[Aidan]

I made a few modifications to the code, as it's not really suitable for later versions of vBulletin 3.0.x. I made some alterations to support 3.0.6, as I'm trying to migrate a bunch of hacks across as part of an upgrade.

First of all, there's some code that spits out the content-length to tell the browser how large the file is. With current hack, the code spits out one content-length, and then an image with a different length. Some browsers get confused with this.

So, firstly, back up file you're going to edit!! This has been tested on a single forum, so it might well BREAK your forum if you try it.

Then, find the line that states (near the bottom)

header('Content-Length: ' . $attachmentinfo['filesize']);

and remove it. We'll replace it in another position later.

Once again, find the lines that state

        echo $attachmentinfo['filedata'];

And change them to be like the following

if ($extension == 'jpg' && !$thumb) {
        $filename = "path/to/the/file/vB3/watermark.png"; // use a PNG-24 to preserve transparency!

        $im = imagecreatefromstring($attachmentinfo['filedata']);
        imagealphablending($im, true);

        $watermark = imagecreatefrompng($filename);

        $y = imagesy($im) - imagesy($watermark); // select the bottom left (y of im less y of watermark)
        // if you want top left, you could use $y=0; instead
        
        $w = imagesx($watermark);
        $h = imagesy($watermark);
        
        imagecopy($im, $watermark, 0, $y, 0, 0, $w, $h);

        imagejpeg($im, "", 80);

        imagedestroy($watermark); // clean up after ourselves!
        imagedestroy($im);
        } else {

        header('Content-Length: ' . $attachmentinfo['filesize']);
        echo $attachmentinfo['filedata'];
}

Now, for some reason, I've got one or two images it doesn't seem to work right on. I have no idea why, and I'm hoping someone else might be able to give a hint or two? Also what would be good would be the ability to generate the appropriate content-length header, but again, I've no clue how to do that.

Hopefully Robbban will be able to incorporate some of these changes into an "offical" version - after all, it is his code!