pokecrystal-board/engine/overworld/wildmons.asm

LoadWildMonData: ; 29ff8
	call _GrassWildmonLookup
	jr c, .copy
	ld hl, wMornEncounterRate
	xor a
	ld [hli], a
	ld [hli], a
	ld [hl], a
	jr .done_copy

.copy
	inc hl
	inc hl
	ld de, wMornEncounterRate
	ld bc, 3
	call CopyBytes
.done_copy
	call _WaterWildmonLookup
	ld a, 0
	jr nc, .no_copy
	inc hl
	inc hl
	ld a, [hl]
.no_copy
	ld [wWaterEncounterRate], a
	ret

FindNest: ; 2a01f
; Parameters:
; e: 0 = Johto, 1 = Kanto
; wNamedObjectIndexBuffer: species
	hlcoord 0, 0
	ld bc, SCREEN_WIDTH * SCREEN_HEIGHT
	xor a
	call ByteFill
	ld a, e
	and a
	jr nz, .kanto
	decoord 0, 0
	ld hl, JohtoGrassWildMons
	call .FindGrass
	ld hl, JohtoWaterWildMons
	call .FindWater
	call .RoamMon1
	call .RoamMon2
	ret

.kanto
	decoord 0, 0
	ld hl, KantoGrassWildMons
	call .FindGrass
	ld hl, KantoWaterWildMons
	jp .FindWater
; 2a052

.FindGrass: ; 2a052
	ld a, [hl]
	cp -1
	ret z
	push hl
	ld a, [hli]
	ld b, a
	ld a, [hli]
	ld c, a
	inc hl
	inc hl
	inc hl
	ld a, NUM_GRASSMON * 3
	call .SearchMapForMon
	jr nc, .next_grass
	ld [de], a
	inc de

.next_grass
	pop hl
	ld bc, GRASS_WILDDATA_LENGTH
	add hl, bc
	jr .FindGrass
; 2a06e

.FindWater: ; 2a06e
	ld a, [hl]
	cp -1
	ret z
	push hl
	ld a, [hli]
	ld b, a
	ld a, [hli]
	ld c, a
	inc hl
	ld a, 3
	call .SearchMapForMon
	jr nc, .next_water
	ld [de], a
	inc de

.next_water
	pop hl
	ld bc, 3 * 3
	add hl, bc
	jr .FindWater
; 2a088

.SearchMapForMon: ; 2a088
	inc hl
.ScanMapLoop:
	push af
	ld a, [wNamedObjectIndexBuffer]
	cp [hl]
	jr z, .found
	inc hl
	inc hl
	pop af
	dec a
	jr nz, .ScanMapLoop
	and a
	ret

.found
	pop af
	jp .AppendNest
; 2a09c

.AppendNest: ; 2a09c
	push de
	call GetWorldMapLocation
	ld c, a
	hlcoord 0, 0
	ld de, SCREEN_WIDTH * SCREEN_HEIGHT
.AppendNestLoop:
	ld a, [hli]
	cp c
	jr z, .found_nest
	dec de
	ld a, e
	or d
	jr nz, .AppendNestLoop
	ld a, c
	pop de
	scf
	ret

.found_nest
	pop de
	and a
	ret
; 2a0b7

.RoamMon1: ; 2a0b7
	ld a, [wRoamMon1Species]
	ld b, a
	ld a, [wNamedObjectIndexBuffer]
	cp b
	ret nz
	ld a, [wRoamMon1MapGroup]
	ld b, a
	ld a, [wRoamMon1MapNumber]
	ld c, a
	call .AppendNest
	ret nc
	ld [de], a
	inc de
	ret
; 2a0cf

.RoamMon2: ; 2a0cf
	ld a, [wRoamMon2Species]
	ld b, a
	ld a, [wNamedObjectIndexBuffer]
	cp b
	ret nz
	ld a, [wRoamMon2MapGroup]
	ld b, a
	ld a, [wRoamMon2MapNumber]
	ld c, a
	call .AppendNest
	ret nc
	ld [de], a
	inc de
	ret
; 2a0e7

TryWildEncounter:: ; 2a0e7
; Try to trigger a wild encounter.
	call .EncounterRate
	jr nc, .no_battle
	call ChooseWildEncounter
	jr nz, .no_battle
	call CheckRepelEffect
	jr nc, .no_battle
	xor a
	ret

