Don't Be a Square
By Al Williams
Dr. Dobb's Sourcebook January/February 1997
<b>(a)</b> Canvas.MoveTo(0,0); Canvas.LineTo(100,100); <b>(b)</b> with Form1.Canvas do begin . . . Pen.Width:=22; Pen.Color:=clRed; angle:=((hour+min/60)*30-90)*0.0175; x:=Round(2*(radius/3)* cos(angle))+pt.x; y:=Round(2*(radius/3)* sin(angle))+pt.y; MoveTo(pt.x,pt.y); LineTo(x,y); . . . <b>(c)</b> SetBKMode(Canvas.Handle,TRANSPARENT); SetBKColor(Canvas.Handle,RGB(0,0,0);
Example 2: (a) Drawing a 45 degree line; (b) drawing the hour hand of a clock; (c) using the canvas' Handle property to call the Windows API.