(PHP 4, PHP 5, PHP 7)
imagepolygon — Draws a polygon
$image
   , array $points
   , int $num_points
   , int $color
   )
   imagepolygon() creates a polygon in the given
   image.
  
imageAn image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
pointsAn array containing the polygon's vertices, e.g.:
| points[0] | = x0 | 
| points[1] | = y0 | 
| points[2] | = x1 | 
| points[3] | = y1 | 
num_pointsTotal number of points (vertices).
colorA color identifier created with imagecolorallocate().
   Returns TRUE on success or FALSE on failure.
  
Example #1 imagepolygon() example
<?php
// Create a blank image
$image = imagecreatetruecolor(400, 300);
// Allocate a color for the polygon
$col_poly = imagecolorallocate($image, 255, 255, 255);
// Draw the polygon
imagepolygon($image, array(
        0,   0,
        100, 200,
        300, 200
    ),
    3,
    $col_poly);
// Output the picture to the browser
header('Content-type: image/png');
imagepng($image);
imagedestroy($image);
?>
The above example will output something similar to:
