ref: 013c2c7d6637b14e4779fd769e3af311553404be
dir: /engine/battle/wild_encounters.asm/
; try to initiate a wild pokemon encounter ; returns success in Z TryDoWildEncounter: ; 13870 (4:7870) ld a, [wNPCMovementScriptPointerTableNum] and a ret nz ld a, [wd736] and a ret nz callab IsPlayerStandingOnDoorTileOrWarpTile jr nc, .notStandingOnDoorOrWarpTile .CantEncounter ld a, $1 and a ret .notStandingOnDoorOrWarpTile callab IsPlayerJustOutsideMap jr z, .CantEncounter ld a, [wRepelRemainingSteps] and a jr z, .asm_1389e dec a jr z, .lastRepelStep ld [wRepelRemainingSteps], a .asm_1389e ; determine if wild pokemon can appear in the half-block we're standing in ; is the bottom right tile (9,9) of the half-block we're standing in a grass/water tile? hlCoord 9, 9 ld c, [hl] ld a, [W_GRASSTILE] cp c ld a, [W_GRASSRATE] jr z, .CanEncounter ld a, $14 ; in all tilesets with a water tile, this is its id cp c ld a, [W_WATERRATE] jr z, .CanEncounter ; even if not in grass/water, standing anywhere we can encounter pokemon ; so long as the map is "indoor" and has wild pokemon defined. ; ...as long as it's not Viridian Forest or Safari Zone. ld a, [W_CURMAP] cp REDS_HOUSE_1F ; is this an indoor map? jr c, .CantEncounter2 ld a, [W_CURMAPTILESET] cp FOREST ; Viridian Forest/Safari Zone jr z, .CantEncounter2 ld a, [W_GRASSRATE] .CanEncounter ; compare encounter chance with a random number to determine if there will be an encounter ld b, a ld a, [hRandomAdd] cp b jr nc, .CantEncounter2 ld a, [hRandomSub] ld b, a ld hl, WildMonEncounterSlotChances .determineEncounterSlot ld a, [hli] cp b jr nc, .gotEncounterSlot inc hl jr .determineEncounterSlot .gotEncounterSlot ; determine which wild pokemon (grass or water) can appear in the half-block we're standing in ld c, [hl] ld hl, W_GRASSMONS aCoord 8, 9 cp $14 ; is the bottom left tile (8,9) of the half-block we're standing in a water tile? jr nz, .gotWildEncounterType ; else, it's treated as a grass tile by default ld hl, W_WATERMONS ; since the bottom right tile of a "left shore" half-block is $14 but the bottom left tile is not, ; "left shore" half-blocks (such as the one in the east coast of Cinnabar) load grass encounters. .gotWildEncounterType ld b, $0 add hl, bc ld a, [hli] ld [W_CURENEMYLVL], a ld a, [hl] ld [wcf91], a ld [wEnemyMonSpecies2], a ld a, [wRepelRemainingSteps] and a jr z, .willEncounter ld a, [wPartyMon1Level] ld b, a ld a, [W_CURENEMYLVL] cp b jr c, .CantEncounter2 ; repel prevents encounters if the leading party mon's level is higher than the wild mon jr .willEncounter .lastRepelStep ld [wRepelRemainingSteps], a ld a, $d2 ld [H_DOWNARROWBLINKCNT2], a call EnableAutoTextBoxDrawing call DisplayTextID .CantEncounter2 ld a, $1 and a ret .willEncounter xor a ret WildMonEncounterSlotChances: ; 13918 (4:7918) ; There are 10 slots for wild pokemon, and this is the table that defines how common each of ; those 10 slots is. A random number is generated and then the first byte of each pair in this ; table is compared against that random number. If the random number is less than or equal ; to the first byte, then that slot is chosen. The second byte is double the slot number. db $32, $00 ; 51/256 = 19.9% chance of slot 0 db $65, $02 ; 51/256 = 19.9% chance of slot 1 db $8C, $04 ; 39/256 = 15.2% chance of slot 2 db $A5, $06 ; 25/256 = 9.8% chance of slot 3 db $BE, $08 ; 25/256 = 9.8% chance of slot 4 db $D7, $0A ; 25/256 = 9.8% chance of slot 5 db $E4, $0C ; 13/256 = 5.1% chance of slot 6 db $F1, $0E ; 13/256 = 5.1% chance of slot 7 db $FC, $10 ; 11/256 = 4.3% chance of slot 8 db $FF, $12 ; 3/256 = 1.2% chance of slot 9