GdiPlus[30]: IGPPen: 线帽

StartCap 和 EndCap 属性分别用来读写两段的线帽, 测试图:

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StartCap 和 EndCap 测试代码:

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uses GdiPlus;



procedure TForm1.FormPaint(Sender: TObject);

const

  CapArr: array[0..8] of Byte = (0, 1, 2, 3, $10, $11, $12, $13, $14);

var

  Graphics: IGPGraphics;

  Pen: IGPPen;

  Pt1,Pt2: TGPPoint;

  i: Integer;

begin

  Pt1.Initialize(20, 20);

  Pt2.Initialize(200, 20);

  Graphics := TGPGraphics.Create(Handle);

  Pen := TGPPen.Create($FF2E8B57, 11);



  for i := 0 to Length(CapArr) - 1 do

  begin

    Pen.StartCap := TGPLineCap(CapArr[i]);

    Pen.EndCap := Pen.StartCap;

    Graphics.DrawLine(Pen, Pt1, Pt2);

    Graphics.TranslateTransform(0, Pt1.Y * 1.5);

  end;

end;


 
   

DashCap 属性用来读写虚线线帽, 这在实线中没有效果; 测试图:

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DashCap 测试代码:

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uses GdiPlus;



procedure TForm1.FormPaint(Sender: TObject);

var

  Graphics: IGPGraphics;

  Pen: IGPPen;

  Pt1,Pt2: TGPPoint;

begin

  Pt1.Initialize(20, 20);

  Pt2.Initialize(240, 20);

  Graphics := TGPGraphics.Create(Handle);

  Pen := TGPPen.Create($FF4169E1, 11);

  Pen.DashStyle := DashStyleDashDot;



  Pen.DashCap := DashCapFlat;

  Graphics.DrawLine(Pen, Pt1, Pt2);

  Graphics.TranslateTransform(0, Pt1.Y * 1.5);



  Pen.DashCap := DashCapRound;

  Graphics.DrawLine(Pen, Pt1, Pt2);

  Graphics.TranslateTransform(0, Pt1.Y * 1.5);



  Pen.DashCap := DashCapTriangle;

  Graphics.DrawLine(Pen, Pt1, Pt2);

end;


 
   

可通过 SetLineCap 方法一起设定 StartCap、EndCap、DashCap, 测试图:

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SetLineCap 测试代码:

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uses GdiPlus;



procedure TForm1.FormPaint(Sender: TObject);

var

  Graphics: IGPGraphics;

  Pen: IGPPen;

begin

  Graphics := TGPGraphics.Create(Handle);

  Pen := TGPPen.Create($FFC71585, 11);

  Pen.DashStyle := DashStyleDashDot;



  Pen.SetLineCap(LineCapRoundAnchor, LineCapArrowAnchor, DashCapTriangle);



  Graphics.DrawLine(Pen, 20, 30, 300, 30);

end;