Changeset 3031 for trunk/system/libraries/drivers/Captcha/Alpha.php

Timestamp:

07/10/2008 11:06:23 AM (5 months ago)

Author:

Geert

Message:

A few minor tweaks to Basic and Alpha Captcha style in order to preserve enough readability and make both styles differ a bit more.

Also changed internal terminology to the "official" convention: http://en.wikipedia.org/wiki/Challenge-response_authentication

Files:

• trunk/system/libraries/drivers/Captcha/Alpha.php (modified) (4 diffs)

trunk/system/libraries/drivers/Captcha/Alpha.php

@@ -1 +1 @@
 <?php defined('SYSPATH') or die('No direct script access.');
 /**
- * Captcha driver for "basic" style.
+ * Captcha driver for "alpha" style.
  *
  * $Id$
@@ -39 +39 @@
                 $this->image_gradient($color1, $color2);
 
+                // Add a few random circles
+                for ($i = 0, $count = mt_rand(10, Captcha::$config['complexity'] * 3); $i < $count; $i++)
+                {
+                        $color = imagecolorallocatealpha($this->image, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255), mt_rand(80, 120));
+                        $size = mt_rand(5, Captcha::$config['height'] / 3);
+                        imagefilledellipse($this->image, mt_rand(0, Captcha::$config['width']), mt_rand(0, Captcha::$config['height']), $size, $size, $color);
+                }
+
                 // Calculate character font-size and spacing
-                $default_size = min(Captcha::$config['width'], Captcha::$config['height'] * 2) / strlen(Captcha::$answer);
-                $spacing = (int) (Captcha::$config['width'] * 0.9 / strlen(Captcha::$answer));
+                $default_size = min(Captcha::$config['width'], Captcha::$config['height'] * 2) / strlen(Captcha::$response);
+                $spacing = (int) (Captcha::$config['width'] * 0.9 / strlen(Captcha::$response));
 
                 // Background alphabetic character attributes
@@ -48 +56 @@
 
                 // Draw each Captcha character with varying attributes
-                for ($i = 0, $strlen = strlen(Captcha::$answer); $i < $strlen; $i++)
+                for ($i = 0, $strlen = strlen(Captcha::$response); $i < $strlen; $i++)
                 {
                         $angle = mt_rand(-40, 20);
                         // Scale the character size on image height
                         $size = $default_size / 10 * mt_rand(8, 12);
-                        $box = imageftbbox($size, $angle, Captcha::$config['font'], Captcha::$answer[$i]);
+                        $box = imageftbbox($size, $angle, Captcha::$config['font'], Captcha::$response[$i]);
 
                         // Calculate character starting coordinates
@@ -64 +72 @@
 
                         // Write text character to image
-                        imagefttext($this->image, $size, $angle, $x, $y, $color, Captcha::$config['font'], Captcha::$answer[$i]);
+                        imagefttext($this->image, $size, $angle, $x, $y, $color, Captcha::$config['font'], Captcha::$response[$i]);
 
                         // Draw "ghost" alphabetic character
-                        $text_color = imagecolorallocatealpha($this->image, mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand(60, 120));
-                        $char = substr($chars, mt_rand(0,14), 1);
-                        imagettftext($this->image, $size, ($angle + (mt_rand(5,10))), ($x - (mt_rand(5,10))), ($y + (mt_rand(5,10))), $text_color, Captcha::$config['font'], $char);
-
+                        $text_color = imagecolorallocatealpha($this->image, mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand(70, 120));
+                        $char = substr($chars, mt_rand(0, 14), 1);
+                        imagettftext($this->image, $size * 2, mt_rand(-45, 45), ($x - (mt_rand(5, 10))), ($y + (mt_rand(5, 10))), $text_color, Captcha::$config['font'], $char);
                 }