From 907fdd26fc46bdf3027c2075364e5281b6c6badc Mon Sep 17 00:00:00 2001
From: Jordan Woyak <jordan.woyak@gmail.com>
Date: Mon, 19 Oct 2020 16:34:00 -0500
Subject: [PATCH] WiimoteEmu: Use quaternions for orientation.

---
 Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.cpp | 11 ++++++-----
 Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.h   |  2 +-
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.cpp b/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.cpp
index 3bc2fe0b63..b492b3bc14 100644
--- a/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.cpp
+++ b/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.cpp
@@ -734,10 +734,10 @@ Common::Matrix44 Wiimote::GetTransformation(const Common::Matrix33& extra_rotati
          Common::Matrix44::Translate(-m_swing_state.position - m_point_state.position);
 }
 
-Common::Matrix33 Wiimote::GetOrientation() const
+Common::Quaternion Wiimote::GetOrientation() const
 {
-  return Common::Matrix33::RotateZ(float(MathUtil::TAU / -4 * IsSideways())) *
-         Common::Matrix33::RotateX(float(MathUtil::TAU / 4 * IsUpright()));
+  return Common::Quaternion::RotateZ(float(MathUtil::TAU / -4 * IsSideways())) *
+         Common::Quaternion::RotateX(float(MathUtil::TAU / 4 * IsUpright()));
 }
 
 Common::Vec3 Wiimote::GetTotalAcceleration() const
@@ -758,8 +758,9 @@ Common::Vec3 Wiimote::GetTotalAngularVelocity() const
 
 Common::Matrix44 Wiimote::GetTotalTransformation() const
 {
-  return GetTransformation(Common::Matrix33::FromQuaternion(m_imu_cursor_state.rotation) *
-                           Common::Matrix33::RotateX(m_imu_cursor_state.recentered_pitch));
+  return GetTransformation(Common::Matrix33::FromQuaternion(
+      m_imu_cursor_state.rotation *
+      Common::Quaternion::RotateX(m_imu_cursor_state.recentered_pitch)));
 }
 
 }  // namespace WiimoteEmu
diff --git a/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.h b/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.h
index a01d4c545f..fac1dc6d31 100644
--- a/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.h
+++ b/Source/Core/Core/HW/WiimoteEmu/WiimoteEmu.h
@@ -162,7 +162,7 @@ private:
   GetTransformation(const Common::Matrix33& extra_rotation = Common::Matrix33::Identity()) const;
 
   // Returns the world rotation from the effects of sideways/upright settings.
-  Common::Matrix33 GetOrientation() const;
+  Common::Quaternion GetOrientation() const;
 
   Common::Vec3 GetTotalAcceleration() const;
   Common::Vec3 GetTotalAngularVelocity() const;