diff --git a/Marlin/src/libs/vector_3.cpp b/Marlin/src/libs/vector_3.cpp
index e4fe0afaac..dfed6820e2 100644
--- a/Marlin/src/libs/vector_3.cpp
+++ b/Marlin/src/libs/vector_3.cpp
@@ -51,22 +51,22 @@ vector_3::vector_3() : x(0), y(0), z(0) { }
 
 vector_3::vector_3(float x_, float y_, float z_) : x(x_), y(y_), z(z_) { }
 
-vector_3 vector_3::cross(vector_3 left, vector_3 right) {
+vector_3 vector_3::cross(const vector_3 &left, const vector_3 &right) {
   return vector_3(left.y * right.z - left.z * right.y,
                   left.z * right.x - left.x * right.z,
                   left.x * right.y - left.y * right.x);
 }
 
-vector_3 vector_3::operator+(vector_3 v) { return vector_3((x + v.x), (y + v.y), (z + v.z)); }
-vector_3 vector_3::operator-(vector_3 v) { return vector_3((x - v.x), (y - v.y), (z - v.z)); }
+vector_3 vector_3::operator+(const vector_3 &v) { return vector_3((x + v.x), (y + v.y), (z + v.z)); }
+vector_3 vector_3::operator-(const vector_3 &v) { return vector_3((x - v.x), (y - v.y), (z - v.z)); }
 
-vector_3 vector_3::get_normal() {
+vector_3 vector_3::get_normal() const {
   vector_3 normalized = vector_3(x, y, z);
   normalized.normalize();
   return normalized;
 }
 
-float vector_3::get_length() { return SQRT(sq(x) + sq(y) + sq(z)); }
+float vector_3::get_length() const { return SQRT(sq(x) + sq(y) + sq(z)); }
 
 void vector_3::normalize() {
   const float inv_length = RSQRT(sq(x) + sq(y) + sq(z));
@@ -75,13 +75,11 @@ void vector_3::normalize() {
   z *= inv_length;
 }
 
-void vector_3::apply_rotation(matrix_3x3 matrix) {
-  const float resultX = x * matrix.matrix[3 * 0 + 0] + y * matrix.matrix[3 * 1 + 0] + z * matrix.matrix[3 * 2 + 0],
-              resultY = x * matrix.matrix[3 * 0 + 1] + y * matrix.matrix[3 * 1 + 1] + z * matrix.matrix[3 * 2 + 1],
-              resultZ = x * matrix.matrix[3 * 0 + 2] + y * matrix.matrix[3 * 1 + 2] + z * matrix.matrix[3 * 2 + 2];
-  x = resultX;
-  y = resultY;
-  z = resultZ;
+void vector_3::apply_rotation(const matrix_3x3 &matrix) {
+  const float _x = x * matrix.matrix[3 * 0 + 0] + y * matrix.matrix[3 * 1 + 0] + z * matrix.matrix[3 * 2 + 0],
+              _y = x * matrix.matrix[3 * 0 + 1] + y * matrix.matrix[3 * 1 + 1] + z * matrix.matrix[3 * 2 + 1],
+              _z = x * matrix.matrix[3 * 0 + 2] + y * matrix.matrix[3 * 1 + 2] + z * matrix.matrix[3 * 2 + 2];
+  x = _x; y = _y; z = _z;
 }
 
 void vector_3::debug(const char * const title) {
@@ -95,7 +93,7 @@ void vector_3::debug(const char * const title) {
   SERIAL_EOL();
 }
 
-void apply_rotation_xyz(matrix_3x3 matrix, float &x, float &y, float &z) {
+void apply_rotation_xyz(const matrix_3x3 &matrix, float &x, float &y, float &z) {
   vector_3 vector = vector_3(x, y, z);
   vector.apply_rotation(matrix);
   x = vector.x;
@@ -103,7 +101,7 @@ void apply_rotation_xyz(matrix_3x3 matrix, float &x, float &y, float &z) {
   z = vector.z;
 }
 
