再学 GDI+[78]: 区域(7) - Translate - 区域的平移变换

unit Unit1;

interface

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

type
TForm1 = class(TForm)
TrackBar1: TTrackBar;
TrackBar2: TTrackBar;
procedure FormPaint(Sender: TObject);
procedure FormCreate(Sender: TObject);
procedure TrackBar1Change(Sender: TObject);
procedure TrackBar2Change(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

uses GDIPOBJ, GDIPAPI;

procedure TForm1.FormCreate(Sender: TObject);
begin
TrackBar1.Min := -ClientWidth div 2;
TrackBar1.Max := ClientWidth div 2;
TrackBar2.Min := -ClientHeight div 2;
TrackBar2.Max := ClientHeight div 2;

DoubleBuffered := True;
end;

procedure TForm1.FormPaint(Sender: TObject);
var
g: TGPGraphics;
b: TGPBrush;
rgn: TGPRegion;
begin
g := TGPGraphics.Create(Canvas.Handle);
b := TGPHatchBrush.Create(HatchStyleShingle, aclSilver, aclDarkCyan);
rgn := TGPRegion.Create(MakeRect(40, 40, ClientWidth-100, ClientHeight-100));

rgn.Translate(TrackBar1.Position, TrackBar2.Position);

g.FillRegion(b, rgn);

rgn.Free;
b.Free;
g.Free;
end;

procedure TForm1.TrackBar1Change(Sender: TObject);
begin
Repaint;
end;

procedure TForm1.TrackBar2Change(Sender: TObject);
begin
Repaint;
end;

end.

object Form1: TForm1
Left = 0
Top = 0
Caption = 'Form1'
ClientHeight = 174
ClientWidth = 219
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 TrackBar1: TTrackBar
Left = 0
Top = 151
Width = 217
Height = 23
ShowSelRange = False
TabOrder = 1
OnChange = TrackBar1Change
end
object TrackBar2: TTrackBar
Left = 196
Top = 0
Width = 23
Height = 166
Orientation = trVertical
ShowSelRange = False
TabOrder = 0
OnChange = TrackBar2Change
end
end