How do I discover the image-quality settings of a Remote Desktop session?

I am using DevExpress skins. I implemented a switch to disable skins manually. I need this basically because of a Terminal server (I need to have a flat look to save on connection bandwith).

Anyway, the manual switch isn't good because the user must continously use it when using the application locally or remotely. Of course only a user who cares about look.

I would like to leave the manua开发者_如何学Gol switch but to add also another automatic switch that checks the Windows settings for performance (I don't know how to tell this in English, anyway, I mean that setting for performance that lets any version of Windows look, like Windows '98). I would like (if it is possible) to have a unique function that works on every Windows version (2K, XP, Vista, 7, and the server counterparts).

Please note I am not interested in merely knowing whether my system is running in RDP, but whether the performance settings are set for high image quality or not.

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You can use my JwaWinsta unit which is in the Delphi Jedi Apilib.

More specifically you can use WinStationQueryInformationW with the WinStationClient info class which returns a WINSTATIONCLIENT structure.

In this structure is the WinStationClientFlags member which is a bitfield that can contain any mask of the following constant:

  TS_PERF_DISABLE_NOTHING = $0;
  TS_PERF_DISABLE_WALLPAPER = $1;
  TS_PERF_DISABLE_FULLWINDOWDRAG = $2;
  TS_PERF_DISABLE_MENUANIMATIONS = $4;
  TS_PERF_DISABLE_THEMING = $8;
  TS_PERF_ENABLE_ENHANCED_GRAPHICS = $10;
  TS_PERF_DISABLE_CURSOR_SHADOW = $20;
  TS_PERF_DISABLE_CURSORSETTINGS = $40;
  TS_PERF_ENABLE_FONT_SMOOTHING= $80;
  TS_PERF_ENABLE_DESKTOP_COMPOSITION = $100;
  TS_PERF_DEFAULT_NONPERFCLIENT_SETTING = $40000000;
  TS_PERF_RESERVED1 = $80000000;

Further more this structure also returns the ColorDepth member.

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Use the SM_REMOTESESSION System Metric to determine if your program is running over RDP.

This OldNewThing post has much more information.

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Hi You can use WTSEnumerateSessions api to check if the user is running in rdp mode.

var pSessionInfo: PWTS_SESSION_INFOW;
SessionInfo: WTS_SESSION_INFO;
SessionCount: Cardinal;
i: Integer;
begin
  try
    Result := -1;
    if WTSEnumerateSessions(WTS_CURRENT_SERVER_HANDLE, 0, 1, pSessionInfo, SessionCount) then
      begin
        SessionInfo := pSessionInfo^;
        for i := 0 to SessionCount - 1 do
          begin
            if SessionInfo.State = WTSActive then
              begin
                if Pos('rdp', LowerCase(SessionInfo.pWinStationName)) <> 0 then
                  ShowMessage('this is rdp');
              end;
            pSessionInfo := PWTS_SESSION_INFOW(Pointer(Integer(pSessionInfo) + SizeOf(WTS_SESSION_INFOW)));
            SessionInfo := pSessionInfo^;
          end;
      end;
  finally
    WTSFreeMemory(PSessionInfo);
  end;

Hope this answers your question. BTW delphi doesn't have an import for WTSEnumerateSessions, so you will have to import it by hand, or download a Jwa library. The function is decalred in JwaWtsApi32.pas

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// returns the color bit depth (8, 16, 32, ....) on the machine
// note: it works also for rdp (it returns the color bit depth of
// the current session, not some default settings on the server)
function GetBitColorDepth: integer;
var
  DC: THandle;    // display context
begin
  DC := GetDC(HWND(nil));
  Result := GetDeviceCaps(DC, BITSPIXEL);
  ReleaseDC(HWND(nil), DC);
end;