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Hello, I have a website called http://flappycreator.com/ where users can upload multiple images to create their own version of Flappy Bird. As a result of this I created a PHP page that takes a GET param to create a preview image of their game to display in various locations on the website. Here is an example: http://flappycreator.com/preview.php?id=5305a9ad9dc30 http://flappycreator.com/flappy.php?id=5305a9ad9dc30 http://flappycreator.com/share.php?id=5305a9ad9dc30 My issue is, I have given my users the ability to upload PNGs or JPGs and trying to figure out reliable code to display the preview has become a huge hassle. In the example above the Pac-Man character shows a white background but when you play the game, it is actually transparent. In other situations I am getting extremely bad color distortion. The code I have provided is my final attempt after a ton of trial-and-error and the PNG imagealphablending() and imagesavealpha() commands have shown me the best results, however I don't know what they do. Please help! Thanks. <?php $bird_picture = "default/bird.png"; $tube1_picture = "default/tube1.png"; $tube2_picture = "default/tube2.png"; $ground_picture = "default/ground.png"; $bg_picture = "default/bg.png"; // If an id is set, then reset values if (isset ( $_GET ['id'] )) { require ('XXX.php'); $db = new DBAccess (); $query = "SELECT * FROM XXX WHERE XXX = '{$_GET['id']}'"; $result = $db->query ( $query ); $num_results = $result->num_rows; $row = mysqli_fetch_array ( $result ); if ($num_results != 0) { if ($row ['bird_picture'] != "") { $bird_picture = "instances/" . $row ['folder_dir'] . "/" . $row ['bird_picture']; } if ($row ['tube1_picture'] != "") { $tube1_picture = "instances/" .$row ['folder_dir'] . "/" . $row ['tube1_picture']; } if ($row ['tube2_picture'] != "") { $tube2_picture = "instances/" .$row ['folder_dir'] . "/" . $row ['tube2_picture']; } if ($row ['ground_picture'] != "") { $ground_picture = "instances/" . $row ['folder_dir'] . "/" . $row ['ground_picture']; } if ($row ['bg_picture'] != "") { $bg_picture = "instances/" . $row ['folder_dir'] . "/" . $row ['bg_picture']; } } } $temp = explode(".", $bg_picture); $extension = end($temp); if ($extension == "jpeg" || $extension == "jpg") { $background = imagecreatefromjpeg($bg_picture); } else { $background = imagecreatefrompng($bg_picture); // Turn off alpha blending and set alpha flag imagealphablending($background, true); imagesavealpha($background, true); } $temp = explode(".", $ground_picture); $extension = end($temp); if ($extension == "jpeg" || $extension == "jpg") { $ground = imagecreatefromjpeg($ground_picture); } else { $ground = imagecreatefrompng($ground_picture); // Turn off alpha blending and set alpha flag imagealphablending($ground, false); imagesavealpha($ground, true); } $temp = explode(".", $bird_picture); $extension = end($temp); if ($extension == "jpeg" || $extension == "jpg") { $bird = imagecreatefromjpeg($bird_picture); } else { $bird = imagecreatefrompng($bird_picture); // Turn off alpha blending and set alpha flag imagealphablending($bird, false); imagesavealpha($bird, true); } $temp = explode(".", $tube1_picture); $extension = end($temp); if ($extension == "jpeg" || $extension == "jpg") { $tube1 = imagecreatefromjpeg($tube1_picture); } else { $tube1 = imagecreatefrompng($tube1_picture); // Turn off alpha blending and set alpha flag imagealphablending($tube1, false); imagesavealpha($tube1, true); } $temp = explode(".", $tube2_picture); $extension = end($temp); if ($extension == "jpeg" || $extension == "jpg") { $tube2 = imagecreatefromjpeg($tube2_picture); } else { $tube2 = imagecreatefrompng($tube2_picture); // Turn off alpha blending and set alpha flag imagealphablending($tube2, false); imagesavealpha($tube2, true); } imagecopymerge($background, $tube1, 200, -200, 0, 0, 52, 320, 100); imagecopymerge($background, $tube2, 200, 200, 0, 0, 52, 320, 100); imagecopymerge($background, $ground, 0, 320, 0, 0, 336, 112, 100); imagecopymerge($background, $bird, 70, 190, 0, 0, 36, 26, 100); header('Content-Type: image/png'); imagepng($background); # Destroy imagedestroy($background); imagedestroy($ground); imagedestroy($bird); imagedestroy($tube1); imagedestroy($tube2); ?> preview.php