From 9121096235813436cfeb1cbb4d504934acb5f147 Mon Sep 17 00:00:00 2001
From: ask <ask@lazarus-ide.org>
Date: Sun, 23 Jun 2013 19:50:36 +0000
Subject: [PATCH] TAChart: Initial implementation of diagram decorators

git-svn-id: trunk@41857 -
---
 components/tachart/tadiagram.pas        | 104 ++++++++++++++++++++++++
 components/tachart/tadiagramdrawing.pas |  34 +++++++-
 2 files changed, 134 insertions(+), 4 deletions(-)

diff --git a/components/tachart/tadiagram.pas b/components/tachart/tadiagram.pas
index e274ff3b17..bf4732fd84 100644
--- a/components/tachart/tadiagram.pas
+++ b/components/tachart/tadiagram.pas
@@ -47,6 +47,40 @@ type
 
   TDiaElement = class;
 
+  TDiaDecoratorList = class;
+
+  TDiaDecorator = class(TDiaObject)
+  private
+    FOwner: TDiaObject;
+  public
+    constructor Create(AOwner: TDiaDecoratorList);
+    property Owner: TDiaObject read FOwner;
+  end;
+
+  TDiaDecoratorEnumerator = class;
+
+  TDiaDecoratorList = class(TDiaObject)
+  private
+    FDecorators: array of TDiaDecorator;
+    FOwner: TDiaObject;
+    procedure Add(ADecorator: TDiaDecorator);
+  public
+    constructor Create(AOwner: TDiaObject);
+    destructor Destroy; override;
+    property Owner: TDiaObject read FOwner;
+    function GetEnumerator: TDiaDecoratorEnumerator;
+  end;
+
+  TDiaDecoratorEnumerator = class
+    FList: TDiaDecoratorList;
+    FPosition: Integer;
+  public
+    constructor Create(AList: TDiaDecoratorList);
+    function GetCurrent: TDiaDecorator;
+    function MoveNext: Boolean;
+    property Current: TDiaDecorator read GetCurrent;
+  end;
+
   TDiagram = class(TDiaObject)
   strict private
     FBounds: array [TDiaBoxSide] of TDiaCoordinate;
@@ -74,13 +108,17 @@ type
     FConnectors: array of TDiaConnector;
     FOwner: TDiagram;
   private
+    FDecorators: TDiaDecoratorList;
     procedure SetOwner(AValue: TDiagram);
   public
+    constructor Create;
+    destructor Destroy; override;
     procedure Add(AConnector: TDiaConnector);
     procedure Changed(ASender: TDiaObject); override;
     procedure Draw; virtual;
     procedure Notify(ASender: TDiaObject); override;
     property Owner: TDiagram read FOwner;
+    property Decorators: TDiaDecoratorList read FDecorators;
   end;
 
   TDiaPosition = class(TDiaObject)
@@ -218,6 +256,61 @@ begin
   Result.Y := WeightedAverage(AP1.Y, AP2.Y, ACoeff);
 end;
 
+{ TDiaDecoratorEnumerator }
+
+constructor TDiaDecoratorEnumerator.Create(AList: TDiaDecoratorList);
+begin
+  FList := AList;
+  FPosition := -1;
+end;
+
+function TDiaDecoratorEnumerator.GetCurrent: TDiaDecorator;
+begin
+  Result := FList.FDecorators[FPosition];
+end;
+
+function TDiaDecoratorEnumerator.MoveNext: Boolean;
+begin
+  FPosition += 1;
+  Result := FPosition < Length(FList.FDecorators);
+end;
+
+{ TDiaDecoratorList }
+
+procedure TDiaDecoratorList.Add(ADecorator: TDiaDecorator);
+begin
+  SetLength(FDecorators, Length(FDecorators) + 1);
+  FDecorators[High(FDecorators)] := ADecorator;
+  //Notify(ADecorator);
+end;
+
+constructor TDiaDecoratorList.Create(AOwner: TDiaObject);
+begin
+  FOwner := AOwner;
+end;
+
+destructor TDiaDecoratorList.Destroy;
+var
+  d: TDiaDecorator;
+begin
+  for d in FDecorators do
+    d.Free;
+  inherited;
+end;
+
+function TDiaDecoratorList.GetEnumerator: TDiaDecoratorEnumerator;
+begin
+  Result := TDiaDecoratorEnumerator.Create(Self);
+end;
+
+{ TDiaDecorator }
+
+constructor TDiaDecorator.Create(AOwner: TDiaDecoratorList);
+begin
+  if AOwner <> nil then
+    AOwner.Add(Self);
+end;
+
 { TDiaLink }
 
