我在学习GPS编程时写的DELPHI源码 ,比较简单.希望大虾不要见笑.多多指教.

procedure TfrmMain.DrawSatInfo(gps: TGPSInfo; pbx: TPaintBox); var   i: integer;   r: integer;   dx,dy: integer; begin   r := pbx.Width div 2;   for i:= 1 to 12 do begin     if gps.SatInfo[i].PRN 0 then begin       dx := r + Round(r*(90-gps.SatInfo[i].EL)*sin((gps.SatInfo[i].AZ - 90)*Pi/180)/90);       dy := r + Round(r*(90-gps.SatInfo[i].EL)*cos((gps.SatInfo[i].AZ - 90)*Pi/180)/90);       dx := dx - 8;       if dx < 0 then dx := 0;       if gps.SatInfo[i].SN > 20 then begin         pbx.Canvas.Font.Color := clBlue;         pbx.Canvas.TextOut(dx,dy,inttostr(gps.SatInfo[i].PRN));       end else begin