Replace Vector3.to_diagonal_matrix with Basis.from_scale

core/math/basis.cpp

@@ -207,6 +207,10 @@ Basis Basis::transposed() const {
 	return tr;
 }
 
+Basis Basis::from_scale(const Vector3 &p_scale) {
+	return Basis(p_scale.x, 0, 0, 0, p_scale.y, 0, 0, 0, p_scale.z);
+}
+
 // Multiplies the matrix from left by the scaling matrix: M -> S.M
 // See the comment for Basis::rotated for further explanation.
 void Basis::scale(const Vector3 &p_scale) {
@@ -246,10 +250,7 @@ void Basis::make_scale_uniform() {
 }
 
 Basis Basis::scaled_local(const Vector3 &p_scale) const {
-	Basis b;
-	b.set_diagonal(p_scale);
-
-	return (*this) * b;
+	return (*this) * Basis::from_scale(p_scale);
 }
 
 Vector3 Basis::get_scale_abs() const {
@@ -991,21 +992,23 @@ void Basis::set_axis_angle(const Vector3 &p_axis, real_t p_phi) {
 }
 
 void Basis::set_axis_angle_scale(const Vector3 &p_axis, real_t p_phi, const Vector3 &p_scale) {
-	set_diagonal(p_scale);
+	_set_diagonal(p_scale);
 	rotate(p_axis, p_phi);
 }
 
 void Basis::set_euler_scale(const Vector3 &p_euler, const Vector3 &p_scale) {
-	set_diagonal(p_scale);
+	_set_diagonal(p_scale);
 	rotate(p_euler);
 }
 
 void Basis::set_quaternion_scale(const Quaternion &p_quaternion, const Vector3 &p_scale) {
-	set_diagonal(p_scale);
+	_set_diagonal(p_scale);
 	rotate(p_quaternion);
 }
 
-void Basis::set_diagonal(const Vector3 &p_diag) {
+// This also sets the non-diagonal elements to 0, which is misleading from the
+// name, so we want this method to be private. Use `from_scale` externally.
+void Basis::_set_diagonal(const Vector3 &p_diag) {
 	elements[0][0] = p_diag.x;
 	elements[0][1] = 0;
 	elements[0][2] = 0;

core/math/basis.h

@@ -35,6 +35,9 @@
 #include "core/math/vector3.h"
 
 class Basis {
+private:
+	void _set_diagonal(const Vector3 &p_diag);
+
 public:
 	Vector3 elements[3] = {
 		Vector3(1, 0, 0),
@@ -166,8 +169,6 @@ public:
 	int get_orthogonal_index() const;
 	void set_orthogonal_index(int p_index);
 
-	void set_diagonal(const Vector3 &p_diag);
-
 	bool is_orthogonal() const;
 	bool is_diagonal() const;
 	bool is_rotation() const;
@@ -254,6 +255,7 @@ public:
 
 	Basis(const Vector3 &p_axis, real_t p_phi) { set_axis_angle(p_axis, p_phi); }
 	Basis(const Vector3 &p_axis, real_t p_phi, const Vector3 &p_scale) { set_axis_angle_scale(p_axis, p_phi, p_scale); }
+	static Basis from_scale(const Vector3 &p_scale);
 
 	_FORCE_INLINE_ Basis(const Vector3 &row0, const Vector3 &row1, const Vector3 &row2) {
 		elements[0] = row0;

core/math/vector3.cpp

@@ -115,12 +115,6 @@ Basis Vector3::outer(const Vector3 &p_b) const {
 	return Basis(row0, row1, row2);
 }
 
-Basis Vector3::to_diagonal_matrix() const {
-	return Basis(x, 0, 0,
-			0, y, 0,
-			0, 0, z);
-}
-
 bool Vector3::is_equal_approx(const Vector3 &p_v) const {
 	return Math::is_equal_approx(x, p_v.x) && Math::is_equal_approx(y, p_v.y) && Math::is_equal_approx(z, p_v.z);
 }

core/math/vector3.h

@@ -106,7 +106,6 @@ struct Vector3 {
 	_FORCE_INLINE_ Vector3 cross(const Vector3 &p_b) const;
 	_FORCE_INLINE_ real_t dot(const Vector3 &p_b) const;
 	Basis outer(const Vector3 &p_b) const;
-	Basis to_diagonal_matrix() const;
 
