Test: Change look_at to have default up of Vector3.INF

README.md

@@ -8,6 +8,7 @@
 
 # Based on Godot 4.3 but with changes
 * [x] Expose Engine.get_frame_ticks to GDScript
+* [x] Change look_at to have default up of Vector3.INF and find appropriate axis itself if Vector3.INF is argument.
 
 # Get code
 

core/math/basis.cpp

@@ -1042,13 +1042,27 @@ void Basis::rotate_sh(real_t *p_values) {
 Basis Basis::looking_at(const Vector3 &p_target, const Vector3 &p_up, bool p_use_model_front) {
 #ifdef MATH_CHECKS
 	ERR_FAIL_COND_V_MSG(p_target.is_zero_approx(), Basis(), "The target vector can't be zero.");
-	ERR_FAIL_COND_V_MSG(p_up.is_zero_approx(), Basis(), "The up vector can't be zero.");
+	ERR_FAIL_COND_V_MSG(p_up.is_finite() && p_up.is_zero_approx(), Basis(), "The up vector can't be zero.");
 #endif
 	Vector3 v_z = p_target.normalized();
 	if (!p_use_model_front) {
 		v_z = -v_z;
 	}
-	Vector3 v_x = p_up.cross(v_z);
+
+	// Find an up vector that we can rotate around
+	Vector3 up = p_up;
+	if (! up.is_finite()) {
+		static const Vector3 up_candidates[3] = { Vector3(0, 1, 0), Vector3(1, 0, 0), Vector3(0, 0, 1) };
+		for (const Vector3 candidate : up_candidates) {
+			Vector3 v_x = candidate.cross(v_z).normalized();
+			if (! v_x.is_zero_approx()) {
+				up = candidate;
+				break;
+			}
+		}
+	}
+
+	Vector3 v_x = up.cross(v_z);
 #ifdef MATH_CHECKS
 	ERR_FAIL_COND_V_MSG(v_x.is_zero_approx(), Basis(), "The target vector and up vector can't be parallel to each other.");
 #endif

core/math/basis.h

@@ -221,7 +221,7 @@ struct [[nodiscard]] Basis {
 
 	operator Quaternion() const { return get_quaternion(); }
 
-	static Basis looking_at(const Vector3 &p_target, const Vector3 &p_up = Vector3(0, 1, 0), bool p_use_model_front = false);
+	static Basis looking_at(const Vector3 &p_target, const Vector3 &p_up = Vector3(INFINITY, INFINITY, INFINITY), bool p_use_model_front = false);
 
 	Basis(const Quaternion &p_quaternion) { set_quaternion(p_quaternion); };
 	Basis(const Quaternion &p_quaternion, const Vector3 &p_scale) { set_quaternion_scale(p_quaternion, p_scale); }

core/math/transform_3d.h

@@ -52,8 +52,8 @@ struct [[nodiscard]] Transform3D {
 	void rotate(const Vector3 &p_axis, real_t p_angle);
 	void rotate_basis(const Vector3 &p_axis, real_t p_angle);
 
-	void set_look_at(const Vector3 &p_eye, const Vector3 &p_target, const Vector3 &p_up = Vector3(0, 1, 0), bool p_use_model_front = false);
-	Transform3D looking_at(const Vector3 &p_target, const Vector3 &p_up = Vector3(0, 1, 0), bool p_use_model_front = false) const;
+	void set_look_at(const Vector3 &p_eye, const Vector3 &p_target, const Vector3 &p_up = Vector3(INFINITY, INFINITY, INFINITY), bool p_use_model_front = false);
+	Transform3D looking_at(const Vector3 &p_target, const Vector3 &p_up = Vector3(INFINITY, INFINITY, INFINITY), bool p_use_model_front = false) const;
 
 	void scale(const Vector3 &p_scale);
 	Transform3D scaled(const Vector3 &p_scale) const;

doc/classes/Basis.xml

@@ -202,12 +202,13 @@
 		<method name="looking_at" qualifiers="static">
 			<return type="Basis" />
 			<param index="0" name="target" type="Vector3" />
-			<param index="1" name="up" type="Vector3" default="Vector3(0, 1, 0)" />
+			<param index="1" name="up" type="Vector3" default="Vector3.INF" />
 			<param index="2" name="use_model_front" type="bool" default="false" />
 			<description>
 				Creates a new [Basis] with a rotation such that the forward axis (-Z) points towards the [param target] position.
 				By default, the -Z axis (camera forward) is treated as forward (implies +X is right). If [param use_model_front] is [code]true[/code], the +Z axis (asset front) is treated as forward (implies +X is left) and points toward the [param target] position.
 				The up axis (+Y) points as close to the [param up] vector as possible while staying perpendicular to the forward axis. The returned basis is orthonormalized (see [method orthonormalized]). The [param target] and [param up] vectors cannot be [constant Vector3.ZERO], and cannot be parallel to each other.
+				If the [param up] is Vector3.INF, it will use Vector3.UP, Vector3.RIGHT, or Vector3.BACK to rotate around.
 			</description>
 		</method>
 		<method name="orthonormalized" qualifiers="const">

