AI Improvements

This fixes some of the issues with the current AI system to make them better. In short:

- Most Trainers should correctly recognise when a move is not very effective, and not use it. If they have a supereffective move and a regular-effective move, they will slightly prioritise the supereffective one, but not always use it like in regular RBY. This prevents the Lorelei softlock, for example.

- Trainers won't attempt to set status effects on Pokemon that already have one, won't try recovering at full health, and won't attempt to set up multiple Reflects or Light Screen

- Certain high-level trainers will recognise when a Pokemon does not have a status, and will try to inflict one if so. This makes Agatha's, Erika's and Koga's team types much more effective.

- Youngsters and Cue Balls no longer pick moves randomly and will actually give it some thought

- Brock and the Engineers now recognize type effectiveness, Students do not given how early they're encountered.

- General improvements to move choices for all Gym Leaders, E4 and Shinjuku Jacky.

We're almost done.

README.md

@@ -260,7 +260,7 @@ and more!
 
 Known Bugs
 ====
-- The new AI (possibly bugged?) behaves quite oddly, such as using Recover at full HP, spamming status-inflicting moves like Lovely Kiss, neglecting supereffective moves, setting up multiple Reflects, etc.
+- Currently testing...
 
 Evolution Methods for new Pokemon
 ====

data/predef_pointers.asm

@@ -50,7 +50,7 @@ PredefPointers::
 	add_predef UpdateHPBar
 	add_predef HPBarLength
 	add_predef Diploma_TextBoxBorder
-;	add_predef DoubleOrHalveSelectedStats
+	add_predef DoubleOrHalveSelectedStats
 	add_predef ShowPokedexMenu
 	add_predef EvolutionAfterBattle
 	add_predef SaveSAVtoSRAM0

data/trainers/move_choices.asm

@@ -9,7 +9,7 @@ ENDM
 ; move choice modification methods that are applied for each trainer class
 TrainerClassMoveChoiceModifications:
 	list_start TrainerClassMoveChoiceModifications
-	move_choices         ; YOUNGSTER
+	move_choices 1       ; YOUNGSTER
 	move_choices 1       ; BUG CATCHER
 	move_choices 1       ; LASS
 	move_choices 1, 3    ; SAILOR
@@ -20,10 +20,10 @@ TrainerClassMoveChoiceModifications:
 	move_choices 1       ; HIKER
 	move_choices 1       ; BIKER
 	move_choices 1, 3    ; BURGLAR
-	move_choices 1       ; ENGINEER
+	move_choices 1, 3    ; ENGINEER
 	move_choices 1, 3    ; FISHER
 	move_choices 1, 3    ; SWIMMER
-	move_choices         ; CUE_BALL
+	move_choices 1       ; CUE_BALL
 	move_choices 1       ; GAMBLER
 	move_choices 1, 3    ; BEAUTY
 	move_choices 1, 2    ; PSYCHIC_TR
@@ -33,32 +33,32 @@ TrainerClassMoveChoiceModifications:
 	move_choices 1       ; BIRD_KEEPER
 	move_choices 1       ; BLACKBELT
 	move_choices 1       ; RIVAL1
-	move_choices 1, 3    ; PROF_OAK
+	move_choices 1, 2, 3, 4 ; PROF_OAK
-	move_choices 1, 2    ; CHIEF
+	move_choices 1, 2, 3, 4 ; CHIEF
-	move_choices 1, 2    ; SCIENTIST
+	move_choices 1, 2, 4 ; SCIENTIST
-	move_choices 1, 3    ; GIOVANNI
+	move_choices 1, 2, 3 ; GIOVANNI
 	move_choices 1       ; ROCKET
-	move_choices 1, 3    ; COOLTRAINER_M
+	move_choices 1, 3, 4 ; COOLTRAINER_M
-	move_choices 1, 3    ; COOLTRAINER_F
+	move_choices 1, 3, 4 ; COOLTRAINER_F
-	move_choices 1       ; BRUNO
+	move_choices 1, 2, 3 ; BRUNO
-	move_choices 1       ; BROCK
+	move_choices 1, 3    ; BROCK
-	move_choices 1, 3    ; MISTY
+	move_choices 1, 3, 4 ; MISTY
-	move_choices 1, 3    ; LT_SURGE
+	move_choices 1, 2, 3 ; LT_SURGE
-	move_choices 1, 3    ; ERIKA
+	move_choices 1, 3, 4 ; ERIKA
-	move_choices 1, 3    ; KOGA
+	move_choices 1, 3, 4 ; KOGA
-	move_choices 1, 3    ; BLAINE
+	move_choices 1, 2, 3 ; BLAINE
-	move_choices 1, 3    ; SABRINA
+	move_choices 1, 3, 4 ; SABRINA
 	move_choices 1, 2    ; GENTLEMAN
 	move_choices 1, 3    ; RIVAL2
-	move_choices 1, 3    ; RIVAL3
+	move_choices 1, 2, 3, 4 ; RIVAL3
-	move_choices 1, 2, 3 ; LORELEI
+	move_choices 1, 2, 3, 4 ; LORELEI
 	move_choices 1       ; CHANNELER
-	move_choices 1       ; AGATHA
+	move_choices 1, 2, 3, 4 ; AGATHA
-	move_choices 1, 3    ; LANCE
+	move_choices 1, 2, 3, 4 ; LANCE
-	move_choices 1, 3,   ; YUJIROU, was UNUSED_JUGGLER
+	move_choices 1, 3,   ; YUJIROU
-	move_choices 1, 3,   ; STUDENT
+	move_choices 1       ; STUDENT
 	move_choices 1, 3,   ; FIREFIGHTER
-	move_choices 1, 3,   ; KOICHI
+	move_choices 1, 2, 3 ; KOICHI
-	move_choices 1, 3,   ; JACK
+	move_choices 1, 2, 3, 4 ; JACK
 	move_choices 1, 3,   ; JESSIE_JAMES
 	assert_list_length NUM_TRAINERS

