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badblood909

OpenGL How is OpenGL related to SDL?

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I am sorry for this totally n00b question, but whenever I read something related to OpenGL around the net, SDL was sure to follow, even in the forum FAQ, and thats why I ask my sorry-arse question. Also, is GLUT OpenGL in the same line of say, ANSI C? Meaning that it would work under any platform? In OpenGL.org, I did not find what I should download to be able to run OpenGL programs on my Linux system, and OpenGL books that I saw all come with software for the MACos and Windows, no Linux, is there any book that I missed? All help apreciated, thank you for your time. -It''s all in the blood...

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quote:
Original post by badblood909
I am sorry for this totally n00b question, but whenever I read something related to OpenGL around the net, SDL was sure to follow, even in the forum FAQ, and thats why I ask my sorry-arse question.

There is no direct relationship. SDL is available on many different platforms, like OpenGL, and it can be used with OpenGL. That''s it.
quote:
Original post by badblood909
Also, is GLUT OpenGL in the same line of say, ANSI C? Meaning that it would work under any platform?

GLUT''s available on most platforms... I believe every platform that OpenGL is available on. It''s primary purpose is to wrap OS-specific code, so that usually, code written using GLUT can be compiled on most platforms with no changes.
quote:
Original post by badblood909
In OpenGL.org, I did not find what I should download to be able to run OpenGL programs on my Linux system, and OpenGL books that I saw all come with software for the MACos and Windows, no Linux, is there any book that I missed?

I don''t know what you need to download to use OpenGL on Linux, but I thought that OpenGL.org had some links.

As for books, I know that Linux Game Programming covers some OpenGL. There''s also OpenGL Programming for the X Window System.

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To run and compile OpenGL programs under linux all you need is to download both GLX and Kernel drivers for 3D card, all GL-includes will be installed then.
if you have an NVidia chips have a look to :
http://www.nvidia.com/view.asp?PAGE=linux

you can use GLX as window manager, it has the same function than WGL under windows. But SDL or GLUT are more simple to use.

sorry for the double post...

[edited by - hanibal_smith on April 30, 2002 1:26:19 PM]

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quote:

There is no direct relationship. SDL is available on many different platforms, like OpenGL, and it can be used with OpenGL. That''s it.



Well, not quite it. SDL has direct support for OpenGL. It''s an extremely easy way to build an OpenGL app.

Which actually raises a question for me about SDL. I like it, it does everything that I need it to do, with a fraction of the complexity of DirectX. The cross-platformness is a nice benefit.

What are the downsides of SDL? Why is it (along with ClanLib and Allegro, neither of which I''ve messed with) considered useful for "beginner" projects, but not for serious work?

Thanks!

Take care,
Bill

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quote:

What are the downsides of SDL? Why is it (along with ClanLib and Allegro, neither of which I''ve messed with) considered useful for "beginner" projects, but not for serious work?



Well, for one, SDL wouldn''t be able to acess all the hardware specific, or feature specific, functions that DirectX might be able to handle. Since it is a cross-platform library, every function has to work on ALL platforms, and obviously, not all graphics features are available on all platforms.



"I am governed by none other than the Laws of the Universe."

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quote:
Original post by badblood909
In OpenGL.org, I did not find what I should download to be able to run OpenGL programs on my Linux system, and OpenGL books that I saw all come with software for the MACos and Windows, no Linux, is there any book that I missed?

All help apreciated, thank you for your time.

-It''s all in the blood...


Even if you had a really old version of Linux, chances are, if you do a locate or find for GLU.h or GLUT.H, you should find them installed somewhere. At least, if you set up your distro for coding(ie: the best setup for any user even those who don''t plan on coding. )

As for books, get any book that talks about OGL and the code should(you might need to tweek it a bit but hey, that''s part of the programming fun... ) compile on Linux.


"And that''s the bottom line cause I said so!"