.no_battle
	xor a ; BATTLETYPE_NORMAL
	ld [wTempWildMonSpecies], a
	ld [wBattleType], a
	ld a, 1
	and a
	ret
; 2a103

.EncounterRate: ; 2a103
	call GetMapEncounterRate
	call ApplyMusicEffectOnEncounterRate
	call ApplyCleanseTagEffectOnEncounterRate
	call Random
	cp b
	ret
; 2a111

GetMapEncounterRate: ; 2a111
	ld hl, wMornEncounterRate
	call CheckOnWater
	ld a, wWaterEncounterRate - wMornEncounterRate
	jr z, .ok
	ld a, [wTimeOfDay]
.ok
	ld c, a
	ld b, 0
	add hl, bc
	ld b, [hl]
	ret
; 2a124

ApplyMusicEffectOnEncounterRate:: ; 2a124
; Pokemon March and Ruins of Alph signal double encounter rate.
; Pokemon Lullaby halves encounter rate.
	ld a, [wMapMusic]
	cp MUSIC_POKEMON_MARCH
	jr z, .double
	cp MUSIC_RUINS_OF_ALPH_RADIO
	jr z, .double
	cp MUSIC_POKEMON_LULLABY
	ret nz
	srl b
	ret

.double
	sla b
	ret
; 2a138

ApplyCleanseTagEffectOnEncounterRate:: ; 2a138
; Cleanse Tag halves encounter rate.
	ld hl, wPartyMon1Item
	ld de, PARTYMON_STRUCT_LENGTH
	ld a, [wPartyCount]
	ld c, a
.loop
	ld a, [hl]
	cp CLEANSE_TAG
	jr z, .cleansetag
	add hl, de
	dec c
	jr nz, .loop
	ret

.cleansetag
	srl b
	ret
; 2a14f

ChooseWildEncounter: ; 2a14f
	call LoadWildMonDataPointer
	jp nc, .nowildbattle
	call CheckEncounterRoamMon
	jp c, .startwildbattle

	inc hl
	inc hl
	inc hl
	call CheckOnWater
	ld de, WaterMonProbTable
	jr z, .watermon
	inc hl
	inc hl
	ld a, [wTimeOfDay]
	ld bc, $e
	call AddNTimes
	ld de, GrassMonProbTable

.watermon
; hl contains the pointer to the wild mon data, let's save that to the stack
	push hl
.randomloop
	call Random
	cp 100
	jr nc, .randomloop
	inc a ; 1 <= a <= 100
	ld b, a
	ld h, d
	ld l, e
; This next loop chooses which mon to load up.
.prob_bracket_loop
	ld a, [hli]
	cp b
	jr nc, .got_it
	inc hl
	jr .prob_bracket_loop

.got_it
	ld c, [hl]
	ld b, 0
	pop hl
	add hl, bc ; this selects our mon
	ld a, [hli]
	ld b, a
; If the Pokemon is encountered by surfing, we need to give the levels some variety.
	call CheckOnWater
	jr nz, .ok
; Check if we buff the wild mon, and by how much.
	call Random
	cp 35 percent
	jr c, .ok
	inc b
	cp 65 percent
	jr c, .ok
	inc b
	cp 85 percent
	jr c, .ok
	inc b
	cp 95 percent
	jr c, .ok
	inc b
; Store the level
.ok
	ld a, b
	ld [wCurPartyLevel], a
	ld b, [hl]
	; ld a, b
	call ValidateTempWildMonSpecies
	jr c, .nowildbattle

	ld a, b ; This is in the wrong place.
	cp UNOWN
	jr nz, .done

	ld a, [wUnlockedUnowns]
	and a
	jr z, .nowildbattle

.done
	jr .loadwildmon

.nowildbattle
	ld a, 1
	and a
	ret

.loadwildmon
	ld a, b
	ld [wTempWildMonSpecies], a

.startwildbattle
	xor a
	ret
; 2a1cb

INCLUDE "data/wild/probabilities.asm"