doc/classes/Node3D.xml

@@ -114,12 +114,13 @@
 		<method name="look_at">
 			<return type="void" />
 			<param index="0" name="target" type="Vector3" />
-			<param index="1" name="up" type="Vector3" default="Vector3(0, 1, 0)" />
+			<param index="1" name="up" type="Vector3" default="Vector3.INF" />
 			<param index="2" name="use_model_front" type="bool" default="false" />
 			<description>
 				Rotates the node so that the local forward axis (-Z, [constant Vector3.FORWARD]) points toward the [param target] position.
 				The local up axis (+Y) points as close to the [param up] vector as possible while staying perpendicular to the local forward axis. The resulting transform is orthogonal, and the scale is preserved. Non-uniform scaling may not work correctly.
-				The [param target] position cannot be the same as the node's position, the [param up] vector cannot be zero, and the direction from the node's position to the [param target] vector cannot be parallel to the [param up] vector.
+				The [param target] position cannot be the same as the node's position, the [param up] vector cannot be zero, and the direction from the node's position to the [param target] vector cannot be parallel to the [param up] vector. If the
+				 [param up] is Vector3.INF, it will use Vector3.UP, Vector3.RIGHT, or Vector3.BACK to rotate around.
 				Operations take place in global space, which means that the node must be in the scene tree.
 				If [param use_model_front] is [code]true[/code], the +Z axis (asset front) is treated as forward (implies +X is left) and points toward the [param target] position. By default, the -Z axis (camera forward) is treated as forward (implies +X is right).
 			</description>
@@ -128,7 +129,7 @@
 			<return type="void" />
 			<param index="0" name="position" type="Vector3" />
 			<param index="1" name="target" type="Vector3" />
-			<param index="2" name="up" type="Vector3" default="Vector3(0, 1, 0)" />
+			<param index="2" name="up" type="Vector3" default="Vector3.INF" />
 			<param index="3" name="use_model_front" type="bool" default="false" />
 			<description>
 				Moves the node to the specified [param position], and then rotates the node to point toward the [param target] as per [method look_at]. Operations take place in global space.

doc/classes/Transform3D.xml

@@ -97,11 +97,12 @@
 		<method name="looking_at" qualifiers="const">
 			<return type="Transform3D" />
 			<param index="0" name="target" type="Vector3" />
-			<param index="1" name="up" type="Vector3" default="Vector3(0, 1, 0)" />
+			<param index="1" name="up" type="Vector3" default="Vector3.INF" />
 			<param index="2" name="use_model_front" type="bool" default="false" />
 			<description>
 				Returns a copy of this transform rotated so that the forward axis (-Z) points towards the [param target] position.
 				The up axis (+Y) points as close to the [param up] vector as possible while staying perpendicular to the forward axis. The resulting transform is orthonormalized. The existing rotation, scale, and skew information from the original transform is discarded. The [param target] and [param up] vectors cannot be zero, cannot be parallel to each other, and are defined in global/parent space.
+				If the [param up] is Vector3.INF, it will use Vector3.UP, Vector3.RIGHT, or Vector3.BACK to rotate around.
 				If [param use_model_front] is [code]true[/code], the +Z axis (asset front) is treated as forward (implies +X is left) and points toward the [param target] position. By default, the -Z axis (camera forward) is treated as forward (implies +X is right).
 			</description>
 		</method>

editor/import/3d/scene_import_settings.cpp

@@ -1735,7 +1735,7 @@ SceneImportSettingsDialog::SceneImportSettingsDialog() {
 	camera->set_environment(environment);
 
 	light1 = memnew(DirectionalLight3D);
-	light1->set_transform(Transform3D(Basis::looking_at(Vector3(-1, -1, -1))));
+	light1->set_transform(Transform3D(Basis::looking_at(Vector3(-1, -1, -1), Vector3(INFINITY, INFINITY, INFINITY))));
 	light1->set_shadow(true);
 	camera->add_child(light1);
 

editor/plugins/node_3d_editor_gizmos.cpp

@@ -655,7 +655,7 @@ bool EditorNode3DGizmo::intersect_ray(Camera3D *p_camera, const Point2 &p_point,
 		Transform3D t = spatial_node->get_global_transform();
 		Vector3 camera_position = p_camera->get_camera_transform().origin;
 		if (!camera_position.is_equal_approx(t.origin)) {
-			t.set_look_at(t.origin, camera_position);
+			t.set_look_at(t.origin, camera_position, Vector3(INFINITY, INFINITY, INFINITY));
 		}
 
