Draw Line Scanline Method

procedure TForm1.BitBtn3Click(Sender: TObject);
//scanline line drawing
type PDW = ^DWORD;
var i : integer;
k : byte;
p,pbase : PDW;
begin
clearBM;
t1 := gettickCount;
for i := 1 to 10000 do
for k := 0 to 99 do
begin
pbase := bm.scanline[k];
p := PDW(DWORD(pbase) + (k shl 2));
p^ := $ff00ff;
end;
t2 := gettickcount;
showtime(1000000);
end;