CheckRepelEffect:: ; 2a1df
; If there is no active Repel, there's no need to be here.
	ld a, [wRepelEffect]
	and a
	jr z, .encounter
; Get the first Pokemon in your party that isn't fainted.
	ld hl, wPartyMon1HP
	ld bc, PARTYMON_STRUCT_LENGTH - 1
.loop
	ld a, [hli]
	or [hl]
	jr nz, .ok
	add hl, bc
	jr .loop

.ok
; to PartyMonLevel
rept 4
	dec hl
endr

	ld a, [wCurPartyLevel]
	cp [hl]
	jr nc, .encounter
	and a
	ret

.encounter
	scf
	ret
; 2a200

LoadWildMonDataPointer: ; 2a200
	call CheckOnWater
	jr z, _WaterWildmonLookup

_GrassWildmonLookup: ; 2a205
	ld hl, SwarmGrassWildMons
	ld bc, GRASS_WILDDATA_LENGTH
	call _SwarmWildmonCheck
	ret c
	ld hl, JohtoGrassWildMons
	ld de, KantoGrassWildMons
	call _JohtoWildmonCheck
	ld bc, GRASS_WILDDATA_LENGTH
	jr _NormalWildmonOK

_WaterWildmonLookup: ; 2a21d
	ld hl, SwarmWaterWildMons
	ld bc, WATER_WILDDATA_LENGTH
	call _SwarmWildmonCheck
	ret c
	ld hl, JohtoWaterWildMons
	ld de, KantoWaterWildMons
	call _JohtoWildmonCheck
	ld bc, WATER_WILDDATA_LENGTH
	jr _NormalWildmonOK

_JohtoWildmonCheck:
	call IsInJohto
	and a
	ret z
	ld h, d
	ld l, e
	ret

_SwarmWildmonCheck:
	call CopyCurrMapDE
	push hl
	ld hl, wSwarmFlags
	bit SWARMFLAGS_DUNSPARCE_SWARM_F, [hl]
	pop hl
	jr z, .CheckYanma
	ld a, [wDunsparceMapGroup]
	cp d
	jr nz, .CheckYanma
	ld a, [wDunsparceMapNumber]
	cp e
	jr nz, .CheckYanma
	call LookUpWildmonsForMapDE
	jr nc, _NoSwarmWildmon
	scf
	ret

.CheckYanma:
	push hl
	ld hl, wSwarmFlags
	bit SWARMFLAGS_YANMA_SWARM_F, [hl]
	pop hl
	jr z, _NoSwarmWildmon
	ld a, [wYanmaMapGroup]
	cp d
	jr nz, _NoSwarmWildmon
	ld a, [wYanmaMapNumber]
	cp e
	jr nz, _NoSwarmWildmon
	call LookUpWildmonsForMapDE
	jr nc, _NoSwarmWildmon
	scf
	ret

_NoSwarmWildmon:
	and a
	ret

_NormalWildmonOK:
	call CopyCurrMapDE
	jr LookUpWildmonsForMapDE
; 2a27f

CopyCurrMapDE: ; 2a27f
	ld a, [wMapGroup]
	ld d, a
	ld a, [wMapNumber]
	ld e, a
	ret
; 2a288

LookUpWildmonsForMapDE: ; 2a288
.loop
	push hl
	ld a, [hl]
	inc a
	jr z, .nope
	ld a, d
	cp [hl]
	jr nz, .next
	inc hl
	ld a, e
	cp [hl]
	jr z, .yup

.next
	pop hl
	add hl, bc
	jr .loop

.nope
	pop hl
	and a
	ret

.yup
	pop hl
	scf
	ret
; 2a2a0


InitRoamMons: ; 2a2a0
; initialize wRoamMon structs

; species
	ld a, RAIKOU
	ld [wRoamMon1Species], a
	ld a, ENTEI
	ld [wRoamMon2Species], a

; level
	ld a, 40
	ld [wRoamMon1Level], a
	ld [wRoamMon2Level], a

; raikou starting map
	ld a, GROUP_ROUTE_42
	ld [wRoamMon1MapGroup], a
	ld a, MAP_ROUTE_42
	ld [wRoamMon1MapNumber], a

; entei starting map
	ld a, GROUP_ROUTE_37
	ld [wRoamMon2MapGroup], a
	ld a, MAP_ROUTE_37
	ld [wRoamMon2MapNumber], a

