+#define IS_BD_CONVEYOR_BELT(e) ((e) == EL_BD_CONVEYOR_LEFT || \
+ (e) == EL_BD_CONVEYOR_LEFT_ACTIVE || \
+ (e) == EL_BD_CONVEYOR_RIGHT || \
+ (e) == EL_BD_CONVEYOR_RIGHT_ACTIVE)
+
+#define IS_BD_CONVEYOR_BELT_SWITCH(e) ((e) == EL_BD_CONVEYOR_SWITCH || \
+ (e) == EL_BD_CONVEYOR_SWITCH_ACTIVE || \
+ (e) == EL_BD_CONVEYOR_DIR_SWITCH_NORMAL || \
+ (e) == EL_BD_CONVEYOR_DIR_SWITCH_CHANGED)
+