enumerate windows alt-tab does

i'm formulating an alt-tab deputy perspective nonetheless i have problems register active programs.

i'm controlling enumwindows list windows, nonetheless list huge. contains 400 equipment i wholly have 10 windows open. seems hwnd each unparalleled control lot stuff.

so i have filter list somehow, nonetheless i can't control accurately alt-tab does.

this formula i filter list right now. works graceful well, nonetheless i neglected windows removed tool-windows visible studio i also skip windows itunes warcraft3.

private bool shouldwindowbedisplayed(intptr window)
{
    uint windowstyles = win32.getwindowlong(window, gwl.gwl_style);

    (((uint)windowstyles.ws_visible & windowstyles) != (uint)windowstyles.ws_visible ||
        ((uint)windowexstyles.ws_ex_appwindow & windowstyles) != (uint)windowexstyles.ws_ex_appwindow)
    {
        relapse true;
    }
    relapse false;
}