; hp
	xor a ; generate new stats
	ld [wRoamMon1HP], a
	ld [wRoamMon2HP], a

	ret
; 2a2ce


CheckEncounterRoamMon: ; 2a2ce
	push hl
; Don't trigger an encounter if we're on water.
	call CheckOnWater
	jr z, .DontEncounterRoamMon
; Load the current map group and number to de
	call CopyCurrMapDE
; Randomly select a beast.
	call Random
	cp 100 ; 25/64 chance
	jr nc, .DontEncounterRoamMon
	and %00000011 ; Of that, a 3/4 chance.  Running total: 75/256, or around 29.3%.
	jr z, .DontEncounterRoamMon
	dec a ; 1/3 chance that it's Entei, 1/3 chance that it's Raikou
; Compare its current location with yours
	ld hl, wRoamMon1MapGroup
	ld c, a
	ld b, 0
	ld a, 7 ; length of the roam_struct
	call AddNTimes
	ld a, d
	cp [hl]
	jr nz, .DontEncounterRoamMon
	inc hl
	ld a, e
	cp [hl]
	jr nz, .DontEncounterRoamMon
; We've decided to take on a beast, so stage its information for battle.
	dec hl
	dec hl
	dec hl
	ld a, [hli]
	ld [wTempWildMonSpecies], a
	ld a, [hl]
	ld [wCurPartyLevel], a
	ld a, BATTLETYPE_ROAMING
	ld [wBattleType], a

	pop hl
	scf
	ret

.DontEncounterRoamMon:
	pop hl
	and a
	ret
; 2a30d


UpdateRoamMons: ; 2a30d
	ld a, [wRoamMon1MapGroup]
	cp GROUP_N_A
	jr z, .SkipRaikou
	ld b, a
	ld a, [wRoamMon1MapNumber]
	ld c, a
	call .Update
	ld a, b
	ld [wRoamMon1MapGroup], a
	ld a, c
	ld [wRoamMon1MapNumber], a

.SkipRaikou:
	ld a, [wRoamMon2MapGroup]
	cp GROUP_N_A
	jr z, .SkipEntei
	ld b, a
	ld a, [wRoamMon2MapNumber]
	ld c, a
	call .Update
	ld a, b
	ld [wRoamMon2MapGroup], a
	ld a, c
	ld [wRoamMon2MapNumber], a

.SkipEntei:
	ld a, [wRoamMon3MapGroup]
	cp GROUP_N_A
	jr z, .Finished
	ld b, a
	ld a, [wRoamMon3MapNumber]
	ld c, a
	call .Update
	ld a, b
	ld [wRoamMon3MapGroup], a
	ld a, c
	ld [wRoamMon3MapNumber], a

.Finished:
	jp _BackUpMapIndices
; 2a355


.Update: ; 2a355
	ld hl, RoamMaps
.loop
; Are we at the end of the table?
	ld a, [hl]
	cp -1
	ret z
; Is this the correct entry?
	ld a, b
	cp [hl]
	jr nz, .next
	inc hl
	ld a, c
	cp [hl]
	jr z, .yes
; We don't have the correct entry yet, so let's continue.  A 0 terminates each entry.
.next
	ld a, [hli]
	and a
	jr nz, .next
	jr .loop

; We have the correct entry now, so let's choose a random map from it.
.yes
	inc hl
	ld d, h
	ld e, l
.update_loop
	ld h, d
	ld l, e
; Choose which map to warp to.
	call Random
	and %00011111 ; 1/8n chance it moves to a completely random map, where n is the number of roaming connections from the current map.
	jr z, JumpRoamMon
	and %11
	cp [hl]
	jr nc, .update_loop ; invalid index, try again
	inc hl
	ld c, a
	ld b, $0
	add hl, bc
	add hl, bc
	ld a, [wRoamMons_LastMapGroup]
	cp [hl]
	jr nz, .done
	inc hl
	ld a, [wRoamMons_LastMapNumber]
	cp [hl]
	jr z, .update_loop
	dec hl

.done
	ld a, [hli]
	ld b, a
	ld c, [hl]
	ret

JumpRoamMons: ; 2a394
	ld a, [wRoamMon1MapGroup]
	cp GROUP_N_A
	jr z, .SkipRaikou
	call JumpRoamMon
	ld a, b
	ld [wRoamMon1MapGroup], a
	ld a, c
	ld [wRoamMon1MapNumber], a

