# OpenGL Open Library

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Has anyone ever thought of making or compiling a Open Game Library similar to Direct X?
OpenAL - for sound
OpenGL - for graphics
RakNet - for networking              (formerly called OpenNL)
GLUT   - for input (?)
GLee   - for extensions (?)

just all in one package ready to use.

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yes, but nobody would agree on what to include.

For instance I'd agree with most of your choices except GLUT (use SDL for windowing an input) and GLEE (I prefer GLEW).

It would be useful as far as marketing and attracting noobs go, but would it provide any actual benefit in use? You could say that it would be nice to package it all together so that it's easy to install and build, but this would make it hard to keep up with latest releases of all components and still make sure it all works properly. The type of people who have a hard time finding and building open equivalents to directx would probably still use directx...

You do have a good point though, it would be easier to attract people (especially existing game studios, who seem to find it very difficult to use anything that doesn't come with the directx sdk) to open / cross platform libraries if there were some apparent common standard.

BTW I think you're thinking of HawkNL not RakNet when you say OpenNL.

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yeah, the lack of agreement would be a problem, for example I'm bias so i'd naturally pick my windowing library to perform window tasks (which includes GLee to make my extensions go), I'd be using Corona for image loading as I prefer to C++ things as much as I can and networking would probably fall to OpenTNL (Torque Network Library).

Others still would want to use FMod or DirectSound/Music/whatever-it-is-this-week for sound, some other image loading library or plain sockets for networking.

While I'm sure it could be done, it wouldnt suit everyone and we'd be back to square one all over again [smile]

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Quote:
 Original post by mrbastardyes, but nobody would agree on what to include.For instance I'd agree with most of your choices except GLUT (use SDL for windowing an input) and GLEE (I prefer GLEW).It would be useful as far as marketing and attracting noobs go, but would it provide any actual benefit in use? You could say that it would be nice to package it all together so that it's easy to install and build, but this would make it hard to keep up with latest releases of all components and still make sure it all works properly. The type of people who have a hard time finding and building open equivalents to directx would probably still use directx...You do have a good point though, it would be easier to attract people (especially existing game studios, who seem to find it very difficult to use anything that doesn't come with the directx sdk) to open / cross platform libraries if there were some apparent common standard.BTW I think you're thinking of HawkNL not RakNet when you say OpenNL.

I see. The curse of OSS. There's 50 versions for one thing. Well, hmmm. Again, I'm brainstorming, isn't there a way for a user to let's say, pick what libraries he needs (like through a menu) and have it just download the libraries for him and install them? Again, brainstorming. But I definitely see your point.

And you're right about NL thing. I didn't mix them up.

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Quote:
 Original post by _the_phantom_yeah, the lack of agreement would be a problem, for example I'm bias so i'd naturally pick my windowing library to perform window tasks (which includes GLee to make my extensions go), I'd be using Corona for image loading as I prefer to C++ things as much as I can and networking would probably fall to OpenTNL (Torque Network Library).Others still would want to use FMod or DirectSound/Music/whatever-it-is-this-week for sound, some other image loading library or plain sockets for networking.While I'm sure it could be done, it wouldnt suit everyone and we'd be back to square one all over again [smile]

unfortunately, we should implement MS type tactics and get some libraries, put on a CD, ship it with a book, and force the user to use it. [grin]

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Having the API in the Library doesn't mean you have to use it. Direct3D doesn't rely on DirectInput, if you get my point.

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Something fun to try [smile]. But would you(not specifically directed) want to have a common name API to be used like DX? Rather than have all the ALint then GLing etc... just one standard?

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Quote:
 Original post by Alpha_ProgDesisn't there a way for a user to let's say, pick what libraries he needs (like through a menu) and have it just download the libraries for him and install them?

You're right - you could use something similar to RPMs or .deb to resolve dependencies but still give the user choices.

In that case though, it might be good to wrap everything in a common API, firstly for the reasons Drew said, but also so that the user doesn't have to learn 10 different conceptual approaches. Abstract the interface from the library thats actually doing the job. Something like Sh, just have differnent back ends that the user can choose. In fact you could also add directx back ends.

This helps with the choice problem, but introduces quite an engineering challenge in itself - providing an abstract interface to all those APIs without sacrificing speed.

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Those are Engines, not really libraries (although, its arguable).

Personally, i prefer the free options...OpenAL for sound (FMOD has a licencing fee when going commercial) etc etc.
Although, most sound Libs (includeing the 2 i mentioned) actually use Direct Sound anyway.

Allowing users to pick what library would be great, but the work involved would be huge, porting sections to use different libs, so probably we should make a standard or something, so that people can make their own compatable sections of the OpenLib (lol, catchy name :P).

-Twixn-

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I have been thinking about it, it would have

opengl
openal
sdl_image
sockets
sdl
(and maybe glee or glew in early versions)

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I've been thinking about what sort of API you could provide to abstract all those different libs, and it occurs to me that Opengl, DevIL and OpenAL already use a similar 'state-machine' style.

On a more general note, I'm starting to think that a centralised resource for getting hold of and learning to use the open libraries is actually more of an issue than providing a common API.

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Bothe DevIL and OpenAL were designed to fit alongside OpenGL...so using them as a kind of DX setup seems natural...(havent tried HawkNL, that probably is too).

I dont think GLUT and GLEE (or substitues) should be counted as separate libraries...they should just be shoved as sub-headings in the OpenGL section..as GLu is, and ALut ALu and ALc are with OpenAL. They are simply extending OpenGL (especially GLEE :p).

-Twixn-

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how about rewriting favorites of glut and sdl and mix them together and maybe i would like the library/api/engine. use sdl for mainly 2d and input use glut for setting up the whole mess.

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I dont see any reason to NOT try to set something like this up, I wouldnt mind setting up a small group that would choose a set of open source libraries to create a "game programming library" (because the next best thing to pleasing everyone is pleasing most lol). PM me if your interested.

cheers
-Dan

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I hope that the The Khronos Group will create an Open Library that would make things much better. We would have a standard created by the industry.

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There have been a few attempts at similar things (one of them by me). ClanLib is somewhat similar, and my old project (the now ultra-defunct and originally 2D only) ZEngine are two such projects that I know of. It does seem to me there are people looking for this sort of thing, I still get a few emails a month from people using ZEngine (which really suprises me, so I figure there truly is a need for this sort of thing or they would have moved on).

Also as far as libraries go, I'd say try to keep them as free as possible, so RakNet is out as is FMod. Keeping the utility libraries as free as possible eases distribution/confusion. I'd recommend nothing more restrictive than the LGPL (and avoiding the LGPL where it can be avoided).

I've played around a lot (and I do mean a lot) with the options, I'd recommend:
OpenGL for graphics
OpenAL for audio*
GLFW for input/window management
GLee for extensions

*I'm not a big LGPL fan, but OpenAL is LGPL, and there aren't many other options.

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