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Fonz

OpenGL What can be used to complement OpenGL?

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Hey, I''ve been looking at game programming for a while now and Im starting to feel its time to move on from text based games. I know how to use OpenGL to some extent. I was wondering what other open source librarys are out there for sound etc? Something to go with OpenGL. I gave directX a good look over but the more I look into it the more detered I get. plus I''ve heard OpenGL is faster. cheers, Fonz

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OpenGL is not faster. You gotta be careful you don''t start a flame war...

To answer your question, here are a few good libraries to compliment OGL:


SDL: This has sound, input, windowing/GUI functions, and probably quite a few other nifty things.

OpenAL: An audio library made to be similar to OpenGL in ease of use and functionality.

HawkNL: The Hawk network library, for all you''re networking/multiplayer needs.

DevIL: This is a good image loading library, so you don''t have to write you''re own BMP/TGA/JPG/etc loader. Very handy.

I think that should cover all the bases. Hope it helps!

--Buzzy
(formerly buzzy_b)

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Buzzy covered the basics, but I just want to add FMOD for sound. It seems to have more support than OpenAL, better documentation (I figured out FMOD by looking at the function declarations... I looked through the OpenAL docs and it appeared to be much more complex). It doesn''t used an OGL-like syntax, but it is easily configured.

In case your interested, I posted a sample FMOD MP3-playing code a few weeks ago in this thread:
http://www.gamedev.net/community/forums/topic.asp?topic_id=102851

And I am also currently using DevIL for image loading. Really handy, and it has an OGL-like syntax.

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quote:
Original post by Erunama
Buzzy covered the basics, but I just want to add FMOD for sound. It seems to have more support than OpenAL, better documentation (I figured out FMOD by looking at the function declarations... I looked through the OpenAL docs and it appeared to be much more complex). It doesn''t used an OGL-like syntax, but it is easily configured.



OpenAL probably has more flexibily in the long term than FMOD (you can work your sound system to your needs), but FMOD is probably perfect if all you want to do it play back a few sounds etc.

OpenAL was used with Solider of Fortune 2 and will be used in the up and coming UT2K3 (at least, as far as all the info I''ve seen on it says *koff*2leakeddemos*koff*) so it cant be bad at all

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quote:
Original post by Fonz
What can be used to complement OpenGL?



Well, she likes words like efficient, nicely written, elegant, easy to use, and fun. =D

(sorry, I had to. =D)

-=Lohrno

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quote:
Original post by smarechal
Altho many people don''t like it, I use DirectSound and DirectInput in conjunction with OpenGL. Works for me



OpenAL pretty much sits over the top of DirectSound on Windows anyways I belive, but it allow for the code to be more portable, granted if being portable isnt important to you then its not a problem

As for input, aside from directinput or SDL are there any other libs for input?
a X-platform standalone input system might be worth while someone making (I know one exists in SDL, but having one to use apart from that might be handy)

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quote:
Original post by _the_phantom_
a X-platform standalone input system might be worth while someone making (I know one exists in SDL, but having one to use apart from that might be handy)

The problem with making an input library is that most systems bind the input to the ''window'' of a program too much. SDL gets around this because it creates the ''window'' as well. I''ve thought about portable input libraries a lot, and I couldn''t see how one could be made standalone.

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IMO, GLUT provides adequate input support for Keyboard and
mouse. So if you use GLUT, then go for it.

It''s strange that OpenIL was "forced" to rename to DevIL and
OpenNL "voluntarily" renamed to HawkNL.

I believe there''s a group working on OpenML (Open Media Library)
that focuses on things like playing movies like AVI,MPG,MOV...

