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mohitkhera

OpenGL help plzz

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mohitkhera    122
hi guyz i am a complete beginer to opengl.... i am trying to make a porject in it...biut facing lot pf prblms.... i am nt able to laod more than 1 model i am totaly confused with these translation matrixes n all i tried to use glpush matirix and popmatrix...bt no use can u guyz tell me how i should load anther model....

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Gage64    1235
You'll need to provide a lot more information than that (including source code) if you expect to get any help.

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jpetrie    13137
You should check out the OpenGL Red Book, which is free online at the OpenGL website. It explains some of the basics of the graphics pipeline that will help you understand those 'confusing' translation matrices and whatnot. It is critical that you possess the requisite fundamental knowledge before you go on to more complex 3D stuff, or you will only get yourself spun around and confused.

If you'd rather buy Real Books, I recommend a few good ones on the subject.

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bjarnia    219
If you don't understand anything about OpenGL the last thing you should be do is loading models.
Start at the beginning, don't dive into the hard stuff without knowing the basics.

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jpetrie    13137
Then you better start reading up on the material, hm?

You're probably translating the model off the screen. Translate by less.

It's flawed thinking to think you can skip the fundamentals because you have to finish your project in a week. If you take some time to learn them, you'll probably be able to produce something and just barely scrape by.

If you don't, you'll produce something terribly awkward and clumsy, and probably won't finish on time.

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mohitkhera    122
thanxz guyz for help...i am reading this chapter-viewing transformations frm
red book..hopefully it would clear my doubts...otherwise i would put my query here
and hey ya can anyone provide me a gud link of source codes apart frm nehe?

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aevanthony    100
http://en.wikipedia.org/wiki/OpenGL is a good start... there's some very basic examples to get you going along with an overview of the entire mess you're *trying to dive in to.


http://www.videotutorialsrock.com/

Wow! I just came across this, I haven't really looked at it so i can't speak for how good it actually is... but... you might find these tutorials intuitive since they're streaming video. I guess that'll make it easier to get in to at least...


Good luck.

[Edited by - aevanthony on April 23, 2008 2:52:44 PM]

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jpetrie    13137
Quote:

Lol yes, the Redbook, good starting point. Of course, there are also some... more suitable resources I'm sure?

Care to explain this? What exactly is unsuitable about the Red Book from the point of view of somebody needing to learn the fundamental concepts behind 3D graphics and OpenGL?

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aevanthony    100
I didn't mean it exactly like that.

I don't disagree about the recommendation, I just don't think that (from the sound of this person) it'd be likely he'd go through a 'giant book on opengl' (regardless of how you might see it.) I just happen to notice most people end up at random tutorials sites to learn things despite book recommendations. So it'd probably do better for him to give some other references other than a 'big book to read' which a lot of people dread. (sigh... then there's the day when you have to tear through the specifications.)

Sorry, I guess I gave the wrong impression.

Besides, seems a lot learn well they have their hands on code and such, not having to figure out how to piece it all together from a very long source. Even if it is the best* way technically, some people also give up too that way.


A lot of the 'Lol' came from the image in my mind, I mean, it just seemed very "i need teh helpz" then you're all "*slams the book on table*". I mean maybe it's not that way at all I just... ok I guess maybe I shouldn't be allowed to post on the internet.:):)

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jpetrie    13137
Yes, well. Source code isn't the best learning resource. Nor, come to think of it, are tutorials.

I, at least, am here to help people learn. Not to help people skate through their assignments by the skin of their teeth. You help people by telling them the right thing -- sometimes the right thing isn't the easy thing, or the thing they want to hear. Nonetheless, it is the right thing. Screwing around copying and pasting code from tutorials and reading the half-baked, oft-incorrect explanations from places like NeHe don't always (in fact, rarely) teach the appropriate fundamentals the appropriate way.

Sure, they get results. Lots of people conflate "results" with "comprehension." But this is not the case. I care about comprehension, because it will carry you further.

Besides, my firm belief is that if you can't be bothered to explore the background material at least a little, you have no business doing whatever it is you're trying to do. There's a reason the material is considered "fundamental."

Walk before you run.

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aevanthony    100
Your philosophy rings true and I agree, but I don't mind giving just what's desired if it might mean it'll provoke more curiosity.

(And I know I'm just keeping this conversation going but I'm enjoying it a little.)

Fundamental truths might be that but people certainly aren't inherently logical. Maybe you have to arouse curiosity with a little ease for a few to get them moving along. I just think it's most helpful to cater to everyone, even if it's initially not the best way, it might inspire someone to follow a truer path once they see something they like.

Mmmm... in my eyes, I see a clear difference between technical correctness and what it is to motivate someone to be technically correct. A lot of people won't do something if they don't think they need to. You have to convince them, it's a common trait in people.

I've learned a lot from mistakes, in various aspects, not just what seems obvious. At least when your feet are wet you've begun.

I don't support the notion that what comes from various internet references are absolute, or even suffice in a lot of cases. I've already resorted to the specification various times in learning GLSL. It's been made easier for me by using tutorials like lighthouse first though, only at first.

So while your philosophy is great, and every professional should abide to it, it's not always practical. And just because you start easy, doesn't mean you'd follow it through to the end that way.

:):):)

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