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OpenGL Is there a need for another modern OpenGL guide?

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Hi,

[font=verdana, arial, helvetica, sans-serif][size=2]I'm thinking of writing a modern OpenGL guide. I realize that more and more modern OpenGL guides are popping up, but I think there are still things that most (if not all) of them lack:[/font]
[font=verdana, arial, helvetica, sans-serif][size=2]
  • A site that can be corrected and updated by users, e.g. a wiki.
  • Information for setting up your context in every language and platform (C++, C#, WebGL, Android, ...).
  • Bare-bones interaction, not letting libraries do everything for you. At least not in the beginning.
  • Beats NeHe's tutorials in Google's search results (I've registered http://open.gl for this exact purpose).
  • Including everything in one place. The current situation makes modern OpenGL too hard to learn.
    I've come up with the following structure for the site I want to develop:

    http://codepad.org/4yH2kxLl




    I'd like to hear your input.

    [/font]

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This is your first post on these forums and we don't know your level of expertise on the subject. Can you provide some references ? How many years have you been professionally working with OpenGL ? Do you have a proven track record in this domain, did you publish any publications ? Were/are you involved with the ex-ARB, Khronos or one of their major contributors ? Are you working on the GL driver development team of a major GPU manufacturer or of an open source driver ? Were you directly involved in the development of an OpenGL based rendering backend for a major game, application or middleware ?

If the answer to all of these questions is no, then you shouldn't be writing "another modern OpenGL guide".

Sorry for being so blunt, and I applaud your motivation. But the answer to your title question is, no, we don't need another such guide. What we do need is a single, authoritative development and learning resource for OpenGL, published and maintained by an officially endorsed and highly qualified organization. We don't need another open wiki, we don't need another gazillion of tutorials, we don't need to "beat" NeHe. We need Khronos to finally get their stuff together and release an actual OpenGL SDK and updated human-friendly documentation (ie. not the extension doc text format). In other words, we need an MSDN equivalent for modern OpenGL.

So if you have some good ideas, then you should try to contribute to the more or less 'official' OpenGL wiki instead, helping to bring it out of its current desolate state.

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So if you have some good ideas, then you should try to contribute to the more or less 'official' OpenGL wiki instead, helping to bring it out of its current desolate state.


I am afraid I won't be able to, as I do not currently have a PhD in graphics programming. Nor do I meet any of your other royal standards.

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we need an MSDN equivalent for modern OpenGL.



No

Are you under a delusion that OpenGL is so complex that it requires professional experience to simply explain it to beginners? Adding more crap to the pill of crap won't help, and waiting for someone else to do it is lazy, what harm could come from making another website that would not anyways happen from bogging down a already unhelpful website?


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I am afraid I won't be able to, as I do not currently have a PhD in graphics programming. Nor do I meet any of your other royal standards.

No need to get defensive. You are planning to write what basically amounts to a significant amount of teaching material targeting beginners. Well written teaching material can be an excellent resource, while badly written (often due to lack of knowledge) is highly counterproductive. Unfortunately, most online tutorials fall into the later category. As such it is absolutely valid to ask about your own expertise on the subject. If someone offered to teach me how to fly an airplane, I would inquire about his own license first.


[quote name='Yann L' timestamp='1306025861' post='4814040'] we need an MSDN equivalent for modern OpenGL.

No
Are you under a delusion that OpenGL is so complex that it requires professional experience to simply explain it to beginners?
[/quote]
Yes, absolutely. Significant experience is a prerequisite for teaching any form of advanced concept to a beginner. No need for a PhD, but if you don't know the material inside-out, then you have no business teaching it.


Adding more crap to the pill of crap won't help, and waiting for someone else to do it is lazy, what harm could come from making another website that would not anyways happen from bogging down a already unhelpful website?
[/quote]
You mean like NeHe, for example ? Spreading incorrect information, even unintentionally, is worse than not spreading any information at all. I am not saying the OP is in this position, that's why I inquired about his experience with OpenGL.

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In other words, we need an MSDN equivalent for modern OpenGL.



There are few things I want to see happen as badly as that.

I know that Microsoft is out of the question, but at the very least Apple should step up to the plate. They've done a pretty good job at creating very MSDN-like knowledge base for IOS development, among other things. My respect for Apple would increase drastically if they helped propel OpenGL as Microsoft did with DirectX, and with a market share over $300B they should have the money to blow away on increasing the standards of all the technologies their own software and operating systems rely on!

/anxious-to-see-opengl-truly-mature


I don't know what Polkm's deal is but he has clearly never used MSDN, I use it on a daily basis just about and can say with utmost confidence that he has no idea what he's talking about. Some examples; I was recently working on a C++ application to visualize music, and in that process I wanted to try and visualize audio playing through the system's audio endpoint, to get around having to play a specific MP3 or write a plug-in for an existing media player. So what I did is research the Windows 7 audio platform and architecture on MSDN, found the API's on MSDN, and even some sample code on MSDN, as well as ridiculously clear and intuitive information on how it was all connected (hell, they even create logical diagrams for you). Within a couple hours I had it all done and my software was running as I wanted, much simpler than it was for XP.

http://gltiich.blogs...-windows-7.html

Not long after that I bought some MIDI instruments, again, Microsoft documented everything so well and so clearly, that I was up and going with my own MIDI software to do some stuff for fun in just a couple hours (piecing everything together at first can be a bit slow hehe).

http://gltiich.blogs...put-with-c.html

MSDN has STL C++ documentation, and even entire sections around clever/neat short-hand notations and tricks. Things I never found so well centralized or organized on C++ focused websites like cprogramming.com or cplusplus.com. After having been developing with C++ for years I came across those sections in MSDN and learned quite a few new things and even had better clarity on many features I didn't have before then.

