Why does the checksum value of the region of a window changes when the window moves to a another location

[majiangtian]

$t="迅雷"
WinActivate($t)
MouseMove(@DesktopWidth,@DesktopHeight,0)
Sleep(1000)
$r=WinGetPos($t)
ConsoleWrite("postion 0 checksum=" & PixelChecksum($r[0],$r[1],$r[0]+$r[2]-1,$r[1]+$r[3]-1) & @CRLF)
WinMove($t,"",$r[0]-15,$r[1]-15,$r[2],$r[3])
Sleep(1000)
$r=WinGetPos($t)
ConsoleWrite("postion 1 checksum=" & PixelChecksum($r[0],$r[1],$r[0]+$r[2]-1,$r[1]+$r[3]-1) & @CRLF)

[martin]

That's a good question.

I played with that a bit and found (On my XP laptop at least) that if you make sure your rectangle doesn't go outside

 Left + 1, Top + 5, Right - 1, Bottom - 1

then it works as expected, otherwise the results don't appear to make sense. I can't see what changes in the borders when the window is moved.

Here is what I used. (Of course you must make sure that the whole window stays within the desktop.)

$l = 1
$p = 5
$g = 1
$b = 1

opt("pixelcoordmode",1)
$t = "Untitled - Notepad"
WinActivate($t)
MouseMove(@DesktopWidth,@DesktopHeight,1)
Sleep(1000)
$r=WinGetPos($t)
ConsoleWrite("postion 0 checksum=" & PixelChecksum($r[0]+$l,$r[1]+$p,$r[0]+$r[2]-$g,$r[1]+$r[3]-$b) & @CRLF)
WinMove($t,"",$r[0]-15,$r[1]-15);,$r[2],$r[3])
Sleep(1000)
$r=WinGetPos($t)
ConsoleWrite("postion 0 checksum=" & PixelChecksum($r[0]+$l,$r[1]+$p,$r[0]+$r[2]-$g,$r[1]+$r[3]-$b) & @CRLF)

Edited November 18, 2013 by martin