Add more constants for battle anim structs

Any access of the wram arrays for battle anim objects and background
effects use appropriate macros and constants, now.

constants/battle_anim_constants.asm

@@ -25,6 +25,7 @@
 	const BATTLEANIMSTRUCT_16
 	const BATTLEANIMSTRUCT_17
 BATTLEANIMSTRUCT_LENGTH EQU const_value
+NUM_ANIM_OBJECTS EQUS "(wActiveAnimObjectsEnd - wActiveAnimObjects) / BATTLEANIMSTRUCT_LENGTH"
 
 ; Start tile for battle animation graphics
 BATTLEANIM_BASE_TILE EQU 7 * 7  ; Maximum size of a pokemon picture
@@ -816,6 +817,8 @@ BATTLEANIM_BASE_TILE EQU 7 * 7  ; Maximum size of a pokemon picture
 	const BG_EFFECT_STRUCT_JT_INDEX
 	const BG_EFFECT_STRUCT_BATTLE_TURN
 	const BG_EFFECT_STRUCT_03
+BG_EFFECT_STRUCT_LENGTH EQU const_value
+NUM_BG_EFFECTS EQUS "(wActiveBGEffectsEnd - wActiveBGEffects) / BG_EFFECT_STRUCT_LENGTH"
 
 ; battle palettes
 	const_def

engine/battle_anims/anim_commands.asm

@@ -112,10 +112,10 @@ RunBattleAnimScript:
 	cp ROLLOUT
 	jr nz, .not_rollout
 
-	ld a, $2e
-	ld b, 5
-	ld de, 4
-	ld hl, wActiveBGEffects
+	ld a, ANIM_BG_2E
+	ld b, NUM_BG_EFFECTS
+	ld de, BG_EFFECT_STRUCT_LENGTH
+	ld hl, wBGEffect1Function
 .find
 	cp [hl]
 	jr z, .done
@@ -643,10 +643,13 @@ BattleAnimCmd_ResetObp0:
 	ret
 
 BattleAnimCmd_ClearObjs:
+; BUG: This function only clears the first 6+(2/3) objects
+
 	ld hl, wActiveAnimObjects
 	ld a, $a0
+	; ld a, wActiveAnimObjectsEnd - wActiveAnimObjects
 .loop
-	ld [hl], $0
+	ld [hl], 0
 	inc hl
 	dec a
 	jr nz, .loop
@@ -693,7 +696,7 @@ endr
 
 BattleAnimCmd_IncObj:
 	call GetBattleAnimByte
-	ld e, 10
+	ld e, NUM_ANIM_OBJECTS
 	ld bc, wActiveAnimObjects
 .loop
 	ld hl, BATTLEANIMSTRUCT_INDEX
@@ -718,8 +721,8 @@ BattleAnimCmd_IncObj:
 
 BattleAnimCmd_IncBGEffect:
 	call GetBattleAnimByte
-	ld e, 5
-	ld bc, wActiveBGEffects
+	ld e, NUM_BG_EFFECTS
+	ld bc, wBGEffect1Function
 .loop
 	ld hl, $0
 	add hl, bc
@@ -743,7 +746,7 @@ BattleAnimCmd_IncBGEffect:
 
 BattleAnimCmd_SetObj:
 	call GetBattleAnimByte
-	ld e, 10
+	ld e, NUM_ANIM_OBJECTS
 	ld bc, wActiveAnimObjects
 .loop
 	ld hl, BATTLEANIMSTRUCT_INDEX
@@ -1430,10 +1433,10 @@ BattleAnim_SetOBPals:
 	ret
 
 BattleAnim_UpdateOAM_All:
-	ld a, $0
+	ld a, 0
 	ld [wBattleAnimOAMPointerLo], a
 	ld hl, wActiveAnimObjects
-	ld e, 10
+	ld e, NUM_ANIM_OBJECTS
 .loop
 	ld a, [hl]
 	and a

engine/battle_anims/bg_effects.asm

@@ -10,7 +10,7 @@
 
 ExecuteBGEffects:
 	ld hl, wActiveBGEffects
-	ld e, 5
+	ld e, NUM_BG_EFFECTS
 .loop
 	ld a, [hl]
 	and a
@@ -23,7 +23,7 @@ ExecuteBGEffects:
 	pop de
 	pop hl
 .next
-	ld bc, 4
+	ld bc, BG_EFFECT_STRUCT_LENGTH
 	add hl, bc
 	dec e
 	jr nz, .loop
@@ -31,12 +31,12 @@ ExecuteBGEffects:
 
 QueueBGEffect:
 	ld hl, wActiveBGEffects
-	ld e, 5
+	ld e, NUM_BG_EFFECTS
 .loop
 	ld a, [hl]
 	and a
 	jr z, .load
-	ld bc, 4
+	ld bc, BG_EFFECT_STRUCT_LENGTH
 	add hl, bc
 	dec e
 	jr nz, .loop

engine/battle_anims/core.asm

@@ -1,6 +1,6 @@
 QueueBattleAnimation:
 	ld hl, wActiveAnimObjects
-	ld e, 10
+	ld e, NUM_ANIM_OBJECTS
 .loop
 	ld a, [hl]
 	and a