Re: NSOpenGLView

[Philippe C.D. Robert]

On Nov 8, 2006, at 2:34 PM, Enrico Sersale wrote:

> On 2006-11-08 15:26:35 +0200 Renaud Molla <renaud.molla@wanadoo.fr>  
> wrote:
>
> > Enrico:
> > What do you mean by [[self openGLContext] flushBuffer] does the  
> > trick?
>
> I mean that an implementation of -drawRect: like this:
>
> - (void)drawRect:(NSRect)rect
> {
>   glClearColor(0, 0, 0, 0);
>   glClear(GL_COLOR_BUFFER_BIT);
>   glColor3f(1.0f, 0.85f, 0.35f);
>   glBegin(GL_TRIANGLES);
>   glVertex3f(0.0,  0.6, 0.0);
>   glVertex3f(-0.2, -0.3, 0.0);
>   glVertex3f(0.2, -0.3 ,0.0);
>   glEnd();
>   glFlush();
>
>   /* add this line */
>   [[self openGLContext] flushBuffer];
> }
>
> will work without the need of a timer.

If this is a double-buffered context then -flushBuffer issues a call  
to glFlush() (at least it should...), and thus glFlush() should not  
be called at all. if it is a single-buffered context then - 
flushBuffer is a nop and glFlush() has to be called! At least if the  
GNUstep implementations behaves like Cocoa ;-)

HTH,

-Phil