[Shootout-list] OCaml compilation flags, improved Mandelbrot

[Brent Fulgham]

Applied, thanks.

On Mar 17, 2005, at 4:08 PM, Christophe TROESTLER wrote:

> let niter = 50
> let limit = 2.
>
> let limit2 = limit *. limit
>
> type complex = { mutable r:float; mutable i:float }
>
> let add_bit0 ~tmp:z c byte =
>   z.r <- 0.;
>   z.i <- 0.;
>   try
>     for i = 1 to niter do
>       let zi = 2. *. z.r *. z.i +. c.i in
>       z.r <- z.r *. z.r -. z.i *. z.i +. c.r;
>       z.i <- zi;
>       if z.r *. z.r +. z.i *. z.i > limit2 then raise Exit;
>     done;
>     (byte lsl 1) lor 0x01
>   with Exit -> (byte lsl 1) lor 0x00
>
> let () =
>   let w = int_of_string Sys.argv.(1) in
>   let h = w in
>   let fw = float w
>   and fh = float h
>   and cplmt8 = 8 - w mod 8 in
>   Printf.printf "P4\n%i %i\n" w h;
>   let byte = ref 0
>   and bit = ref 0 in
>   let c = { r = 0.0; i = 0.0 } in
>   let tmp = { r = 0.0; i = 0.0 } in
>   for y = 0 to h - 1 do
>     c.i <- 2. *. float y /. fh -. 1.;
>     for x = 0 to w - 1 do
>       c.r <- 2. *. float x /. fw -. 1.5;
>       byte := add_bit0 ~tmp c !byte;
>       incr bit;
>       if !bit = 8 then (
>         output_byte stdout !byte;
>         byte := 0;
>         bit := 0;
>       )
>     done;
>     if !bit <> 0 then (
>       output_byte stdout (!byte lsl cplmt8);
>       byte := 0;
>       bit := 0;
>     )
>   done