在delphi中的canvas属性中画图为什么画多了就不显示了呢?
form1.image3.Canvas.Pen.Color:=clblack;
form1.image3.Canvas.Pen.Width:=3;
form1.Image3.Canvas.Brush.Color:=clwhite;
form1.image3.Canvas.Rectangle((34+60*3),22,(85+60*3),94);
form1.image3.Canvas.Rectangle((48+60*3),8,(70+60*3),22);
c2:=round((buffer1[28]*18)/1000);
form1.Image3.Canvas.Pen.Width:=1;
form1.Image3.Canvas.Pen.Color:=clwhite;
form1.Image3.Canvas.Brush.Color:=clgreen;
form1.Image3.Canvas.Rectangle((34+60*3),(94-c2),(85+60*3),94);
大侠们指教呀