PHP | imagepolygon() Function

Last Updated : 15 Dec, 2022

The imagepolygon() function is an inbuilt function in PHP which is used to draw a polygon. This function returns TRUE on success and returns FALSE otherwise.
Syntax:

bool imagepolygon( $image, $points, $num_points, $color )

Parameters: This function accepts four parameters as mentioned above and described below:

$image: The imagecreatetruecolor() function is used to create a blank image in a given size.
$points: This parameter is used to hold the consecutive vertices of polygon.
$num_points: This parameter contains total number of vertices in a polygon. It must be greater than 3, because minimum three vertices required to create a polygon.
$color: This variable contains the filled color identifier. A color identifier created with imagecolorallocate() function.

Return Value: This function returns TRUE on success or FALSE on failure.
Below programs illustrate the imagepolygon() function in PHP.
Program 1:

php

<?php
  
// Set the vertices of polygon
$values = array(
            150,  50, // Point 1 (x, y)
            50, 250,  // Point 2 (x, y)
            250,  250 // Point 3 (x, y)
        );
    
// Create the size of image or blank image
$image = imagecreatetruecolor(300, 300);
  
// Set the background color of image
$background_color = imagecolorallocate($image,  0, 153, 0);
   
// Fill background with above selected color
imagefill($image, 0, 0, $background_color);
 
// Allocate a color for the polygon
$image_color = imagecolorallocate($image, 255, 255, 255);
   
// Draw the polygon
imagepolygon($image, $values, 3, $image_color);
   
// Output the picture to the browser
header('Content-type: image/png');
   
imagepng($image);
?>

Output:

img polygon

Program 2:

php

<?php
  
// Set the vertices of polygon
$values = array(
            150, 50, // Point 1 (x, y)
            55, 119, // Point 2 (x, y)
            91, 231, // Point 3 (x, y)
            209, 231, // Point 4 (x, y)
            245, 119  // Point 5 (x, y)
            );
 
// Create the size of image or blank image
$image = imagecreatetruecolor(300, 300);
  
// Set the background color of image
$background_color = imagecolorallocate($image,  0, 153, 0);
   
// Fill background with above selected color
imagefill($image, 0, 0, $background_color);
 
// Allocate a color for the polygon
$col_poly = imagecolorallocate($image, 255, 255, 255);
  
// Draw the polygon
imagepolygon($image, $values, 5, $col_poly);
  
// Output the picture to the browser
header('Content-type: image/png');
  
imagepng($image);
?>