.SkipRaikou:
	ld a, [wRoamMon2MapGroup]
	cp GROUP_N_A
	jr z, .SkipEntei
	call JumpRoamMon
	ld a, b
	ld [wRoamMon2MapGroup], a
	ld a, c
	ld [wRoamMon2MapNumber], a

.SkipEntei:
	ld a, [wRoamMon3MapGroup]
	cp GROUP_N_A
	jr z, .Finished
	call JumpRoamMon
	ld a, b
	ld [wRoamMon3MapGroup], a
	ld a, c
	ld [wRoamMon3MapNumber], a

.Finished:
	jp _BackUpMapIndices

JumpRoamMon: ; 2a3cd
.loop
	ld hl, RoamMaps
.innerloop1                   ; This loop happens to be unnecessary.
	call Random               ; Choose a random number.
	maskbits NUM_ROAMMON_MAPS ; Mask the number to limit it between 0 and 15.
	cp NUM_ROAMMON_MAPS       ; If the number is not less than 16, try again.
	jr nc, .innerloop1        ; I'm sure you can guess why this check is bogus.
	inc a
	ld b, a
.innerloop2 ; Loop to get hl to the address of the chosen roam map.
	dec b
	jr z, .ok
.innerloop3 ; Loop to skip the current roam map, which is terminated by a 0.
	ld a, [hli]
	and a
	jr nz, .innerloop3
	jr .innerloop2
; Check to see if the selected map is the one the player is currently in.  If so, try again.
.ok
	ld a, [wMapGroup]
	cp [hl]
	jr nz, .done
	inc hl
	ld a, [wMapNumber]
	cp [hl]
	jr z, .loop
	dec hl
; Return the map group and number in bc.
.done
	ld a, [hli]
	ld b, a
	ld c, [hl]
	ret
; 2a3f6

_BackUpMapIndices: ; 2a3f6
	ld a, [wRoamMons_CurrentMapNumber]
	ld [wRoamMons_LastMapNumber], a
	ld a, [wRoamMons_CurrentMapGroup]
	ld [wRoamMons_LastMapGroup], a
	ld a, [wMapNumber]
	ld [wRoamMons_CurrentMapNumber], a
	ld a, [wMapGroup]
	ld [wRoamMons_CurrentMapGroup], a
	ret
; 2a40f


INCLUDE "data/wild/roammon_maps.asm"


ValidateTempWildMonSpecies: ; 2a4a0
; Due to a development oversight, this function is called with the wild Pokemon's level, not its species, in a.
	and a
	jr z, .nowildmon ; = 0
	cp NUM_POKEMON + 1 ; 252
	jr nc, .nowildmon ; >= 252
	and a ; 1 <= Species <= 251
	ret

.nowildmon
	scf
	ret
; 2a4ab

; Finds a rare wild Pokemon in the route of the trainer calling, then checks if it's been Seen already.
; The trainer will then tell you about the Pokemon if you haven't seen it.
RandomUnseenWildMon: ; 2a4ab
	farcall GetCallerLocation
	ld d, b
	ld e, c
	ld hl, JohtoGrassWildMons
	ld bc, GRASS_WILDDATA_LENGTH
	call LookUpWildmonsForMapDE
	jr c, .GetGrassmon
	ld hl, KantoGrassWildMons
	call LookUpWildmonsForMapDE
	jr nc, .done

.GetGrassmon:
	push hl
	ld bc, 5 + 4 * 2 ; Location of the level of the 5th wild Pokemon in that map
	add hl, bc
	ld a, [wTimeOfDay]
	ld bc, NUM_GRASSMON * 2
	call AddNTimes
.randloop1
	call Random
	and %11
	jr z, .randloop1
	dec a
	ld c, a
	ld b, $0
	add hl, bc
	add hl, bc
; We now have the pointer to one of the last (rarest) three wild Pokemon found in that area.
	inc hl
	ld c, [hl] ; Contains the species index of this rare Pokemon
	pop hl
	ld de, 5 + 0 * 2
	add hl, de
	inc hl ; Species index of the most common Pokemon on that route
	ld b, 4
.loop2
	ld a, [hli]
	cp c ; Compare this most common Pokemon with the rare one stored in c.
	jr z, .done
	inc hl
	dec b
	jr nz, .loop2
; This Pokemon truly is rare.
	push bc
	dec c
	ld a, c
	call CheckSeenMon
	pop bc
	jr nz, .done
; Since we haven't seen it, have the caller tell us about it.
	ld de, wStringBuffer1
	call CopyName1
	ld a, c
	ld [wNamedObjectIndexBuffer], a
	call GetPokemonName
	ld hl, .SawRareMonText
	call PrintText
	xor a
	ld [wScriptVar], a
	ret

