Delphi GDI+ 學習記錄(29): 區域 - Region

//創建並填充區域

var
　g: TGPGraphics;
　sb: TGPSolidBrush;
　region: TGPRegion;　{定義區域}
begin
　g := TGPGraphics.Create(Canvas.Handle);
　sb := TGPSolidBrush.Create(aclGold);
　region := TGPRegion.Create(MakeRect(50, 50, 150, 150));　{建立區域}
　g.FillRegion(sb, region);　{填充區域}
　sb.Free;
　region.Free;
　g.Free;
end;

//根據路徑建立區域

var
　g: TGPGraphics;
　path: TGPGraphicsPath;
　region: TGPRegion;
　sb: TGPSolidBrush;
const
　pts: array[0..3] of TGPPoint =
　　((x:10 ; y:10 ),
　　 (x:150; y:10 ),
　　 (x:100; y:75 ),
　　 (x:100; y:150));
begin
　g := TGPGraphics.Create(Canvas.Handle);
　sb := TGPSolidBrush.Create(aclRed);
　path := TGPGraphicsPath.Create;
　path.AddPolygon(PGPPoint(@pts), Length(pts));
　region := TGPRegion.Create(path);　{根據路徑建立區域}
　g.FillRegion(sb, region);
　g.Free;
　path.Free;
　region.Free;
　sb.Free;
end;

//區域聯合

var
　g : TGPGraphics;
　sb: TGPSolidBrush;
　region: TGPRegion;
begin
　g := TGPGraphics.Create(Canvas.Handle);
　sb := TGPSolidBrush.Create(aclYellowGreen);
　region := TGPRegion.Create(MakeRect(50, 0, 50, 150));　{建立區域}
　region.Union(MakeRect(0, 50, 150, 50));　{區域聯合}
　g.FillRegion(sb, region);　{填充}
　sb.Free;
　region.Free;
　g.Free;
end;

//用區域剪切畫板

var
　g : TGPGraphics;
　sb: TGPSolidBrush;
　p: TGPPen;
　region: TGPRegion;
　font: TGPFont;
begin
　g := TGPGraphics.Create(Canvas.Handle);
　sb := TGPSolidBrush.Create(aclYellowGreen);
　p := TGPPen.Create(aclRed);
　font := TGPFont.Create('宋體',12);
　region := TGPRegion.Create(MakeRect(50, 0, 50, 150));　{建立區域}
　region.Union(MakeRect(0, 50, 150, 50));　{區域聯合}
　g.FillRegion(sb, region);
　g.SetClip(region);　{用區域剪切畫板}
　g.DrawLine(p, 0, 0, 100, 100);　{測試畫板剪切後的直線}
　sb.SetColor(aclBlack);
　g.DrawString('萬一萬一萬一', -1, font, MakePoint(20.0,20.0), sb);　{測試文本}
　sb.Free;
　p.Free;
　region.Free;
　font.Free;
　g.Free;
end;