From 417f7a54f523f54d098fe4a77c6eac671593dfa1 Mon Sep 17 00:00:00 2001
From: Jan Philipp Timme <jpt.homemail@googlemail.com>
Date: Tue, 4 Jan 2011 19:25:30 +0000
Subject: [PATCH] [TASK] Improved performance by creating a lookup-table for
 the colorindex to rgb function.

---
 CharColorConverter.class.php | 26 +++++++++++++++++++++++++-
 FileImageConverter.class.php |  2 ++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/CharColorConverter.class.php b/CharColorConverter.class.php
index ee1665c..62395d6 100644
--- a/CharColorConverter.class.php
+++ b/CharColorConverter.class.php
@@ -5,6 +5,19 @@
  */
 class CharColorConverter {
 
+	/**
+	 * @var array
+	 */
+	protected $colortable;
+
+	/**
+	 * Default constructor.
+	 * @return void
+	 */
+	public function __construct() {
+		$this->buildColorTable();
+	}
+
 	/**
 	 * Returns an array with RGB for the corresponding index.
 	 * @param int $index Index from 0 to 1530. (Everything above will result the same)
@@ -34,6 +47,17 @@ class CharColorConverter {
 		return array($r, $g, $b);
 	}
 
+	/**
+	 * Creates the colortable.
+	 * @return void
+	 */
+	protected function buildColorTable() {
+		$this->colortable = array();
+		for($i = 0; $i <= 1275; $i++) {
+			$this->colortable[$i] = $this->index2rgb($i);
+		}
+	}
+
 	/**
 	 * Converts a single char to a string.
 	 * @param string $string
@@ -42,7 +66,7 @@ class CharColorConverter {
 	public function charToColor($string) {
 		if(strlen($string) === 0) throw new Exception("Empty string given!");
 		$index = ord($string) * 5;
-		$color = $this->index2rgb($index);
+		$color = $this->colortable[$index];
 		return $color;
 	}
 }
diff --git a/FileImageConverter.class.php b/FileImageConverter.class.php
index 468fdbb..a5a8e17 100644
--- a/FileImageConverter.class.php
+++ b/FileImageConverter.class.php
@@ -20,7 +20,9 @@ class FileImageConverter {
 	 * @return void
 	 */
 	public function __construct() {
+		echo "\nInitializing color translation table...";
 		$this->colorConverter = new CharColorConverter();
+		echo "done.\n";
 	}
 
 	/**