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BigShooter
07-27-2003, 02:13 PM
Hi, I'm a total beginner to OpenGL. I'm in my final years of CS degree, so C/C++ programming isn't new to me. I've tried DirectX and could not stand the ugly syntax, complicated code etc. etc. so coming to OpenGL was very pleasant. However, I'd like to know what are some honest limitations of OpenGL (most recent version) when compared to DirectX?
Thank you,
Luke

JanHH
07-27-2003, 02:31 PM
I think the biggest weakness is rather poor driver support (compared to directx) under windows. However, as there are only very few hardware manufactureres left (nvidia, ati and some more) which provide good drivers, this is rather a small problem.

There are no "limitations" in terms of functionality (afaik), OpenGL is rather better than d3d due to mechanism of extension. In d3d, no additional feature of any great new graphics chip can be used as long as microsoft doesn't include it into d3d, with OpenGL, this is not the case, every new feature can instantly be used.

Also, d3d is limited to windows-only, while OpenGL is a platform independet standard.

And OpenGL is an industry standard /(games, CAD, simulations), while d3d is windows-only and (nearly) games-only, so I honestly think, d3d is not really worth the effort of learning, as long as you do not need it for your job (or REALLY like it).

But this forum and the internt are full of ogl vs d3d articles, so you should find a lot about it and it is not really neccessary to start a new discussion here.

But basically, OpenGL is not WORSE than d3d but rather better.

Jan

JanHH
07-27-2003, 02:32 PM
well but you cannot honestly compare OpenGL to direct _X_, you can only compare it to diretc _3D_, as OpenGL is graphics-only and does not suppurt input, sound etc. There are a lot applications that use both, ogl for graphics and directx for sound, input etc.

BigShooter
07-27-2003, 02:34 PM
Sorry, I meant the Direct3d part of DirectX, not the whole DirectX API :-)
Thanks,
Luke

JanHH
07-27-2003, 02:42 PM
ok somehow I guessed that http://www.opengl.org/discussion_boards/ubb/wink.gif

Jan

starman
07-28-2003, 05:52 AM
Try searching "opengl vs direct3d" here or groups.google.com. This topic has been beaten to death.

JD
07-30-2003, 12:35 AM
I don't know what gl lacks but I can tell you what d3d lacks. It lacks crossbar feature which is important to avoid burning the first texture unit so that you can fit your algo into texture unit paradigm. It seems to me like gl though it might lack some d3d features, makes up for them by targeting hw features that are needed in real world. That crossbar feature is a prime example.

When I ported my d3d app to gl I didn't loose any functionality, infact I gained it and some speed as well.