Ogre : many OpenGL features are lost

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n9ine
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Ogre : many OpenGL features are lost

Post by n9ine »

Hi all;

The features that ogre is able to do are the ones that are common to OpenGL and Directx. But Since the two
APIs do not have the same politics. This leads to loosing many feature (espacially from OpenGL).
What I hope, it that Ogre do the Union of features not the Intersection. And any feature will be acvtivated since one or another render system was choosing.
:?

ps: "This is just a point of view it is not a critic".
Last edited by n9ine on Fri Aug 13, 2010 1:04 pm, edited 2 times in total.
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Re: Ogre Diplomacy: many OpenGL features are lost

Post by CABAListic »

This is way too vague. You really need to propose particular features, not such a general statement, if you want anything done ;)
You will probably have to make a strong case why you really absolutely need that feature, though, because the choice of rendersystems is meant to be transparent, and as such non-matching features are against Ogre's design principles.
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Re: Ogre Diplomacy: many OpenGL features are lost

Post by n9ine »

Yah I understand that, I know that such thing is out of Ogre Design.
For mu case, I hope that LINE drawing parameters can be added (line width, striple,...).
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Re: Ogre Diplomacy: many OpenGL features are lost

Post by spookyboo »

Ogre does not prevent you from doing raw OpenGL. You only have to do it yourself, outide Ogre
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Re: Ogre Diplomacy: many OpenGL features are lost

Post by jacmoe »

/* Less noise. More signal. */
Ogitor Scenebuilder - powered by Ogre, presented by Qt, fueled by Passion.
OgreAddons - the Ogre code suppository.
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Re: Ogre : many OpenGL features are lost

Post by n9ine »

Nice, But I think It can be made in a better way than with FrameListners.
:idea:
Last edited by n9ine on Fri Aug 13, 2010 1:05 pm, edited 1 time in total.
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Re: Ogre Diplomacy: many OpenGL features are lost

Post by jacmoe »

It's not using framelisteners...
/* Less noise. More signal. */
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Re: Ogre : many OpenGL features are lost

Post by n9ine »

Yah Yah,
jacmoe wrote:It's not using framelisteners...
I mean RenderQueueListners...
Last edited by n9ine on Fri Aug 13, 2010 1:06 pm, edited 1 time in total.
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Re: Ogre Diplomacy: many OpenGL features are lost

Post by jacmoe »

Instead of whining you should be glad that Ogre is so flexible! :)

I would not like Ogre to have an inconsistent API because the render systems are carrying different and/or conflicting features.

OpenGL Line width is a hack, and can be easily implemented using shaders.
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Re: Ogre : many OpenGL features are lost

Post by n9ine »

thanks, I know that Ogre is so big, I am not criticizing Ogre ( :wink: ).
This is just a point of view, for those how may be interested in.
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Re: Ogre : many OpenGL features are lost

Post by dark_sylinc »

IIRC, line width is deprecated in OpenGL.

This is the problem with OpenGL, too many features being supported with little testing or documentation, and they're so many sometimes the documentation starts getting obscure (i.e. driver bugs, anyone?)

Also another problem is mantaining extensions. Often you have feature XYZ, which is implemented by NVIDIA, it gets called "NV_XYZ", then by ATI, so you get "ATI_XYZ", and then it gets into core: "GL_XYZ"
Not to mention if this extension is too old, it may happen a recent driver removed support for it's particular extension because nobody actually used (i.e.) ATI_XYZ.

So you end up implementing the same thing 3 times, and not even at all at once. You have to wait. Sometimes even years.
If you have the dedication to implement everything around 3 times, remove deprecated OGL functionality while still ensuring Ogre supports it, then you're welcome to try it.
Also don't forget you will need an easy, clear way to tell developers they can't use feature "ABC" if they're using Direct3D plugins, so they take it into account and doesn't unexpectedly crash.
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