diff --git a/src/xrt/drivers/north_star/distortion/deformation_northstar.cpp b/src/xrt/drivers/north_star/distortion/deformation_northstar.cpp
index a5b7e7355..916505592 100644
--- a/src/xrt/drivers/north_star/distortion/deformation_northstar.cpp
+++ b/src/xrt/drivers/north_star/distortion/deformation_northstar.cpp
@@ -221,10 +221,10 @@ OpticalSystem::SolveDisplayUVToRenderUV(Vector2 inputUV,
 		Vector2 error = curDisplayUV - inputUV;
 		Vector2 step = Vector2::zero();
 
-		if (!displayUVGradX.x == 0.f || !displayUVGradX.y == 0.f) {
+		if ((!displayUVGradX.x) == 0.f || (!displayUVGradX.y) == 0.f) {
 			step = step + (displayUVGradX * error.x);
 		}
-		if (!displayUVGradY.x == 0.f || !displayUVGradY.y == 0.f) {
+		if ((!displayUVGradY.x) == 0.f || (!displayUVGradY.y) == 0.f) {
 			step = step + (displayUVGradY * error.y);
 		}
 
diff --git a/src/xrt/drivers/north_star/distortion/deformation_northstar.h b/src/xrt/drivers/north_star/distortion/deformation_northstar.h
index 97aa394d1..3ac0953d2 100644
--- a/src/xrt/drivers/north_star/distortion/deformation_northstar.h
+++ b/src/xrt/drivers/north_star/distortion/deformation_northstar.h
@@ -4,15 +4,10 @@
 
 #pragma once
 
-#include <map>
 #include "utility_northstar.h"
 #include "../ns_hmd.h"
-#include <chrono>
+#include <map>
 
-using namespace std::chrono;
-
-static char *s_strLeftEye = "leftEye";
-static char *s_strRightEye = "rightEye";
 
 class OpticalSystem
 {
@@ -71,9 +66,6 @@ public:
 	void
 	UpdateClipToWorld(Matrix4x4 eyeRotationMatrix)
 	{
-		// TEST DELETEME
-		float time = clock() / (float)CLOCKS_PER_SEC;
-		float osc = sinf(time * 2 * LP_PI);
 		Matrix4x4 eyeToWorld =
 		    Matrix4x4::Translate(eyePosition) * eyeRotationMatrix;
 		eyeToWorld.m02 *= -1;
@@ -99,7 +91,7 @@ public:
 		    clipToWorld.MultiplyPoint(tmp * 2.f) - cameraPosition;
 
 		float mag = dir.Magnitude();
-		out = dir / dir.Magnitude();
+		out = dir / mag;
 		return;
 	}
 
diff --git a/src/xrt/drivers/north_star/distortion/utility_northstar.h b/src/xrt/drivers/north_star/distortion/utility_northstar.h
index d0d0d83f8..297b84dd1 100644
--- a/src/xrt/drivers/north_star/distortion/utility_northstar.h
+++ b/src/xrt/drivers/north_star/distortion/utility_northstar.h
@@ -44,6 +44,15 @@ public:
 		z = 0.f;
 	};
 
+	constexpr Vector3 &
+	operator=(const Vector3 &lhr)
+	{
+		this->x = lhr.x;
+		this->y = lhr.y;
+		this->z = lhr.z;
+		return *this;
+	}
+
 	inline static Vector3
 	Up()
 	{
@@ -139,14 +148,6 @@ public:
 		return ret;
 	}
 
-	inline void
-	copy(Vector3 &lhs, Vector3 rhs)
-	{
-		rhs.x = lhs.x;
-		rhs.y = lhs.y;
-		rhs.z = lhs.z;
-	}
-
 	inline float static Dot(Vector3 lhs, Vector3 rhs)
 	{
 		float result =
@@ -300,6 +301,14 @@ public:
 		y = _y;
 	};
 
+	constexpr Vector2 &
+	operator=(const Vector2 &lhr)
+	{
+		this->x = lhr.x;
+		this->y = lhr.y;
+		return *this;
+	}
+
 	inline static Vector2
 	zero()
 	{
@@ -434,6 +443,28 @@ public:
 		m33 = in33;
 	};
 
+	constexpr Matrix4x4 &
+	operator=(const Matrix4x4 &lhr)
+	{
+		this->m00 = lhr.m00;
+		this->m01 = lhr.m01;
+		this->m02 = lhr.m02;
+		this->m03 = lhr.m03;
+		this->m10 = lhr.m10;
+		this->m11 = lhr.m11;
+		this->m12 = lhr.m12;
+		this->m13 = lhr.m13;
+		this->m20 = lhr.m20;
+		this->m21 = lhr.m21;
+		this->m22 = lhr.m22;
+		this->m23 = lhr.m23;
+		this->m30 = lhr.m30;
+		this->m31 = lhr.m31;
+		this->m32 = lhr.m32;
+		this->m33 = lhr.m33;
+		return *this;
+	};
+
 	inline static Matrix4x4
 	Identity()
 	{
@@ -688,6 +719,16 @@ public:
 		w = in.w;
 	}
 
+	constexpr Vector4 &
+	operator=(const Vector4 &lhr)
+	{
+		this->x = lhr.x;
+		this->y = lhr.y;
+		this->z = lhr.z;
+		this->w = lhr.w;
+		return *this;
+	}
+
 	inline Matrix4x4
 	ComposeProjection()
 	{
@@ -784,6 +825,16 @@ public:
 		w = _in.w;
 	};
 
+	constexpr Quaternion &
+	operator=(const Quaternion &lhr)
+	{
+		this->x = lhr.x;
+		this->y = lhr.y;
+		this->z = lhr.z;
+		this->w = lhr.w;
+		return *this;
+	}
+
 	inline static Quaternion
 	Identity()
 	{