PPMG source code

Source code for the Pointless PHP Mandelbrot Generator.

---

$width = 100.0;
$height = 40.0;

if (is_NULL($_GET["t"])) {
  $type = 2;
} else {
  $type=$_GET["t"];
  if ($type < 2 || $type > 4 ) $type = 2;
}

if (is_NULL($_GET["x"]) || 
    is_NULL($_GET["y"]) || 
    is_NULL($_GET["r"]) || 
    is_NULL($_GET["i"])) {
  if ($type == 2) { 
    $range = 2.5; 
    $xCenter = -0.5;
    $yCenter = 0.0;
    $iMax = 64;
  } 
  if ($type == 3) {
    $range = 2.7;
    $xCenter = 0.0;
    $yCenter = 0.0;
    $iMax = 64;
  }
  if ($type == 4) {
    $range = 2.2; 
    $xCenter = -0.25;
    $yCenter = 0.0;
    $iMax = 64;
  }
} else {
  $xCenter = $_GET["x"];
  $yCenter = $_GET["y"];
  $range = $_GET["r"];
  $iMax = $_GET["i"];
}



$newRange = $range*0.6;
$newIMax = $iMax*1.4; 

function inSet($cx, $cy, $maxiter) {
  $a = 0.0;
  $b = 0.0;
  $a2 = 0.0;
  $b2 = 0.0;
  $i = 0;
  do {
    $tmp = $a2 - $b2 + $cx;
    $b = 2.0*$a*$b + $cy;
    $a = $tmp;
    $a2 = $a*$a;
    $b2 = $b*$b;
    $i++;
  } while($a2 + $b2 < 4.0 && $i < $maxiter);
  if ($a2 + $b2 < 4.0) return TRUE;
  return FALSE;
}

function inSetZ3($cx, $cy, $maxiter) {
  $a = 0.0;
  $b = 0.0;
  $a2 = 0.0;
  $b2 = 0.0;
  $i = 0;
  do {
    $tmp = $a*($a2 - 3*$b2) + $cx;
    $b = $b*(3*$a2 - $b2) + $cy;
    $a = $tmp;
    $a2 = $a*$a;
    $b2 = $b*$b;
    $i++;
  } while($a2 + $b2 < 4.0 && $i < $maxiter);
  if ($a2 + $b2 < 4.0) return TRUE;
  return FALSE;
}

function inSetZ4($cx, $cy, $maxiter) {
  $a = 0.0;
  $b = 0.0;
  $a2 = 0.0;
  $b2 = 0.0;
  $i = 0;
  do {
    $tmp = $a2*($a2 - 6*$b2) + $b2*$b2 + $cx;
    $b = 4*$a*$b*($a2 - $b2) + $cy;
    $a = $tmp;
    $a2 = $a*$a;
    $b2 = $b*$b;
    $i++;
  } while($a2 + $b2 < 4.0 && $i < $maxiter);
  if ($a2 + $b2 < 4.0) return TRUE;
  return FALSE;
}


$self=$_SERVER["PHP_SELF"];

$j=0;
while ($j < $height) {
  $y = $yCenter + $range*($j - $height/2.0)/$height;
  $i = 0;                                   
  while ($i < $width) {
    $x = $xCenter + $range*($i - $width/2.0)/$width;
    print("<a href=\"$self?");
    print("x=$x&y=$y&r=$newRange&i=$newIMax&t=$type\">");
    if (($type == 2 && inSet($x, $y, $iMax)) || 
        ($type == 3 && inSetZ3($x, $y, $iMax)) || 
        ($type == 4 && inSetZ4($x, $y, $iMax))) {
      print("*");
    } else {
      print("-");
    }
    print("</a>");
    $i++;
  }
  print("<br>");
  $j++;
}

print("<br><br>");
print("Reset: <a href=\"ppmg.php?t=2\">z = z^2 + c</a>");
print(" <a href=\"ppmg.php?t=3\">z = z^3 + c</a>");
print(" <a href=\"ppmg.php?t=4\">z = z^4 + c</a>");

---