Fixed entity chunking.

Sand simulator was off, sand in negative coords wouldn't fall properly

git-svn-id: http://mc-server.googlecode.com/svn/trunk@1489 0a769ca7-a7f5-676a-18bf-c427514a06d6

source/FallingBlock.h

@@ -23,6 +23,7 @@ class cFallingBlock :
 public:
 	CLASS_PROTODEF(cFallingBlock);
 
+	/// Creates a new falling block. a_BlockPosition is expected in world coords
 	cFallingBlock(const Vector3i & a_BlockPosition, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
 
 	BLOCKTYPE  GetBlockType(void) const { return m_BlockType; }
@@ -36,7 +37,7 @@ public:
 private:
 	BLOCKTYPE  m_BlockType;
 	NIBBLETYPE m_BlockMeta;
-	Vector3i   m_OriginalPosition;
+	Vector3i   m_OriginalPosition;  // Position where the falling block has started, in world coords
 } ;