pthread and opengl

[Leon]

Hey, i am trying to develop a game, and I am using OpenGL and pthread.
(on Ubuntu, so i also use the X library.) Now i have a problem. I have
initialized OpenGL in the main thread, and i want to repaint 30 times
every second (the usual framerate). Now i programmed a timer, which was
able to wait for 30/1000 seconds. That happens in another thread, and
after the delay (nanosleep, from the time.h header), it calls the paint()
function. And it returned a error message. I found out that it was
because OpenGL can't be painted from a different thread than the
initialising thread. Can anyone help me what to do to fix this? I can't
let the initialising thread delay and repaint, because it has to wait for
X inputs.

(main_thread)
|
\ /

(initialize OpenGL)
|
\ /

(start painting timer)
| \
\ / \
(wait for X events, XNextEvent()) |
\ /
(wait 30/1000 second, and then
call the repaint function)
Can anyone help me please?

grz, Leon

[dave_mikesell]

On Feb 10, 10:37 am, Leon
<[e-mail] e:

Hey, i am trying to develop a game, and I am using OpenGL and pthread.

You're better off asking in comp.graphics.api.opengl - this group only
deals with standard C++.

Keep in mind, though, that OpenGL is a big state machine and it's not
thread safe, so you have to manage thread access to the OpenGL
context.

[Leon]

On Sun, 10 Feb 2008 07:46:12 -0800, dave_mikesell wrote:

On Feb 10, 10:37 am, Leon
<[e-mail] e:

>Hey, i am trying to develop a game, and I am using OpenGL and pthread.

You're better off asking in comp.graphics.api.opengl - this group only
deals with standard C++.

Keep in mind, though, that OpenGL is a big state machine and it's not
thread safe, so you have to manage thread access to the OpenGL context.

Okay, thank you

[Rolf Magnus]

Leon wrote:

Hey, i am trying to develop a game, and I am using OpenGL and pthread.

Both OpenGL and pthreads are off-topic here. A better newsgroup for your
question is comp.graphics.api.opengl.

I found out that it was because OpenGL can't be painted from a different
thread than the initialising thread. Can anyone help me what to do to fix
this?

Most OpenGL implementations aren't thread-safe. You must do all the OpenGL
calls in one thread.