From 719a9693103b6604041d7e615784bdc4b360eb40 Mon Sep 17 00:00:00 2001
From: Justin Aquadro <jaquadro@gmail.com>
Date: Sat, 10 Nov 2012 12:11:43 -0500
Subject: [PATCH] Fixed bug where empty chunks below the heightmap were not
 written.

---
 SubstrateCS/Source/AnvilChunk.cs | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/SubstrateCS/Source/AnvilChunk.cs b/SubstrateCS/Source/AnvilChunk.cs
index 9ff47e0..f0971f5 100644
--- a/SubstrateCS/Source/AnvilChunk.cs
+++ b/SubstrateCS/Source/AnvilChunk.cs
@@ -304,6 +304,16 @@ namespace Substrate
             return LoadTree(tree);
         }
 
+        private bool ShouldIncludeSection (AnvilSection section)
+        {
+            int y = (section.Y + 1) * section.Blocks.YDim;
+            for (int i = 0; i < _heightMap.Length; i++)
+                if (_heightMap[i] > y)
+                    return true;
+
+            return !section.CheckEmpty();
+        }
+
         public TagNode BuildTree ()
         {
             TagNodeCompound level = _tree.Root["Level"] as TagNodeCompound;
@@ -313,7 +323,7 @@ namespace Substrate
 
             TagNodeList sections = new TagNodeList(TagType.TAG_COMPOUND);
             for (int i = 0; i < _sections.Length; i++)
-                if (!_sections[i].CheckEmpty())
+                if (ShouldIncludeSection(_sections[i]))
                     sections.Add(_sections[i].BuildTree());
 
             levelCopy["Sections"] = sections;