-matrix_3x3 matrix_3x3::create_from_rows(vector_3 row_0, vector_3 row_1, vector_3 row_2) {
+matrix_3x3 matrix_3x3::create_from_rows(const vector_3 &row_0, const vector_3 &row_1, const vector_3 &row_2) {
   //row_0.debug(PSTR("row_0"));
   //row_1.debug(PSTR("row_1"));
   //row_2.debug(PSTR("row_2"));
@@ -121,10 +119,10 @@ void matrix_3x3::set_to_identity() {
   matrix[6] = 0; matrix[7] = 0; matrix[8] = 1;
 }
 
-matrix_3x3 matrix_3x3::create_look_at(vector_3 target) {
-  vector_3 z_row = target.get_normal();
-  vector_3 x_row = vector_3(1, 0, -target.x / target.z).get_normal();
-  vector_3 y_row = vector_3::cross(z_row, x_row).get_normal();
+matrix_3x3 matrix_3x3::create_look_at(const vector_3 &target) {
+  vector_3 z_row = target.get_normal(),
+           x_row = vector_3(1, 0, -target.x / target.z).get_normal(),
+           y_row = vector_3::cross(z_row, x_row).get_normal();
 
   // x_row.debug(PSTR("x_row"));
   // y_row.debug(PSTR("y_row"));
@@ -137,7 +135,7 @@ matrix_3x3 matrix_3x3::create_look_at(vector_3 target) {
   return rot;
 }
 
-matrix_3x3 matrix_3x3::transpose(matrix_3x3 original) {
+matrix_3x3 matrix_3x3::transpose(const matrix_3x3 &original) {
   matrix_3x3 new_matrix;
   new_matrix.matrix[0] = original.matrix[0]; new_matrix.matrix[1] = original.matrix[3]; new_matrix.matrix[2] = original.matrix[6];
   new_matrix.matrix[3] = original.matrix[1]; new_matrix.matrix[4] = original.matrix[4]; new_matrix.matrix[5] = original.matrix[7];
diff --git a/Marlin/src/libs/vector_3.h b/Marlin/src/libs/vector_3.h
index aed4364b91..2922ea707e 100644
--- a/Marlin/src/libs/vector_3.h
+++ b/Marlin/src/libs/vector_3.h
@@ -39,8 +39,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
-#ifndef VECTOR_3_H
-#define VECTOR_3_H
+#pragma once
 
 class matrix_3x3;
 
@@ -50,25 +49,24 @@ struct vector_3 {
   vector_3();
   vector_3(float x, float y, float z);
 
-  static vector_3 cross(vector_3 a, vector_3 b);
+  static vector_3 cross(const vector_3 &a, const vector_3 &b);
 
-  vector_3 operator+(vector_3 v);
-  vector_3 operator-(vector_3 v);
+  vector_3 operator+(const vector_3 &v);
+  vector_3 operator-(const vector_3 &v);
   void normalize();
-  float get_length();
-  vector_3 get_normal();
+  float get_length() const;
+  vector_3 get_normal() const;
 
   void debug(const char * const title);
-
-  void apply_rotation(matrix_3x3 matrix);
+  void apply_rotation(const matrix_3x3 &matrix);
 };
 
 struct matrix_3x3 {
   float matrix[9];
 
-  static matrix_3x3 create_from_rows(vector_3 row_0, vector_3 row_1, vector_3 row_2);
-  static matrix_3x3 create_look_at(vector_3 target);
-  static matrix_3x3 transpose(matrix_3x3 original);
+  static matrix_3x3 create_from_rows(const vector_3 &row_0, const vector_3 &row_1, const vector_3 &row_2);
+  static matrix_3x3 create_look_at(const vector_3 &target);
+  static matrix_3x3 transpose(const matrix_3x3 &original);
 
   void set_to_identity();
 
@@ -76,6 +74,5 @@ struct matrix_3x3 {
 };
 
 
-void apply_rotation_xyz(matrix_3x3 rotationMatrix, float &x, float &y, float &z);
+void apply_rotation_xyz(const matrix_3x3 &rotationMatrix, float &x, float &y, float &z);
 
-#endif // VECTOR_3_H