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OpenGL Future of OpenGL: The future of us all

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Sooo... not long ago when I started doing things with hardware accelerated graphics, I chose OpenGL. Natural decision, I suppose. I bought a book on Direct3D way back when and a book on OpenGL. There were so many things that seemed easier/common sense about OpenGL. Even so, back when I bought those books, OpenGL was far superior. As of late I'm a bit behind the wagon on this one - I want to start playing with more of the advanced technologies (until recently I have used OpenGL to nicely render my experiments with various graphics algorithms, such as the construction of my particle system... those sorts of things). So, it's time to make a decision. Do I need to take the plunge and dump OpenGL for Direct3D simply because D3D is now superior? I've told myself time and time again that OpenGL 2.0 (when/IF it ever gets here) is going to blow D3D out of the water once again. I think many of us tell ourselves that. But the question remains: what IS the status of OpenGL 2.0? What is going to happen to OpenGL 2.0 given that Microsoft is never going to support it in Windows? Also - since I'm really a noobler to the more advanced extensions, I'm baffled by what so many people continually tell me about them. Right now extensions from OpenGL 1.2/1.3 I have been using manually. So uhm... I will continue to be able to do that for OpenGL 2.0, right? See I'm not clear on this. I would like to be - but I can't find any information on it to save my life! Would someone in the know - throw me and nooblers like me a bone - Should I abandon all hope of cross platform engines and D3D-free simulations? Thank you... PS. Sorry if this should have gone in the Beginner's form. It was so OpenGL specific that I figured maybe it should be here :/ [edited by - xori on November 17, 2003 4:34:26 AM]

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[disclaimer]
I''m not interested in joining a flamewar, even though this thread may be asking for it. I''m simply trying to give useful advice.
[/disclaimer]
quote:
Original post by Xori
Sooo... not long ago when I started doing things with hardware accelerated graphics, I chose OpenGL. Natural decision, I suppose. I bought a book on Direct3D way back when and a book on OpenGL. There were so many things that seemed easier/common sense about OpenGL. Even so, back when I bought those books, OpenGL was far superior.

As of late I''m a bit behind the wagon on this one - I want to start playing with more of the advanced technologies (until recently I have used OpenGL to nicely render my experiments with various graphics algorithms, such as the construction of my particle system... those sorts of things). So, it''s time to make a decision. Do I need to take the plunge and dump OpenGL for Direct3D simply because D3D is now superior?

Personally, I''ve done the opposite - I''d been using Direct3D since 1999, but have now (september) switched to OpenGL for various reasons. I don''t especially want to stay around for when Microsoft''s licensing for Windows becomes fascist, so I''ve almost completely migrated to Linux. I''m still developing for both platforms, but it does mean Direct3D isn''t a very useful choice.
Also, while Direct3D is fundamentally well-designed (more so than OpenGL if you''re talking about advanced features), the constant changes from version to version have started to annoy me, even though they''re only minor. In OpenGL you can simply add any new stuff that comes along to what you already have, for example by adding a renderpath in your engine. No existing code has to be updated.

quote:

I''ve told myself time and time again that OpenGL 2.0 (when/IF it ever gets here) is going to blow D3D out of the water once again. I think many of us tell ourselves that. But the question remains: what IS the status of OpenGL 2.0?

Well, what was supposed to be OpenGL 2.0 has now been released as 1.5 as far as I can tell, even though there''s still stuff missing, which will turn up over the next few months. In a way, I''m not too bothered about what they call it, if they got the job done and call it something else I''m happy with that. Right now I can''t think of anything that OpenGL doesn''t do that Direct3D does in terms of functionality. OK, so GLSL/GLSlang isn''t finalised yet, but it''s damn close and you can still use D3D HLSL to generate assembly shaders and use those in an OpenGL app if that''s what you need.

quote:
What is going to happen to OpenGL 2.0 given that Microsoft is never going to support it in Windows?

