Restore the behavior of Spatial rotations recently changed in c1153f5.

That change was borne out of a confusion regarding the meaning of "local" in #14569.

Affine transformations in Spatial simply correspond to affine operations of its Transform. Such operations take place in a coordinate system that is defined by the parent Spatial. When there is no parent, they correspond to operations in the global coordinate system.
This coordinate system, which is relative to the parent, has been referred to as the local coordinate system in the docs so far, but this sloppy language has apparently confused some users, making them think that the local coordinate system refers to the one whose axes are "painted" on the Spatial node itself.

To avoid such conceptual conflations and misunderstandings in the future, the parent-relative local system is now referred to as "parent-local", and the object-relative local system is called "object-local" in the docs.

This commit adds the functionality "requested" in #14569, not by changing how rotate/scale/translate works, but by adding new rotate_object_local, scale_object_local and translate_object_local functions. Also, for completeness, there is now global_scale.

This commit also updates another part of the docs regarding the rotation property of Spatial, which also leads to confusion among some users.

1 files changed, 64 insertions, 28 deletions

diff --git a/scene/3d/spatial.cpp b/scene/3d/spatial.cpp
index e890533ab7..83f5df94d5 100644
--- a/scene/3d/spatial.cpp
+++ b/scene/3d/spatial.cpp
@@ -555,30 +555,36 @@ bool Spatial::is_visible() const {
 	return data.visible;
 }
 
-void Spatial::rotate(const Vector3 &p_normal, float p_radians) {
+void Spatial::rotate_object_local(const Vector3 &p_axis, float p_angle) {
+	Transform t = get_transform();
+	t.basis.rotate_local(p_axis, p_angle);
+	set_transform(t);
+}
+
+void Spatial::rotate(const Vector3 &p_axis, float p_angle) {
 
 	Transform t = get_transform();
-	t.basis.rotate_local(p_normal, p_radians); //use local rotation here, as it makes more sense here in tree hierarchy
+	t.basis.rotate(p_axis, p_angle);
 	set_transform(t);
 }
 
-void Spatial::rotate_x(float p_radians) {
+void Spatial::rotate_x(float p_angle) {
 
 	Transform t = get_transform();
-	t.basis.rotate_local(Vector3(1, 0, 0), p_radians);
+	t.basis.rotate(Vector3(1, 0, 0), p_angle);
 	set_transform(t);
 }
 
-void Spatial::rotate_y(float p_radians) {
+void Spatial::rotate_y(float p_angle) {
 
 	Transform t = get_transform();
-	t.basis.rotate_local(Vector3(0, 1, 0), p_radians);
+	t.basis.rotate(Vector3(0, 1, 0), p_angle);
 	set_transform(t);
 }
-void Spatial::rotate_z(float p_radians) {
+void Spatial::rotate_z(float p_angle) {
 
 	Transform t = get_transform();
-	t.basis.rotate_local(Vector3(0, 0, 1), p_radians);
+	t.basis.rotate(Vector3(0, 0, 1), p_angle);
 	set_transform(t);
 }
 
@@ -589,19 +595,45 @@ void Spatial::translate(const Vector3 &p_offset) {
 	set_transform(t);
 }
 
+void Spatial::translate_object_local(const Vector3 &p_offset) {
+	Transform t = get_transform();
+
+	Transform s;
+	s.translate(p_offset);
+	set_transform(t * s);
+}
+
 void Spatial::scale(const Vector3 &p_ratio) {
 
 	Transform t = get_transform();
 	t.basis.scale(p_ratio);
 	set_transform(t);
 }
-void Spatial::global_rotate(const Vector3 &p_normal, float p_radians) {
 
-	Basis rotation(p_normal, p_radians);
+void Spatial::scale_object_local(const Vector3 &p_scale) {
+	Transform t = get_transform();
+	t.basis.scale_local(p_scale);
+	set_transform(t);
+}
+
+void Spatial::global_rotate(const Vector3 &p_axis, float p_angle) {
+
+	Basis rotation(p_axis, p_angle);
 	Transform t = get_global_transform();
 	t.basis = rotation * t.basis;
 	set_global_transform(t);
 }
+
+void Spatial::global_scale(const Vector3 &p_scale) {
+
+	Basis s;
+	s.set_scale(p_scale);
+
+	Transform t = get_global_transform();
+	t.basis = s * t.basis;
+	set_global_transform(t);
+}
+
 void Spatial::global_translate(const Vector3 &p_offset) {
 	Transform t = get_global_transform();
 	t.origin += p_offset;
@@ -620,7 +652,7 @@ void Spatial::set_identity() {
 	set_transform(Transform());
 }
 
-void Spatial::look_at(const Vector3 &p_target, const Vector3 &p_up_normal) {
+void Spatial::look_at(const Vector3 &p_target, const Vector3 &p_up) {
 
 	Transform lookat;
 	lookat.origin = get_global_transform().origin;
@@ -629,19 +661,19 @@ void Spatial::look_at(const Vector3 &p_target, const Vector3 &p_up_normal) {
 		ERR_FAIL();
 	}
 
