Use some more constants in place of raw numbers

constants/battle_constants.asm

@@ -1,15 +1,20 @@
 DEF MAX_LEVEL EQU 100
 
+; maximum moves known per mon
 DEF NUM_MOVES EQU 4
 
+; significant stat values
+DEF BASE_STAT_LEVEL EQU 7
+DEF MAX_STAT_LEVEL EQU 13
+
 ; VitaminStats indexes (see data/battle/stat_names.asm)
-	const_def
+	const_def 1
 	const STAT_HEALTH
 	const STAT_ATTACK
 	const STAT_DEFENSE
 	const STAT_SPEED
 	const STAT_SPECIAL
-DEF NUM_STATS EQU const_value
+DEF NUM_STATS EQU const_value - 1
 
 ; StatModTextStrings indexes (see data/battle/stat_mod_names.asm)
 	const_def

engine/battle/core.asm

@@ -18,7 +18,7 @@ SlidePlayerAndEnemySilhouettesOnScreen:
 	call LoadFontTilePatterns
 	call LoadHudAndHpBarAndStatusTilePatterns
 	ld hl, vBGMap0
-	ld bc, $400
+	ld bc, BG_MAP_WIDTH * BG_MAP_HEIGHT
 .clearBackgroundLoop
 	ld a, " "
 	ld [hli], a
@@ -29,9 +29,9 @@ SlidePlayerAndEnemySilhouettesOnScreen:
 ; copy the work RAM tile map to VRAM
 	hlcoord 0, 0
 	ld de, vBGMap0
-	ld b, 18 ; number of rows
+	ld b, SCREEN_HEIGHT
 .copyRowLoop
-	ld c, 20 ; number of columns
+	ld c, SCREEN_WIDTH
 .copyColumnLoop
 	ld a, [hli]
 	ld [de], a
@@ -825,7 +825,7 @@ FaintEnemyPokemon:
 ; the enemy mon base stats are added to stat exp, so they are halved
 ; the base exp (which determines normal exp) is also halved
 	ld hl, wEnemyMonBaseStats
-	ld b, $7
+	ld b, NUM_STATS + 2
 .halveExpDataLoop
 	srl [hl]
 	inc hl
@@ -1259,7 +1259,7 @@ SlideTrainerPicOffScreen:
 	dec c
 	jr nz, .columnLoop
 	pop hl
-	ld de, 20
+	ld de, SCREEN_WIDTH
 	add hl, de
 	dec b
 	jr nz, .rowLoop
@@ -4183,7 +4183,7 @@ GetDamageVarsForPlayerAttack:
 	and a ; check for critical hit
 	jr z, .scaleStats
 ; in the case of a critical hit, reset the player's attack and the enemy's defense to their base values
-	ld c, 3 ; defense stat
+	ld c, STAT_DEFENSE
 	call GetEnemyMonStat
 	ldh a, [hProduct + 2]
 	ld b, a
@@ -4215,7 +4215,7 @@ GetDamageVarsForPlayerAttack:
 	and a ; check for critical hit
 	jr z, .scaleStats
 ; in the case of a critical hit, reset the player's and enemy's specials to their base values
-	ld c, 5 ; special stat
+	ld c, STAT_SPECIAL
 	call GetEnemyMonStat
 	ldh a, [hProduct + 2]
 	ld b, a
@@ -4304,7 +4304,7 @@ GetDamageVarsForEnemyAttack:
 	ld b, a
 	ld c, [hl]
 	push bc
-	ld c, 2 ; attack stat
+	ld c, STAT_ATTACK
 	call GetEnemyMonStat
 	ld hl, hProduct + 2
 	pop bc
@@ -4336,7 +4336,7 @@ GetDamageVarsForEnemyAttack:
 	ld b, a
 	ld c, [hl]
 	push bc
-	ld c, 5 ; special stat
+	ld c, STAT_SPECIAL
 	call GetEnemyMonStat
 	ld hl, hProduct + 2
 	pop bc
@@ -4380,7 +4380,7 @@ GetDamageVarsForEnemyAttack:
 	ret
 
 ; get stat c of enemy mon
-; c: stat to get (HP=1,Attack=2,Defense=3,Speed=4,Special=5)
+; c: stat to get (STAT_* constant)
 GetEnemyMonStat:
 	push de
 	push bc
@@ -5287,7 +5287,7 @@ AdjustDamageForMoveType:
 	call Multiply
 	ld a, 10
 	ldh [hDivisor], a
-	ld b, $04
+	ld b, 4
 	call Divide
 	ldh a, [hQuotient + 2]
 	ld [hli], a
@@ -5315,7 +5315,6 @@ AdjustDamageForMoveType:
 ; this doesn't take into account the effects that dual types can have
 ; (e.g. 4x weakness / resistance, weaknesses and resistances canceling)
 ; the result is stored in [wTypeEffectiveness]
-; ($05 is not very effective, $10 is neutral, $14 is super effective)
 ; as far is can tell, this is only used once in some AI code to help decide which move to use
 AIGetTypeEffectiveness:
 	ld a, [wEnemyMoveType]
@@ -5324,8 +5323,10 @@ AIGetTypeEffectiveness:
 	ld b, [hl]                 ; b = type 1 of player's pokemon
 	inc hl
 	ld c, [hl]                 ; c = type 2 of player's pokemon
-	ld a, $10
+	; initialize to neutral effectiveness
-	ld [wTypeEffectiveness], a ; initialize to neutral effectiveness
+	; bug: this is $10 (MORE_EFFECTIVE + 1) but should be 10 (EFFECTIVE)
+	ld a, MORE_EFFECTIVE + 1
+	ld [wTypeEffectiveness], a
 	ld hl, TypeEffects
 .loop
 	ld a, [hli]
@@ -6909,7 +6910,6 @@ _InitBattleCommon:
 	db "@"
 
 _LoadTrainerPic:
-; wd033-wd034 contain pointer to pic
 	ld a, [wTrainerPicPointer]
 	ld e, a
 	ld a, [wTrainerPicPointer + 1]
@@ -7043,7 +7043,7 @@ LoadMonBackPic:
 	call InterlaceMergeSpriteBuffers ; combine the two buffers to a single 2bpp sprite
 	ld hl, vSprites
 	ld de, vBackPic
-	ld c, (2*SPRITEBUFFERSIZE)/16 ; count of 16-byte chunks to be copied
+	ld c, (2 * SPRITEBUFFERSIZE) / 16 ; count of 16-byte chunks to be copied
 	ldh a, [hLoadedROMBank]
 	ld b, a
 	jp CopyVideoData