// Function for making a new resized copy of a file
// mask makes the shortest edge match the mask, so it will be bigger than the mask, always resizes!
// fit makes the longest edge match, always resizes!
// limit makes the image fit, but won't stretch if it's smaller.
function makeImageVersion($newWidth, $newHeight, $filePath, $newName, $fileExtension, $method){
 
        // Find out the original size of the image
        list($wO, $hO) = getimagesize($filePath);
 
        // Get the ratios it would take to resize
        $wR = $newWidth / $wO;
        $hR = $newHeight / $hO;
 
        // Figure out which ratio we need
        switch($method){
                case 'mask':
                        if($wR > $hR){ $ratio = $wR; }
                        else{ $ratio = $hR; }
                        break;
                case 'limit':
                        if($wR < 1 && $wR < $hR){ $ratio = $wR; }
                        elseif($hR < 1){ $ratio = $hR; }
                        else{ $ratio = 1; }
                        break;
                case 'fit':
                default:
                        if($wR > $hR){ $ratio = $hR; }
                        else{ $ratio = $wR; }
                        break;
        }
 
        $wN = round($wO * $ratio);
        $hN = round($hO * $ratio);
 
        $iP = imagecreatetruecolor($wN, $hN);
        imageAlphaBlending($iP, false);
        imageSaveAlpha($iP, true);
 
        if($fileExtension == 'jpg'){ $iI = imagecreatefromjpeg($filePath); }
        elseif($fileExtension == 'png'){        $iI = imagecreatefrompng($filePath); }
        else{ $iI = imagecreatefromgif($filePath); }
 
        imagecopyresampled($iP, $iI, 0, 0, 0, 0, $wN, $hN, $wO, $hO);
 
        if($fileExtension == 'jpg'){ imagejpeg($iP, $newName, 90); }
        elseif($fileExtension == 'png'){ imagepng($iP, $newName); }
        else{ imagegif($iP, $newName); }
}