engine/battle/trainer_ai.asm

@@ -7,6 +7,18 @@ AIEnemyTrainerChooseMoves:
 	ld [hli], a   ; move 2
 	ld [hli], a   ; move 3
 	ld [hl], a    ; move 4
+	
+;;;;;;;;;; shinpokerednote: ADDED: make a backup buffer
+	push hl
+	ld a, $ff
+	inc hl
+	ld [hli], a	;backup 1
+	ld [hli], a	;backup 2
+	ld [hli], a	;backup 3
+	ld [hl], a	;backup 4
+	pop hl
+;;;;;;;;;;
+
 	ld a, [wEnemyDisabledMove] ; forbid disabled move (if any)
 	swap a
 	and $f
@@ -52,6 +64,11 @@ AIEnemyTrainerChooseMoves:
 	ld de, .nextMoveChoiceModification  ; set return address
 	push de
 	jp hl         ; execute modification function
+.loopFindMinimumEntries_backupfirst	;shinpokerednote: ADDED: make a backup of the scores
+	ld hl, wBuffer  ; temp move selection array
+	ld de, wBuffer + NUM_MOVES  ;backup buffer
+	ld bc, NUM_MOVES
+	rst _CopyData
 .loopFindMinimumEntries ; all entries will be decremented sequentially until one of them is zero
 	ld hl, wBuffer  ; temp move selection array
 	ld de, wEnemyMonMoves  ; enemy moves
@@ -466,10 +483,8 @@ AIMoveChoiceModification3:
 	jr c, .notEffectiveMove
 	;ld a, [wEnemyMoveEffect]
 	; check for reasons not to use a super effective move here
-
 	dec [hl] ; slightly encourage this super effective move
 .checkSpecificEffects ; we'll further encourage certain moves
-	call EncouragePriorityIfSlow
 	call EncourageDrainingMoveIfLowHealth
 	jr .nextMove
 .notEffectiveMove ; discourages non-effective moves if better moves are available
@@ -479,7 +494,7 @@ AIMoveChoiceModification3:
 	ld a, [wEnemyMoveType]
 	ld d, a
 	ld hl, wEnemyMonMoves  ; enemy moves
-	ld b, NUM_MOVES + 1
+	ld bc, NUM_MOVES + 1
 	ld c, $0
 .loopMoves
 	dec b
@@ -543,18 +558,6 @@ CompareSpeed:
 	ret
 ;;;;;;;;;;
 
