3D Captcha

$capthca = new Capthca3d(); 
 
$capthca->render(); 
 
 
 
 
 
class Capthca3d{ 
 
const CHARS = 'WEafRTYIPAGHJKXBNM3479j'; 
 
protected $hypot = 8; 
 
protected $image = null; 
 
 
 
protected $text = ''; 
 
 
 
public function __construct() 
 
{ 
 
$this->time = microtime(true); 
 
$this->generateCode(); 
 
 
 
} 
 
protected function generateCode() 
 
{ 
 
$chars = self::CHARS; 
 
for($i =0; $i<3; $i++){ 
 
$this->text .= $chars{ mt_rand(0,22)}; 
 
} 
 
} 
 
 
 
public function getText() 
 
{ 
 
return $this->text; 
 
} 
 
protected function getProection($x1,$y1,$z1) 
 
{ 
 
$x = $x1 * $this->hypot; 
 
$y = $z1 * $this->hypot; 
 
$z = -$y1 * $this->hypot; 
 
 
 
$xx = 0.707106781187; 
 
$xy = 0; 
 
$xz = -0.707106781187; 
 
 
 
$yx = 0.408248290464; 
 
$yy = 0.816496580928; 
 
$yz = 0.408248290464; 
 
 
 
$cx = $xx*$x + $xy*$y + $xz*$z; 
 
$cy = $yx*$x + $yy*$y + $yz*$z+ 20 * $this->hypot; 
 
return array( 
 
'x' => $cx, 
 
'y' => $cy 
 
); 
 
} 
 
 
 
function zFunction($x,$y){ 
 
$z = imagecolorat($this->image,$y/2,$x/2)>0?2.6:0; 
 
if( $z != 0 ){ 
 
$z += mt_rand(0,60)/100; 
 
} 
 
$z += 1.4 * sin(($x+$this->startX)*3.141592654/15)*sin(($y+$this->startY)*3.141592654/15); 
 
return $z; 
 
} 
 
public function render() 
 
{ 
 
$xx =30; 
 
$yy =60; 
 
 
 
$this->image = imageCreateTrueColor($yy * $this->hypot , $xx * $this->hypot); 
 
 
 
$whiteColor = imageColorAllocate($this->image,255,255,255); 
 
imageFilledRectangle($this->image,0,0,$yy * $this->hypot , $xx * $this->hypot,$whiteColor); 
 
 
 
$textColor = imageColorAllocate($this->image,0,0,0); 
 
imageString($this->image, 5, 3, 0, $this->text, $textColor); 
 
 
 
 
 
$this->startX = mt_rand(0,$xx); 
 
$this->startY = mt_rand(0,$yy); 
 
 
 
$coordinates = array(); 
 
 
 
for($x = 0; $x < $xx + 1; $x++){ 
 
for($y = 0; $y < $yy + 1; $y++){ 
 
$coordinates[$x][$y] = $this->getProection($x,$y,$this->zFunction($x,$y)); 
 
} 
 
} 
 
 
 
for($x = 0; $x < $xx; $x++){ 
 
for($y = 0; $y < $yy; $y++){ 
 
$coord = array(); 
 
$coord[] = $coordinates[$x][$y]['x']; 
 
$coord[] = $coordinates[$x][$y]['y']; 
 
 
 
$coord[] = $coordinates[$x+1][$y]['x']; 
 
$coord[] = $coordinates[$x+1][$y]['y']; 
 
 
 
$coord[] = $coordinates[$x+1][$y+1]['x']; 
 
$coord[] = $coordinates[$x+1][$y+1]['y']; 
 
 
 
$coord[] = $coordinates[$x][$y+1]['x']; 
 
$coord[] = $coordinates[$x][$y+1]['y']; 
 
 
 
$c = (int) ($this->zFunction($x,$y)*32); 
 
$linesColor = imageColorAllocate($this->image, $c, $c, $c); 
 
imageFilledPolygon($this->image, $coord, 4, $whiteColor); 
 
imagePolygon($this->image, $coord, 4, $linesColor); 
 
} 
 
} 
 
 
 
$textColor = imageColorAllocate($this->image,0,0,0); 
 
imageString($this->image, 5, 3, 0, $this->text, $whiteColor); 
 
imageString($this->image, 1, 3, 0, (microtime(true)-$this->time), $textColor); 
 
header('Content-Type: image/png'); 
 
 
 
imagepng($this->image); 
 
imagedestroy($this->image); 
 
} 
 
}