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subnet_rx

OpenGL Newer OpenGL API?

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I have downloaded Dev-C++ and started learning OpenGL. The readme.txt in the OpenGL section says that the gl files are from Windows 95. Do I need newer versions of these files? I''m working on a NT ServPack 6 system. If so, where can I get them? I can only access the internet through a browser, so I don''t think the GLsetup.exe is going to work. subnet_rx

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Microsoft hasn''t released a new OpenGL MCD for Windows in ages, so you probably have the newest. What you do probably need, however, is the newest OpenGL drivers for your video card (for NT, of course). GLsetup just automatically detects and then installs the detected video drivers anyway.

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quote:
Original post by subnet_rx
Ahh, so eventhough my video drivers are OpenGL 1.3 compatible, the API is the same as was in 1.1?

In Windows, yes. If you read the OpenGL ARB notes, they have been mad at Microsoft for not updating the MCD for a while. SGI offered to write it for them, but Microsoft wants to ship their personal updated MCD with Windows (if any at all). I''m not sure, but I think SGI already wrote one for Windows. Most other OS''s have an OpenGL 1.2 (if not 1.3) implementation already. This is sore point of mine, in case you haven''t noticed .

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quote:
Original post by subnet_rx
so, how would you implement the 1.3 specification yourself? Or is all OpenGL games in Windows running under 1.1?

They all technically run in OpenGL 1.1, but they can call features that were standardized in 1.2/1.3 through extensions.

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In Linux, is the latest MESA 4.0 compliant with the OpenGL 1.3 API?

I''m still a little confused as to the difference between using MESA vs. OpenGL. I realize that the syntax is the same, so is the difference mostly legal? I.e., I don''t need to procure a license to distribute a game?

I''m also wondering if I use certain game SDK''s such as ClanLib if it can be used with MESA. In other words, wherever I can use OpenGL I can use MESA as it is transparent to the system?

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ok, the way I understand it is. The OS makes a platform available for OpenGL. In Microsoft Windows, Microsoft makes OpenGL available, in Linux, MESA makes the libraries available. Apparently, MESA keeps up with the OpenGL specification, MS does not.

subnet_rx

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Guest Anonymous Poster
> I''m not sure, but I think SGI already wrote one for Windows

I already heard that several times. Does anybody know, where to get this SGI implementation ?

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quote:
Original post by Dauntless

I''m still a little confused as to the difference between using MESA vs. OpenGL. I realize that the syntax is the same, so is the difference mostly legal? I.e., I don''t need to procure a license to distribute a game?

I''m also wondering if I use certain game SDK''s such as ClanLib if it can be used with MESA. In other words, wherever I can use OpenGL I can use MESA as it is transparent to the system?


Hi,

Mesa is work alike for opengl but its not opengl itself.

Regarding license you might want to look at this link.
http://www.opengl.org/developers/license/license.html

By the way games fall into the application area.

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Mesa is really a OpenGL implementation with a different name. You do not have to worry about any license. I think that compiling Mesa yourself so it will take advantage of hardware acceleration (DRI) can be difficult.

If your version is 1.3 do you also have software implementations of functions that your card does not support. The difference between the extensions and software core functions is speed (surprised ) and often other limitations like just smaller textures being supported. I would say you are using 1.3 but you have to get entry points for core functions the same way as for extensions.

Intel made a little library that will make using the latest version and extensions a little easier special on Windows. It is available here
http://oss.sgi.com/projects/ogl-sample/sdk.html

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Guest Anonymous Poster
> Intel made a little library that will make using the latest version and extensions a little easier special on Windows

Intel ? You mean SGI

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Guest Anonymous Poster
Hmm, isn''t that funny, everybody always talks about those ''newer SGI libs'', but no one seems to have them or be able to point to a D/L location.

I''m starting to believe, that all this is nothing but a myth, used by Windows OGL programmers to justify their lack of recent OGL support when talking to Linux/Irix/Mac/Solaris users.
aka:

Linux_User: ''Hey, look, I''ve a nice OGL app. Do you want the source ?''
Windows_User: ''Sure, it looks good, and with minor modifications, I''ll compile it under MSVC++ !''
Linux_User: ''No, you won''t. It uses recent technology. OGL 1.3. You Windows users only have access to the obsolete 1.1 version due to Microsoft-stupidity''
Windows_User: ''Hmmm.. yeah I know,.. but.. uh.. uhm.. *cough*.. SGI is making an OGL 1.3 release !!''

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I'm not aware of any SGI version of OpenGL 1.3 for Windows, but at one point SGI *did* write their own OpenGL implementation, back in the 1.1 days. It was significantly faster than Microsoft's OpenGL implementation when doing software rendering..But then A) everyone got 3D hardware, making the software rendering speed pretty meaningless (and it was still pretty slow if you did anything complex, just a lot faster than MS's software rasterizer) and B) Microsoft and SGI joined forces on Farenheit, a set of 3D APIs which were supposed to replace D3D and OpenGL, with both immediate and scene graph mode (Like the old D3DRM) APIs. Farenheit fell apart sometime a year or two ago and nothing much came of it. IIRC Microsoft did eventually release the scene graph part of Farenheit to a limited audience, but I havent heard anything about it in a long long time so I'm guessing they killed that off too.

I just did a quick google search and it looks like you can still get the SGI OpenGL SDK here:

http://www.berkelium.com/OpenGL/

Its completely unsupported though (and hasn't been supported since Windows 95, IIRC) and it has a few major known bugs that cause crashes. So all in all you don't want to use it.




If SGI does have a new 1.3 implementation, I haven't seen it. And yes, it is rather annoying that Microsoft has been dragging their feet so much on OpenGL. And its clearly all political (make OpenGL look dead on Windows to try and get more support for D3D).



Edited by - gmcbay on December 21, 2001 5:04:33 AM

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Umm us windows opengl coders have no problems accessing the 1.3 features.

As for the SGI libs, from what Ive heard, microsoft refuses to let them release the libs, most likely in a vain attempt to get more people using d3d.

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Guest Anonymous Poster
> Umm us windows opengl coders have no problems accessing the 1.3 features.

No, you have to do it via extensions. Not all features are accessible that way, and even worse, it isn''t compatible with legacy 1.3 code.

> As for the SGI libs, from what Ive heard, microsoft refuses to let them release the libs, most likely in a vain attempt to get more people using d3d.

Microsoft can not stop anyone releasing OpenGL libs. Especially not SGI, since they developed OpenGL, and have all the rights, patents (if there are any), and trademarks. Releasing OGL libs doesn''t involve *any* M$ source. See Mesa.

I just don''t believe that SGI has actually written 1.3 libs for Windows. It''s more likely it is a ''Windows OpenGL user justification legend''.

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Guest Anonymous Poster
Ok, guys.

SGI has written only one OpenGL implementation(v 1.1) for windows in year 1995.
There doesn''t exist any implementation of v1.2 , not saying v1.3
for Windows.
All functions of v1.2, v1.3 must be querried by glGetProcAddress as extensions.
Intel(Intel, not SGI!!!) has written a library, something like GL... howewer, I forgot. Idea is that this library is querring v1.2 funtions for you.

Best wishes.

Zengar.

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