how to deal with this repaint case?(on remote screen transmit) [Archive]

微软新闻组

04-11-04, 03:51 PM

something

i want to abtain remote screen capture on the pc in LAN.
i was suggested to transmit the changed parts only to save the bandwidth.
so i divide the screen into 10*10 parts. and now , i need to display the
remote screen on my own form. my method is use this:

Graphics c = this.createGraphics();
c.drawImage(imageparts,xcoodinary,ycoodinary);// imageparts is ONE part
// of the screen (1/100)

whenever i receive a imageparts, i use the code above to draw the changed
screen parts on a FORM. the code seems to work well.In the first time,i
should call this code 100 times to get the original screen.after then , i
could only call this code several times.

but now ,when the FORM is changed or covered by other windows , with the
repaint result ,the image disappeared or changed into a wrong display.

So i should put the code above into OnPaint method. but the code above only
redraws the changed parts of the remote screen, the others disappeared.

How can i redraw the previous unchanged image already on the FORM ? OR are
there other methods to solve this problem ?

THX!

Michael Giagnocavo [MVP]

04-13-04, 06:42 PM

something

You should create a backing store on the client, say a bitmap. This bitmap
stores the "screen". When new pieces of the screen come in, you paint them
to the form AND the bitmap. OnPaint, you paint the entire bitmap.

-mike
MVP

"微软新闻组" <fpe2000@163.net> wrote in message
news:%23CC9G%237HEHA.2712@TK2MSFTNGP10.phx.gbl...
>i want to abtain remote screen capture on the pc in LAN.
> i was suggested to transmit the changed parts only to save the bandwidth.
> so i divide the screen into 10*10 parts. and now , i need to display the
> remote screen on my own form. my method is use this:
>
> Graphics c = this.createGraphics();
> c.drawImage(imageparts,xcoodinary,ycoodinary);// imageparts is ONE part
> // of the screen (1/100)
>
> whenever i receive a imageparts, i use the code above to draw the changed
> screen parts on a FORM. the code seems to work well.In the first time,i
> should call this code 100 times to get the original screen.after then , i
> could only call this code several times.
>
> but now ,when the FORM is changed or covered by other windows , with the
> repaint result ,the image disappeared or changed into a wrong display.
>
> So i should put the code above into OnPaint method. but the code above
> only
> redraws the changed parts of the remote screen, the others disappeared.
>
> How can i redraw the previous unchanged image already on the FORM ? OR are
> there other methods to solve this problem ?
>
> THX!
>
>