Page 555 - Beginning PHP 5.3

Chapter 17: Generating Images with PHP

This example creates an array of the polygon ’ s points, called $myPoints . There are six elements in the
array, or three x/y coordinate pairs. This means that there are three corners to this polygon: at (20,20) ,
(185,55) , and (70,80) .
The code then calls the imagepolygon() function, passing it the following parameters:

1. The image resource.
2. The array of points.
3. The number of points in the polygon.

4. The color with which to draw the shape.
Figure 17 - 12 shows the example polygon.

Figure 17-12

By the way, if you want to create filled shapes, you can use functions such as imagefilledrectangle() ,
imagefilledellipse() , imagefilledarc() , and imagefilledpolygon() . Find out more at
http://www.php.net/manual/en/ref.image.php .

Try It Out Draw a Rectangle with Rounded Corners
Now that you know how to draw lines and arcs, you can create a handy function to draw rounded
rectangles. Save the following script as rounded_rectangle.php and open its URL in your browser:
<?php
function roundedRectangle( $image, $x1, $y1, $x2, $y2, $curveDepth, $color )
{
// Draw the four sides
imageline( $image, ($x1 + $curveDepth), $y1, ($x2 - $curveDepth), $y1,
$color );
imageline( $image, ($x1 + $curveDepth), $y2, ($x2 - $curveDepth), $y2,
$color );
imageline( $image, $x1, ($y1 + $curveDepth), $x1, ($y2 - $curveDepth),
$color );
imageline( $image, $x2, ($y1 + $curveDepth), $x2, ($y2 - $curveDepth),
$color );

// Draw the four corners
imagearc( $image, ($x1 + $curveDepth), ($y1 + $curveDepth), (2 *
$curveDepth), (2 * $curveDepth), 180, 270, $color );
imagearc( $image, ($x2 -$curveDepth), ($y1 + $curveDepth), (2 *
$curveDepth), (2 * $curveDepth), 270, 360, $color );

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