再学 GDI+[18] FillEllipse、TGPHatchBrush(阴影画刷)

 

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, TeCanvas, ExtCtrls;

type
  TForm1 = class(TForm)
    ComboBox1: TComboBox;
    ColorBox1: TColorBox;
    ColorBox2: TColorBox;
    procedure FormCreate(Sender: TObject);
    procedure FormPaint(Sender: TObject);
    procedure ColorBox1Change(Sender: TObject);
    procedure ColorBox2Change(Sender: TObject);
    procedure ComboBox1Change(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
uses
  GDIPOBJ,GDIPAPI,TypInfo;
procedure TForm1.ColorBox1Change(Sender: TObject);
begin
  Repaint;
end;

procedure TForm1.ColorBox2Change(Sender: TObject);
begin
  Repaint;
end;

procedure TForm1.ComboBox1Change(Sender: TObject);
begin
  Repaint;
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  i:Integer;
begin
  for I := 0 to Integer(HatchStyleTotal) - 1 do
  begin
    ComboBox1.Items.Add(GetEnumName(TypeInfo(hatchstyle),i));
  end;
  ComboBox1.ItemIndex:=0;
  ColorBox1.ItemIndex:=16;
  ColorBox2.ItemIndex:=3;
  Self.Position:=poDesktopCenter;
end;

procedure TForm1.FormPaint(Sender: TObject);
var
  g:TGPGraphics;
  hb:TGPHatchBrush;
  R:TGPRect;
  fcolor,bcolor:TGPColor;
  hbstype:HatchStyle;
begin
  g:=TGPGraphics.Create(Canvas.Handle);
  g.Clear(aclWhite);
  R:=MakeRect(20,50,ClientWidth - 40,ClientHeight - 70);
  fcolor:=ColorRefToARGB(ColorBox1.Selected);
  bcolor:=ColorRefToARGB(ColorBox2.Selected);
  hbstype:=hatchstyle(ComboBox1.ItemIndex);

  hb:=TGPHatchBrush.Create(hbstype,fcolor,bcolor);
  g.FillEllipse(hb,r);

  hb.Free;
  g.Free;
end;

end.