretend that you wrote this software. If you use it in a program, you must acknowledge somewhere in your documentation that you've used the IJG code.
[/quote]

libpng:
http://libpng.org/pu...png-LICENSE.txt (If you redistribute the sourcecode there are some things to keep in mind)

SFML:
http://www.sfml-dev.org/license.php (Basically the same as for libpng)

OpenAL:
Depends on version, prior to 1.1 it is LGPL (Which you can use for commercial works as long as the end user is able to replace or modify the OpenAL library (This means you can't use it on some locked down platforms)), after 1.1 it is a proprietary license which is shown when you run the installer.
OpenGL:
Depends on implementation, in most cases you will not distribute the implementation so it is irrelevant.

Hello
I'm developing a game and its almost done and i would like to sell it. I was just wounding how can I tell if the library's I'm using are for commercial project use or not ? Also in the future how can i tell if a certain library or code is for commercial projects or not ?
Also there are a lot of license out there why?

can I use those library/API for commercial projects?

1-libjpeg
2-libpng
3-SFML
4-OpenAL
5-OpenGL

thank you for your help.

Each library should contain some kind of license, often displayed when installing the lib. Atleast it should be contained somewhere in the lib-package you have downloaded/installed/unzipped or on the website.

By the way, more dangerous are some licenses like GPL or LGPL, which are seen as viral licenses and can hurt your purpose, so read these licenses really carefully !

When you want to sell your project, you need some kind of EULA. Instead of writing your own EULA you should create one in coporation with a laywer. He should take a look at all the licenses you incoparated into your software.

SFML:
http://www.sfml-dev.org/license.php (Basically the same as for libpng)

This license regards only the SFML code, doesn't it ? Doesn't SFML use several external libs with their own licenses ?

[quote name='SimonForsman' timestamp='1322659088' post='4889048']
SFML:
http://www.sfml-dev.org/license.php (Basically the same as for libpng)

This license regards only the SFML code, doesn't it ? Doesn't SFML use several external libs with their own licenses ?
[/quote]

True:

• GLEW is under the BSD license, the SGI license or the GLX license
• OpenAL-Soft is under the LGPL license
• libsndfile is under the LGPL license
• stb_vorbis is public domain
• libjpeg is public domain
• libpng is under the zlib/png license
• zlib is under the zlib/png license
• SOIL is public domain
• freetype is under the FreeType license or the GPL license[/quote]
  
  I don't know how SFML works as i've never used it but it shouldn't be difficult to strip out any external libraries with an unsuitable license.
  (The big potential problems are OpenAL-Soft and libsndfile if you are targeting for example iOS)

ok isn't just easier to just use SFML (1 library) with OpenGL to load Images, Audio etc.. instead of using 10 library's?

another thing SFML say
"SFML is completely free for any use, commercial or not, open-source or not. That is, you can use SFML API in your project without any restriction."
so that means i can use SFML and when i want to sell my game just make a readme.txt and say in it that i used SFML in my project.

also one more thing, will there be a performance difference between one software that uses 10 library's and another software that uses only 1 library ?

ok isn't just easier to just use SFML (1 library) with OpenGL to load Images, Audio etc.. instead of using 10 library's?

another thing SFML say
"SFML is completely free for any use, commercial or not, open-source or not. That is, you can use SFML API in your project without any restriction."
so that means i can use SFML and when i want to sell my game just make a readme.txt and say in it that i used SFML in my project.

also one more thing, will there be a performance difference between one software that uses 10 library's and another software that uses only 1 library ?

As far as I understand, the problem with SFML is, that it is partly a wrapper. SFML (optionally) uses for example OpenAL-soft implementation to enable sound support. So, the SFML wrapper code is free, but the used OpenAL-soft lib can only be used under the LGPL license (normally a 'wrapper' license can't overwrite the license of used libs).

That is, you can use SFML with its very liberate license, but it could happen, that you can't use all features of it, when you want to avoid certain sub licenses like the LGPL (i.e. sound will not work on all devices etc.)

I, for one, keep away from LGPL/GPL licenses after talking to my lawyer (the viral nature of these licenses could be difficult). An other issue is, that most licenses are written under US law, when your are living in an other country (i.e. EU) , these licenses could have an other interpretation. This (and other issues..) was the reason I got rid off SDL and OpenAL and reimplemented it using standard Win-APIs, sometimes you incoparate a lib but only use a very small portion of it ...

But this is only my personal reaction to LGPL licenses. The best advice I could give sofar is, check what library you really need and finally talk to a lawyer.

[quote name='FantasyVI' timestamp='1322661343' post='4889059']
ok isn't just easier to just use SFML (1 library) with OpenGL to load Images, Audio etc.. instead of using 10 library's?

another thing SFML say
"SFML is completely free for any use, commercial or not, open-source or not. That is, you can use SFML API in your project without any restriction."
so that means i can use SFML and when i want to sell my game just make a readme.txt and say in it that i used SFML in my project.

also one more thing, will there be a performance difference between one software that uses 10 library's and another software that uses only 1 library ?

As far as I understand, the problem with SFML is, that it is partly a wrapper. SFML (optionally) uses for example OpenAL-soft implementation to enable sound support. So, the SFML wrapper code is free, but the used OpenAL-soft lib can only be used under the LGPL license (normally a 'wrapper' license can't overwrite the license of used libs).

That is, you can use SFML with its very liberate license, but it could happen, that you can't use all features of it, when you want to avoid certain sub licenses like the LGPL (i.e. sound will not work on all devices etc.)

I, for one, keep away from LGPL/GPL licenses after talking to my lawyer (the viral nature of these licenses could be difficult). An other issue is, that most licenses are written under US law, when your are living in an other country (i.e. EU) , these licenses could have an other interpretation. This (and other issues..) was the reason I got rid off SDL and OpenAL and reimplemented it using standard Win-APIs, sometimes you incoparate a lib but only use a very small portion of it ...

But this is only my personal reaction to LGPL licenses. The best advice I could give sofar is, check what library you really need and finally talk to a lawyer.
[/quote]

oh my god why is this so complicated
ok so what is the worst thing that might happen if you use SFML for example and sell your game?

IANAL But have read a few of these licenses (I always do that before I start using them), the worst case with GPL is that you have to open up your source code for everyone to see. If I remember correctly, this happened to a manufacturer of routers a while back.

IANAL But have read a few of these licenses (I always do that before I start using them), the worst case with GPL is that you have to open up your source code for everyone to see. If I remember correctly, this happened to a manufacturer of routers a while back.

None of the libraries use the GPL though, (The LGPL is quite significantly different), the worst case is that you have to release any improvements you made to the libraries themselves or stop distributing the software, potentially you might also have to pay the copyright holder.

The worst thing that can happen though is that he gets sued for copyright infringement, (Most opensource developers are fairly calm about it though and will try to help you comply with the license rather than taking you to court over it, but they do have the right to sue your ass off and will win if you fail to or refuse to comply with the license)