 		float scale = t.origin.distance_to(p_camera->get_camera_transform().origin);
@@ -672,7 +672,7 @@ bool EditorNode3DGizmo::intersect_ray(Camera3D *p_camera, const Point2 &p_point,
 
 		if (!orig_camera_transform.origin.is_equal_approx(t.origin) &&
 				ABS(orig_camera_transform.basis.get_column(Vector3::AXIS_Z).dot(Vector3(0, 1, 0))) < 0.99) {
-			p_camera->look_at(t.origin);
+			p_camera->look_at(t.origin, Vector3(INFINITY, INFINITY, INFINITY));
 		}
 
 		Vector3 c0 = t.xform(Vector3(selectable_icon_size, selectable_icon_size, 0) * scale);

scene/3d/node_3d.cpp

@@ -1195,8 +1195,8 @@ void Node3D::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("orthonormalize"), &Node3D::orthonormalize);
 	ClassDB::bind_method(D_METHOD("set_identity"), &Node3D::set_identity);
 
-	ClassDB::bind_method(D_METHOD("look_at", "target", "up", "use_model_front"), &Node3D::look_at, DEFVAL(Vector3(0, 1, 0)), DEFVAL(false));
-	ClassDB::bind_method(D_METHOD("look_at_from_position", "position", "target", "up", "use_model_front"), &Node3D::look_at_from_position, DEFVAL(Vector3(0, 1, 0)), DEFVAL(false));
+	ClassDB::bind_method(D_METHOD("look_at", "target", "up", "use_model_front"), &Node3D::look_at, DEFVAL(Vector3(INFINITY, INFINITY, INFINITY)), DEFVAL(false));
+	ClassDB::bind_method(D_METHOD("look_at_from_position", "position", "target", "up", "use_model_front"), &Node3D::look_at_from_position, DEFVAL(Vector3(INFINITY, INFINITY, INFINITY)), DEFVAL(false));
 
 	ClassDB::bind_method(D_METHOD("to_local", "global_point"), &Node3D::to_local);
 	ClassDB::bind_method(D_METHOD("to_global", "local_point"), &Node3D::to_global);

scene/3d/node_3d.h

@@ -252,8 +252,8 @@ class Node3D : public Node {
 	void global_scale(const Vector3 &p_scale);
 	void global_translate(const Vector3 &p_offset);
 
-	void look_at(const Vector3 &p_target, const Vector3 &p_up = Vector3(0, 1, 0), bool p_use_model_front = false);
-	void look_at_from_position(const Vector3 &p_pos, const Vector3 &p_target, const Vector3 &p_up = Vector3(0, 1, 0), bool p_use_model_front = false);
+	void look_at(const Vector3 &p_target, const Vector3 &p_up = Vector3(INFINITY, INFINITY, INFINITY), bool p_use_model_front = false);
+	void look_at_from_position(const Vector3 &p_pos, const Vector3 &p_target, const Vector3 &p_up = Vector3(INFINITY, INFINITY, INFINITY), bool p_use_model_front = false);
 
 	Vector3 to_local(Vector3 p_global) const;
 	Vector3 to_global(Vector3 p_local) const;

scene/3d/path_3d.cpp

@@ -326,7 +326,7 @@ Transform3D PathFollow3D::correct_posture(Transform3D p_transform, PathFollow3D:
 		Vector3 tangent = -t.basis.get_column(2);
 
 		// Y-axis points up by default.
-		t.basis = Basis::looking_at(tangent);
+		t.basis = Basis::looking_at(tangent, Vector3(INFINITY, INFINITY, INFINITY));
 	} else {
 		// Lock some euler axes.
 		Vector3 euler = t.basis.get_euler_normalized(EulerOrder::YXZ);

tests/scene/test_camera_3d.h

@@ -143,7 +143,7 @@ TEST_CASE("[SceneTree][Camera3D] Position queries") {
 		// The orthogonal case is simpler, so we test a more random position + rotation combination here.
 		// For the other cases we'll use zero translation and rotation instead.
 		test_camera->set_global_position(Vector3(1, 2, 3));
-		test_camera->look_at(Vector3(-4, 5, 1));
+		test_camera->look_at(Vector3(-4, 5, 1), Vector3(INFINITY, INFINITY, INFINITY));
 		// Width = 5, Aspect Ratio = 400 / 200 = 2, so Height is 2.5.
 		test_camera->set_orthogonal(5.0f, 0.5f, 1000.0f);
 		const Basis basis = test_camera->get_global_basis();