limit amount of times points are given per activity

This is a feature request. My employer will provide a patch for this shortly.

I'm doing that using rules and with a condition that evaluates a php code, example i want only a comment per hour sum points

$result = db_fetch_array(db_query("SELECT * FROM comments WHERE uid = %d AND cid != %d ORDER BY timestamp DESC LIMIT 1", $user->uid, $comment->cid));
if($result)
{
   $timestamp = $result['timestamp'];
   $last_comment_hour = date("YmdH", $timestamp);
   $now_hour = date("YmdH");
   if( $now_hour == $last_comment_hour )
      return false;
}
return true;

Obviously the rule gives the points to the user and then user points for comments has to be disabled.

Subscribing...

I'm trying to do something a little different. I'm still using rules with a custom PHP condition, but I want to set a global number of points a person can get in a day, 10 for instance. I'm not much of a php developer by any means, but this is what I have so far:

$number = db_result(db_query("SELECT SUM(points) FROM {userpoints_txn} WHERE uid = %d AND time_stamp > %d", $uid, time() - 86400));

{
   if( $number >= 10 )
      return false;
}
return true;

The problem is that this always seems to return true no matter what. I'm obviously doing something rather wrong and I'd appreciate it if someone could point out my mistake(s).

Just found out what was going wrong, the time wasn't being parsed correctly. Here's the updated code:

$today = date(Ymd);
$currentday = strtotime($today);
$number = db_result(db_query("SELECT SUM(points) FROM {userpoints_txn} WHERE uid = 1 AND time_stamp > $currentday", $uid));

{
   if( $number + 2 > 10 )
      return false;
}
return true;

I was able to make it so that it operates on a fixed day. The way I was trying to do it before made it a rolling day where it was just calculating the number of points 24 hours from whenever the person was trying. To make it operate on a rolling day (or whatever increment you'd like), you can use this code:

$currentday = time() - 86400;
$number = db_result(db_query("SELECT SUM(points) FROM {userpoints_txn} WHERE uid = 1 AND time_stamp > $currentday", $uid));

{
   if( $number + 2 > 10 )
      return false;
}
return true;

Also, some notes about my if() statement. I realized that if someone had, let's say, 9 points, and they performed an action worth 2 points, it would return true, even though they've exceeded the limit for the day. Therefore, I added + 2 to the sum of the points they have currently as a means to check how many points they will have. I'll just adjust it manually for each rule.

Note that you can do this in an implementation of hook_userpoints() with $op 'before'. If you return FALSE in that hook, the transaction will automatically be blocked.

This will allow to block all transaction, no matter where they are coming from. Instead of a fixed 2, you want to user $params['points'] and $params['uid'] for the user.

Als, it would be great if you could have a look at the existing documentation at http://drupal.org/documentation/modules/userpoints and see if you can somehow add your code there, for example as a separate How-To page (add child page).

That will be much easier to find than in here...