Paintbox Hintergrundfarbe

[Larsi]

Wenn ich die Rectangle Sachen auskommentiere dann kommt einmal der Effekt dass wie du schon gesagt hast die Balken immer da bleiben aber die Hintergrundfarbe ist immernoch weiß. Vielleicht wisst ihr ja weiter. Hier der Code der Spectrum Vis: (Habe alle meine Änderungen rausgenommen da das wahrscheinlich nicht richtig war)

Delphi-Quellcode:

unit spectrum_vis;
{ Spectrum Visualyzation by Alessandro Cappellozza
  version 0.8 05/2002
  [url]http://digilander.iol.it/Kappe/audioobject[/url]
}

interface
  uses Windows, Dialogs, Graphics, SysUtils, CommonTypes, Classes, BassDLLPlayer;

 type TSpectrum = Class(TObject)
    private
      VisBuff : TBitmap;
      BackBmp : TBitmap;

      BkgColor : TColor;
      SpecHeight : Integer;
      PenColor : TColor;
      PeakColor: TColor;
      DrawType : Integer;
      DrawRes  : Integer;
      FrmClear : Boolean;
      UseBkg   : Boolean;
      PeakFall : Integer;
      LineFall : Integer;
      ColWidth : Integer;
      ShowPeak : Boolean;

       FFTPeacks  : array [0..128] of Integer;
       FFTFallOff : array [0..128] of Integer;

    public
     Constructor Create (Width, Height : Integer);
     procedure Draw(HWND : THandle; FFTData : TFFTData; X, Y : Integer);
     procedure SetBackGround (Active : Boolean; BkgCanvas : TGraphic);

     property BackColor : TColor read BkgColor write BkgColor;
     property Height : Integer read SpecHeight write SpecHeight;
     property Width  : Integer read ColWidth write ColWidth;
     property Pen  : TColor read PenColor write PenColor;
     property Peak : TColor read PeakColor write PeakColor;
     property Mode : Integer read DrawType write DrawType;
     property Res  : Integer read DrawRes write DrawRes;
     property FrameClear : Boolean read FrmClear write FrmClear;
     property PeakFallOff: Integer read PeakFall write PeakFall;
     property LineFallOff: Integer read LineFall write LineFall;
     property DrawPeak   : Boolean read ShowPeak write ShowPeak;
  end;

 var Spectrum : TSpectrum;

implementation

     Constructor TSpectrum.Create(Width, Height : Integer);
      begin
        VisBuff := TBitmap.Create;
        BackBmp := TBitmap.Create;

          VisBuff.Width := Width;
          VisBuff.Height := Height;
          BackBmp.Width := Width;
          BackBmp.Height := Height;

         BkgColor := clBlack;
          SpecHeight := 100;
          PenColor := clWhite;
          PeakColor := clYellow;
          DrawType := 0;
          DrawRes  := 1;
          FrmClear := True;
          UseBkg := False;
          PeakFall := 1;
          LineFall := 3;
          ColWidth := 5;
          ShowPeak := True; 
      end;

     procedure TSpectrum.SetBackGround (Active : Boolean; BkgCanvas : TGraphic);
      begin
        UseBkg := Active;
        BackBmp.Canvas.Draw(0, 0, BkgCanvas);
      end;

     procedure TSpectrum.Draw(HWND : THandle; FFTData : TFFTData; X, Y : Integer);
        var i, YPos : LongInt; YVal : Single;
       begin

       if FrmClear then begin
          VisBuff.Canvas.Pen.Color := BkgColor;
          VisBuff.Canvas.Brush.Color := BkgColor;
        VisBuff.Canvas.Rectangle(0, 0, VisBuff.Width, VisBuff.Height);
          if UseBkg then VisBuff.Canvas.CopyRect(Rect(0, 0, BackBmp.Width, BackBmp.Height), BackBmp.Canvas, Rect(0, 0, BackBmp.Width, BackBmp.Height));
       end;

        VisBuff.Canvas.Pen.Color := PenColor;
         for i := 0 to 128 do begin
           YVal := Abs(FFTData[(i * DrawRes) + 5]);
           YPos := Trunc((YVal) * 500);
           if YPos > Height then YPos := SpecHeight;

           if YPos >= FFTPeacks[i] then FFTPeacks[i] := YPos
              else FFTPeacks[i] := FFTPeacks[i] - PeakFall;

           if YPos >= FFTFallOff[i] then FFTFallOff[i] := YPos
              else FFTFallOff[i] := FFTFallOff[i] - LineFall;

              if (VisBuff.Height - FFTPeacks[i]) > VisBuff.Height then FFTPeacks[i] := 0;
              if (VisBuff.Height - FFTFallOff[i]) > VisBuff.Height then FFTFallOff[i] := 0;

              case DrawType of
                0 : begin
                       VisBuff.Canvas.MoveTo(X + i, Y + VisBuff.Height);
                       VisBuff.Canvas.LineTo(X + i, Y + VisBuff.Height - FFTFallOff[i]);
                       if ShowPeak then VisBuff.Canvas.Pixels[X + i, Y + VisBuff.Height - FFTPeacks[i]] := Pen;
                    end;

                1 : begin
                     if ShowPeak then VisBuff.Canvas.Pen.Color := PeakColor;
                     if ShowPeak then VisBuff.Canvas.MoveTo(X + i * (ColWidth + 1), Y + VisBuff.Height - FFTPeacks[i]);
                     if ShowPeak then VisBuff.Canvas.LineTo(X + i * (ColWidth + 1) + ColWidth, Y + VisBuff.Height - FFTPeacks[i]);

                     VisBuff.Canvas.Pen.Color := PenColor;
                     VisBuff.Canvas.Brush.Color := PenColor;
                    VisBuff.Canvas.Rectangle(X + i * (ColWidth + 1), Y + VisBuff.Height - FFTFallOff[i], X + i * (ColWidth + 1) + ColWidth, Y + VisBuff.Height);
                    end;
              end;
         end;

          BitBlt(HWND, 0, 0, VisBuff.Width, VisBuff.Height, VisBuff.Canvas.Handle, 0, 0, srccopy)
       end;
end.