 procedure TDiaLink.Draw;
@@ -540,6 +633,17 @@ begin
     c.Changed(ASender);
 end;
 
+constructor TDiaElement.Create;
+begin
+  FDecorators := TDiaDecoratorList.Create(Self);
+end;
+
+destructor TDiaElement.Destroy;
+begin
+  FreeAndNil(FDecorators);
+  inherited;
+end;
+
 procedure TDiaElement.Draw;
 begin
   //
diff --git a/components/tachart/tadiagramdrawing.pas b/components/tachart/tadiagramdrawing.pas
index 44e93516b2..a1bb4b8e35 100644
--- a/components/tachart/tadiagramdrawing.pas
+++ b/components/tachart/tadiagramdrawing.pas
@@ -25,10 +25,19 @@ type
     property Drawer: IChartDrawer read FDrawer write FDrawer;
   end;
 
+  TDiaPenDecorator = class(TDiaDecorator)
+  private
+    FPen: TFPCustomPen;
+  public
+    constructor Create(AOwner: TDiaDecoratorList);
+    destructor Destroy; override;
+    property Pen: TFPCustomPen read FPen;
+  end;
+
 implementation
 
 uses
-  Math, Types,
+  Math, Types, SysUtils,
   TAGeometry;
 
 function ToImage(const AP: TDiaPoint): TPoint; inline;
@@ -62,18 +71,20 @@ var
   Length: Integer = 20;
   startPos, endPos: TPoint;
   AAngle: float;
+  d: TDiaDecorator;
 begin
   if (ASelf.Start = nil) or (ASelf.Finish = nil) then exit;
   id := (ASelf.Owner.Context as TDiaContextDrawer).Drawer;
   id.PrepareSimplePen($000000);
-  if ASelf.Dashes then
-    id.SetPenParams(psDash, $000000);
-  id.SetBrushColor($FFFFFF);
+  for d in ASelf.Decorators do
+    if d is TDiaPenDecorator then
+      id.Pen := (d as TDiaPenDecorator).Pen;
   startPos := ToImage(ASelf.Start.ActualPos);
   endPos := ToImage(ASelf.Finish.ActualPos);
   id.Line(startPos, endPos);
   if not ASelf.Arrow then exit;
   id.SetPenParams(psSolid, $000000);
+  id.SetBrushColor($FFFFFF);
   da := ArcTan2(Width, Length);
 
   endPos := ToImage(ASelf.Finish.ActualPos);
@@ -84,6 +95,21 @@ begin
   id.Polygon([pt1, endPos, pt2], 0, 3);
 end;
 
+{ TDiaPenDecorator }
+
+constructor TDiaPenDecorator.Create(AOwner: TDiaDecoratorList);
+begin
+  inherited Create(AOwner);
+  FPen := TFPCustomPen.Create;
+  FPen.Mode := pmCopy;
+end;
+
+destructor TDiaPenDecorator.Destroy;
+begin
+  FreeAndNil(FPen);
+  inherited;
+end;
+
 initialization
   TDiaBox.FInternalDraw := @DrawDiaBox;
   TDiaLink.FInternalDraw := @DrawDiaLink;