SDL 2.0 Has Been Officially Released

[computerquip]

It says that because 3.x is the most common to be used in modern games. If you look at a video cards specifications, you'll often see that it boasts 3.3 support without mentioning 4.x at all. Haswell does this and AMD does this.

[stqn]

I'm aware of all of that, and wasn't the point. I thought it was implicit that I meant on closed source programs (i.e., most mainstream games), and without any extra requirement on your program, with the obvious exceptions of publishing any changes you did to the library.

Sorry for not being a mind reader.

[mrugiero]

Sorry for not being a mind reader.

Didn't expected you to, as I said, I thought it was clear, it was obviously not, and that's what I tried to say. I thought it would be obvious by context, and it wasn't, just that.

EDIT: Actually, I read it again and it seems quite obvious for me. I mean, if I stated that zlib allows you to keep the changes you do as closed source, and that's why I said I thought that was a poor license choice for this case, logically it's assumed we are talking about closed source programs (why would you keep the changes on the library closed, if you publish the code of the whole program?), and that I don't want the possible changes on the library to be closed (since, otherwise, zlib would actually be the best license for that). LGPL fulfills the latter, but doesn't allow the closed source programmer to link statically.

[alanc]

Is there any license that has copyleft but allows static linking? I see zlib (along any liberal licenses) as a poor choice for SDL, since it allows to keep changes closed.

Yes, Mozilla Public License (MPL) allows that, as do MPL derivatives like CDDL.

[mrugiero]

Yes, Mozilla Public License (MPL) allows that, as do MPL derivatives like CDDL.

Did anyone stated why they didn't go with that license, if they just wanted to allow static linking?

[Kristian Joensen]

Didn't expected you to, as I said, I thought it was clear, it was obviously not, and that's what I tried to say. I thought it would be obvious by context, and it wasn't, just that.

EDIT: Actually, I read it again and it seems quite obvious for me. I mean, if I stated that zlib allows you to keep the changes you do as closed source, and that's why I said I thought that was a poor license choice for this case, logically it's assumed we are talking about closed source programs (why would you keep the changes on the library closed, if you publish the code of the whole program?), and that I don't want the possible changes on the library to be closed (since, otherwise, zlib would actually be the best license for that). LGPL fulfills the latter, but doesn't allow the closed source programmer to link statically.

:

v3:

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and:

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v2.1:

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and:

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Edit:

MPLv2 can be GPL compatible but is not clear to me that it would have that effect on SDLv2. I will have to rre-ead that part of it. The SDL guys probably want allow both GPL AND propietary game and applications to use SDL. It seems MPLv2 would allow static linking with BOTH GPL AND proprietary software.

[stqn]

The MPL seems interesting indeed, as a middle ground between MIT/BSD/zlib and GPL/LGPL. Thanks for mentionning it.

[mrugiero]

:
Licenses quotes.

Let's see the practicality of all of that, and why I simply disregard it. Think how much a game weighs, how much the library weighs, and then think of the weight of the final package you will distribute, because of an object file that will go unnoticed for years, until someone actually needs to relink. The sacrifice is higher than the gains, there. That's why I disregard them as "doesn't allow linking statically in closed source apps". I mean, it will take almost twice the disk space, for something few will use. This means twice the media discs or twice the download time. Distributing the source code of the library is reasonable, but an object file that represents almost the whole program PLUS the usable program is another thing.

On the intention, that's what I understand they wanted, but they went with a liberal license that allows modifications to not be distributed as source code, instead of one that simply allows linking statically.

[icculus]

Hey there, just going to fill in a few answers in one post here.

No OpenGL 4.x support? It sounds bad. Is it in the short term plans?

4.x works. I thought "3.0+" was understood to mean "3.0 or later." Sorry if that wasn't clear.

It's largely notable because 3.0 is when you started having to explicitly ask for a OpenGL version to get a "core" profile or whatnot. SDL supports all that now.

Did anyone stated why they didn't go with that license, if they just wanted to allow static linking?

Among other reasons we really like zlib, you can read it in about 30 seconds and understand it without being a lawyer. The MPL definitely doesn't fit that requirement.

It wasn't important to us to force people to publish their changes. We appreciate when they do, but if they don't, oh well.

With games statically linked to SDL2 created if the coming years, I expect then to be completely lost (i.e. to be impossible to execute) in ten years.

This is more likely to be true on Linux/Unix--less so on other platforms--but my hope is that people shipping Linux titles understand this enough to not statically link SDL, and/or will get enough shit from Linux users right away to understand they need to treat static linking as a bug. It's worth noting, though, that the zlib license lets you pull a useful function out of SDL2 and paste it into your program without all sorts of legal concerns, and static-linking the whole library aside, that's a good feature, too.

Still no option to make an sRGB context?

This is definitely landing in 2.0.1; there's a patch sitting in Bugzilla right now to implement this here. Note that this only gets you Windows and X11 support...nothing else has the sRGB-capable bit thing yet, as far as I know.

[mrugiero]

Among other reasons we really like zlib, you can read it in about 30 seconds and understand it without being a lawyer. The MPL definitely doesn't fit that requirement.

It wasn't important to us to force people to publish their changes. We appreciate when they do, but if they don't, oh well.

Thanks for the clarification. I assumed otherwise because of the previous license choice (LGPLv2 or GPLv2, I'm not sure).