Example: Alpha

02-alpha.php

<?php

/**
 * Imagegradientrectangle Example (Alpha)
 *
 * Copyright (c) 2018-2026 Andrew G. Johnson <andrew@andrewgjohnson.com>
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
 * documentation files (the "Software"), to deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to the following conditions:
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
 * Software.
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
 * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * PHP version 5
 *
 * @category  Andrewgjohnson
 * @package   Imagegradientrectangle
 * @author    Andrew G. Johnson <andrew@andrewgjohnson.com>
 * @copyright 2018-2026 Andrew G. Johnson <andrew@andrewgjohnson.com>
 * @license   https://opensource.org/licenses/mit/ The MIT License
 * @link      https://github.com/andrewgjohnson/imagegradientrectangle
 */

// Include the imagegradientrectangle (and its dependencies’) source if you’re not using Composer
if (
    file_exists('../source/imagegradientrectangle.php')
    && file_exists('dependencies/imageblendedcolorallocate.php')
) {
    require_once '../source/imagegradientrectangle.php';
    require_once 'dependencies/imageblendedcolorallocate.php';
} elseif (!function_exists('imagegradientrectangle')) {
    die('imagegradientrectangle not found');
} elseif (!function_exists('imageblendedcolorallocate')) {
    die('imageblendedcolorallocate not found');
}

// set the parameters for our image
$width            = 600;
$height           = 300;
$offset           = round($width / 10);
$rectangleWidth   = $offset * 2;
$rectangleHeight  = $height - ($offset * 2);

// Create our image
$im               = imagecreatetruecolor($width, $height);

// Set our image’s colors
$backgroundColor  = imagecolorallocate($im, 0xEE, 0xEE, 0xEE);
$greenOpaque      = imagecolorallocate($im, 0x00, 0xFF, 0x00);
$greenTranslucent = imagecolorallocatealpha($im, 0x00, 0xFF, 0x00, 100);

// Fill our image with the background color
imagefill($im, 0, 0, $backgroundColor);

// Fill our image with both colors and then a gradient from one to the other
imagefilledrectangle(
    $im,
    $offset,
    $offset,
    $offset + $rectangleWidth,
    $offset + $rectangleHeight,
    $greenOpaque
);

imagefilledrectangle(
    $im,
    ($offset * 2) + $rectangleWidth,
    $offset,
    ($offset + $rectangleWidth) * 2,
    $offset + $rectangleHeight,
    $greenTranslucent
);

imagegradientrectangle(
    $im,
    ($offset * 3) + ($rectangleWidth * 2),
    $offset,
    ($offset + $rectangleWidth) * 3,
    $offset + $rectangleHeight,
    $greenOpaque,
    $greenTranslucent
);

// Display our image and destroy the GD resource
header('Content-Type: image/png');
imagepng($im);
version_compare(PHP_VERSION, '8.0.0', '<') && imagedestroy($im);

Expected Output

02-alpha.png