From fdfaa2f99a2c276f6d9aeb954b888112ab9ac552 Mon Sep 17 00:00:00 2001
From: ask <ask@lazarus-ide.org>
Date: Thu, 6 Sep 2012 15:22:10 +0000
Subject: [PATCH] TAChart: Add pie series support to the svg drawer

git-svn-id: trunk@38542 -
---
 components/tachart/tachartutils.pas |  6 +++++
 components/tachart/tadrawersvg.pas  | 38 +++++++++++++++++++++--------
 components/tachart/tageometry.pas   | 10 ++++++++
 3 files changed, 44 insertions(+), 10 deletions(-)

diff --git a/components/tachart/tachartutils.pas b/components/tachart/tachartutils.pas
index 52decbfc38..032189dde0 100644
--- a/components/tachart/tachartutils.pas
+++ b/components/tachart/tachartutils.pas
@@ -259,6 +259,7 @@ const
 
 function BoundsSize(ALeft, ATop: Integer; ASize: TSize): TRect; inline;
 
+function Deg16ToRad(ADeg16: Integer): Double; inline;
 function DoubleInterval(AStart, AEnd: Double): TDoubleInterval; inline;
 
 procedure Exchange(var A, B: Integer); overload; inline;
@@ -317,6 +318,11 @@ begin
   Result := Bounds(ALeft, ATop, ASize.cx, ASize.cy);
 end;
 
+function Deg16ToRad(ADeg16: Integer): Double;
+begin
+  Result := DegToRad(ADeg16 / 16);
+end;
+
 function DoubleInterval(AStart, AEnd: Double): TDoubleInterval;
 begin
   Result.FStart := AStart;
diff --git a/components/tachart/tadrawersvg.pas b/components/tachart/tadrawersvg.pas
index 0d4bfef5f0..4ee6497dad 100644
--- a/components/tachart/tadrawersvg.pas
+++ b/components/tachart/tadrawersvg.pas
@@ -96,6 +96,8 @@ uses
 const
   RECT_FMT =
     '<rect x="%d" y="%d" width="%d" height="%d" style="%s"/>';
+var
+  fmtSettings: TFormatSettings;
 
 function ColorToHex(AColor: TFPColor): String;
 begin
@@ -108,6 +110,16 @@ begin
       Result := Format('#%.2x%.2x%.2x', [red shr 8, green shr 8, blue shr 8]);
 end;
 
+function DP2S(AValue: TDoublePoint): String;
+begin
+  Result := Format('%g,%g', [AValue.X, AValue.Y], fmtSettings);
+end;
+
+function F2S(AValue: Double): String;
+begin
+  Result := FloatToStr(AValue, fmtSettings);
+end;
+
 { TSVGDrawer }
 
 procedure TSVGDrawer.AddToFontOrientation(ADelta: Integer);
@@ -226,16 +238,11 @@ begin
 end;
 
 function TSVGDrawer.OpacityStr: String;
-var
-  fs: TFormatSettings;
 begin
   if FTransparency = 0 then
     Result := ''
-  else begin
-    fs := DefaultFormatSettings;
-    fs.DecimalSeparator := '.';
-    Result := FloatToStr((255 - FTransparency) / 256, fs);
-  end;
+  else
+    Result := F2S((255 - FTransparency) / 256);
 end;
 
 function TSVGDrawer.PointsToStr(
@@ -276,10 +283,16 @@ end;
 
 procedure TSVGDrawer.RadialPie(
   AX1, AY1, AX2, AY2: Integer; AStartAngle16Deg, AAngleLength16Deg: Integer);
+var
+  e: TEllipse;
+  p1, p2: TDoublePoint;
 begin
-  Unused(AX1, AY1);
-  Unused(AX2, AY2);
-  Unused(AStartAngle16Deg, AAngleLength16Deg);
+  e.InitBoundingBox(AX1, AY1, AX2, AY2);
+  p1 := e.GetPoint(Deg16ToRad(AStartAngle16Deg));
+  p2 := e.GetPoint(Deg16ToRad(AStartAngle16Deg + AAngleLength16Deg));
+  WriteFmt(
+    '<path d="M%s L%s A%s 0 0,0 %s Z" style="%s"/>',
+    [DP2S(e.FC), DP2S(p1), DP2S(e.FR), DP2S(p2), StyleFill + StyleStroke]);
 end;
 
 procedure TSVGDrawer.Rectangle(AX1, AY1, AX2, AY2: Integer);
@@ -399,5 +412,10 @@ begin
   FStream.WriteBuffer(le[1], Length(le));
 end;
 
+initialization
+
+  fmtSettings := DefaultFormatSettings;
+  fmtSettings.DecimalSeparator := '.';
+
 end.
 
diff --git a/components/tachart/tageometry.pas b/components/tachart/tageometry.pas
index 2584cbe4ae..9225beb416 100644
--- a/components/tachart/tageometry.pas
+++ b/components/tachart/tageometry.pas
@@ -29,6 +29,8 @@ type
     FC: TDoublePoint;
     FR: TDoublePoint;
     constructor InitBoundingBox(AX1, AY1, AX2, AY2: Integer);
+  public
+    function GetPoint(AParametricAngle: Double): TDoublePoint;
   end;
 
 function CopyPoints(
@@ -520,6 +522,14 @@ end;
 
 { TEllipse }
 
+function TEllipse.GetPoint(AParametricAngle: Double): TDoublePoint;
+var
+  s, c: Extended;
+begin
+  SinCos(AParametricAngle, s, c);
+  Result := DoublePoint(c, -s) * FR + FC;
+end;
+
 constructor TEllipse.InitBoundingBox(AX1, AY1, AX2, AY2: Integer);
 begin
   FC.X := (AX1 + AX2) / 2;