<P> But is that true even if you are not doing it for messaging purposes, <BR> but instead having the timer call the callback?</P>
<P>You need a message pump in order to dispatch WM_TIMER message.</P>
<P> Also, the question would be what is VTK doing in it's event loop<BR> regarding handling events to the window? Then I could get the Window<BR> handle and have it receive the messages</P>
<P>SetTimer( NULL, ... )<BR>Your timer is not attached to a window.<BR>I don't think VTK does something, except to call DispatchMessage.<BR>My warning was if you use SetTimer without any Window => without any message pump.<BR></P><BR><BR>Aurélien REGAT-BARREL<p>Yahoo! Mail - Votre e-mail personnel et gratuit qui vous suit partout !<br> Créez votre adresse sur http://mail.yahoo.fr