创建异形窗口[5]

unit Unit1;

interface

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

type
TForm1 = class(TForm)
Button1: TButton;
procedure FormCreate(Sender: TObject);
procedure FormPaint(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure FormDblClick(Sender: TObject);
procedure FormDestroy(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

var
bit: TBitmap;

procedure TForm1.FormCreate(Sender: TObject);
begin
bit := TBitmap.Create;
bit.LoadFromFile('c:\temp\test.bmp');
end;

procedure TForm1.FormPaint(Sender: TObject);
begin
Canvas.Draw(0, 0, bit);
end;

procedure TForm1.Button1Click(Sender: TObject);
var
rgn1,rgn2: HRGN;
x,y,w,h: Integer;
begin
w := bit.Width;
h := bit.Height;

rgn1 := CreateRectRgn(0, 0, w, h);

for x := 0 to w - 1 do
for y := 0 to h - 1 do
if bit.Canvas.Pixels[x,y] = clBlack then
begin
rgn2 := CreateRectRgn(x, y, x+1, y+1);
CombineRgn(rgn1, rgn1, rgn2, RGN_XOR);
DeleteObject(rgn2);
end;
SetWindowRgn(Handle, rgn1, True);

Self.BorderStyle := bsNone;
Self.Width := w;
Self.Height := h;
end;

procedure TForm1.FormDblClick(Sender: TObject);
begin
Close;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
bit.Free;
end;

end.