<?php
$max = "1000";								// Max resources
$userid = $_SESSION['id'];
$row = mysql_query("SELECT * FROM resource WHERE userid='$userid'") or die(mysql_error());
$row_resource = mysql_fetch_assoc($row);	// Get record
$currentValue = $row_resource['value'];		// Current value
$LUT = $row_resource['lut'];				// Last Update time
$currentTime = Time();						// Current time
$TD = $currentTime-$LUT;					// Time difference
$ADD = $TD*1;								// Resources to add per secound.
$CH = $currentValue+$ADD;					// New Resource (change to - if subtract).
if ($CH > $max) {							// If new value exceeds max new value is max
$CH = $max;
} else {									// If new value is lower then max update DB
 $result = mysql_query("UPDATE resource SET value='$CH' WHERE userid='$userid'")
or die(mysql_error());  
$result = mysql_query("UPDATE resource SET lut='$currentTime' WHERE userid='$userid'")
or die(mysql_error());   
}

echo "Resources = " . $CH;					//Show updated value.
?>