-; PureRGBnote: ADDED: encourages priority moves if the enemy's pokemon is slower than the player's and the move is neutral or super effective.
-; BUT this effect is only applied after you have the soulbadge to prevent priority moves from being spammed early game.
-; Applies to trainers that use AI subroutine 3
-EncouragePriorityIfSlow:
-	ld a, [wObtainedBadges]
-	bit BIT_SOULBADGE, a
-	ret z
-	call CompareSpeed
-	ret nc
-	dec [hl] ; encourage the move if it's a priority move and the pokemon is slower
-	ret
-
 ; PureRGBnote: ADDED: if the opponent has less than 1/2 health they will prefer healing moves if they use AI subroutine 3
 EncourageDrainingMoveIfLowHealth:
 	ld a, [wEnemyMoveEffect]
@@ -576,11 +579,11 @@ AIMoveChoiceModification4:
 	ld b, NUM_MOVES + 1
 .nextMove
 	dec b
-	jr z, .done ; processed all 4 moves
+	ret z ; processed all 4 moves
 	inc hl
 	ld a, [de]
 	and a
-	jr z, .done ; no more moves in move set
+	ret z ; no more moves in move set
 	inc de
 	call ReadMove
 	ld a, [wEnemyMoveEffect]
@@ -626,8 +629,7 @@ AIMoveChoiceModification4:
 	jr z, .nextMove ; if the AI thinks the player IS NOT asleep before they switch, we shouldn't encourage based on the new mon's status
 	ld a, [wBattleMonStatus]
 	and SLP_MASK
-	jr nz, .preferMoveEvenMore ; heavier favor for dream eater if the opponent is asleep
+	jr z, .nextMove
-	jr .nextMove
 .preferMoveEvenMore
 	dec [hl]
 	jr .preferMove
@@ -676,9 +678,6 @@ TrainerAI:
 	ld a, [wIsInBattle]
 	dec a
 	ret z ; if not a trainer, we're done here
-	ld a, [wCurMap]
-	cp BATTLE_TENT
-	ret z ; if we are in battle tent, we are done
 	ld a, [wLinkState]
 	cp LINK_STATE_BATTLING
 	ret z ; if in a link battle, we're done as well
@@ -732,12 +731,9 @@ BlackbeltAI:
 	jp AIUseXAttack
 
 GiovanniAI:
-	cp 20 percent + 1
+	cp 25 percent + 1
 	ret nc
-	ld a, [wEnemyBattleStatus2]
+	jp AIUseXAttack ; Used to use a Guard Spec. This will make the item use have a proper impact - healing doesn't feel right for a trainer fixated on strength.
-	bit GETTING_PUMPED, a
-	ret nz
-	jp AIUseDireHit
 
 CooltrainerMAI:
 	cp 20 percent + 1
@@ -765,41 +761,46 @@ BrockAI:
 	jp AIUseFullHeal
 
 MistyAI:
-	cp 20 percent + 1
+	cp 25 percent + 1
 	ret nc
-	jp AIUseXDefend
+	ld a, 10
+	call AICheckIfHPBelowFraction
+	ret nc
+	jp AIUseSuperPotion ; Replicates Starmie using Recover. Unlike other trainers that heal, Misty will do this 26% of the time instead of 51%.
 
 LtSurgeAI:
-	cp 10 percent + 1
+	cp 20 percent + 1
 	ret nc
-	jp AIUseXSpeed
+	jp AIUseXSpecial
 
 ErikaAI:
 	cp 50 percent + 1
 	ret nc
-	ld a, 5
+	ld a, 10
 	call AICheckIfHPBelowFraction
 	ret nc
 	jp AIUseSuperPotion
 
 KogaAI:
-	cp 10 percent + 1
+	cp 50 percent + 1
 	ret nc
-	jp AIUseXAttack
+	ld a, 10
-
-BlaineAI:	;blaine needs to check HP. this was an oversight
-	cp 40 percent + 1
-	jr nc, .blainereturn
-	ld a, 2
 	call AICheckIfHPBelowFraction
-	jp c, AIUseSuperPotion
+	ret nc
-.blainereturn
+	jp AIUseSuperPotion ; Koga is weird - I don't think anything fits. X Attack is certainly not the move though...
-	ret
+
+BlaineAI:
+	cp 25 percent + 1
+	ret nc
+	ld a, 10
+	call AICheckIfHPBelowFraction
+	ret nc ; this fixes the super potion thing - PvK
+	jp AIUseHyperPotion ; Instead of a Super Potion though, let's give him this. More impactful for the sixth gym while staying true to the meme that everyone knows Gen 1 Blaine for.
 