Microsoft doesn''t support OpenGL 1.2, but that doesn''t prevent driver manufacturers and developers from using it. OK, so it''s not exactly very nice, but you can use wrappers (see the FAQ of this forum) to do that for you. It''s not a big deal. If you want a real OpenGL implementation, use a different OS. Linux, *BSD, MacOS all can support 1.5 as far as I know. I''m using 1.3/1.4 under Linux myself.
Also, OpenGL is very much associated with the Open Source community, and they''re well known for coming up with solutions to problems that big corporations don''t want to. Read: someone may write a third-party, compatible opengl.dll which supports higher versions. If the ARB get involved with it, I doubt anyone would hold back on using it.

quote:
Also - since I''m really a noobler to the more advanced extensions, I''m baffled by what so many people continually tell me about them. Right now extensions from OpenGL all the way up to 1.3 I have been using manually. So uhm... I will continue to be able to do that for OpenGL 2.0, right? See I''m not clear on this. I would like to be - but I can''t find any information on it to save my life!

I doubt that OpenGL will lose its backwards-compatibility anytime soon, that would just go against its own principles. Even if it did, someone would no doubt write support for Windows.

quote:
Would someone in the know - throw me and nooblers like me a bone - Should I abandon all hope of cross platform engines and D3D-free simulations?

No, definitely not, for above reasons.
Besides, OpenGL is still used actively in game development. Most big engines are either OpenGL, or both Direct3D and OpenGL.

quote:
PS. Sorry if this should have gone in the Beginner''s form. It was so OpenGL specific that I figured maybe it should be here :/

I''d be more worried about getting the thread closed for danger of flamewar.

- JQ

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Thank you for your lengthy and reasonable reply.
I really am not asking for a flamewar. Last thing I want I simply fear that it maybe time to acknowledge one side or the other - that is, if I wish to be a successful graphics developer.

Please, no flames.
I am not trying to make any points, just asking questions because I''m frustrated, slightly clueless, and... I can''t be the only one.

Thank you for being considerate. :D

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quote:
Original post by Xori
I''ve told myself time and time again that OpenGL 2.0 (when/IF it ever gets here) is going to blow D3D out of the water once again. I think many of us tell ourselves that. But the question remains: what IS the status of OpenGL 2.0?

The ARB is taking their time with OpenGL 2.0. What new feature would it include that you really need over what an extension (possibly standardized in some 1.x release) could offer? OpenGL 2.0 is meant to be the "cleaning up" release, to unify the interfaces to some of the features (babbling: I''d love to see the VBO usage-model style attributes applied to things like textures); I''d rather they take their time on it.

quote:
Original post by Xori
What is going to happen to OpenGL 2.0 given that Microsoft is never going to support it in Windows?

Just access its features through extensions in Windows ; possibly write a wrapper to make it effortless, just like what one has always done to make up for Windows'' out-dated OpenGL implemenation. Certain video cards with certain drivers (can''t really give you specifics from memory; 3Dlabs and possibly certain ATI products, I think) already expose pre-standard implementations to certain OpenGL 2.0 features through extensions (Carmack claims to have implemented an experimental "OpenGL 2.0" path in his Doom 3 code using these extensions).

quote:
Original post by Xori
Also - since I''m really a noobler to the more advanced extensions, I''m baffled by what so many people continually tell me about them. Right now extensions from OpenGL all the way up to 1.3 I have been using manually. So uhm... I will continue to be able to do that for OpenGL 2.0, right?

Why wouldn''t you be able to? OpenGL 2.0 will likely "force" the support of certain extensions much like the 1.x releases have done and/or simply have the functionality of the extensions as part of the core standard (especially the latter if they change the interfaces any). Everything I seen has indicated that early OpenGL 2.0 standards will require backwards compatibility with OpenGL 1.x standards (and that wouldn''t be all that difficult to do, considering how little will change and that the old functionality will be able to simply wrap over the new).

In summary: keep using OpenGL 1.x if you want to, the moderately-distant release of OpenGL 2.0 is nothing to worry about.

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As a side note, no matter what API you use, it''s always good to keep up with how the other API develops, and how it goes about things, as it quite often makes understanding easier, and helps with design decisions in your own application.

- JQ

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      I've read that if i could render each grid relative to the camera i could get better precision on the surface, effectively
      getting rid of those rounding errors.
       
      My question is how can i achieve this relative to camera rendering in my scenario here?
      I know that i have to do most of the work on the CPU with double, and that's exactly what i'm doing.
      I only use double on the CPU side where i also do most of the matrix multiplications.
      As you can see from my vertex shader i only do the usual r_ModelViewProjection * (some vertex coords).
       
      Thank you for your suggestions!
       
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