Vista - How to get the visual's snapshot in wpf? Do not use RenderTargetBitmap

I can use RenderTargetBitmap to get the visual's snapshot, but
RenderTargetBitmap use software render only. So it is very slow. When I
get a snapshot of a complicate visual element, it may cost 0.7s. Does
anyone has the faster way to do this?

If you want the contents of the Visual to be a bitmap you can manipulate, it
will have to be in SW eventually (since you aren't allowed to manipulate
video memory), and RenderTargetBitmap is the way to go. If your scenario
doesn't involve manipulating/saving the bits, it's possible there are other
solutions using VisualBrush - can you describe what you're doing with the
output of the RenderTargetBitmap?

-Adam Smith [MS]

"wedde" <weddewu@gmail.com> wrote in message
news:1161339501.677869.240030@f16g2000cwb.googlegroups.com...
>I can use RenderTargetBitmap to get the visual's snapshot, but
> RenderTargetBitmap use software render only. So it is very slow. When I
> get a snapshot of a complicate visual element, it may cost 0.7s. Does
> anyone has the faster way to do this?
>

Thanks a lot for your kindly reply!
I need not manipulate the bitmap. I display the map on my custom
control with many DrawingVisual instances(because I need interact with
each map elements) and I want the user can drag the map to relocate it.
For performance issue, I need a snapshot of my custom control then I
can move the snapshot on my custom control with the mouse.
The VisualBrush will track the changes of the custom control, so it
can't be used on this senario. In fact when I try to use the
VisualBrush, the brush only be filled with the custom control's
background.
I knew these two way only, could you help me? Thank you very much!

"Adam Smith [MS] дµÀ£º
"
> If you want the contents of the Visual to be a bitmap you can manipulate,it
> will have to be in SW eventually (since you aren't allowed to manipulate
> video memory), and RenderTargetBitmap is the way to go. If your scenario
> doesn't involve manipulating/saving the bits, it's possible there are other
> solutions using VisualBrush - can you describe what you're doing with the
> output of the RenderTargetBitmap?
>
> -Adam Smith [MS]
>
> "wedde" <weddewu@gmail.com> wrote in message
> news:1161339501.677869.240030@f16g2000cwb.googlegroups.com...
> >I can use RenderTargetBitmap to get the visual's snapshot, but
> > RenderTargetBitmap use software render only. So it is very slow. When I
> > get a snapshot of a complicate visual element, it may cost 0.7s. Does
> > anyone has the faster way to do this?
> >