From ad3c70bbc8b9f486d08cced1e337015ba4e372d5 Mon Sep 17 00:00:00 2001
From: Lynix <lynix680@gmail.com>
Date: Sat, 3 Jan 2015 21:50:37 +0100
Subject: [PATCH] Added SparsePtr substraction operator

Former-commit-id: e2dadc06b1f1abbd257689e6eaee77ebbfa0af5b
---
 include/Nazara/Core/SparsePtr.hpp | 2 ++
 include/Nazara/Core/SparsePtr.inl | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/include/Nazara/Core/SparsePtr.hpp b/include/Nazara/Core/SparsePtr.hpp
index 74a64425d..8d104827c 100644
--- a/include/Nazara/Core/SparsePtr.hpp
+++ b/include/Nazara/Core/SparsePtr.hpp
@@ -10,6 +10,7 @@
 ///FIXME: Est-ce que SparsePtr est vraiment le meilleur nom pour cette classe ?
 
 #include <Nazara/Prerequesites.hpp>
+#include <cstddef>
 #include <type_traits>
 
 template<typename T>
@@ -46,6 +47,7 @@ class NzSparsePtr
 
 		NzSparsePtr operator+(int count) const;
 		NzSparsePtr operator-(int count) const;
+		std::ptrdiff_t operator-(const NzSparsePtr& ptr) const;
 
 		NzSparsePtr& operator+=(int count);
 		NzSparsePtr& operator-=(int count);
diff --git a/include/Nazara/Core/SparsePtr.inl b/include/Nazara/Core/SparsePtr.inl
index 661c9292a..eb6c988ae 100644
--- a/include/Nazara/Core/SparsePtr.inl
+++ b/include/Nazara/Core/SparsePtr.inl
@@ -133,6 +133,12 @@ NzSparsePtr<T> NzSparsePtr<T>::operator-(int count) const
 	return NzSparsePtr(m_ptr - count*m_stride, m_stride);
 }
 
+template<typename T>
+std::ptrdiff_t NzSparsePtr<T>::operator-(const NzSparsePtr& ptr) const
+{
+	return (m_ptr - ptr.m_ptr)/m_stride;
+}
+
 template<typename T>
 NzSparsePtr<T>& NzSparsePtr<T>::operator+=(int count)
 {