Also all of their platforms are documented in detail and followed-up with technical and howto articles.

Learning OpenGL in contrast for me was a long and painful experience, specifications are not clear or intuitive. I spent years trial-and-error developing a lot of it and piecing together a lot of separate specification documents to build the 'whole picture' conceptually. I don't care who you are or how smart you think you are - that is not a good method to learn something, especially if you want broader acceptance out of the professional gaming industry.

An MSDN equivalent for OpenGL is exactly what OpenGL needs in order to have a foundation to back its marketing. OpenGL as a whole needs to grow up, not just it's API, but everything around it including a support base for future/new programmers.

Finally, clearly, Microsoft has a conflict of interest in supporting OpenGL, even though they do to a limited extent (documentation wise). But a major player that is as well as financed like Apple, that could really make this all happen, it must! >:]

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Yes, absolutely. Significant experience is a prerequisite for teaching any form of advanced concept to a beginner. No need for a PhD, but if you don't know the material inside-out, then you have no business teaching it.



I agree, but that is not what you were saying before. You were asking for professional experience, significant and professional are different. I am not interested in a deep argument over linguistics though. I say no to MSDN because it has only minimal documentation, and rarely covers relevant application. When I was starting out, MSDN might as well have been written in Latin. Beginners often have to resort to tutorial websites because the documentation website was written, unintentionally, for people who already know how it works.

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why gamedev members like to derail threads to their own liking like this?


This guy has asked a clear question: "IS THERE A NEED FOR AN OGL GUIDE?"

I mean really its very clear.

And Im not talking bout this thread as a single example, many many times (including threads made by myself) this kind of behavior appears


And yeah, personally, Yes I think there is a need for an OGL guide that has no assumptions whatsoever . (well at least I need one xD)

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I thought Yann L's answer was pretty clear as well. If you don't have experience implementing most of the useful features of modern OpenGL in a professional or academic context as well as a thorough understanding of the graphics pipeline as implemented in current hardware, your efforts are likely to be only marginally better than what's already out there. If this is the case, the project is unlikely to become a "definitive guide", and your efforts are better served contributing to the existing wiki.

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I'm thinking of writing a modern OpenGL guide. I realize that more and more modern OpenGL guides are popping up, but I think there are still things that most (if not all) of them lack:
  • A site that can be corrected and updated by users, e.g. a wiki.
  • Information for setting up your context in every language and platform (C++, C#, WebGL, Android, ...).
  • Bare-bones interaction, not letting libraries do everything for you. At least not in the beginning.
  • Beats NeHe's tutorials in Google's search results (I've registered http://open.gl for this exact purpose).
  • Including everything in one place. The current situation makes modern OpenGL too hard to learnI think that's great that you collected what other sites lack, and hats off to your enthusiasm. The question is can you make a tutorial site that can match the other sites, and correct these things you listed?
    [/quote]

    Personally I wouldn't care how deep you understand OpenGL, because as far as you don't write bulls..., and as far as it works I think anyone can write one.
    I think noone can understand OpenGL as deeply as the people who created it, or belong to any of the categories Yann L listed, and for an "everyday guy" it is impossible to become one of them.
    And I don't think those guys have time to write such sites.

    I think these sites also lack the ability to present the concepts of developing an OpenGL based GAME ENGINE. I mean I don't really like to write samples all the time. So in that sense your site could be far better than the present ones.

    So I do think there's a need, but only if you can meet those requirements you listed (and match the other sites).

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      The matrix that result from the multiplication of R and T (in that particular order) is send to my vertex shader as `r_Grid'.
      // spherify vec3 V = normalize((r_Grid * vec4(r_Vertex, 1.0)).xyz); gl_Position = r_ModelViewProjection * vec4(V, 1.0); The `r_ModelViewProjection' matrix is generated on the CPU in this manner.
      // No the most efficient way, but it works. glm::dmat4 Camera::getMatrix() { // Create the view matrix // Roll, Yaw and Pitch are all quaternions. glm::dmat4 View = glm::toMat4(Roll) * glm::toMat4(Pitch) * glm::toMat4(Yaw); // The model matrix is generated by translating in the oposite direction of the camera. glm::dmat4 Model = glm::translate(glm::dmat4(1.0), -Position); // Projection = glm::perspective(fovY, aspect, zNear, zFar); // zNear = 0.1, zFar = 1.0995116e12 return Projection * View * Model; } I managed to get rid of z-fighting by using a technique called Logarithmic Depth Buffer described in this article; it works amazingly well, no z-fighting at all, at least not visible.
      Each frame i'm rendering each node by sending the generated matrices this way.
      // set the r_ModelViewProjection uniform // Sneak in the mRadiusMatrix which is a matrix that contains the radius of my planet. Shader::setUniform(0, Camera::getInstance()->getMatrix() * mRadiusMatrix); // set the r_Grid matrix uniform i created earlier. Shader::setUniform(1, r_Grid); grid->render(); My planet's radius is around 6400000.0 units, absurdly large, but that's what i really want to achieve;
      Everything works well, the node's split and merge as you'd expect, however whenever i get close to the surface
      of the planet the rounding errors start to kick in giving me that lovely stairs effect.
      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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