From 1f53ca5f4c2736ab060d93885d9bd956f14ae430 Mon Sep 17 00:00:00 2001
From: Perttu Ahola <celeron55@gmail.com>
Date: Fri, 25 Nov 2011 22:45:55 +0200
Subject: [PATCH] Modify CONTENT_AIR and CONTENT_IGNORE handling in nodedef.cpp

---
 src/nodedef.cpp | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/nodedef.cpp b/src/nodedef.cpp
index 52d9fc8b..7855ffef 100644
--- a/src/nodedef.cpp
+++ b/src/nodedef.cpp
@@ -330,7 +330,10 @@ public:
 			f.diggable = false;
 			f.buildable_to = true;
 			f.air_equivalent = true;
-			set(CONTENT_AIR, f);
+			// Insert directly into containers
+			content_t c = CONTENT_AIR;
+			m_content_features[c] = f;
+			m_name_id_mapping.set(c, f.name);
 		}
 		// Set CONTENT_IGNORE
 		{
@@ -346,7 +349,10 @@ public:
 			// A way to remove accidental CONTENT_IGNOREs
 			f.buildable_to = true;
 			f.air_equivalent = true;
-			set(CONTENT_IGNORE, f);
+			// Insert directly into containers
+			content_t c = CONTENT_IGNORE;
+			m_content_features[c] = f;
+			m_name_id_mapping.set(c, f.name);
 		}
 	}
 	// CONTENT_IGNORE = not found
@@ -415,6 +421,12 @@ public:
 		infostream<<"registerNode: registering content id \""<<c
 				<<"\": name=\""<<def.name<<"\""<<std::endl;
 		assert(c <= MAX_CONTENT);
+		// Don't allow redefining CONTENT_IGNORE (but allow air)
+		if(def.name == "ignore" || c == CONTENT_IGNORE){
+			infostream<<"registerNode: WARNING: Ignoring "
+					<<"CONTENT_IGNORE redefinition"<<std::endl;
+			return;
+		}
 		// Check that the special contents are not redefined as different id
 		// because it would mess up everything
 		if((def.name == "ignore" && c != CONTENT_IGNORE) ||