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Daivuk

OpenGL Open Graphics Librairy

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Does the word "open" supposed to mean "OPEN SOURCE"? I cant find any source code of opengl over the net :| I mean, THE code of opengl :P I know thats probably a stupid question, but I was thinking about this. If openGL is open source, I was cusious to get a look to the code. :P

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OpenGL isn't really open source because it's not an application. OpenGL is actually just a bunch of fuction and enums, etc. that an OpenGL implemetation has to have. The one that you are most likely using is one that isn't open source. However if you want to see the source code to one that is, then look at Mesa.


EDIT:Just in case you want to use Mesa, you should know it is not software accelerated.

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"Open" in OpenGL does not mean open source. OpenGL is an API, while .dll and .lib are implementations. The "open" in the case of OpenGL means that the API can be implemented by who ever wishes to do so (with some limitations).

There is an open source sample implementation to OpenGL provided by SGI (google SGI OpenGL sample implementation to find it), but that does not contribute the name of the API.

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Quote:
Original post by Vampyre_Dark
Implenters have to pay a licensing fee I think.


ok, soo. opengl is the property of someone? :P
I didnt know that. I have learned something today :P thanks

I was thinking that opengl was like linux. Open Source and everyone can modifiate it or create extension.

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OpenGL is just a specification. It is up to others to provide the implementation. In the case of hardware accelerated OpenGL, the implementation is normally provided by the manufacturer of your graphics card, and comes as part of your drivers. In this case, the source code is most definitely _not_ open, since the hardware guys like to protect their stuff.

There is an open source implementation of OpenGL, called Mesa (google it), which provides source code. It's a fairly high quality implementation, and though it is mostly software only, there are some instances in which hardware acceleration may be applied. (IIRC). I believe it implements up to version 1.5; it may go further, I don't know. Been awhile since I looked it.

At any rate, if you're curious as to how one implementation of OpenGL is done, you can look at Mesa. It probably won't tell you a whole lot about how vendor-provided implementations are built, though...

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Quote:
Original post by Vampyre_Dark
It means open standard. And it's only free to coders. Implenters have to pay a licensing fee I think. (See Opengl.org faq)

You have to pay a license fee if you want to call it "OpenGL". You're free to implement a library that follows the standard, but without the naming, and you won't have to pay a cent.

Quote:
Original post by Daivuk
ok, soo. opengl is the property of someone? :P

The trademarks on the name and the logo are property of SGI (formerly Silicon Graphics). There is an official commitee, the ARB (Architectural Review Board) consisting of major implementors. They decide over the future direction of the standard.

Quote:
Original post by Daivuk
I was thinking that opengl was like linux. Open Source and everyone can modifiate it or create extension.

OpenGL is no software, it doesn't have any source. You're free to implement your own version, just don't call it OpenGL. And you can definitely create an OpenGL extension, and submit it to the registry. Actually, you could even theoretically get onto the ARB, if the current members agree (which is a practical limitation of course, you need a lot of reputation, money, and market power to get onto it).

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