Data commit

Task/Mandelbrot-set/C3/mandelbrot-set.c3

@@ -0,0 +1,58 @@
+module mandelbrot;
+
+extern fn int atoi(char *s);
+extern fn int printf(char *s, ...);
+extern fn void putchar(int c);
+
+fn void main(int argc, char **argv)
+{
+  int w = atoi(argv[1]);
+  int h = w;
+
+  const LIMIT = 2.0;
+  const SQUARE_LIMIT = LIMIT * LIMIT;
+
+  printf("P4\n%d %d\n", w, h);
+
+  int iter = 50;
+  int bit_num = 0;
+  char byte_acc = 0;
+  for (double y = 0; y < h; y++)
+  {
+    for (double x = 0; x < w; x++)
+    {
+      double zr;
+      double zi;
+      double ti;
+      double tr;
+      double cr = (2.0 * x / w - 1.5);
+      double ci = (2.0 * y / h - 1.0);
+      for (int i = 0; i < iter && (tr + ti <= SQUARE_LIMIT); i++)
+      {
+        zi = 2.0 * zr * zi + ci;
+        zr = tr - ti + cr;
+        tr = zr * zr;
+        ti = zi * zi;
+      }
+
+      byte_acc <<= 1;
+      if (tr + ti <= SQUARE_LIMIT) byte_acc |= 0x01;
+
+      ++bit_num;
+
+      if (bit_num == 8)
+      {
+        putchar(byte_acc);
+        byte_acc = 0;
+        bit_num = 0;
+      }
+      else if (x == w - 1)
+      {
+        byte_acc <<= (8 - w % 8);
+        putchar(byte_acc);
+        byte_acc = 0;
+        bit_num = 0;
+      }
+    }
+  }
+}