SkeletonIK is used to place the end bone of a [Skeleton] bone chain at a certain point in 3D by rotating all bones in the chain accordingly. A typical scenario for IK in games is to place a characters feet on the ground or a characters hands on a currently hold object. SkeletonIK uses FabrikInverseKinematic internally to solve the bone chain and applies the results to the [Skeleton] [code]bones_global_pose_override[/code] property for all affected bones in the chain. If fully applied this overwrites any bone transform from [Animation]s or bone custom poses set by users. The applied amount can be controlled with the [code]interpolation[/code] property.
[codeblock]
# Apply IK effect automatically on every new frame (not the current)
skeleton_ik_node.start()
# Apply IK effect only on the current frame
skeleton_ik_node.start(true)
# Stop IK effect and reset bones_global_pose_override on Skeleton
skeleton_ik_node.stop()
# Apply full IK effect
skeleton_ik_node.set_interpolation(1.0)
# Apply half IK effect
skeleton_ik_node.set_interpolation(0.5)
# Apply zero IK effect (a value at or below 0.01 also removes bones_global_pose_override on Skeleton)
Returns the parent [Skeleton] Node that was present when SkeletonIK entered the [SceneTree]. Returns null if the parent node was not a [Skeleton] Node when SkeletonIK entered the [SceneTree].
Returns [code]true[/code] if SkeletonIK is applying IK effects on continues frames to the [Skeleton] bones. Returns [code]false[/code] if SkeletonIK is stopped or [method start] was used with the [code]one_time[/code] parameter set to [code]true[/code].
Starts applying IK effects on each frame to the [Skeleton] bones but will only take effect starting on the next frame. If [code]one_time[/code] is [code]true[/code], this will take effect immediately but also reset on the next frame.
Stops applying IK effects on each frame to the [Skeleton] bones and also calls [method Skeleton.clear_bones_global_pose_override] to remove existing overrides on all bones.
Interpolation value for how much the IK results are applied to the current skeleton bone chain. A value of [code]1.0[/code] will overwrite all skeleton bone transforms completely while a value of [code]0.0[/code] will visually disable the SkeletonIK. A value at or below [code]0.01[/code] also calls [method Skeleton.clear_bones_global_pose_override].
Secondary target position (first is [member target] property or [member target_node]) for the IK chain. Use magnet position (pole target) to control the bending of the IK chain. Only works if the bone chain has more than 2 bones. The middle chain bone position will be linearly interpolated with the magnet position.
First target of the IK chain where the tip bone is placed and, if [member override_tip_basis] is [code]true[/code], how the tip bone is rotated. If a [member target_node] path is available the nodes transform is used instead and this property is ignored.
If [code]true[/code], instructs the IK solver to consider the secondary magnet target (pole target) when calculating the bone chain. Use the magnet position (pole target) to control the bending of the IK chain.
