Re: Posting 60 messages per second to CView locks up UI (animation continues...)

From:

"Tom Serface" <tom@camaswood.com>

Newsgroups:

microsoft.public.vc.mfc

Date:

Wed, 10 Mar 2010 09:32:48 -0800

Message-ID:

<#CPj0eHwKHA.5812@TK2MSFTNGP02.phx.gbl>

I would be really surprised if this were MFC's fault. Have you tried
throttling the messages, like only sending on every 5 or something like
that?

Tom

"dan" <dan@nospam.com> wrote in message
news:OQxdxFHwKHA.5940@TK2MSFTNGP02.phx.gbl...

Hi,

As recommended by Jerry and Scott in this newsgroups, I experimented with
CreateTimerQueueTimer and PostMessage(WM_APP_...) to drive animations in a
CView derived window. I have 2 types of animations: GDI based and
Direct3D based. I noticed that Direct3D based animations were really
smooth when I ran them at a frequency which was close to the adapter's
refresh rate: 60hz. I was quite pleased to see the smoothness of the
animations and a very low CPU usage (alternating between 3-4%).

Unfortunately the app's UI (e.g. closing/sizing/moving the frame, menus,
etc.) became non-responsive. Other applications behaved normally so it
wasn't a system wide UI lockup.

It is a bit puzzling to me that at such a low CPU usage the UI becomes
unresponsive. Also, I can run animations at ~57 frames per second (which
I get when the timer delay is set to 17ms) and lower with no problem - the
UI responds as expected. Unfortunately animations are not that smooth as
at 60 frames per second (timer delay 16ms).

Does this sound like an MFC issue? Is this because the idle processing is
not taking place? Any workarounds? Would a non-mfc app behave better?

Thanks,
Dan