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SuperRoy

OpenGL A few basic OpenGL Questions

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SuperRoy    109
Hey, my interest in OpenGL has grown since the last time I''ve programmed something. I''ve got a few questions about OpenGL. I hope you don''t mind. 1) How long did you program in C or C++ before learning OpenGL? 2) What did you use to learn OpenGL? How long did it take you? 3) Are TGA files the norm for textures? I see them often used. 4) What do you use for input and sound? 5) What do you think the advantages of OpenGL are? The Disadvantages? Thanks a lot, --Andrew

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Null and Void    1088
quote:
Original post by SuperRoy
1) How long did you program in C or C++ before learning OpenGL?

A while. Actually about 5 years or so. It doesn''t matter "how long" as much as "do you know the language?".
quote:
Original post by SuperRoy
2) What did you use to learn OpenGL? How long did it take you?

NeHe''s tutorials were enough to get me started. After the first 6 or so I was able to learn from documentation (SUN has some nice OpenGL documentation on their site).
quote:
Original post by SuperRoy
3) Are TGA files the norm for textures? I see them often used.

The Targa format is very adaptable. Supporting an alpha channel while still being really easy to load make it a good choice.
quote:
Original post by SuperRoy
4) What do you use for input and sound?

SDL and possibly OpenAL.
quote:
Original post by SuperRoy
5) What do you think the advantages of OpenGL are? The Disadvantages?

It''s #1 advantage is portability. I don''t really see many disadvantages in it; it does exactly what it''s meant to without being bloated or otherwise encumbered.

[Resist Windows XP''s Invasive Production Activation Technology!]

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ZealousElixir    256
quote:
Original post by SuperRoy
1) How long did you program in C or C++ before learning OpenGL?


hmm. About a year before I really got into it. Before I did C/C++, I did a lot of QBASIC, which hurt more than helped.
quote:

2) What did you use to learn OpenGL? How long did it take you?


I started OpenGL with NeHe, read about 8 tutorials, and got sick of it, mostly because I pushed too hard. About 4 months ago, I got OGLGP, and that was the impetus for a learning streak that is still continuing.
quote:

3) Are TGA files the norm for textures? I see them often used.


Targa files are desirable because they allow for a built-in alpha channel, they are small compared to BMPs (I'm not actually sure about that), and they're easy to load. I don't know if I'd say they're the norm...PCX and BMPs are still in wide use.
quote:

4) What do you use for input and sound?


>_< DirectX. I really should learn SDL, but I'm lazy.
quote:

5) What do you think the advantages of OpenGL are? The Disadvantages?


Advantages are: cross-platform (don't all you DX maniacs tell me I'll never develop for Linux...you don't know that.), fast, small, so many other things....
Disadvantages? Almost none except you're hated by D3D afficianados.

Hope that helps,
ZE.

EDITED for grammatical issues.

Edited by - ZealousElixir on December 16, 2001 9:36:33 PM

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Guest Anonymous Poster   
Guest Anonymous Poster
1) I started programming with C for about 2 years before starting OpenGL, and changed to C++ about 6 months ago.

2) I used the NeHe tutorials and the red book (OpenGL Programming Guide). I am still in the process of learning.

4) I use SDL and OpenAL for input and sound.

Also, check out a scenegraph(eg. www.openscenegraph.org), which automates many functions such as model and image loading and efficient culling of objects out of view.

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