From f9dc00712da03bd31943bc3e09c0a8483a29a414 Mon Sep 17 00:00:00 2001
From: trotFunky <teo.couprie_diaz@telecom-sudparis.eu>
Date: Tue, 22 Oct 2019 01:11:01 +0200
Subject: [PATCH] Added cross and dot products Fixed T initializers Constified
 functions that could be marked const.

---
 src/Vectors.h | 40 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 39 insertions(+), 1 deletion(-)

diff --git a/src/Vectors.h b/src/Vectors.h
index 2991d92..29bdf82 100644
--- a/src/Vectors.h
+++ b/src/Vectors.h
@@ -18,7 +18,7 @@ struct CoordinatesVector
 
     /// Computes the euclidean norm of the vector.
     /// \return The magnitude.
-    double magnitude()
+    double magnitude() const
     {
         // TODO : Save magnitude if the vector has not been modified.
         double sum_of_squares = 0;
@@ -44,6 +44,19 @@ struct CoordinatesVector
         }
     }
 
+
+    template <typename U = T>
+    typename std::enable_if<std::is_arithmetic<U>::value,T>::type
+    dot_product(const CoordinatesVector<T,N>& operand) const
+    {
+        T result = 0;
+        for (unsigned int i = 0;i<N;i++)
+        {
+            result += coordinates[i]*operand.coordinates[i];
+        }
+        return result;
+    }
+
     // Use SFINAE to declare the function if and only if the type is arithmetic
     template <typename Scalar>
     typename std::enable_if<std::is_arithmetic<Scalar>::value,CoordinatesVector<T,N>>::type
@@ -106,6 +119,12 @@ struct Vec2 : public CoordinatesVector<T,2>
 
     Vec2() = default;
 
+    Vec2(T x_axis, T y_axis)
+    {
+        x = x_axis;
+        y = y_axis;
+    }
+
     Vec2(const Vec2<T>& original): x(CoordinatesVector<T,2>::coordinates[0]), y(CoordinatesVector<T,2>::coordinates[1])
     {
         std::copy(std::begin(original.coordinates), std::end(original.coordinates), std::begin(CoordinatesVector<T,2>::coordinates));
@@ -140,6 +159,13 @@ struct Vec3 : CoordinatesVector<T,3>
 
     Vec3() = default;
 
+    Vec3(T x_axis, T y_axis, T z_axis)
+    {
+        x = x_axis;
+        y = y_axis;
+        z = z_axis;
+    }
+
     Vec3(const Vec3<T>& original): x(CoordinatesVector<T,3>::coordinates[0]), y(CoordinatesVector<T,3>::coordinates[1]), z(CoordinatesVector<T,3>::coordinates[2])
     {
         std::copy(std::begin(original.coordinates), std::end(original.coordinates), std::begin(CoordinatesVector<T,3>::coordinates));
@@ -154,6 +180,18 @@ struct Vec3 : CoordinatesVector<T,3>
         }
     }
 
+    template <typename U = T>
+    typename std::enable_if<std::is_arithmetic<U>::value,Vec3<T>>::type
+    cross_product(const Vec3<T>& operand) const
+    {
+        Vec3<T> normal_vector{0,0,0};
+        normal_vector.x = y*operand.z - z*operand.y;
+        normal_vector.y = z*operand.x - x*operand.z;
+        normal_vector.z = x*operand.y - y*operand.x;
+
+        return normal_vector;
+    }
+
     Vec3& operator=(const Vec3<T>& original)
     {
         if (this != &original)