Cyberdrek
danielc@iquebec.com
Founder
Laval Linux

/(bb|[^b]{2})/ that is the Question -- ThinkGeek.com
Hash Bang Slash bin Slash Bash -- #!/bin/bash

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quote:
Original post by Hanibal_smith
To run and compile OpenGL programs under linux all you need is to download both GLX and Kernel drivers for 3D card, all GL-includes will be installed then.
if you have an NVidia chips have a look to :
http://www.nvidia.com/view.asp?PAGE=linux

you can use GLX as window manager, it has the same function than WGL under windows. But SDL or GLUT are more simple to use.

sorry for the double post...

[edited by - hanibal_smith on April 30, 2002 1:26:19 PM]


You don''t even need that, it''s mostly the drivers for your card which are incredible by the way, they work wonders. I have''em installed on my Linux box. As for what I was saying, most linux distros already have the libs and includes for OGL.



"And that''s the bottom line cause I said so!"

Cyberdrek
danielc@iquebec.com
Founder
Laval Linux

/(bb|[^b]{2})/ that is the Question -- ThinkGeek.com
Hash Bang Slash bin Slash Bash -- #!/bin/bash

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quote:
Original post by i8degrees

Well, for one, SDL wouldn''t be able to acess all the hardware specific, or feature specific, functions that DirectX might be able to handle. Since it is a cross-platform library, every function has to work on ALL platforms, and obviously, not all graphics features are available on all platforms.




Wrong dude, as already mentioned, SDL wraps DX on Windows systems and OGL on Linux systems. So basicly, you could use SDL for serious game programming. BTW, Loki used SDL for some of their ports of Windows games( or was it for all of them? I don''t remember ). So SDL could be used for Serious Game programming as the original poster calls it.



"And that''s the bottom line cause I said so!"

Cyberdrek
danielc@iquebec.com
Founder
Laval Linux

/(bb|[^b]{2})/ that is the Question -- ThinkGeek.com
Hash Bang Slash bin Slash Bash -- #!/bin/bash

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quote:

Wrong dude, as already mentioned, SDL wraps DX on Windows systems and OGL on Linux systems. So basicly, you could use SDL for serious game programming. BTW, Loki used SDL for some of their ports of Windows games( or was it for all of them? I don''t remember ). So SDL could be used for Serious Game programming as the original poster calls it.



SDL wraps OGL on Windows also. It uses DX for everything else(input, sound, etc).

I''ve done some DX programming, and had to write wrapper classes to avoid constantly rewriting all the tedious DX setup junk. And my wrapper classes ended up looking very similar to SDL. So for me, SDL does what I would want a wrapper library to do, and I get portability for free.

I don''t think that Loki is a good example of the use of SDL. They made good ports, to be sure, but only on Linux. I''m wondering why a major studio doesn''t use SDL to target more than one platform. Or even use SDL for a windows only project.

Take care,
Bill




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SDL is good for many reasons. Some of them are:

It's a cross platform API.
It's open source.
It gives you full access to OpenGL (some minor differences are initialization and flipping buffers)
It's used (and developed) by a lot of people, which means it's relatively bug free.
It's updated often.
It's a much better wrapper for DirectX than you can ever write
It has a function for generating decaf coffee and bagels with cream cheese.

It really is a good API though. It even has its own multithreading wrappers and timers. I don't know why big companies don't use it, maybe it's because they don't care about other platforms and/or want to use Direct3D. There is one problem I encountered with SDL which is supposed to be fixed soon, and that's the mouse wheel scrolling isn't working very well. Other than that I have no complaints.

[edited by - Supernova on May 1, 2002 12:25:51 PM]

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>>It gives you full access to OpenGL (some minor differences are initialization and flipping buffers)<<

the reason for this is so u can support voodoo cards (1,2,3) without having to change your code, in the old days this was a major pain

http://uk.geocities.com/sloppyturds/gotterdammerung.html

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antistuff you''re pretty much right. The difference is that you have to tell SDL you''re using OpenGL, and then use SDL buffer flipping function instead of OpenGL''s because SDL has access to the window internally. In other words you don''t know the handle of the window only SDL does, so you have to let it take care of some OpenGL init and the buffer flipping.

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