The base class for all constraint datas. The base class for all constraint datas. The constraint's name, which is unique across all constraints in the skeleton of the same type. The ordinal of this constraint for the order a skeleton's constraints will be applied by [code]Skeleton.update_world_transform[/code]. When true, [code]Skeleton.update_world_transform[/code] only updates this constraint if the active skin contains this constraint.