X-Git-Url: http://git.purplebirdman.com/william-skin.git/blobdiff_plain/c84055968443414e67caa33c3a823094ed29365b..HEAD:/TrackingBone3D_head.gd

diff --git a/TrackingBone3D_head.gd b/TrackingBone3D_head.gd
index 04e6938..6d522b3 100644
--- a/TrackingBone3D_head.gd
+++ b/TrackingBone3D_head.gd
@@ -4,8 +4,14 @@ class_name TrackingBone3D_head
 extends SkeletonModifier3D
 
 @export_enum(" ") var bone: String
-@export var target: Vector3 = Vector3(0, 0, 0)
+@export var target: Node3D = null
+@export var influence_lerp_seconds: float = 0.5
+@export var rotation_lerp_weight: float = 0.5
 
+var _skeleton: Skeleton3D
+var _bone_idx: int
+
+var old_current_pose: Transform3D = Transform3D.IDENTITY
 
 func _validate_property(property: Dictionary) -> void:
 	if property.name == "bone":
@@ -15,23 +21,58 @@ func _validate_property(property: Dictionary) -> void:
 			property.hint_string = skeleton.get_concatenated_bone_names()
 
 
+func _ready() -> void:
+	# for tweening influence
+	influence = 0
+	
+	# for tweening bone poses
+	_skeleton = get_skeleton()
+	if not _skeleton:
+		push_error("Expected a skeleton!")
+	_bone_idx = _skeleton.find_bone(bone)
+	
+	# for smooth rotations
+	old_current_pose = _skeleton.global_transform * _skeleton.get_bone_global_pose(_bone_idx)
+
+
+func tween_influence(goal_weight: float) -> void:
+	create_tween().tween_method(
+		_interpolate_influence, influence, goal_weight, influence_lerp_seconds
+		).set_trans(Tween.TRANS_EXPO)
+
+
+func _interpolate_influence(weight: float) -> void:
+	influence = weight
+
+
+
 func _process_modification() -> void:
-	var skeleton: Skeleton3D = get_skeleton()
-	if !skeleton:
-		return # Never happen, but for the safety.
-	var bone_idx: int = skeleton.find_bone(bone)
-	var _parent_idx: int = skeleton.get_bone_parent(bone_idx)
-	var pose: Transform3D = skeleton.global_transform * skeleton.get_bone_global_pose(bone_idx)
+	if target == null:
+		return
+
+	var current_pose: Transform3D = _skeleton.global_transform * _skeleton.get_bone_global_pose(_bone_idx)
+	current_pose.basis = old_current_pose.basis
+	var target_pose: Transform3D  = current_pose.looking_at(target.global_position, Vector3.UP)
+	
+	# TODO: replace this specific code with general purpose modifier
+	var axis: Vector3 = target_pose.basis.y
+	target_pose = target_pose.rotated(axis, PI)
+	
+	# https://docs.godotengine.org/en/latest/tutorials/3d/using_transforms.html#interpolating-with-quaternions
+	if rotation_lerp_weight > 0:
+		var from := Quaternion(current_pose.basis.orthonormalized())
+		var to := Quaternion(target_pose.basis.orthonormalized())
+		var rot_target := from.slerp(to, rotation_lerp_weight)
+		target_pose.basis = Basis(rot_target)
 	
-	#var looked_at: Transform3D = _w_look_at(pose, target)
-	var looked_at: Transform3D = pose.looking_at(target, Vector3.UP)
-	var axis: Vector3 = looked_at.basis.y
-	looked_at = looked_at.rotated(axis, PI)
+	# remember this!
+	old_current_pose = target_pose
 	
-	skeleton.set_bone_global_pose(
-		bone_idx,
+	# yield until target pose has changed, then apply it?
+	_skeleton.set_bone_global_pose(
+		_bone_idx,
 		Transform3D(
-			(skeleton.global_transform.affine_inverse() * looked_at).basis.orthonormalized(), 
-			skeleton.get_bone_global_pose(bone_idx).origin
+			(_skeleton.global_transform.affine_inverse() * target_pose).basis.orthonormalized(), 
+			_skeleton.get_bone_global_pose(_bone_idx).origin
 			)
 		)