static const char * EVENT_FEATURE_STATE_REQUEST = "FeatureStateRequest";
static const char * EVENT_FEATURE_STATE_RESPONSE = "FeatureStateResponse";
+
+static const char * EVENT_UPDATE_VIEWER_BLOCKED = "UpdateViewerBlocked";
+static const char * EVENT_UPDATE_VIEWER_UNBLOCKED = "UpdateViewerUnblocked";
+
/// Message that feature was changed (used for Object Browser update): moved, updated and deleted
class MODELAPI_EXPORT ModelAPI_ObjectUpdatedMessage : public Events_MessageGroup
{