.done
	ld a, $1
	ld [wScriptVar], a
	ret

.SawRareMonText:
	; I just saw some rare @  in @ . I'll call you if I see another rare #MON, OK?
	text_jump UnknownText_0x1bd34b
	db "@"
; 0x2a51f

RandomPhoneWildMon: ; 2a51f
	farcall GetCallerLocation
	ld d, b
	ld e, c
	ld hl, JohtoGrassWildMons
	ld bc, GRASS_WILDDATA_LENGTH
	call LookUpWildmonsForMapDE
	jr c, .ok
	ld hl, KantoGrassWildMons
	call LookUpWildmonsForMapDE

.ok
	ld bc, 5 + 0 * 2
	add hl, bc
	ld a, [wTimeOfDay]
	inc a
	ld bc, NUM_GRASSMON * 2
.loop
	dec a
	jr z, .done
	add hl, bc
	jr .loop

.done
	call Random
	and %11
	ld c, a
	ld b, $0
	add hl, bc
	add hl, bc
	inc hl
	ld a, [hl]
	ld [wNamedObjectIndexBuffer], a
	call GetPokemonName
	ld hl, wStringBuffer1
	ld de, wStringBuffer4
	ld bc, MON_NAME_LENGTH
	jp CopyBytes
; 2a567

RandomPhoneMon: ; 2a567
; Get a random monster owned by the trainer who's calling.
	farcall GetCallerLocation
	ld hl, TrainerGroups
	ld a, d
	dec a
	ld c, a
	ld b, 0
	add hl, bc
	add hl, bc
	ld a, BANK(TrainerGroups)
	call GetFarHalfword

.skip_trainer
	dec e
	jr z, .skipped
.skip
	ld a, BANK(Trainers)
	call GetFarByte
	inc hl
	cp -1
	jr nz, .skip
	jr .skip_trainer
.skipped

.skip_name
	ld a, BANK(Trainers)
	call GetFarByte
	inc hl
	cp "@"
	jr nz, .skip_name

	ld a, BANK(Trainers)
	call GetFarByte
	inc hl
	ld bc, 2 ; level, species
	cp TRAINERTYPE_NORMAL
	jr z, .got_mon_length
	ld bc, 2 + NUM_MOVES ; level, species, moves
	cp TRAINERTYPE_MOVES
	jr z, .got_mon_length
	ld bc, 2 + 1 ; level, species, item
	cp TRAINERTYPE_ITEM
	jr z, .got_mon_length
	; TRAINERTYPE_ITEM_MOVES
	ld bc, 2 + 1 + NUM_MOVES ; level, species, item, moves
.got_mon_length

	ld e, 0
	push hl
.count_mon
	inc e
	add hl, bc
	ld a, BANK(Trainers)
	call GetFarByte
	cp -1
	jr nz, .count_mon
	pop hl

.rand
	call Random
	maskbits PARTY_LENGTH
	cp e
	jr nc, .rand

	inc a
.get_mon
	dec a
	jr z, .got_mon
	add hl, bc
	jr .get_mon
.got_mon

	inc hl ; species
	ld a, BANK(Trainers)
	call GetFarByte
	ld [wNamedObjectIndexBuffer], a
	call GetPokemonName
	ld hl, wStringBuffer1
	ld de, wStringBuffer4
	ld bc, MON_NAME_LENGTH
	jp CopyBytes
; 2a5e9


INCLUDE "data/wild/johto_grass.asm"
INCLUDE "data/wild/johto_water.asm"
INCLUDE "data/wild/kanto_grass.asm"
INCLUDE "data/wild/kanto_water.asm"
INCLUDE "data/wild/swarm_grass.asm"
INCLUDE "data/wild/swarm_water.asm"