-	if (p_up_normal.cross(p_target - lookat.origin) == Vector3()) {
+	if (p_up.cross(p_target - lookat.origin) == Vector3()) {
 		ERR_EXPLAIN("Up vector and direction between node origin and target are aligned, look_at() failed");
 		ERR_FAIL();
 	}
-	lookat = lookat.looking_at(p_target, p_up_normal);
+	lookat = lookat.looking_at(p_target, p_up);
 	set_global_transform(lookat);
 }
 
-void Spatial::look_at_from_position(const Vector3 &p_pos, const Vector3 &p_target, const Vector3 &p_up_normal) {
+void Spatial::look_at_from_position(const Vector3 &p_pos, const Vector3 &p_target, const Vector3 &p_up) {
 
 	Transform lookat;
 	lookat.origin = p_pos;
-	lookat = lookat.looking_at(p_target, p_up_normal);
+	lookat = lookat.looking_at(p_target, p_up);
 	set_global_transform(lookat);
 }
 
@@ -677,9 +709,9 @@ void Spatial::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_transform"), &Spatial::get_transform);
 	ClassDB::bind_method(D_METHOD("set_translation", "translation"), &Spatial::set_translation);
 	ClassDB::bind_method(D_METHOD("get_translation"), &Spatial::get_translation);
-	ClassDB::bind_method(D_METHOD("set_rotation", "radians"), &Spatial::set_rotation);
+	ClassDB::bind_method(D_METHOD("set_rotation", "euler"), &Spatial::set_rotation);
 	ClassDB::bind_method(D_METHOD("get_rotation"), &Spatial::get_rotation);
-	ClassDB::bind_method(D_METHOD("set_rotation_degrees", "degrees"), &Spatial::set_rotation_degrees);
+	ClassDB::bind_method(D_METHOD("set_rotation_degrees", "euler_degrees"), &Spatial::set_rotation_degrees);
 	ClassDB::bind_method(D_METHOD("get_rotation_degrees"), &Spatial::get_rotation_degrees);
 	ClassDB::bind_method(D_METHOD("set_scale", "scale"), &Spatial::set_scale);
 	ClassDB::bind_method(D_METHOD("get_scale"), &Spatial::get_scale);
@@ -711,22 +743,26 @@ void Spatial::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_notify_transform", "enable"), &Spatial::set_notify_transform);
 	ClassDB::bind_method(D_METHOD("is_transform_notification_enabled"), &Spatial::is_transform_notification_enabled);
 
-	void rotate(const Vector3 &p_normal, float p_radians);
-	void rotate_x(float p_radians);
-	void rotate_y(float p_radians);
-	void rotate_z(float p_radians);
+	void rotate(const Vector3 &p_axis, float p_angle);
+	void rotate_x(float p_angle);
+	void rotate_y(float p_angle);
+	void rotate_z(float p_angle);
 	void translate(const Vector3 &p_offset);
 	void scale(const Vector3 &p_ratio);
-	void global_rotate(const Vector3 &p_normal, float p_radians);
+	void global_rotate(const Vector3 &p_axis, float p_angle);
 	void global_translate(const Vector3 &p_offset);
 
-	ClassDB::bind_method(D_METHOD("rotate", "normal", "radians"), &Spatial::rotate);
-	ClassDB::bind_method(D_METHOD("global_rotate", "normal", "radians"), &Spatial::global_rotate);
-	ClassDB::bind_method(D_METHOD("rotate_x", "radians"), &Spatial::rotate_x);
-	ClassDB::bind_method(D_METHOD("rotate_y", "radians"), &Spatial::rotate_y);
-	ClassDB::bind_method(D_METHOD("rotate_z", "radians"), &Spatial::rotate_z);
-	ClassDB::bind_method(D_METHOD("translate", "offset"), &Spatial::translate);
+	ClassDB::bind_method(D_METHOD("rotate", "axis", "angle"), &Spatial::rotate);
+	ClassDB::bind_method(D_METHOD("global_rotate", "axis", "angle"), &Spatial::global_rotate);
+	ClassDB::bind_method(D_METHOD("global_scale", "scale"), &Spatial::global_scale);
 	ClassDB::bind_method(D_METHOD("global_translate", "offset"), &Spatial::global_translate);
+	ClassDB::bind_method(D_METHOD("rotate_object_local", "axis", "angle"), &Spatial::rotate_object_local);
+	ClassDB::bind_method(D_METHOD("scale_object_local", "scale"), &Spatial::scale_object_local);
+	ClassDB::bind_method(D_METHOD("translate_object_local", "offset"), &Spatial::translate_object_local);
+	ClassDB::bind_method(D_METHOD("rotate_x", "angle"), &Spatial::rotate_x);
+	ClassDB::bind_method(D_METHOD("rotate_y", "angle"), &Spatial::rotate_y);
+	ClassDB::bind_method(D_METHOD("rotate_z", "angle"), &Spatial::rotate_z);
+	ClassDB::bind_method(D_METHOD("translate", "offset"), &Spatial::translate);
 	ClassDB::bind_method(D_METHOD("orthonormalize"), &Spatial::orthonormalize);
 	ClassDB::bind_method(D_METHOD("set_identity"), &Spatial::set_identity);