From dda4b41cac6264d7ddd7ee1004c5edce919a3ec0 Mon Sep 17 00:00:00 2001
From: Hans-Christian Ebke <ebke@cs.rwth-aachen.de>
Date: Mon, 9 Nov 2015 22:55:42 +0100
Subject: [PATCH] C++11: Got rid of narrowing conversion warnings in legacy
 code.

Added explicit static_cast along with static SFINAE checks to VectorT
constructor.
---
 src/OpenMesh/Core/Geometry/VectorT.hh     | 17 +++++++++++++++++
 src/OpenMesh/Core/Geometry/VectorT_inc.hh |  6 ++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/OpenMesh/Core/Geometry/VectorT.hh b/src/OpenMesh/Core/Geometry/VectorT.hh
index 38a463e8..7be16f0e 100644
--- a/src/OpenMesh/Core/Geometry/VectorT.hh
+++ b/src/OpenMesh/Core/Geometry/VectorT.hh
@@ -92,6 +92,23 @@ namespace OpenMesh {
 //== CLASS DEFINITION =========================================================
 
 
+#if CPP11_ENABLED
+/*
+ * Helpers for VectorT
+ */
+namespace {
+template<typename... Ts>
+struct are_convertible_to;
+
+template<typename To, typename From, typename... Froms>
+struct are_convertible_to<To, From, Froms...> {
+    static constexpr bool value = std::is_convertible<From, To>::value && are_convertible_to<To, Froms...>::value;
+};
+template<typename To, typename From>
+struct are_convertible_to<To, From> : public std::is_convertible<From, To> {};
+}
+#endif
+
 
 /** The N values of the template Scalar type are the only data members
     of the class VectorT<Scalar,N>. This guarantees 100% compatibility
diff --git a/src/OpenMesh/Core/Geometry/VectorT_inc.hh b/src/OpenMesh/Core/Geometry/VectorT_inc.hh
index 6fd4d3c3..3f045a19 100644
--- a/src/OpenMesh/Core/Geometry/VectorT_inc.hh
+++ b/src/OpenMesh/Core/Geometry/VectorT_inc.hh
@@ -102,8 +102,10 @@ public:
       vectorize(v);
   }
 
-  template<typename... T, typename = typename std::enable_if<sizeof...(T) == DIM>::type>
-  constexpr VectorT(T... vs) : Base {vs...}
+  template<typename... T,
+      typename = typename std::enable_if<sizeof...(T) == DIM>::type,
+      typename = typename std::enable_if<are_convertible_to<float, T...>::value>::type>
+  constexpr VectorT(T... vs) : Base { static_cast<Scalar>(vs)...}
   { }
 #else
   /// special constructor for 1D vectors