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fir

OpenGL
isnt opengl to high or to low

16 posts in this topic

I dont know but when i compare opengl with some higher level 

functions opengl seem to be just to low level making me programming

boring lowlevel things -so i thing it is to low level api On the other side for

lov level maniacs this is probably to high level not giving control over each

possible lov level hardware possibilities... So for me it seems that opengl

is both to low level (taking one philosophy of what it should be) and to high

lewel taking the other philosophy. what are the opinions?

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It's not "too" high, nor "too" low. That can only be assessed on a case-by-case basis of application with specific details.

 

GL provides an essential+necessary functionality. "Higher level" projects are built on TOP of GL.

 

For example, if your goal is to make a game ... Then another project might be more suitable, such as Irrlicht, OGRE, etc.

 

But, GL provides a high level of flexibility and performance, without dictating how certain things should be handled. So if you want to do something a specific way without being forced in some direction by an existing codebase, then GL is applicable. As well as even when using something existing, you can still possibly modify/extend it with GL.

 

Also this might have to take into account your own personal level of ability or experience with development.

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I think there are possible two points of view

 

1) one that such thing like opengl should be compact

logical not tu much burden of internal details

 

2) that it should be as low level as possible (or

as low level as it counts, it means that taking it to 

lover level will not give programmers more usable

ways of doing things 

 

for sure opengl do not conforms to (1) and I cannot be sure but it probably do not conforms to (2) so i doubt if there is some rational 

ground for that it looks like it looks (for me i must admit opengl

looks ugly and strange) [though i must say i have only some partial

view on this and also readed some opinions, Im far of knowing it

good - so im curious what others can say as to that]

Edited by fir
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I actually tend to agree with the original suggestion. I feel like OpenGL falls into an awful pit where it is neither low level enough to provide sufficient control, nor high level enough to provide sufficient abstraction. It's just a headache for both. The correct thing would be for it to be more low level, of course. Whether they're making useful progress in that vein... I think the jury is still out.

Edited by Promit
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how low, how high is subjective to from where you looking at . From perspective of  game dev I would say its pretty low and that's why writing a solid abstract middleware(not be confused with extension) is must for any medium to high end production. I would like to hear about scenarios while you  felt lack of control due to over abstraction by opengl.

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OpenGL is higher level than modern incarnations of Direct3D.  OpenGL 1 was not designed for anything resembling modern hardware.  OpenGL 3 was designed around a number of assumptions about where hardware would go but which did not pan out.  OpenGL 4 has done its best to move GL back towards the reality of hardware but Khronos' refusal to break backwards compatibility or to continue using the deprecation model of GL 3.1 (it's sometimes called a "failure" even) leaves OpenGL with a lot of cruft that doesn't directly match real hardware.

 

Seems I'm not the only one who feels this way.  I'm still completely baffled as to why they are so stuck on backwards compatibility.

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desire) there would still need to be a lower-level layer under it.  Considering OpenGL to be too low-level doesn't mean that something is wrong with OpenGL, it means that something is wrong with the choice you've made and that you need to back off and rethink.

I am low level man too, but there seem maybe two kind of low level 

 

 

1) RAW low level when you just have strict acces to hardware

 

2) some managed lov level when you got a lot of complrx idioms of opaque functions to use to get low lewel things done

 

I am not sure (I do not know OGL too much yet) but it seem to me

that OGL maybe gone into second way, This opaque low level is not a thing that i would be crazy for, (thats probably why i must call it 'ugly and strange', though i like simple c flavor of it )

Edited by fir
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There is OpenGL and Direct3D so you dont have to program using the interfaces the GPU drivers would give you. It has to be higher-level than the API on a console cause it has to work for many different GPUs.

The API is the way it is, but normally you write wrappers around its objects ....so you wont see its arcane functions all the time.

 

Heres a good presentation, ...he talks a lot about why is openGL good/bad. (and rants a lot too).

https://www.youtube.com/watch?v=IXxc9yNBpuo

 

BTW if you want to see a change you are free to talk to the ARB memers and/or be there on the meetings.

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BTW if you want to see a change you are free to talk to the ARB memers and/or be there on the meetings.

 

...but don't imagine it will get you that change, because it won't.

 

OK, if you're a AAA studio you can push the hardware vendors for some new extensions and in a few years time they might be rolled into core.  Otherwise - well all anyone has to do is point out all of the online clamouring about the ancient binding model as evidence.

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Heres a good presentation, ...he talks a lot about why is openGL good/bad. (and rants a lot too).


Haha. I did rant a little more than I probably should have in that talk. smile.png
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Haha. I did rant a little more than I probably should have in that talk. smile.png

 

All the rant-points were legit.

(Thanks for those great talks BTW! ....I really enjoyed the one about game engines and the 8-hour game. I wish I saw that a few years ago:))

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desire) there would still need to be a lower-level layer under it.  Considering OpenGL to be too low-level doesn't mean that something is wrong with OpenGL, it means that something is wrong with the choice you've made and that you need to back off and rethink.

I am low level man too, but there seem maybe two kind of low level 

 

 

1) RAW low level when you just have strict acces to hardware

 

2) some managed lov level when you got a lot of complrx idioms of opaque functions to use to get low lewel things done

 

I am not sure (I do not know OGL too much yet) but it seem to me

that OGL maybe gone into second way, This opaque low level is not a thing that i would be crazy for, (thats probably why i must call it 'ugly and strange', though i like simple c flavor of it )

 

 

I would say there isn't just two levels, "high" and "low", there are many layers of abstraction, and if they are "high" or "low" depends on the context.

Edited by Olof Hedman
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