Identify more bit flags (#1153)

engine/events/battle_tower/battle_tower.asm

@@ -219,7 +219,7 @@ RunBattleTowerTrainer:
 
 	ld a, [wInBattleTowerBattle]
 	push af
-	or 1
+	or 1 << IN_BATTLE_TOWER_BATTLE_F
 	ld [wInBattleTowerBattle], a
 
 	xor a

engine/events/field_moves.asm

@@ -234,17 +234,21 @@ Cut_SpawnLeaf:
 	pop de
 	ret
 
+; cut leaf spawn coords table bits
+DEF CUT_LEAF_SPAWN_RIGHT_F  EQU 0
+DEF CUT_LEAF_SPAWN_BOTTOM_F EQU 1
+
 Cut_GetLeafSpawnCoords:
 	ld de, 0
 	ld a, [wPlayerMetatileX]
-	bit 0, a
+	bit 0, a ; even or odd?
 	jr z, .left_side
-	set 0, e
+	set CUT_LEAF_SPAWN_RIGHT_F, e
 .left_side
 	ld a, [wPlayerMetatileY]
-	bit 0, a
+	bit 0, a ; even or odd?
 	jr z, .top_side
-	set 1, e
+	set CUT_LEAF_SPAWN_BOTTOM_F, e
 .top_side
 	ld a, [wPlayerDirection]
 	and %00001100

engine/events/map_name_sign.asm

@@ -26,9 +26,9 @@ InitMapNameSign::
 	ld [wCurLandmark], a
 
 .not_gate
-	ld hl, wEnteredMapFromContinue
-	bit 1, [hl]
-	res 1, [hl]
+	ld hl, wMapNameSignFlags
+	bit SHOWN_MAP_NAME_SIGN, [hl]
+	res SHOWN_MAP_NAME_SIGN, [hl]
 	jr nz, .dont_do_map_sign
 
 	call .CheckMovingWithinLandmark

engine/events/mom.asm

@@ -284,7 +284,7 @@ BankOfMom:
 DSTChecks:
 ; check the time; avoid changing DST if doing so would change the current day
 	ld a, [wDST]
-	bit 7, a
+	bit DST_F, a
 	ldh a, [hHours]
 	jr z, .NotDST
 	and a ; within one hour of 00:00?
@@ -313,14 +313,14 @@ DSTChecks:
 	call .ClearBox
 	bccoord 1, 14
 	ld a, [wDST]
-	bit 7, a
+	bit DST_F, a
 	jr z, .SetDST
 	ld hl, .TimesetAskNotDSTText
 	call PrintTextboxTextAt
 	call YesNoBox
 	ret c
 	ld a, [wDST]
-	res 7, a
+	res DST_F, a
 	ld [wDST], a
 	call .SetClockBack
 	call .ClearBox
@@ -335,7 +335,7 @@ DSTChecks:
 	call YesNoBox
 	ret c
 	ld a, [wDST]
-	set 7, a
+	set DST_F, a
 	ld [wDST], a
 	call .SetClockForward
 	call .ClearBox