By sinfield on

I am a bit of a PHP dabbler/beginner, and I am trying to write a script to watermark uploaded images. The watermark is variable, based on information supplied by the logged-in user.

What I need now should be relatively easy, assuming displayed images (or their paths) are stored in a variable that I can call. Or is there an easier way?


 global $user;
 $name = $user->name;
 $uid = $user->uid;
 $filename = $name;

// first name query and variable
 $fquery = "SELECT value FROM profile_values WHERE uid='$user->uid' AND fid='3'";
 $result = mysql_query($fquery);

 while ($row = mysql_fetch_object($result)) {
    $fname = "$row->value";
 }

// last name query and variable
 $lquery = "SELECT value FROM profile_values WHERE uid='$user->uid' AND fid='4'";
 $result = mysql_query($lquery);

 while ($row = mysql_fetch_object($result)) {
    $lname = "$row->value";
 }

// concatenate the full name
 $fullname = $fname . " " . $lname;

// create an image with width 'x', height 'y'
 $image = imagecreate(200, 20);

// create a background color and then set it to transparent
 $background = imagecolorallocate($image, 255, 255, 255);
 ImageColorTransparent($image, $background);
 ImageInterlace($image, false);

// set black color for the text
 $black = imagecolorallocate($image, 0, 0, 0);

// write the variable string to the image
// the top left of the text is at the position (10, 2)
 imagestring($image, 4, 10, 2, $fullname, $black);

// output the image as a png
 imagepng($image, "tmp/" . $filename . ".png");
 print ("<img src=\"tmp/" . $filename . ".png\">");

// create the watermark image
 $watermark = imagecreatefrompng("tmp/" . $filename . ".png");

// calculate the watermark dimensions
 $watermark_width = imagesx($watermark);
 $watermark_height = imagesy($watermark);
 $image = imagecreatetruecolor($watermark_width, $watermark_height);
 $image = imagecreatefromjpeg($_GET[$need_variable_source]);

// calculate source image  size
 $size = getimagesize($_GET[$need_variable_source]);

// position the watermark on the source image
 $dest_x = $size[0] - $watermark_width - 5;
 $dest_y = $size[1] - $watermark_height - 5;

// put them together 
 imagecopymerge($image, $watermark, $dest_x, $dest_y, 0, 0, $watermark_width, $watermark_height, 100);
 imagejpeg($image);

 print ("<img src=\"files/images/" . $image . ".png\">");

// cleanup
 imagedestroy($image);
 imagedestroy($watermark);

Right now, it all works fine up to the imagecopymerge and imagejpeg functions if I set a static image source. I need variable source, and I need the script ... well, I need it to work. :-)

I appreciate any help I can get.

⋅ Categories: Drupal 4.6.x

Comments

sinfield’s picture

sinfield commented

Ok, I found the 'files' table in the database, which apparently stores uploaded file locations and the nodes with which they are associated. I guess it is time for me to try to put together another query.

Sorry for the mess above.

Anyone have a quick query to get the active node's image file location and store it to a variable?
I have this, but do not know how to pull the current node:

// fileloc query
 $filequery = "SELECT filepath FROM files WHERE nid='$current_node' AND filename='preview'";
 $result = mysql_query($filequery);

 while ($row = mysql_fetch_object($result)) {
    $fileloc = "$row->filepath";
 }
 
// echo $fileloc;
nedjo’s picture

nedjo
he/him/his
Primary language English
commented

See the documentation http://drupaldocs.org/api/head/function/hook_nodeapi

In a _nodeapi hook you have access to the $node object.

See also the various _nodeapi functions in the core Drupal modules.

I guess you'd use the 'insert' (or 'update') ops.

It's also a good idea to use Drupal's database abstraction calls (e.g., db_query instead of mysql_query, db_fetch_object rather than mysql_fetch_object), so you can start to collaborate with others. Table names should be in braces, e.g., {filepath} (this means the SQL will work with dbs that have prefixes.)

sinfield’s picture

sinfield commented

If the script that I wrote is contained in a block, would it not already be under the nodeapi hook, as well as all the other core hooks?

nedjo’s picture

nedjo
he/him/his
Primary language English
commented

No, the block doesn't go through nodeapi. You could load the node, using a node id, if the page you're on is in the form node/76 where 76 is the node id. The parts of the page address are accessed by the arg() function.


if (arg(0) == 'node' && is_numeric(arg(1)) && !arg(2)) {
  $node = node_load(arg(1));
  ....
}