| /* |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions are met: |
| |
| * Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| |
| * Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| |
| * Neither the name of "The Computer Language Benchmarks Game" nor the |
| name of "The Computer Language Shootout Benchmarks" nor the names of |
| its contributors may be used to endorse or promote products derived |
| from this software without specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /* The Computer Language Benchmarks Game |
| * http://shootout.alioth.debian.org/ |
| * |
| * contributed by The Go Authors. |
| * Based on mandelbrot.c contributed by Greg Buchholz |
| */ |
| |
| package main |
| |
| import ( |
| "bufio"; |
| "flag"; |
| "fmt"; |
| "os"; |
| ) |
| |
| var n = flag.Int("n", 200, "size") |
| |
| func main() { |
| flag.Parse(); |
| out := bufio.NewWriter(os.Stdout); |
| defer out.Flush(); |
| |
| w := *n; |
| h := *n; |
| bit_num := 0; |
| byte_acc := byte(0); |
| const Iter = 50; |
| const Zero float64 = 0; |
| const Limit = 2.0; |
| |
| fmt.Fprintf(out, "P4\n%d %d\n", w, h); |
| |
| for y := 0; y < h; y++ { |
| for x := 0; x<w; x++ { |
| Zr, Zi, Tr, Ti := Zero, Zero, Zero, Zero; |
| Cr := (2*float64(x)/float64(w) - 1.5); |
| Ci := (2*float64(y)/float64(h) - 1.0); |
| |
| for i := 0; i < Iter && (Tr+Ti <= Limit*Limit); i++ { |
| Zi = 2*Zr*Zi + Ci; |
| Zr = Tr - Ti + Cr; |
| Tr = Zr * Zr; |
| Ti = Zi * Zi; |
| } |
| |
| byte_acc <<= 1; |
| if Tr+Ti <= Limit*Limit { |
| byte_acc |= 0x01; |
| } |
| |
| bit_num++; |
| |
| if bit_num == 8 { |
| out.WriteByte(byte_acc); |
| byte_acc = 0; |
| bit_num = 0; |
| } else if x == w-1 { |
| byte_acc <<= uint(8-w%8); |
| out.WriteByte(byte_acc); |
| byte_acc = 0; |
| bit_num = 0; |
| } |
| } |
| } |
| } |