From 19928ff5e8a1dbb083b12bb019d3cbf8bf964ac7 Mon Sep 17 00:00:00 2001
From: colymba <thierry@colymba.com>
Date: Sat, 19 Oct 2013 14:46:23 +0300
Subject: [PATCH] NEW GDBackend can save interlaced image

Disabled by default use config GDBackend.image_interlace: 1 to enable
---
 filesystem/GD.php | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/filesystem/GD.php b/filesystem/GD.php
index e4af07982..6788b2597 100644
--- a/filesystem/GD.php
+++ b/filesystem/GD.php
@@ -7,6 +7,7 @@
 class GDBackend extends Object implements Image_Backend {
 	protected $gd, $width, $height;
 	protected $quality;
+	protected $interlace;
 	
 	/**
 	 * @config
@@ -14,6 +15,12 @@ class GDBackend extends Object implements Image_Backend {
 	 */
 	private static $default_quality = 75;
 
+	/**
+	 * @config
+	 * @var integer
+	 */
+	private static $image_interlace = 0;
+
 	/**
 	 * Set the default image quality.
 	 *
@@ -56,6 +63,7 @@ class GDBackend extends Object implements Image_Backend {
 		parent::__construct();
 
 		$this->quality = $this->config()->default_quality;
+		$this->interlace = $this->config()->image_interlace;
 	}
 	
 	public function setImageResource($resource) {
@@ -455,6 +463,9 @@ class GDBackend extends Object implements Image_Backend {
 				case "jpeg": case "jpg": case "jpe": $type = IMAGETYPE_JPEG; break;
 				default: $type = IMAGETYPE_PNG; break;
 			}
+
+			// if $this->interlace != 0, the output image will be interlaced
+			imageinterlace ($this->gd, $this->interlace);
 			
 			// if the extension does not exist, the file will not be created!