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wisepenguin



Joined: 30 Mar 2005
Posts: 129
wisepenguin
i am calling GetCursorPos to get the current mouse position so i can call TrackPopupMenu.
instead of using a global variable POINT, i made room on the stack then did this

Code:
virtual at esp
.curpos POINT
end virtual

lea ebx, [.curpos]
push ebx
call [GetCursorPos]
    


however, the popup menu is placed in the bottom left of screen (0, 0 coordinates).

if i change it to

Code:
lea esi, [esp]
virtual at ESI
    

...same as above

it works and the menu is placed correctly.

now, i thought esi will be the same value as esp because of the LEA instruction so i dont understand how using LEA and ESI makes the code work.

am i doing something wrong ?

i used
Code:
virtual at esp
.wc WNDCLASSEX
end virtual
    


to set window class properties and RegisterClassEx with the WNDCLASSEX on the stack and that works. thats why i cant understand why it doesnt work with the GetCursorPos.[/code]
Post 11 Aug 2005, 23:04
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17716
Location: In your JS exploiting you and your system
revolution
Try this:
Code:
virtual at esp
.curpos POINT
end virtual

sub esp,sizeof.POINT
lea ebx, [.curpos] ;you can also use "mov ebx,esp" here
push ebx
call [GetCursorPos]
... ;here is some code using ebx that points to .curpos
add esp,sizeof.POINT ;we're finished with .curpos    
Post 12 Aug 2005, 02:54
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