 SabrinaAI:
 	cp 25 percent + 1
 	ret nc
-	ld a, 5
+	ld a, 10
 	call AICheckIfHPBelowFraction
 	ret nc
 	jp AIUseHyperPotion
@@ -810,7 +811,7 @@ Rival2AI:
 	ld a, 5
 	call AICheckIfHPBelowFraction
 	ret nc
-	jp AIUseHyperPotion
+	jp AIUseSuperPotion
 
 Rival3AI:
 	cp 40 percent - 1
@@ -821,43 +822,51 @@ Rival3AI:
 	jp AIUseFullRestore
 
 LoreleiAI:
-	cp 50 percent + 1
+	cp 15 percent + 1
+	ret nc
+	jp AIUseXSpecial
+	cp 40 percent + 1
 	ret nc
 	ld a, 5
 	call AICheckIfHPBelowFraction
 	ret nc
-	jp AIUseHyperPotion
+	jp AIUseFullRestore
 
 BrunoAI:
-	;cp 10 percent + 1
+	cp 15 percent + 1
-	;ret nc
+	ret nc
-	;jp AIUseXDefend
+	jp AIUseXAttack
-	cp 30 percent + 1
+	cp 40 percent + 1
-	jr nc, .brunoreturn
+	ret nc
 	ld a, 5
 	call AICheckIfHPBelowFraction
-	jp c, AIUseHyperPotion
+	ret nc
-.brunoreturn
+	jp AIUseFullRestore
-	ret
 
 AgathaAI:
 	cp 8 percent
 	jp c, AISwitchIfEnoughMons
-	cp 50 percent + 1
+	cp 15 percent + 1
 	ret nc
-	ld a, 4
+	jp AIUseXAccuracy ; hahahahahahahaha
-	call AICheckIfHPBelowFraction
+	cp 40 percent + 1
-	ret nc
-	jp AIUseHyperPotion
-
-LanceAI:
-	cp 50 percent + 1
 	ret nc
 	ld a, 5
 	call AICheckIfHPBelowFraction
 	ret nc
 	jp AIUseFullRestore
 
+LanceAI:
+	cp 15 percent + 1
+	ret nc
+	jp AIUseXSpecial
+	cp 50 percent + 1
+	ret nc
+	ld a, 10
+	call AICheckIfHPBelowFraction
+	ret nc
+	jp AIUseFullRestore
+
 GenericAI:
 	and a ; clear carry
 	ret
@@ -1087,12 +1096,12 @@ AICureStatus:	;shinpokerednote: CHANGED: modified to be more robust and also und
 	res BADLY_POISONED, [hl]	;clear toxic bit
 	ret
 
-;AIUseXAccuracy: ; unused
+AIUseXAccuracy:
-;	call AIPlayRestoringSFX
+	call AIPlayRestoringSFX
-;	ld hl, wEnemyBattleStatus2
+	ld hl, wEnemyBattleStatus2
-;	set 0, [hl]
+	set 0, [hl]
-;	ld a, X_ACCURACY
+	ld a, X_ACCURACY
-;	jp AIPrintItemUse
+	jp AIPrintItemUse
 
