//畫弧線
var
g: TGPGraphics;
p: TGPPen;
begin
g := TGPGraphics.Create(Canvas.Handle);
p := TGPPen.Create(MakeColor(255,0,0),2);
g.DrawArc(p,11,32,300,200,0,90); {參數 2-5 是一個橢圓}
p.SetColor(MakeColor(0,255,0));
g.DrawArc(p,11,32,300,200,90,90); {參數 6 是弧線起點度數, 從右中開始}
p.SetColor(MakeColor(0,0,255));
g.DrawArc(p,11,32,300,200,180,90); {參數 7 是弧線終點, 是從起點到終點的弧度}
p.SetColor(MakeColor(255,255,0));
g.DrawArc(p,11,32,300,200,270,90); {現在剛好繞成一個圓}
p.SetColor(MakeColor(0,0,0));
g.DrawArc(p,88,88,200,100,0,360); {如果從 0 度開始延伸 360 度, 就是畫橢圓線了}
p.Free;
g.Free;
end;