I''d like to try OpenAL myself, but the documentation could
be better. Does anyone know a good tutorial on using OpenAL?


~~~~
Kami no Itte ga ore ni zettai naru!

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quote:
Original post by tangentz
IMO, GLUT provides adequate input support for Keyboard and
mouse. So if you use GLUT, then go for it.



But if your not using GLUT you could well have a problem.

quote:

It's strange that OpenIL was "forced" to rename to DevIL and
OpenNL "voluntarily" renamed to HawkNL.



it might have been because when it was OpenIL the logo looked very much like OpenGL's so they was asked to change it for that reason, maybe the OpenNL ppl got wind of it and desided to change before they got noticed, who knows

quote:

I believe there's a group working on OpenML (Open Media Library)
that focuses on things like playing movies like AVI,MPG,MOV...



yep, i belive alot of ppl who are involved with the ARB and OpenGL are also part of this

quote:

I'd like to try OpenAL myself, but the documentation could
be better. Does anyone know a good tutorial on using OpenAL?



http://www.dev-gallery.com/programming/openAL/main_openal.htm
and
http://www.gel.ulaval.ca/%7Edumais01/genu/tutorials/AdvanceTutorial2.html
are the only two tutorials I know of, dunno how good they are coz I've not hard a chance to read them yet

[edited by - _the_phantom_ on July 17, 2002 8:09:24 PM]

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Hey,

I''ve had a little experience in using GLUT.. Is there any reason not to use it in game programming? Ie. For opening windows etc?

(I know stuff like drawing cubes etc. in glut would slow it down)

cheers,
Fonz

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Fonz

the topic arisen by you is very interesting thanks to you and to all members who provided very useful informations, but I must say I was disappointed about your last sentence.

....gave directX a good look over but the more I look into it the more detered I get.

What are you saying?
Please do not start a flame war again, also you are definitly wrong
the learning curve is more or less the same , let''s say 3-4 months to get reasonably familiar with opengl and no more than 5-6 years...pardon...5-6 months ,with direct x

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quote:
Original post by AlbertoT
but I must say I was disappointed about your last sentence.

....gave directX a good look over but the more I look into it the more detered I get.

What are you saying?
Please do not start a flame war again, also you are definitly wrong


aside from Buzzy you was the only person to pass comment on his mistake about OGL being faster, he didnt ''start a flame war'', me said what he''d heard and he was corrected, your reply was more imflamtory than his imho, so my advice to you is think before you reply like that in future, as I dont belive that section was called for at all.

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Hey Sorry,

If Id known that what I said could have caused a flame war I wouldnt have said it.

Sorry to everyone who took offence, I now know they run at about the same level.

Cheers,
Fonz

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actually he is definatly wrong. in most cases opengl and d3d result in the same speed on most cards since the driver support is pretty decent now for both apis.

anyhoo, just some info for you.

1. you can use dsound, dinput, dshow, etc with opengl. carmack does (dsound and some dinput), as do many other coders.

2. almost all cross platform apis simply are wrappers to directx (ussually just dsound and dinput, though SDL wraps directdraw as well) when being used on a win32 platform.

3. EVERYONE on windows pc used for multimedia has directx and opengl drivers/libraries installed. SDL, openAL, and others require you to either distribute the library (ussually quite small since after all its just wrapping dx) or have them install it.

4. ANY api under GPL requires you to release your code under GPL if you link to the code. this is why most opensource apis tend to be LGPL, make sure you check the liscence. (SDL is definatly LGPL).

5. directx is a viable solution, though much more OOP then opengl. this is the reason some coders find directx confusing.

6. Opengl cant do sound, networking, input, etc. its merely a 3d graphics api thus has no bearing on anything compared to dx. directx is a full multimedia api. you dont have to use d3d to use directsound. you cant use opengl and expect cross platform sound from it. you need would need another library. its quite ignorent for ppl to bash dx and even suggest opengl is faster then dx. when opengl cant do most of the stuff dx can simply becuase the 3d graphics is only a portion of directx. d3d and opengl are comparable speed and feature wise. some perfer OOP and more low level (ie its part of the OS thus it had the ability to query graphics modes, change resolutions/color depth, query/enumerate multiple display devices, etc) access of d3d others perfer the cross platformness and procedural state machine of opengl (resolution switch is OS dependent thus you have to use OS specific calls to switch resolution, there is no openGL call to switch/enumerate resolutions support by the device).

point 6 is merely informative to allieviate confusion. i use both d3d and opengl since i feel they are equal though sometimes opengl for insatnce has better support for certain more advanced hardware features (ie nvidia combiners are slightly more flexible then d3ds shaders since the shaders are hardware independent while the combiners are nvidia cards only through an extension). d3d is nice for those crazy dshow mulitmedia apps since its a bit easier to get dshow rendering to a d3d texture. its also more OOP which fits my coding style better.

it depends on the coder behind the app, not which api is used.

[edited by - a person on July 18, 2002 12:06:53 AM]

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quote:
Original post by a person
4. ANY api under GPL requires you to release your code under GPL if you link to the code. this is why most opensource apis tend to be LGPL, make sure you check the liscence. (SDL is definatly LGPL).



I guess OpenAL is LGPL as I''ve not seen source for SoF2 or UT2K3 about the place

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OpenAL is all well and good, but I have discovered a problem with it . If you use 3D sounds with it, and try to load more than 32 3D sources at once, it decides to stop generating sources, and you start running into problems (even if your sound card supports more than 32 hardware channels). This means that you have to decide manually which 32 of all your sources are most important and then play them, but this can generate more problems. Thats why I switched to FMOD. Also, it only contains a loader for PCM wave files, while FMOD supports many different formats. I will probably go back to it in the future and try to make a really good wrapper, but not at the moment, just thought that I should warn you.

- Weasalmongler

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I think part of the point of OpenAL is that you decode your own audio and pass PCM data to it (I''m pretty certain UT2K3 uses ogg decoding and probably passes PCM data to OpenAL)

As for the 32 sound channels, that could just be a restriction of the compiled verison you have or maybe DirectSound related, I''ve not had a chance to look at that althought I''ve heard about it before now, just means you have to do sound management for yourself.

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quote:
Original post by Anonymous Poster
is there a library like devil but for 3d object formats?


That''s a tough one. I don''t think such a library would work
very well, if it exists. How should the objects be represented?
It''s intimitely tied to the engine that you use.

Have a look at Ogre or OpenSceneGraph.


~~~~
Kami no Itte ga ore ni zettai naru!

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