From c70c079efc4fcfe9e9b2c29cd82f67faa63c827f Mon Sep 17 00:00:00 2001
From: Pascal Serrarens <pascal@passervr.com>
Date: Tue, 18 Jun 2024 11:45:38 +0200
Subject: [PATCH] Add spherical subtract

---
 Spherical.cpp          | 14 ++++++++++++++
 Spherical.h            |  5 +++++
 test/Spherical_test.cc |  6 +++---
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/Spherical.cpp b/Spherical.cpp
index b521c77..b09fda0 100644
--- a/Spherical.cpp
+++ b/Spherical.cpp
@@ -71,6 +71,19 @@ Spherical Spherical::operator-() const {
   return v;
 }
 
+Spherical Spherical::operator-(const Spherical &s2) const {
+  // let's do it the easy way...
+  Vector3 v1 = Vector3(*this);
+  Vector3 v2 = Vector3(s2);
+  Vector3 v = v1 - v2;
+  Spherical r = Spherical(v);
+  return r;
+}
+Spherical Spherical::operator-=(const Spherical &v) {
+  *this = *this - v;
+  return *this;
+}
+
 Spherical Spherical::operator+(const Spherical &s2) const {
   // let's do it the easy way...
   Vector3 v1 = Vector3(*this);
@@ -140,6 +153,7 @@ Spherical Spherical::operator*=(float f) {
   this->distance *= f;
   return *this;
 }
+
 Spherical Passer::LinearAlgebra::operator/(const Spherical &v, float f) {
   return Spherical(v.distance / f, v.horizontalAngle, v.verticalAngle);
 }
diff --git a/Spherical.h b/Spherical.h
index 3bbf72e..4e285e3 100644
--- a/Spherical.h
+++ b/Spherical.h
@@ -90,6 +90,11 @@ public:
   /// vertically. Distance will stay the same.
   Spherical operator-() const;
 
+  /// @brief Subtract a spherical vector from this vector
+  /// @param v The vector to subtract
+  /// @return The result of the subtraction
+  Spherical operator-(const Spherical &v) const;
+  Spherical operator-=(const Spherical &v);
   /// @brief Add a spherical vector to this vector
   /// @param v The vector to add
   /// @return The result of the addition
diff --git a/test/Spherical_test.cc b/test/Spherical_test.cc
index 5e89ce2..0ffae7f 100644
--- a/test/Spherical_test.cc
+++ b/test/Spherical_test.cc
@@ -142,9 +142,9 @@ TEST(Spherical, Addition) {
 
   v2 = Spherical(1, -45, 0);
   r = v1 + v2;
-  EXPECT_FLOAT_EQ(r.distance, sqrtf(2)) << "Addition(0 0 0)";
-  EXPECT_FLOAT_EQ(r.horizontalAngle, 0) << "Addition(0 0 0)";
-  EXPECT_FLOAT_EQ(r.verticalAngle, 0) << "Addition(0 0 0)";
+  EXPECT_FLOAT_EQ(r.distance, sqrtf(2)) << "Addition(1 -45 0)";
+  EXPECT_FLOAT_EQ(r.horizontalAngle, 0) << "Addition(1 -45 0)";
+  EXPECT_FLOAT_EQ(r.verticalAngle, 0) << "Addition(1 -45 0)";
 
   v2 = Spherical(1, 0, 90);
   r = v1 + v2;