再学 GDI+[53]: 路径 - SetFillMode

本例效果图:

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代码文件:

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unit Unit1;



interface



uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls, ExtCtrls;



type

  TForm1 = class(TForm)

    RadioGroup1: TRadioGroup;

    procedure FormCreate(Sender: TObject);

    procedure FormPaint(Sender: TObject);

    procedure RadioGroup1Click(Sender: TObject);

  end;



var

  Form1: TForm1;



implementation



{$R *.dfm}



uses GDIPOBJ, GDIPAPI, TypInfo;



procedure TForm1.FormCreate(Sender: TObject);

var

  i: Integer;

begin

  RadioGroup1.Columns := 2;

  RadioGroup1.Caption := '路径填充模式';

  for i := 0 to 1 do

    RadioGroup1.Items.Add(GetEnumName(TypeInfo(TFillMode), i));

  RadioGroup1.ItemIndex := 0;

end;



procedure TForm1.FormPaint(Sender: TObject);

var

  g: TGPGraphics;

  b: TGPBrush;

  p: TGPPen;

  path: TGPGraphicsPath;

  rect: TRect;

begin

  g := TGPGraphics.Create(Canvas.Handle);

  b := TGPHatchBrush.Create(HatchStyleCross, aclSilver, aclKhaki);

  p := TGPPen.Create(aclRed, 1.75);



  path := TGPGraphicsPath.Create;

  rect := Bounds(10, 20, 150, 100);

  path.AddEllipse(MakeRect(rect));

  OffsetRect(rect, 60, 0);

  path.AddEllipse(MakeRect(rect));



  if RadioGroup1.ItemIndex = 1 then path.SetFillMode(FillModeWinding);



  g.FillPath(b, path);

  g.DrawPath(p, path);



  p.Free;

  b.Free;

  path.Free;

  g.Free;

end;



procedure TForm1.RadioGroup1Click(Sender: TObject);

begin

  Repaint;

end;



end.


 
   

窗体文件:

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object Form1: TForm1

  Left = 0

  Top = 0

  Caption = 'Form1'

  ClientHeight = 184

  ClientWidth = 233

  Color = clBtnFace

  Font.Charset = DEFAULT_CHARSET

  Font.Color = clWindowText

  Font.Height = -11

  Font.Name = 'Tahoma'

  Font.Style = []

  OldCreateOrder = False

  Position = poDesktopCenter

  OnCreate = FormCreate

  OnPaint = FormPaint

  PixelsPerInch = 96

  TextHeight = 13

  object RadioGroup1: TRadioGroup

    Left = 5

    Top = 137

    Width = 224

    Height = 39

    Caption = 'RadioGroup1'

    TabOrder = 0

    OnClick = RadioGroup1Click

  end

end