From c49457a817d3f7d1301f56c4ccda28d610cc607d Mon Sep 17 00:00:00 2001
From: Eryn Wells <eryn@erynwells.me>
Date: Sat, 9 Aug 2014 11:55:10 -0700
Subject: [PATCH] Implement Normalized, LinearCombination, and operator<< on
 Vector4s

---
 src/basics/vector.cc | 36 ++++++++++++++++++++++++++++++++++++
 src/basics/vector.hh | 12 +++++++++++-
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/src/basics/vector.cc b/src/basics/vector.cc
index a2d65f8..af09696 100644
--- a/src/basics/vector.cc
+++ b/src/basics/vector.cc
@@ -224,6 +224,42 @@ operator*(const Double& lhs,
     return rhs * lhs;
 }
 
+
+/*
+ * charles::basics::Normalized --
+ */
+Vector4
+Normalized(const Vector4& v)
+{
+    return Vector4(v).Normalize();
+}
+
+
+/*
+ * charles::basics::LinearCombination --
+ */
+Vector4
+LinearCombination(const Double k1, const Vector4& v1,
+                  const Double k2, const Vector4& v2,
+                  const Double k3, const Vector4& v3)
+{
+    return Vector4(k1 * v1.X() + k2 * v2.X() + k3 * v3.X(),
+                   k1 * v1.Y() + k2 * v2.Y() + k3 * v3.Y(),
+                   k1 * v1.Z() + k2 * v2.Z() + k3 * v3.Z());
+}
+
+
+/*
+ * charles::basics::operator<< --
+ */
+std::ostream &
+operator<<(std::ostream &os, const Vector3 &v)
+{
+    // Stream the vector like this: <x, y, z>
+    os << "<" << v.X() << ", " << v.Y() << ", " << v.Z() << ">";
+    return os;
+}
+
 } /* namespace basics */
 } /* namespace charles */
 
diff --git a/src/basics/vector.hh b/src/basics/vector.hh
index 4069d87..e5ce24c 100644
--- a/src/basics/vector.hh
+++ b/src/basics/vector.hh
@@ -6,6 +6,8 @@
 #ifndef __BASICS_VECTOR_HH__
 #define __BASICS_VECTOR_HH__
 
+#include <ostream>
+
 #include "basics/matrix.hh"
 #include "basics/types.hh"
 
@@ -63,7 +65,15 @@ Vector4 operator*(const Double& lhs, const Vector4& rhs);
 
 
 /** Normalize the given vector and return a copy of it. */
-Vector4& Normalized(const Vector4& v);
+Vector4 Normalized(const Vector4& v);
+
+
+Vector4 LinearCombination(const Double k1, const Vector4& v1,
+                          const Double k2, const Vector4& v2,
+                          const Double k3, const Vector4& v3);
+
+
+std::ostream& operator<<(std::ostream& ost, const Vector4& v);
 
 } /* namespace basics */
 } /* namespace charles */