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/* The Computer Language Benchmarks Game
http://shootout.alioth.debian.org/
contributed by Stefan Krause
slightly modified by Chad Whipkey
*/
import java.io.IOException;
import java.io.PrintStream;
class mandelbrot {
public static void main(String[] args) throws Exception {
new Mandelbrot(Integer.parseInt(args[0])).compute();
}
public static class Mandelbrot {
private static final int BUFFER_SIZE = 8192;
public Mandelbrot(int size) {
this.size = size;
fac = 2.0 / size;
out = System.out;
shift = size % 8 == 0 ? 0 : (8- size % 8);
}
final int size;
final PrintStream out;
final byte [] buf = new byte[BUFFER_SIZE];
int bufLen = 0;
final double fac;
final int shift;
public void compute() throws IOException
{
out.format("P4\n%d %d\n",size,size);
for (int y = 0; y<size; y++)
computeRow(y);
out.write( buf, 0, bufLen);
out.close();
}
private void computeRow(int y) throws IOException
{
int bits = 0;
final double Ci = (y*fac - 1.0);
final byte[] bufLocal = buf;
for (int x = 0; x<size;x++) {
double Zr = 0.0;
double Zi = 0.0;
double Cr = (x*fac - 1.5);
int i = 50;
double ZrN = 0;
double ZiN = 0;
do {
Zi = 2.0 * Zr * Zi + Ci;
Zr = ZrN - ZiN + Cr;
ZiN = Zi * Zi;
ZrN = Zr * Zr;
} while (!(ZiN + ZrN > 4.0) && --i > 0);
bits = bits << 1;
if (i == 0) bits++;
if (x%8 == 7) {
bufLocal[bufLen++] = (byte) bits;
if ( bufLen == BUFFER_SIZE) {
out.write(bufLocal, 0, BUFFER_SIZE);
bufLen = 0;
}
bits = 0;
}
}
if (shift!=0) {
bits = bits << shift;
bufLocal[bufLen++] = (byte) bits;
if ( bufLen == BUFFER_SIZE) {
out.write(bufLocal, 0, BUFFER_SIZE);
bufLen = 0;
}
}
}
}
}
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