Using DllStructCreate

[Lej]

Trying to learn a bit about how to use dll commands, structs etc.

This is supposed to draw a purple square.

Why does this work when I use $RectRgn2[0] but not when it's $RectRgn1Pointer?

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[Uten]

Since there are no takers on this I'll throw in some thoughts. I can't test at the moment so regard this for what it is, thoughts.

According to this sample on codeprohect (the first thing that came up from google)

BOOL FillRgn(
  HDC hdc,  // handle to device context
  HRGN hrgn,  // handle to region to be filled
  HBRUSH hbr  // handle to brush used to fill the region
);

So I guess the reason is that you pass on a long (which should work), but I have found from experience that it it's worth to try with ptr if stuff goes wrong. So (again untested):

DllCall("gdi32.dll", "long", "FillRgn", "long", $hDC[0], "ptr", $RectRgn1Pointer, "long", $hBrush[0])oÝ÷ Ø(ºWZÊ-º0{(ç«®Üç$x¡×¢|³*.Ù^jËZ²Z'«2¢êâ׬·÷^nè&¡×¢g­)à)jëh×6chk(DllCall("gdi32.dll", "long", "FillRgn", "long", $hDC[0], "ptr", $RectRgn1Pointer, "long", $hBrush[0]))

Func chk($val, $erl=@ScriptLineNumber, $err=@Error, $ext=@Extended)
    If $err <> 0 OR $ext <> 0 Then 
        ConsoleWrite("(" & $erl & ") := (" & $err & ")(" & $ext & ")" & @LF)
        Return SetError($err, $xt, $val)
    EndIf
    Return $val
EndFunc