imagepolygonDescriptionThis can be a difficult function to understand and use. The array specifying the drawing coordinates must contain both the x and y coordinates of each point in the polygon. For example, array(100,100,125,125,150,150,200,200,100,100) indicates that the first point is at (100,100), the second at (125,125), and so on. The polygon must have at least three vertices for the function to work; a good way to determine the number of vertices is to count the array using count() and divide by two. A point is made up of two values. If you used user input to assign the polygon points, you can use the modulus operator (%) to determine whether an even number of values were given. ExampleExample 431. Create an unfilled red polygon header("Content-type: image/png"); $im = imagecreate(200, 200); $green = imagecolorallocate($im, 0, 255, 0); $red = imagecolorallocate($im, 255, 0, 0); $points = array(100, 10, 150, 50, 160, 80, 10, 150, 100, 10); $vertices = count($points) / 2; imagepolygon($im, $points, $vertices, $red); imagepng($im); imagedestroy($im);
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
This material may be distributed only subject to the terms and conditions set forth
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