Imported Upstream version 0.6.26

share/pnp/application/helpers/rrd.php

@@ -444,6 +444,35 @@ class rrd_Core {
 		return $line;
 	}
 
+    # http://stackoverflow.com/questions/3512311/how-to-generate-lighter-darker-color-with-php
+    public static function colbright($hex, $steps) {
+        if($hex === FALSE){
+            throw new Kohana_exception("rrd::". __FUNCTION__ . "() First Parameter 'hex' is missing");
+        }
+        if($steps === FALSE){
+            throw new Kohana_exception("rrd::". __FUNCTION__ . "() Second Parameter 'steps' is missing");
+        }
+        // Steps should be between -255 and 255. Negative = darker, positive = lighter
+        $steps = max(-255, min(255, $steps));
+
+        // Normalize into a six character long hex string
+        $hex = str_replace('#', '', $hex);
+        if (strlen($hex) == 3) {
+            $hex = str_repeat(substr($hex,0,1), 2).str_repeat(substr($hex,1,1), 2).str_repeat(substr($hex,2,1), 2);
+        }
+
+        // Split into three parts: R, G and B
+        $color_parts = str_split($hex, 2);
+        $return = '#';
+
+        foreach ($color_parts as $color) {
+            $color   = hexdec($color); // Convert to decimal
+            $color   = max(0,min(255,$color + $steps)); // Adjust color
+            $return .= str_pad(dechex($color), 2, '0', STR_PAD_LEFT); // Make two char hex code
+        }
+        return $return;
+    }
+
     public static function debug($data=FALSE){
         if($data != FALSE){
 	    ob_start();