--- C:/projects/Components/JVCL/jvcl/run/JvChart.pas Tue May 6 11:48:52 2014 +++ C:/projects/Components/JVCL/jvcl/run/JvChart - DM line fill 2.pas Tue Aug 19 19:05:42 2014 @@ -19,6 +19,7 @@ Contributor(s): Warren Postma (warrenpstma att hotmail dott com) Mårten Henrichson/AABSoft (no email known) + David Millington (vintagedave att gmail dott com) Contains some code which is (C) 1996-1998 AABsoft and Mårten Henrichson @@ -83,6 +84,7 @@ - Calls only JclMath.IsNaN, not Math.IsNaN, which doesn't exist on older Delphi/BCB versions. - Added CopyFloatingMarkers (thought I did that yesterday but missed it) + 2014-08-19 - DM - Added area graph option (ie, filling under the line of a line graph) You may retrieve the latest version of this file at the Project JEDI's JVCL home page, located at http://jvcl.delphi-jedi.org @@ -470,6 +472,7 @@ FXAxisDivisionMarkers: Boolean; // Do you want grid-paper look? FXAxisHeader: string; FMarkerSize:Integer; + FFillUnderLine : Boolean; // New 2014 FXLegends: TStringList; // Text labels. FXLegendMaxTextWidth: Integer; // runtime: display width (pixels) of widest string in FXLegends[1:X]. FXAxisValuesPerDivision: Integer; @@ -603,6 +606,7 @@ { Y Range } { plotting markers } property MarkerSize: Integer read FMarkerSize write FMarkerSize default JvChartDefaultMarkerSize; + property FillUnderLine : Boolean read FFillUnderLine write FFillUnderLine default False; { !! New: Primary (left side) Y axis, and Secondary (right side) Y Axis !!} property PrimaryYAxis: TJvChartYAxisOptions read FPrimaryYAxis write SetPrimaryYAxis; property SecondaryYAxis: TJvChartYAxisOptions read FSecondaryYAxis write SetSecondaryYAxis; @@ -1827,6 +1831,7 @@ FPenColors[11] := clAqua; FChartKind := ckChartLine; + FFillUnderLine := false; FPenCount := 1; @@ -2730,18 +2735,20 @@ ACanvas.Brush.Style := bsClear; { NEW: Box around entire chart area. } - X1 := Round(XOrigin); - X2 := Round(Options.XStartOffset + Options.XPixelGap * VC); - Y1 := Options.YStartOffset - 1; - Y2 := Round(YOrigin) + 1; // was YTempOrigin + if Options.AxisLineWidth <> 0 then begin + X1 := Round(XOrigin); + X2 := Round(Options.XStartOffset + Options.XPixelGap * VC); + Y1 := Options.YStartOffset - 1; + Y2 := Round(YOrigin) + 1; // was YTempOrigin - if Y2 > Height then - begin - // I suspect that the value of YPixelGap is too large in some cases. - Options.PrimaryYAxis.Normalize; - //OutputDebugString( PChar('Y2 is bogus. PYVC='+IntToStr(PYVC)) ); + if Y2 > Height then + begin + // I suspect that the value of YPixelGap is too large in some cases. + Options.PrimaryYAxis.Normalize; + //OutputDebugString( PChar('Y2 is bogus. PYVC='+IntToStr(PYVC)) ); + end; + MyRectangle(ACanvas, X1, Y1, X2, Y2); end; - MyRectangle(ACanvas, X1, Y1, X2, Y2); ACanvas.Brush.Style := bsSolid; end; @@ -2752,6 +2759,8 @@ var ACanvas: TCanvas; begin + if Options.AxisLineWidth = 0 then Exit; + ACanvas := GetChartCanvas(false); ACanvas.Pen.Style := psSolid; ACanvas.Pen.Color := Options.AxisLineColor; @@ -2767,8 +2776,9 @@ var LCanvas: TCanvas; begin + if Options.AxisLineWidth = 0 then Exit; + LCanvas := GetChartCanvas(false); - LCanvas.Pen.Style := psSolid; LCanvas.Pen.Color := Options.AxisLineColor; LCanvas.Pen.Width := Options.AxisLineWidth; // was missing. Added Feb 2005. -WPostma. @@ -3310,7 +3320,6 @@ end; // Keep Y in visible chart range: - function GraphConstrainedLineY(Pen, Sample: Integer): Double; var V: Double; @@ -3336,6 +3345,26 @@ Result := Options.YStartOffset - 2; // Not quite good enough, but better than before. end; + function GetUnderLineFillColor(const A, B: TColor) : TColor; + const + Lerp = 0.85; // 0-1, where 0 is fully A and 1 is fully B. This value seems good + var + AR, AG, AB, BR, BG, BB: Byte; + begin + AR := GetRValue(A); + AG := GetGValue(A); + AB := GetBValue(A); + BR := GetRValue(B); + BG := GetGValue(B); + BB := GetBValue(B); + + Result := RGB( + Round(AR + Lerp * (BR - AR)), + Round(AG + Lerp * (BG - AG)), + Round(AB + Lerp * (BB - AB)) + ); + end; + procedure PlotGraphChartLine; var I, I2, J, Y1: Integer; @@ -3359,6 +3388,7 @@ // No line types? if Options.PenStyle[I] = psClear then Continue; + SetLineColor(ACanvas, I); J := 0; V := GraphConstrainedLineY(I, J); @@ -3406,8 +3436,9 @@ end; end; end; + //OldV := V; // keep track of last valid value, for handling gaps. + MyPenLineTo(ACanvas, Round(XOrigin + J * LineXPixelGap), Y); - //OldV := V; // keep track of last valid value, for handling gaps. end; end; end; @@ -3417,6 +3448,103 @@ SetLineColor(ACanvas, jvChartAxisColorIndex); end; + procedure PlotGraphChartLineFill; + var + I, I2, J, Y1: Integer; + V, LineXPixelGap: Double; + NanFlag: Boolean; + VC: Integer; + FillPoints : array of TPoint; + FillPolyIndex : Integer; + begin + Assert(Assigned(ACanvas)); + Assert(Assigned(ACanvas.Brush)); + + SetLength(FillPoints, 0); // Not set to 0 by compiler + try + VC := Options.XValueCount; + if VC < 2 then + VC := 2; + LineXPixelGap := ((Options.XEnd - 2) - Options.XStartOffset) / (VC - 1); + + for I := 0 to Options.PenCount - 1 do + begin + // No line types? + if Options.PenStyle[I] = psClear then + Continue; + + SetLength(FillPoints, FData.ValueCount + 2 {start and end points}); + FillPolyIndex := 0; + + J := 0; + V := GraphConstrainedLineY(I, J); + NanFlag := IsNaN(V); + if not NanFlag then + begin + Y := Round(V); + FillPoints[FillPolyIndex] := Point(Round(XOrigin)+1, Round(YOrigin)); // start at origin + Inc(FillPolyIndex); + FillPoints[FillPolyIndex] := Point(Round(XOrigin)+1, Y); // add first point + Inc(FillPolyIndex); + end; + + for J := 1 to Options.XValueCount - 1 do + begin + V := GraphConstrainedLineY(I, J); + if IsNaN(V) then + begin + NanFlag := True; // skip. + FillPoints[FillPolyIndex] := Point(Round(XOrigin + J * LineXPixelGap), Round(YOrigin)); // !!! DEBUG + Inc(FillPolyIndex); + end + else + begin + if NanFlag then + begin // resume, valid value. + NanFlag := False; + Y := Round(V); + // pick up the pen and slide forward + FillPoints[FillPolyIndex] := Point(Round(XOrigin + J * LineXPixelGap), Y); + Inc(FillPolyIndex); + end + else + begin + Y := Round(V); + if I > 0 then + begin + for I2 := 0 to I - 1 do + begin + V := GraphConstrainedLineY(I2, J); + if IsNaN(V) then + Continue; + end; + end; + + FillPoints[FillPolyIndex] := Point(Round(XOrigin + J * LineXPixelGap), Y); // add next point + Inc(FillPolyIndex); + end; + end; + end; + + // Add a final point which is the same as the last, but at the bottom + if FillPolyIndex > 0 then begin + FillPoints[FillPolyIndex] := Point(FillPoints[FillPolyIndex-1].X, Round(YOrigin)); + Inc(FillPolyIndex); + SetLength(FillPoints, FillPolyIndex); // Trim to the actual usage + + // First draw the fill + ACanvas.Pen.Style := psClear; + ACanvas.Brush.Color := GetUnderLineFillColor(Options.PenColor[I], + Options.PenColor[jvChartPaperColorIndex]); + ACanvas.Brush.Style := bsSolid; + ACanvas.Polygon(FillPoints); + end; + end; + finally + SetLength(FillPoints, 0); + end; + end; + procedure PlotGraphStackedBarAverage; var I, J: Integer; @@ -3621,8 +3749,11 @@ PlotGraphBar; ckChartStackedBar: PlotGraphStackedBar; - ckChartLine: //, ckChartLineWithMarkers: - PlotGraphChartLine; + ckChartLine: begin//, ckChartLineWithMarkers: + if Options.FillUnderLine then + PlotGraphChartLineFill; // Do this before drawing lines, so lines are always visible + PlotGraphChartLine; + end; ckChartMarkers: PlotGraphChartMarkers; ckChartStackedBarAverage: @@ -5223,6 +5354,8 @@ procedure TJvChart.MyAxisLineTo(ACanvas: TCanvas; X, Y: Integer); begin + if Options.AxisLineWidth = 0 then Exit; + ACanvas.Pen.Width := Options.AxisLineWidth; ACanvas.LineTo(X, Y); ACanvas.Pen.Width := 1;