The [AimModifier3D] rotates a bone to look at a reference bone. This is a simple version of [LookAtModifier3D] that only allows bone to the reference without advanced options such as angle limitation or time-based interpolation. The feature is simplified, but instead it is implemented with smooth tracking without euler, see [method set_use_euler]. Returns the forward axis of the bone. Returns the axis of the first rotation. It is enabled only if [method is_using_euler] is [code]true[/code]. Returns [code]true[/code] if it provides rotation with using euler. Returns [code]true[/code] if it provides rotation by two axes. It is enabled only if [method is_using_euler] is [code]true[/code]. Sets the forward axis of the bone. Sets the axis of the first rotation. It is enabled only if [method is_using_euler] is [code]true[/code]. If sets [param enabled] to [code]true[/code], it provides rotation with using euler. If sets [param enabled] to [code]false[/code], it provides rotation with using rotation by arc generated from the forward axis vector and the vector toward the reference. If sets [param enabled] to [code]true[/code], it provides rotation by two axes. It is enabled only if [method is_using_euler] is [code]true[/code]. The number of settings in the modifier.