protected void OffsetGUI(SplinePrimitive primitive)
 {
     primitive.offset = EditorGUILayout.Vector3Field("Offset", primitive.offset);
 }
 protected void RotationGUI(SplinePrimitive primitive)
 {
     primitive.rotation = EditorGUILayout.Vector3Field("Rotation", primitive.rotation);
 }
 protected void AxisGUI(SplinePrimitive primitive)
 {
     primitive.axis = (SplinePrimitive.Axis)EditorGUILayout.EnumPopup("Axis", primitive.axis);
 }