Re: slow OpenGl or RunLoop misunderstanding ?

[xavier . glattard]

Selon Richard Frith-Macdonald <richard@tiptree.demon.co.uk>:

>
> On 15 Jan 2007, at 20:25, xavier.glattard@free.fr wrote:
>
> >
> >   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
> >   [_scene glDrawFrame];
> >
> >   [[self openGLContext] flushBuffer];
> > }
> >
> > I've tried to comment out the 3 last lines :
> > - when all 3 lines disabled I get 3040 FPS ! (yes, 3 thousands)
> > - when i left any of the lines I get 380-480 FPS... (4 hundreds)
> >
> > It looks like my opengl is so slow... (not accelerated ? why ?!)
>
> I agree that it looks like there may be a hardware acceleration
> problem.  Perhaps you could try hacking initWithFormat:sharedContext:
> to see if changing any of the context initialisation will effect
> things (when googling this I saw a comment somewhere about direct
> rendering disabling acceleration on some system).
>
> > and RunLoop has no responsability (no "wait state").
> >
> > Xavier
> >

Finally you were right in your first answer : RunLoop delays
the  'needDisplay event' (every 1/500 sec ?) :
when i change my loop to a timed one (NSTimer...) _and_ use
[-lockFocusInRect:}/[-drawRect:]/[-unlockFocus] instead of
[-setNeedsDisplay:] i get more than 2000 FPS :-)

As I think the timer way is nothing but a workaround
I'm going to look for a way to change that... :o)

Xavier