List Windows

pToken := Gdip_Startup()

WinGet, list, list
nlist := {}
loop % list
{
    WinGet, style, style, % "ahk_id " list%A_Index%
    Transform, result, BitAnd, %style%, 0x10000000
    if (result != 0)
        nlist.Insert(list%A_Index%)
}

data := {}, totalHeight := maxWidth := 0
loop % nlist.MaxIndex()
{
    x := {}
    x.bitmap := Gdip_BitmapFromHWND(nlist[A_Index])
    Gdip_GetImageDimensions(x.bitmap, width, height)
    x.width := width, x.height := height
    totalHeight += x.height, maxWidth := (A_Index = 1 || x.width > data[A_Index-1].width) ? x.width : maxWidth
    data.Insert(x)
}

pBitmap := Gdip_CreateBitmap(maxWidth, totalHeight), G := Gdip_GraphicsFromImage(pBitmap), y := 0
loop % nlist.MaxIndex()
{
    Gdip_DrawImage(G, data[A_Index].bitmap, 0, y, data[A_Index].width, data[A_Index].height)
    Gdip_DisposeImage(data[A_Index].bitmap)
    y += data[A_Index].height
}
Gdip_SaveBitmapToFile(pBitmap, "AllVisibleWindows.png")
Gdip_DeleteGraphics(G), Gdip_DisposeImage(pBitmap)
Gdip_Shutdown(pToken)