# OpenGL Any good Open source GL 3.x engines for reference?

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I'm trying to put together a little framework based on a strictly OpenGL 3.x context and I'm having a bit of trouble structuring some of my information and would like to take a look at how others may have solved the problem. I've looked/learned a lot from Ogre, Horde3D and the HP1Engine that FrictionalGames released last year, but so far either A) the engines don't utilize the aspects of OpenGL 3.x that I need help with or B) they do things I can't fully understand or follow. So I'm wondering if there's any other good modern engines that I can take a look at that I've missed so far. I'm currently working on the structure of my Shader system and VBO/VAO management and have found VAO implementations in the above engines to be seemingly nonexistent. Also defining a flexible vertex format and shader uniforms standards are hard to find or confusing in some of them as well.

The name "PolyCode" seems to be all the buzz lately and I've looked at that as well, the library/engine looks great and I've learned quite a deal from that as well, but it seems to use a hybrid of deprecated and non-deprecated OpenGL throughout which is something I'd like to avoid. Also as with the engines and libraries I mentioned above PolyCode does not appear to have VAO support yet.

So how about it? Any blatant resources I've missed for learning this stuff? I've got a copy of the OpenGL Superbible 5 as well which has served me well and taught me the fundamentals of HOW this stuff works, I'd just like to see more how existing systems do certain things but haven't had a whole lot of luck finding those who have adopted the latest GL tech.

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I don't really know of any popular OpenGL 3.x engines (well, I haven't tried looking for any), but if you want to have a look at my game library, here's a link: [url="https://github.com/supermaximo93/SuperMaximo_GameLibrary"]https://github.com/s...imo_GameLibrary[/url]. I'm not saying it's the best example of what to do though, it's just my take on OpenGL [img]http://public.gamedev.net/public/style_emoticons/default/smile.gif[/img] It doesn't use any deprecated functionality (I think [img]http://public.gamedev.net/public/style_emoticons/default/rolleyes.gif[/img]), and also uses VAOs. I haven't done any documentation for it though, although I will do soon. The OpenGL stuff is in the src > source/headers > Display.h/.cpp and the Font, Model, Sprite, Shader and Texture class files.

For some proof that the code actually does work [img]http://public.gamedev.net/public/style_emoticons/default/laugh.gif[/img] (although albeit an older version written in Pascal): [url="http://www.pascalgamedevelopment.com/showthread.php?9927-PGDmC-Mr-Snugglekins-and-the-Giant-Sack-of-Catnip"]http://www.pascalgamedevelopment.com/showthread.php?9927-PGDmC-Mr-Snugglekins-and-the-Giant-Sack-of-Catnip[/url]

I hope this helps [img]http://public.gamedev.net/public/style_emoticons/default/smile.gif[/img]

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a, BlendElf (If you can get the source of this out of SWIG then pls let me know.)<br />b, PixelLight<br />c, Psyche<br /><br />these are the first that came to my mind... they might not be pure OpenGL 3.x engines, or they may be 2.x but they're still a nice and modern example of what an engine should look like. To add you can learn a lot from them.

Sticking to OpenGL core context means not using deprecated functions. Besides FreeGLUT (and maybe GLFW) there are no libraries in which you can specify that you want pure OpenGL 3.x or 4.x functions, and the deprecated shouldn't event be present. In SFML though the author wrote on his forum that soon this feature will be available in SFML. It's really annoying when the source still compiles if you use deprecated stuff...

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[quote name='SuperMaximo93' timestamp='1312971183' post='4847104']
I don't really know of any popular OpenGL 3.x engines (well, I haven't tried looking for any), but if you want to have a look at my game library, here's a link: [url="https://github.com/supermaximo93/SuperMaximo_GameLibrary"]https://github.com/s...imo_GameLibrary[/url]. I'm not saying it's the best example of what to do though, it's just my take on OpenGL [img]http://public.gamedev.net/public/style_emoticons/default/smile.gif[/img] It doesn't use any deprecated functionality (I think [img]http://public.gamedev.net/public/style_emoticons/default/rolleyes.gif[/img]), and also uses VAOs. I haven't done any documentation for it though, although I will do soon. The OpenGL stuff is in the src > source/headers > Display.h/.cpp and the Font, Model, Sprite, Shader and Texture class files.

For some proof that the code actually does work [img]http://public.gamedev.net/public/style_emoticons/default/laugh.gif[/img] (although albeit an older version written in Pascal): [url="http://www.pascalgamedevelopment.com/showthread.php?9927-PGDmC-Mr-Snugglekins-and-the-Giant-Sack-of-Catnip"]http://www.pascalgam...-Sack-of-Catnip[/url]

I hope this helps [img]http://public.gamedev.net/public/style_emoticons/default/smile.gif[/img]
[/quote]

It does! I'm more looking for examples on how to Object-Orient stuff like VAOs (or if I even should) since they seem to hold so little information outside of native OpenGL state. Your model class doesn't appear to deal with that and instead opts for just having the classes that need a VAO to hold them internally in their pure form. This is still an option and seeing someone else doing it that way helps sway my final decision in just the way I was hoping it would. Also your straight-forward handling of Vertex Attributes and Uniforms is more or less exactly what I needed to see in order to get my brain out of it's endless loop of trying to abstract everything away to the infinitely generic level that gets me nowhere ;).

I'm still open to suggestions on engines that I can learn from. Yourse3!f I'll be taking a look at the ones you mentioned. I've never heard of BlendElf or Psyche but I HAVE heard of PixelLight and completely forgot about it until this moment! So thank you for that. Perhaps I'll find what I've been searching for in one of those.

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