From 4b6c04585e6f5a301e09a8661302f74345982572 Mon Sep 17 00:00:00 2001
From: yexo <yexo@openttd.org>
Date: Thu, 25 Feb 2010 11:48:50 +0000
Subject: [PATCH] (svn r19242) -Codechange: Perfer pointer instead of reference
 (skidd13) -Cleanup: merge PopHead() and RemoveHead() into Shift()

---
 src/misc/binaryheap.hpp          | 24 ++++++++++--------------
 src/pathfinder/yapf/nodelist.hpp | 11 +++++------
 2 files changed, 15 insertions(+), 20 deletions(-)

diff --git a/src/misc/binaryheap.hpp b/src/misc/binaryheap.hpp
index c95255e10f..f90ec0b099 100644
--- a/src/misc/binaryheap.hpp
+++ b/src/misc/binaryheap.hpp
@@ -116,10 +116,10 @@ public:
 
 	/** Find the smallest item in the priority queue.
 	 *  Return the smallest item, or throw assert if empty. */
-	FORCEINLINE T& GetHead()
+	FORCEINLINE T *Begin()
 	{
 		assert(!IsEmpty());
-		return *m_items[1];
+		return m_items[1];
 	}
 
 	FORCEINLINE T *End()
@@ -129,7 +129,7 @@ public:
 
 	/** Insert new item into the priority queue, maintaining heap order.
 	 *  @return false if the queue is full. */
-	FORCEINLINE void Push(T& new_item)
+	FORCEINLINE void Push(T *new_item)
 	{
 		if (IsFull()) {
 			m_max_size *= 2;
@@ -137,31 +137,27 @@ public:
 		}
 
 		/* make place for new item */
-		uint gap = HeapifyUp(++m_size, &new_item);
-		m_items[gap] = &new_item;
+		uint gap = HeapifyUp(++m_size, new_item);
+		m_items[gap] = new_item;
 		CheckConsistency();
 	}
 
 	/** Remove and return the smallest item from the priority queue. */
-	FORCEINLINE T& PopHead()
-	{
-		T& ret = GetHead();
-		RemoveHead();
-		return ret;
-	}
-
-	/** Remove the smallest item from the priority queue. */
-	FORCEINLINE void RemoveHead()
+	FORCEINLINE T *Shift()
 	{
 		assert(!IsEmpty());
 
+		T *first = Begin();
+
 		m_size--;
 		/* at index 1 we have a gap now */
 		T *last = End();
 		uint gap = HeapifyDown(1, last);
 		/* move last item to the proper place */
 		if (!IsEmpty()) m_items[gap] = last;
+
 		CheckConsistency();
+		return first;
 	}
 
 	/** Remove item specified by index */
diff --git a/src/pathfinder/yapf/nodelist.hpp b/src/pathfinder/yapf/nodelist.hpp
index 9260c45f74..6ac3b944c3 100644
--- a/src/pathfinder/yapf/nodelist.hpp
+++ b/src/pathfinder/yapf/nodelist.hpp
@@ -93,7 +93,7 @@ public:
 	{
 		assert(m_closed.Find(item.GetKey()) == NULL);
 		m_open.Push(item);
-		m_open_queue.Push(item);
+		m_open_queue.Push(&item);
 		if (&item == m_new_node) {
 			m_new_node = NULL;
 		}
@@ -103,8 +103,7 @@ public:
 	FORCEINLINE Titem_ *GetBestOpenNode()
 	{
 		if (!m_open_queue.IsEmpty()) {
-			Titem_& item = m_open_queue.GetHead();
-			return &item;
+			return m_open_queue.Begin();
 		}
 		return NULL;
 	}
@@ -113,9 +112,9 @@ public:
 	FORCEINLINE Titem_ *PopBestOpenNode()
 	{
 		if (!m_open_queue.IsEmpty()) {
-			Titem_& item = m_open_queue.PopHead();
-			m_open.Pop(item);
-			return &item;
+			Titem_ *item = m_open_queue.Shift();
+			m_open.Pop(*item);
+			return item;
 		}
 		return NULL;
 	}