 ;AIUseGuardSpec: ; PureRGBnote: CHANGED: now unused
 ;	call AIPlayRestoringSFX

engine/battle/unused_stats_functions.asm

@@ -1,4 +1,54 @@
-; Used by the pureRGB AI
+;shinpokerednote: ADDED: doubles the given stat
+DoubleSelectedStats:
+	ldh a, [hWhoseTurn]
+	and a
+	ld a, [wPlayerStatsToDouble]
+	ld hl, wBattleMonAttack
+	jr z, .notEnemyTurn
+	ld a, [wEnemyStatsToDouble]
+	ld hl, wEnemyMonAttack
+.notEnemyTurn
+	ld c, 4
+	ld b, a
+.loop
+	srl b
+	call c, .doubleStat
+	inc hl
+	inc hl
+	dec c
+	ret z
+	jr .loop
+.doubleStat
+	push bc
+	ld a, [hli]
+	ld b, a
+	ld c, [hl] ; bc holds value of stat to double
+;double the stat
+	sla c
+	rl b
+;cap stat at 999
+	;b register contains high byte & c register contains low byte
+	ld a, c ;let's work on low byte first. Note that decimal 999 is $03E7 in hex.
+	sub 999 % $100 ;a = a - ($03E7 % $100). Gives a = a - $E7. A byte % $100 always gives the lesser nibble.
+	;Note that if a < $E7 then the carry bit 'c' in the flag register gets set due to overflowing with a negative result.
+	ld a, b ;now let's work on the high byte
+	sbc 999 / $100 ;a = a - ($03E7 / $100 + c_flag). Gives a = a - ($03 + c_flag). A byte / $100 always gives the greater nibble.
+	;Note again that if a < $03 then the carry bit remains set. 
+	;If the bit is already set from the lesser nibble, then its addition here can still make it remain set if a is low enough.
+	jr c, .donecapping ;jump to next marker if the c_flag is set. This only remains set if BC <  the cap of $03E7.
+	;else let's continue and set the 999 cap
+	ld a, 999 / $100 ; else load $03 into a
+	ld b, a ;and store it as the high byte
+	ld a, 999 % $100 ; else load $E7 into a
+	ld c, a ;and store it as the low byte
+	;now registers b & c together contain $03E7 for a capped stat value of 999
+.donecapping
+	ld a, c
+	ld [hld], a
+	ld [hl], b
+	pop bc
+	ret
+	
 ;shinpokerednote: ADDED: doubles attack if burned or quadruples speed if paralyzed.
 ;It's meant to be run right before healing paralysis or burn so as to 
 ;undo the stat changes.
@@ -31,35 +81,6 @@ UndoBurnParStats:
 	ld [de], a	;reset the stat change bits
 	ret
 
-; Reused for pureRGB AI
-DoubleSelectedStats:
-	ldh a, [hWhoseTurn]
-	and a
-	ld a, [wPlayerStatsToDouble]
-	ld hl, wBattleMonAttack + 1
-	jr z, .notEnemyTurn
-	ld a, [wEnemyStatsToDouble]
-	ld hl, wEnemyMonAttack + 1
-.notEnemyTurn
-	ld c, 4
-	ld b, a
-.loop
-	srl b
-	call c, .doubleStat
-	inc hl
-	inc hl
-	dec c
-	ret z
-	jr .loop
-.doubleStat
-	ld a, [hl]
-	add a
-	ld [hld], a
-	ld a, [hl]
-	rl a
-	ld [hli], a
-	ret
-
 ; does nothing since no stats are ever selected (barring glitches)
 ;HalveSelectedStats:
 ;	ldh a, [hWhoseTurn]

main.asm

@@ -186,6 +186,8 @@ SECTION "Battle Engine 7", ROMX
 
 INCLUDE "data/moves/moves.asm"
 INCLUDE "data/pokemon/cries.asm"
+INCLUDE "engine/battle/scroll_draw_trainer_pic.asm"
+INCLUDE "engine/battle/trainer_ai.asm"
 INCLUDE "engine/battle/unused_stats_functions.asm"
 INCLUDE "engine/battle/move_effects/heal.asm"
 INCLUDE "engine/battle/move_effects/transform.asm"
@@ -249,8 +251,6 @@ INCLUDE "engine/events/hidden_objects/indigo_plateau_hq.asm"
 
 SECTION "Battle Engine 9", ROMX
 
-INCLUDE "engine/battle/scroll_draw_trainer_pic.asm"
-INCLUDE "engine/battle/trainer_ai.asm"
 INCLUDE "engine/battle/draw_hud_pokeball_gfx.asm"