Hi!

This is what AMD_gpu_association states:

"To render using an associated context, it must be made the current 
  context for a thread: 
  BOOL  wglMakeAssociatedContextCurrentAMD(HGLRC hglrc);
  <hglrc> is a context handle created by calling 
   wglCreateAssociatedContextAMD."

There's no HDC you could pass into this function.
>From the wording of "must" I conclude that this is the _only_ permitted way
to make such a context current. Although, it is not explicitly stated that
wglMakeCurrent(hdc, my_associated_context) is forbidden :-(

Later on the specs say:

" When an assoicated context is bound, the default state for an associated 
  context is invalid for rendering. Because there is no attached window, 
  there is no default framebuffer surface to render to. An app created 
  framebuffer object must be bound for rendering to be valid."

This seemed to strengthen my assumption that it is not possible to render
into a window when using an associated context.

So, how would you make your rendering visible, if you can only render
offscreen? That's why I claimed, you'd need to do an explicit blit into a
window. Of course, if you don't need the rendering to be visible, no blit is
needed ;-)


Best regards,

Mathias


> -----Original Message-----
> From: [email protected] [mailto:eq-dev-
> [email protected]] On Behalf Of Stefan Eilemann
> Sent: Monday, March 15, 2010 1:59 PM
> To: Equalizer Developer List
> Subject: Re: [eq-dev] Dependancies for building with VS2008?
> 
> 
> On 11. Mar 2010, at 16:29, Mathias Heyer wrote:
> 
> > AMD_gpu_association can ONLY render into offscreen FBOs, not into
> windows.
> > You are supposed to blit the result of a rendering (using an 'associated
> > context') into a window (bound to a second, unassociated context) by
> > wglBlitContextFramebufferAMD().
> 
> From what I've been told by ATI, the blit is not necessarily needed. If
> you create a window on a single GPU, and don't move it, you'll have
> optimal performance.
> 
> Of course, for a multi-GPU workstation you probably want n offscreen
> buffers and one (movable) window in which you blit the result into.
> 
> 
> HTH,
> 
> Stefan.
> _______________________________________________
> eq-dev mailing list
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