найдите ошибку, буду признателен!

function TBatF.cx(x,y:integer):integer;
var
shag:real;
begin
shag:=98/Sqrt(Sqr(98)+Sqr(490));//~0.196
result:=round(y*shag+x/(1+y/980));
end;
function TBatF.cy(y:integer):integer;
begin
result:=round(y-(0.05*y));
end;
procedure TBatF.Button1Click(Sender: TObject);
var
blineX,blineY,elineX,elineY:integer;
begin
for blineY:=0 to 10 do
begin
for blineX:=0 to 12 do
begin
pole.Canvas.MoveTo(cx(blineX*49,0),490);
pole.Canvas.LineTo(cx(blineX*49,490),0);
end;
pole.Canvas.MoveTo(cx(0,(10-blineY)*49),blineY*49);
pole.Canvas.LineTo(cx(588,(10-blineY)*49),blineY*49);//<-это неправильно
end;
end;