Heh, well.. I can get it to hover around 10ms (even drop to 7 or 8
sometimes) with double-buffering turned off and using raw GDI calls, but
with double-buffering it's still noticeably sluggish.
So it's a trade-off between flickering like hell or slow repaint.
"Alien" <alien@sympatico.ca> wrote in message
news:VTqSa.8043$2h1.3461@news02.bloor.is.net.cable .rogers.com...[color=blue]
> Thanks for your help
>
> I am double-buffering, though not using the SetStyle method. Painting only
> the regions that have changed can get a bit tricky in a textbox, but I
> should probably give it a try. However, it does not solve my main[/color]
problem..[color=blue]
> When the control is scrolled, everything changes, so I'll have to repaint
> the entire control anyway.
>
> I'm now trying to use GDI API functions instead of the wrappers (GDI+)[/color]
..NET[color=blue]
> provides, and in my experimenting they are a bit faster (repaint time down
> to 40-50ms, and if I turn off double-buffering, 10-20ms).
>
> "Jon Davis" <jon@REMOVE.ME.PLEASE.jondavis.net> wrote in message
> news:elVQf9nTDHA.2324@TK2MSFTNGP12.phx.gbl...[color=green]
> > I've done only a small amount of System.Drawing work, but I think I can
> > still make a suggestion: Don't paint anything that hasn't changed. When[/color][/color]
a[color=blue][color=green]
> > form is updated for painting, find the region that is being repainted,[/color]
> then[color=green]
> > repaint only that region. A little 32x32 square or even a skinny 2x500
> > rectangle will paint much faster than a massive 640x480 area.
> >
> > Also, be sure you're double-buffering, to eliminate the flicker ...
> >
> > public MyControl()
> > {
> >
> > // Activates double buffering
> > SetStyle(ControlStyles.UserPaint, true);
> > SetStyle(ControlStyles.AllPaintingInWmPaint, true);
> > SetStyle(ControlStyles.DoubleBuffer, true);
> > //
> > // Required for Windows Form Designer support
> > //
> > InitializeComponent();
> >
> > }
> >
> >
> > HTH,
> > Jon
> >
> >
> > "Alien" <alien@sympatico.ca> wrote in message
> > news:GkkSa.6265$PJF1.4991@news01.bloor.is.net.cabl e.rogers.com...[color=darkred]
> > > I have a hex editor-type class that extends UserControl and paints its[/color]
> > data[color=darkred]
> > > to a PictureBox. Basically the problem is that repainting it takes[/color][/color]
> usually[color=green][color=darkred]
> > > between 60 and 80ms, which may seem pretty fast but is not good enough[/color]
> > when[color=darkred]
> > > you have to repaint very frequently. For example, when you scroll the
> > > control or select blocks of text quickly.
> > >
> > > I have it paint its graphics to an offscreen Graphics instance, which[/color][/color][/color]
I[color=blue][color=green]
> > then[color=darkred]
> > > transfer to the PictureBox using g.DrawImage(Image m, int x, int y)...
> > > Making it paint directly onto the PictureBox is (understandably) even
> > > slower.
> > >
> > > So, is there anything I can do to improve the situation or am I stuck?[/color][/color]
> I'm[color=green][color=darkred]
> > > on a 1.4ghz Athlon by the way.
> > >
> > >
> > > Thanks
> > >
> > >
> > >[/color]
> >
> >[/color]
>
>[/color]
