Knob value wie feiner abstimmen

[EWeiss]

Jemand eine Idee wie ich mein Knob Controll noch feiner abstimmen kann?
Benutze schon single aber das scheint nicht auszureichen
da beim drehen der Knobs es sehr schwierig ist die benötigte Value zu treffen.
Manchmal springt es einfach 2 Frames weiter vor allem dann wenn ein ImageStrip wie bei Speed 300 Bilder enthält.

Gibt es da noch was akurateres als Single?

Delphi-Quellcode:

const
  KNOB_HORZ = -1;
  KNOB_VERT =  0;
  KNOB_NONE =  1;

  KNOB_GAP          = 45  * pi / 180;
  KNOB_ANGLE_RANGE  = 2   * pi {360°} - KNOB_GAP;
  KNOB_OFFSET_ANGLE = 0.5 * pi {90°, also "unten"} + 0.5 * KNOB_GAP;

  KNOB_IMAGE         = 1;
  KNOB_MINVAL        = 2;
  KNOB_MAXVAL        = 3;
  KNOB_VALUE         = 4;
  KNOB_MOVING        = 5;
  KNOB_WAS_VALUE     = 6;
  KNOB_DEFAULT_VALUE = 7;

Delphi-Quellcode:

function ValueFromAngle(Angle: single): single;
var
  RelativeAngle: single;
begin
  RelativeAngle := Angle - KNOB_OFFSET_ANGLE;
  if RelativeAngle < 0 then
    RelativeAngle := RelativeAngle + 2 * pi;

  Result := (RelativeAngle) / KNOB_ANGLE_RANGE;
  if Result > 1.0 then
    if RelativeAngle < 0.5 * KNOB_ANGLE_RANGE + pi then
      Result := 1
    else
      Result := 0
end;

procedure UpdateFramePosition(WinHandle: HWND);
var
  Img, imgW, imgH:  cardinal;
begin
  //with SkinEngine do
  //begin
    Img := SkinEngine.GetProperty(WinHandle, KNOB_IMAGE);
    SkinEngine.GetImageSize(Img, imgW, imgH);

    XOffset   := FFrame mod tmax;
    YOffset   := FFrame div tmax;
    dXOffset  := integer(imgW) div tmax;
    dYOffset  := 0;
  //end;

end;

procedure SetKnobLocation(WinHandle: HWND; x, y: single);
var
  rc:               TRect;
  Img, imgW, imgH:  cardinal;

begin

  //with SkinEngine do
  //begin

    GetClientRect(WinHandle, rc);

    Img := SkinEngine.GetProperty(WinHandle, KNOB_IMAGE);
    SkinEngine.GetImageSize(Img, imgW, imgH);

    tMin := SkinEngine.GetProperty(WinHandle, KNOB_MINVAL);
    tMax := SkinEngine.GetProperty(WinHandle, KNOB_MAXVAL);

    Angle := arctan2(y - rc.Bottom div 2, x - rc.Right div 2);
    Value := ValueFromAngle(Angle) * tMax ;

    FFrame := round(Value) mod tMax;
    UpdateFramePosition(WinHandle);


    SkinEngine.SetProperty(WinHandle, KNOB_VALUE, round(Value));
    if Value <> SkinEngine.GetProperty(WinHandle, KNOB_WAS_VALUE) then
    begin
      SkinEngine.FUpdateWindow(WinHandle, False);
      SetToolTipText(WinHandle, PWideChar(IntToStr(round(Value))));
    end;

    SkinEngine.SetProperty(WinHandle, KNOB_WAS_VALUE, round(Value));
  //end;

end;

// Berechne die X, Y koordinaten abhängig von der aktuellen tVal
procedure GetKnobLocation(WinHandle: HWND);
var
  Img, imgW, imgH: cardinal;
begin

  //with SkinEngine do
  //begin
    Img := SkinEngine.GetProperty(WinHandle, KNOB_IMAGE);
    SkinEngine.GetImageSize(Img, imgW, imgH);
    tMax := SkinEngine.GetProperty(WinHandle, KNOB_MAXVAL);
    Value := SkinEngine.GetProperty(WinHandle, KNOB_VALUE);
    if Value <= (tMax - 1) then
    begin
      FFrame := round(Value) mod tMax;
      UpdateFramePosition(WinHandle);
    end else
    begin
       FFrame := round(Value - 1) mod tMax;
       UpdateFramePosition(WinHandle);
    end;
  //end;

end;

// Default Value setzen
procedure SetKnobDefaultValue(WinHandle: HWND; tVal: Integer);

begin

  //with SkinEngine do
  //begin
    tMin := SkinEngine.GetProperty(WinHandle, KNOB_MINVAL);
    tMax := SkinEngine.GetProperty(WinHandle, KNOB_MAXVAL);
    if tMin > tMax then
      SWAP(tMin, tMax);

    tVal := MIN(MAX(tMin, tVAL), tMax);
    if tVal <> SkinEngine.GetProperty(WinHandle, KNOB_VALUE) then
    begin
      SkinEngine.SetProperty(WinHandle, KNOB_VALUE, tVal);
      SkinEngine.SetProperty(WinHandle, KNOB_WAS_VALUE, tVal);

      SkinEngine.FUpdateWindow(WinHandle, False);
    end;
  //end;

end;