 	_FORCE_INLINE_ Vector3 abs() const;
 	_FORCE_INLINE_ Vector3 floor() const;

core/variant/variant_call.cpp

@@ -1568,7 +1568,6 @@ static void _register_variant_builtin_methods() {
 	bind_method(Vector3, dot, sarray("with"), varray());
 	bind_method(Vector3, cross, sarray("with"), varray());
 	bind_method(Vector3, outer, sarray("with"), varray());
-	bind_method(Vector3, to_diagonal_matrix, sarray(), varray());
 	bind_method(Vector3, abs, sarray(), varray());
 	bind_method(Vector3, floor, sarray(), varray());
 	bind_method(Vector3, ceil, sarray(), varray());
@@ -1732,6 +1731,7 @@ static void _register_variant_builtin_methods() {
 	bind_method(Basis, is_equal_approx, sarray("b"), varray());
 	bind_method(Basis, get_rotation_quaternion, sarray(), varray());
 	bind_static_method(Basis, looking_at, sarray("target", "up"), varray(Vector3(0, 1, 0)));
+	bind_static_method(Basis, from_scale, sarray("scale"), varray());
 
 	/* AABB */
 

doc/classes/Basis.xml

@@ -71,6 +71,13 @@
 				A negative determinant means the basis has a negative scale. A zero determinant means the basis isn't invertible, and is usually considered invalid.
 			</description>
 		</method>
+		<method name="from_scale" qualifiers="static">
+			<return type="Basis" />
+			<argument index="0" name="scale" type="Vector3" />
+			<description>
+				Constructs a pure scale basis matrix with no rotation or shearing. The scale values are set as the diagonal of the matrix, and the other parts of the matrix are zero.
+			</description>
+		</method>
 		<method name="get_euler" qualifiers="const">
 			<return type="Vector3" />
 			<description>

doc/classes/Vector3.xml

@@ -412,13 +412,6 @@
 				Returns this vector with each component snapped to the nearest multiple of [code]step[/code]. This can also be used to round to an arbitrary number of decimals.
 			</description>
 		</method>
-		<method name="to_diagonal_matrix" qualifiers="const">
-			<return type="Basis" />
-			<description>
-				Returns a diagonal matrix with the vector as main diagonal.
-				This is equivalent to a Basis with no rotation or shearing and this vector's components set as the scale.
-			</description>
-		</method>
 	</methods>
 	<members>
 		<member name="x" type="float" setter="" getter="" default="0.0">

servers/physics_3d/body_3d_sw.cpp

@@ -110,7 +110,7 @@ void Body3DSW::update_mass_properties() {
 
 					real_t mass = area * this->mass / total_area;
 
-					Basis shape_inertia_tensor = shape->get_moment_of_inertia(mass).to_diagonal_matrix();
+					Basis shape_inertia_tensor = Basis::from_scale(shape->get_moment_of_inertia(mass));
 					Transform3D shape_transform = get_shape_transform(i);
 					Basis shape_basis = shape_transform.basis.orthonormalized();
 
@@ -123,7 +123,7 @@ void Body3DSW::update_mass_properties() {
 
 				// Set the inertia to a valid value when there are no valid shapes.
 				if (!inertia_set) {
-					inertia_tensor.set_diagonal(Vector3(1.0, 1.0, 1.0));
+					inertia_tensor = Basis();
 				}
 
 				// Handle partial custom inertia.
@@ -215,7 +215,7 @@ void Body3DSW::set_param(PhysicsServer3D::BodyParameter p_param, const Variant &
 			} else {
 				calculate_inertia = false;
 				if (mode == PhysicsServer3D::BODY_MODE_DYNAMIC) {
-					principal_inertia_axes_local.set_diagonal(Vector3(1.0, 1.0, 1.0));
+					principal_inertia_axes_local = Basis();
 					_inv_inertia = inertia.inverse();
 					_update_transform_dependant();
 				}
@@ -301,7 +301,7 @@ void Body3DSW::set_mode(PhysicsServer3D::BodyMode p_mode) {
 		case PhysicsServer3D::BODY_MODE_DYNAMIC: {
 			_inv_mass = mass > 0 ? (1.0 / mass) : 0;
 			if (!calculate_inertia) {
-				principal_inertia_axes_local.set_diagonal(Vector3(1.0, 1.0, 1.0));
+				principal_inertia_axes_local = Basis();
 				_inv_inertia = inertia.inverse();
 				_update_transform_dependant();
 			}