Delphi GDI+ 學習記錄(25): 變換 - Transform

//比例變化

var
　g: TGPGraphics;
　p: TGPPen;
　rect: TGPRect;
begin
　g := TGPGraphics.Create(Canvas.Handle);
　p := TGPPen.Create(MakeColor(255,255,0,0),0);
　rect := MakeRect(10,10,100,100);
　g.DrawRectangle(p, rect); {原始}
　g.ScaleTransform(2, 0.5); {橫向放大、縱向縮小}
　p.SetColor(aclBlue);　　　{變個顏色看清楚}
　g.DrawRectangle(p, rect); {重繪}
　g.ResetTransform;　　　　 {恢復變化, 不然下一個變化將基於現在的狀態}
　p.Free;
　g.Free;
end;

//角度變化(旋轉)

var
　g: TGPGraphics;
　p: TGPPen;
　rect: TGPRect;
begin
　g := TGPGraphics.Create(Canvas.Handle);
　p := TGPPen.Create(MakeColor(255,255,0,0),0);
　rect := MakeRect(10,10,100,100);
　g.DrawRectangle(p, rect);
　g.RotateTransform(28); {旋轉28度角, 正值順時針、負值逆時針}
　p.SetColor(aclBlue);
　g.DrawRectangle(p, rect);
　g.ResetTransform;
　p.Free;
　g.Free;
end;

//位置變化(移動)

var
　g: TGPGraphics;
　p: TGPPen;
　rect: TGPRect;
begin
　g := TGPGraphics.Create(Canvas.Handle);
　p := TGPPen.Create(MakeColor(255,255,0,0),0);
　rect := MakeRect(10,10,100,100);
　g.DrawRectangle(p, rect);
　g.TranslateTransform(111,111); {移動}
　p.SetColor(aclBlue);
　g.DrawRectangle(p, rect);
　g.ResetTransform;
　p.Free;
　g.Free;
end;