TPlotgrid zeichnet Strich in Polygon

[Stewag]

Leider wird der Path in D11 (in Android) wieder durch den Strich geschlossen
https://www.swiftease.de/download/Sc...011-221811.PNG

Hat jemand eine Idee, wie Rollos obiger T289_Plotgrid Code angepasst werden kann?

Rollo hatte im Sample Code (https://docwiki.embarcadero.com/Code...tGrid_(Delphi))) das Polygon durch einen Pfad ersetzt.
Das hat bis D10 funktioniert.

Hier der zentrale Code (nur Cosinus):

Code:

procedure TForm1.CalculateCos;
var
  I : Integer;
  LPt: TPointF;
  LStr: string;
begin
  FPathData.Clear;

  SetParams;
  SetLength(FPoints, Resolution);                       // Alloc space for number of points to be calculated

  // First point  moveto
  LPt := PointF( Origin.x + Radian * xPixels / Pi,
                 Origin.y - cos(Radian) * yPixels );

  LStr := LStr + 'M'
               + Format('%1.2f', [LPt.X], FFormatSettings)
               + ', '
               + Format('%1.2f', [LPt.Y], FFormatSettings)
               ;

  Radian := Radian + Interval;                        // Set next point

  for I := 1 to High(FPoints) do
  begin

    LPt := PointF( Origin.x + Radian * xPixels / Pi,
                   Origin.y - cos(Radian) * yPixels );

    LStr := LStr + 'L'
                 + Format('%1.2f', [LPt.X], FFormatSettings)
                 + ', '
                 + Format('%1.2f', [LPt.Y], FFormatSettings)
                 ;


    Radian := Radian + Interval;                        // Set next point
  end;

  LStr := LStr + 'M0 0';
  LStr := LStr + 'Z';

  FPathData.Data := LStr;

end;

procedure TForm1.SetParams;
begin
  Resolution := 200;                    // Set resolution to 200 points
  Radian := -2.0 * Pi;                  // Start angle at -2Pi
  xPixels := PlotGrid.Width / 4;        // Contain graph width within a quarter of the grid width (actually half because of neg values)
  yPixels := PlotGrid.Height / 4;       // Contain graph height within a quarter of the grid height (actually half because of neg values)
  Origin := PointF(PlotGrid.Width / 2,  // Calculate the center point of the plot grid
    PlotGrid.Height / 2);
  Interval := 4.0 * Pi / Resolution;    // Set interval between two points in which function values are calculated
end;



procedure TForm1.PlotGridPaint(Sender: TObject; Canvas: TCanvas;
  const ARect: TRectF);
begin
  PlotGrid.Canvas.Stroke.Thickness := 3;                  // Set stroke thickness

  CalculateCos;
  PlotGrid.Canvas.Stroke.Color := TAlphaColorRec.Blue;   // Set color for cos to blue
  PlotGrid.Canvas.DrawPath( FPathData, 1.0 ); // DrawPolygon(FPoints, 1);               // Draw cos graph
end;

[Stewag]

... hier die Lösung, aus https://www.youtube.com/watch?app=de...nnel=QuarkCube

Code:

var
  FPoints: TPolygon;

procedure TfMain.CalculateCos;
var
  i: Integer;
begin
  SetLength(FPoints, Resolution + 1); // Alloc space for number of points to be calculated
  SetParams;
  for i := 0 to High(FPoints) do
  begin
    FPoints[i].X := Origin.X + Radian * xPixels / Pi; // Calculate X value with scaling
    FPoints[i].Y := Origin.Y - cos(Radian) * yPixels; // Calculate Y value (f(X)) with scaling
    Radian := Radian + Interval; // Set next point
  end;
end;

procedure TfMain.PlotGridPaint(Sender: TObject; Canvas: TCanvas; const ARect: TRectF);
var
  i: Integer;
begin
  PlotGrid.Canvas.Stroke.Thickness := 2; // Liniendicke  
  CalculateCos; // hier nur Cosinus
  PlotGrid.Canvas.Stroke.Color := TAlphaColorRec.White;

  for i := 1 to High(FPoints) do
    PlotGrid.Canvas.DrawLine(FPoints[i - 1], FPoints[i], 1);
end;