some startup questions about Jogl

[SDV]

i got a first impression how to work witch jogl through How to: Getting started with JOGL

but there are some unanswered questions like what is different in jogl than in ogl
are there ways to create non 2^n sized textures (pbuffers?) or whatever so that i can make a buffer wich i dont have to resize when drawing it onto the screen
more or less the same with pictures… how to load and process non 2^n x 2^m sized pictures… without resizising it (if u dont want to) or storing a (2^n)+1 picture into a 2^(n+1) texture

how to masure the fps (time to create one frame bot working parralel in 2 threads [awt and game logic]) in jogl… where to draw how to syncronise my main thread with the drawing of my oglcanvas in the awt thread (as an Example: so that i wont let the game logic calculate 50 frames while only drawing 10)

only to mention the important ones

well im just asking if there are differences (maybe some neat wrappers) in jogl than in ogl itself… and if yes could u give me some references (tutorials) or whatever to read…
well if not ill see if i can find the std ogl solutions while reading all the ogl stuff (redbook and whatever)

well uhm… have to start reading

[tom]

There are some extensions to opengl that allows you to use non pow 2 textures. But if you want others to run your game it is wise to stick to pow 2 for now. As not all card/driver combos has those extensions yet.

You can only call OpenGL functions from one thread. I don’t use JOGL so I’m not completely sure how things stick together. There is probably an easier way than using the Animator and GLEventListener.

[SDV]

well yeah but one problem i will shurely get is if i draw in a texture (a quadrat) and draw this texture onto the screen it wont be a quadrat anymore it would be a rect…
but thats a general ogl problem i think so there should be an answer out there… somewere

[dvm]

Well, if I’ve understood your question, apart from the windowing stuff that each platform handles a bit differently (Java, Win32, X) there isn’t much difference. You should pay attention to the fact that you must be in the correct thread to run gl code. I mean, using C I used to put my mouse handling routines (that used gl functions) in the mouse callback. That’s not possible with JOGL so I just raise a flag and handle them inside display, before anything else.
Last thing, I just find a nuissance that we have to double the gl. Can’t they remove it from the method calls? So we write:
gl.Enable(GL.DEPTH_TEST);
instead of:
gl.glEnable(GL.GL_DEPTH_TEST);

[cylab]

@SDV
just use correct texture coordinates and viewport ratio while drawing your textures to the screen. http://nehe.gamedev.net/ is a great resource for that kind of stuff.

Basically you can store a 1024x768 image in a 1024x1024 texture, ignoring the lower 200+ lines. This would waste some texture memory, but if this is a problem depends on your application.

If you plan to use textures for model texturing you will do a lot of image-customizing anyway (like slicing your texture to save context-switches), so it will be no extra effort to store the textures in pow2 right away.

@dvm
use static imports and don’t call the instance gl.

current.glEnable(DEPTH_TEST)

looks much better

[nnevatie]

SDV, take a look at a recent discussion about non-pow-2 textures:

http://www.java-gaming.org/cgi-bin/JGNetForums/YaBB.cgi?board=jogl;action=display;num=1110639195