From 122ee3a7a11b196a26b6cdc60400b01efca56b41 Mon Sep 17 00:00:00 2001
From: Mikko Mononen <memononen@gmail.com>
Date: Thu, 8 Jul 2010 12:04:43 +0000
Subject: [PATCH] Issue 86:Tiled world consisting of one tile - dtNavMesh::init
 fails. ___NOTE: dtPolyRef format changed___

---
 Detour/Include/DetourNavMesh.h  | 6 +++---
 Detour/Source/DetourNavMesh.cpp | 8 ++++++--
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/Detour/Include/DetourNavMesh.h b/Detour/Include/DetourNavMesh.h
index c8d998a..606c096 100644
--- a/Detour/Include/DetourNavMesh.h
+++ b/Detour/Include/DetourNavMesh.h
@@ -452,14 +452,14 @@ public:
 	// Encodes a tile id.
 	inline dtPolyRef encodePolyId(unsigned int salt, unsigned int it, unsigned int ip) const
 	{
-		return (salt << (m_polyBits+m_tileBits)) | ((it+1) << m_polyBits) | ip;
+		return (salt << (m_polyBits+m_tileBits)) | (it << m_polyBits) | ip;
 	}
 	
 	// Decodes a tile id.
 	inline void decodePolyId(dtPolyRef ref, unsigned int& salt, unsigned int& it, unsigned int& ip) const
 	{
 		salt = (ref >> (m_polyBits+m_tileBits)) & ((1<<m_saltBits)-1);
-		it = ((ref >> m_polyBits) - 1) & ((1<<m_tileBits)-1);
+		it = (ref >> m_polyBits) & ((1<<m_tileBits)-1);
 		ip = ref & ((1<<m_polyBits)-1);
 	}
 
@@ -472,7 +472,7 @@ public:
 	// Decodes a tile id.
 	inline unsigned int decodePolyIdTile(dtPolyRef ref) const
 	{
-		return ((ref >> m_polyBits) - 1) & ((1<<m_tileBits)-1);
+		return (ref >> m_polyBits) & ((1<<m_tileBits)-1);
 	}
 	
 	// Decodes a poly id.
diff --git a/Detour/Source/DetourNavMesh.cpp b/Detour/Source/DetourNavMesh.cpp
index fb10ee0..e307018 100644
--- a/Detour/Source/DetourNavMesh.cpp
+++ b/Detour/Source/DetourNavMesh.cpp
@@ -214,6 +214,7 @@ bool dtNavMesh::init(const dtNavMeshParams* params)
 	m_nextFree = 0;
 	for (int i = m_maxTiles-1; i >= 0; --i)
 	{
+		m_tiles[i].salt = 1;
 		m_tiles[i].next = m_nextFree;
 		m_nextFree = &m_tiles[i];
 	}
@@ -832,8 +833,11 @@ bool dtNavMesh::removeTile(dtTileRef ref, unsigned char** data, int* dataSize)
 	tile->detailTris = 0;
 	tile->bvTree = 0;
 	tile->offMeshCons = 0;
-		
-	tile->salt++;
+
+	// Update salt, salt should never be zero.
+	tile->salt = (tile->salt+1) & ((1<<m_saltBits)-1);
+	if (tile->salt == 0)
+		tile->salt++;
 
 	// Add to free list.
 	tile->next = m_nextFree;