Rename CheckTrainerBattle

Renamed to be more in line with our current coding standards. Hopefully
this is slightly more readable.

engine/overworld/events.asm

@@ -248,7 +248,7 @@ PlayerEvents:
 
 	call Dummy_CheckScriptFlags3Bit5 ; This is a waste of time
 
-	call CheckTrainerBattle3
+	call CheckTrainerBattle_GetPlayerEvent
 	jr c, .ok
 
 	call CheckTileEvent
@@ -289,10 +289,10 @@ PlayerEvents:
 	scf
 	ret
 
-CheckTrainerBattle3:
+CheckTrainerBattle_GetPlayerEvent:
 	nop
 	nop
-	call CheckTrainerBattle2
+	call CheckTrainerBattle
 	jr nc, .nope
 
 	ld a, PLAYEREVENT_SEENBYTRAINER

home/flag.asm

@@ -38,7 +38,7 @@ FlagAction::
 ;    1  SET_FLAG    set bit
 ;    2  CHECK_FLAG  check bit
 ; de: bit number
-; hl: index within bit table
+; hl: pointer to the flag array
 
 	; get index within the byte
 	ld a, e

home/trainers.asm

@@ -1,16 +1,16 @@
-CheckTrainerBattle2::
+CheckTrainerBattle::
 	ldh a, [hROMBank]
 	push af
 
 	call SwitchToMapScriptsBank
-	call CheckTrainerBattle
+	call _CheckTrainerBattle
 
 	pop bc
 	ld a, b
 	rst Bankswitch
 	ret
 
-CheckTrainerBattle::
+_CheckTrainerBattle::
 ; Check if any trainer on the map sees the player and wants to battle.
 
 ; Skip the player object.
@@ -35,7 +35,7 @@ CheckTrainerBattle::
 	add hl, de
 	ld a, [hl]
 	and $f
-	cp $2
+	cp OBJECTTYPE_TRAINER
 	jr nz, .next
 
 ; Is visible on the map

hram.asm

@@ -126,9 +126,7 @@ hWY::            db ; ffd2
 hTilesPerCycle:: db ; ffd3
 hBGMapMode::     db ; ffd4
 hBGMapThird::    db ; ffd5
-hBGMapAddress::  db ; ffd6
-
-	ds 1
+hBGMapAddress::  dw ; ffd6
 
 hOAMUpdate:: db ; ffd8