From 623f21aedd9a0fcdef5db9efd9a05e9d73815bd3 Mon Sep 17 00:00:00 2001
From: Hartmut Seichter <hartmut@technotecture.com>
Date: Tue, 7 Jun 2022 17:27:15 +0200
Subject: [PATCH] proper zero values for vectors

---
 src/core/include/pw/core/point.hpp  |  2 +-
 src/core/include/pw/core/vector.hpp | 10 +++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/core/include/pw/core/point.hpp b/src/core/include/pw/core/point.hpp
index a07a1a3..5a541ca 100644
--- a/src/core/include/pw/core/point.hpp
+++ b/src/core/include/pw/core/point.hpp
@@ -32,7 +32,7 @@ struct point_ {
 
     using value_type = T_;
 
-	T_ x, y;
+    T_ x {0}, y {0};
 
     point_() = default;
 	point_(T_ x_,T_ y_) : x(x_), y(y_) {}
diff --git a/src/core/include/pw/core/vector.hpp b/src/core/include/pw/core/vector.hpp
index 05ae7fa..08a28d3 100644
--- a/src/core/include/pw/core/vector.hpp
+++ b/src/core/include/pw/core/vector.hpp
@@ -54,6 +54,8 @@ struct vector2_ : matrix_<2,1,T> {
         return std::acos( dot( a.normalized(), b.normalized() ) );
     }
 
+    static constexpr auto zero() { return vector2_<T>(0,0); }
+
 };
 
 template <typename T>
@@ -84,7 +86,9 @@ struct vector3_ : matrix_<3,1,T>  {
     inline auto xy() const { return vector2_( { x(),y() } ); }
     inline auto homogenous(T w = 1) const { return matrix_<4,1,T>( { x(),y(),z(),w } ); }
 
-    inline static constexpr vector3_ cross(const vector3_& lhs,const vector3_& rhs) {
+    inline static constexpr vector3_ cross(const vector3_& lhs,
+                                           const vector3_& rhs)
+    {
         return vector3_( {
                              lhs[1] * rhs[2] - rhs[1] * lhs[2],
                              lhs[2] * rhs[0] - rhs[2] * lhs[0],
@@ -104,6 +108,8 @@ struct vector3_ : matrix_<3,1,T>  {
     inline static vector3_<T> x_axis() { return vector3_<T> ( { T(1), T(0), T(0) } ); }
     inline static vector3_<T> y_axis() { return vector3_<T> ( { T(0), T(1), T(0) } ); }
     inline static vector3_<T> z_axis() { return vector3_<T> ( { T(0), T(0), T(1) } ); }
+
+    static constexpr auto zero() { return vector3_(0,0,0); }
 };
 
 template <typename T>
@@ -134,6 +140,8 @@ struct vector4_ : matrix_<4,1,T>  {
 
 	inline auto project() const { return vector3_<T>({ x()/w(),y()/w(),z()/w() } ); }
 
+    static constexpr auto zero() { return vector2_<T>(0,0,0,0); }
+
 };
 
 //