pokecrystal/engine/overworld/player_movement.asm

818 lines
12 KiB
NASM

DoPlayerMovement::
call .GetDPad
ld a, movement_step_sleep
ld [wMovementAnimation], a
xor a
ld [wd041], a
call .TranslateIntoMovement
ld c, a
ld a, [wMovementAnimation]
ld [wPlayerNextMovement], a
ret
.GetDPad:
ldh a, [hJoyDown]
ld [wCurInput], a
; Standing downhill instead moves down.
ld hl, wBikeFlags
bit BIKEFLAGS_DOWNHILL_F, [hl]
ret z
ld c, a
and D_PAD
ret nz
ld a, c
or D_DOWN
ld [wCurInput], a
ret
.TranslateIntoMovement:
ld a, [wPlayerState]
cp PLAYER_NORMAL
jr z, .Normal
cp PLAYER_SURF
jr z, .Surf
cp PLAYER_SURF_PIKA
jr z, .Surf
cp PLAYER_BIKE
jr z, .Normal
cp PLAYER_SKATE
jr z, .Ice
.Normal:
call .CheckForced
call .GetAction
call .CheckTile
ret c
call .CheckTurning
ret c
call .TryStep
ret c
call .TryJump
ret c
call .CheckWarp
ret c
jr .NotMoving
.Surf:
call .CheckForced
call .GetAction
call .CheckTile
ret c
call .CheckTurning
ret c
call .TrySurf
ret c
jr .NotMoving
.Ice:
call .CheckForced
call .GetAction
call .CheckTile
ret c
call .CheckTurning
ret c
call .TryStep
ret c
call .TryJump
ret c
call .CheckWarp
ret c
ld a, [wWalkingDirection]
cp STANDING
jr z, .HitWall
call .BumpSound
.HitWall:
call .StandInPlace
xor a
ret
.NotMoving:
ld a, [wWalkingDirection]
cp STANDING
jr z, .Standing
; Walking into an edge warp won't bump.
ld a, [wEngineBuffer4]
and a
jr nz, .CantMove
call .BumpSound
.CantMove:
call ._WalkInPlace
xor a
ret
.Standing:
call .StandInPlace
xor a
ret
.CheckTile:
; Tiles such as waterfalls and warps move the player
; in a given direction, overriding input.
ld a, [wPlayerStandingTile]
ld c, a
call CheckWhirlpoolTile
jr c, .not_whirlpool
ld a, 3
scf
ret
.not_whirlpool
and $f0
cp HI_NYBBLE_CURRENT
jr z, .water
cp HI_NYBBLE_WALK
jr z, .land1
cp HI_NYBBLE_WALK_ALT
jr z, .land2
cp HI_NYBBLE_WARPS
jr z, .warps
jr .no_walk
.water
ld a, c
maskbits NUM_DIRECTIONS
ld c, a
ld b, 0
ld hl, .water_table
add hl, bc
ld a, [hl]
ld [wWalkingDirection], a
jr .continue_walk
.water_table
db RIGHT ; COLL_WATERFALL_RIGHT
db LEFT ; COLL_WATERFALL_LEFT
db UP ; COLL_WATERFALL_UP
db DOWN ; COLL_WATERFALL
.land1
ld a, c
and 7
ld c, a
ld b, 0
ld hl, .land1_table
add hl, bc
ld a, [hl]
cp STANDING
jr z, .no_walk
ld [wWalkingDirection], a
jr .continue_walk
.land1_table
db STANDING ; COLL_BRAKE
db RIGHT ; COLL_WALK_RIGHT
db LEFT ; COLL_WALK_LEFT
db UP ; COLL_WALK_UP
db DOWN ; COLL_WALK_DOWN
db STANDING ; COLL_BRAKE_45
db STANDING ; COLL_BRAKE_46
db STANDING ; COLL_BRAKE_47
.land2
ld a, c
and 7
ld c, a
ld b, 0
ld hl, .land2_table
add hl, bc
ld a, [hl]
cp STANDING
jr z, .no_walk
ld [wWalkingDirection], a
jr .continue_walk
.land2_table
db RIGHT ; COLL_WALK_RIGHT_ALT
db LEFT ; COLL_WALK_LEFT_ALT
db UP ; COLL_WALK_UP_ALT
db DOWN ; COLL_WALK_DOWN_ALT
db STANDING ; COLL_BRAKE_ALT
db STANDING ; COLL_BRAKE_55
db STANDING ; COLL_BRAKE_56
db STANDING ; COLL_BRAKE_57
.warps
ld a, c
cp COLL_DOOR
jr z, .down
cp COLL_DOOR_79
jr z, .down
cp COLL_STAIRCASE
jr z, .down
cp COLL_CAVE
jr nz, .no_walk
.down
ld a, DOWN
ld [wWalkingDirection], a
jr .continue_walk
.no_walk
xor a
ret
.continue_walk
ld a, STEP_WALK
call .DoStep
ld a, 5
scf
ret
.CheckTurning:
; If the player is turning, change direction first. This also lets
; the player change facing without moving by tapping a direction.
ld a, [wPlayerTurningDirection]
cp 0
jr nz, .not_turning
ld a, [wWalkingDirection]
cp STANDING
jr z, .not_turning
ld e, a
ld a, [wPlayerDirection]
rrca
rrca
maskbits NUM_DIRECTIONS
cp e
jr z, .not_turning
ld a, STEP_TURN
call .DoStep
ld a, 2
scf
ret
.not_turning
xor a
ret
.TryStep:
; Surfing actually calls .TrySurf directly instead of passing through here.
ld a, [wPlayerState]
cp PLAYER_SURF
jr z, .TrySurf
cp PLAYER_SURF_PIKA
jr z, .TrySurf
call .CheckLandPerms
jr c, .bump
call .CheckNPC
and a
jr z, .bump
cp 2
jr z, .bump
ld a, [wPlayerStandingTile]
call CheckIceTile
jr nc, .ice
; Downhill riding is slower when not moving down.
call .BikeCheck
jr nz, .walk
ld hl, wBikeFlags
bit BIKEFLAGS_DOWNHILL_F, [hl]
jr z, .fast
ld a, [wWalkingDirection]
cp DOWN
jr z, .fast
ld a, STEP_WALK
call .DoStep
scf
ret
.fast
ld a, STEP_BIKE
call .DoStep
scf
ret
.walk
ld a, STEP_WALK
call .DoStep
scf
ret
.ice
ld a, STEP_ICE
call .DoStep
scf
ret
; unused
xor a
ret
.bump
xor a
ret
.TrySurf:
call .CheckSurfPerms
ld [wd040], a
jr c, .surf_bump
call .CheckNPC
ld [wd03f], a
and a
jr z, .surf_bump
cp 2
jr z, .surf_bump
ld a, [wd040]
and a
jr nz, .ExitWater
ld a, STEP_WALK
call .DoStep
scf
ret
.ExitWater:
call .GetOutOfWater
call PlayMapMusic
ld a, STEP_WALK
call .DoStep
ld a, 6
scf
ret
.surf_bump
xor a
ret
.TryJump:
ld a, [wPlayerStandingTile]
ld e, a
and $f0
cp HI_NYBBLE_LEDGES
jr nz, .DontJump
ld a, e
and 7
ld e, a
ld d, 0
ld hl, .data_8021e
add hl, de
ld a, [wFacingDirection]
and [hl]
jr z, .DontJump
ld de, SFX_JUMP_OVER_LEDGE
call PlaySFX
ld a, STEP_LEDGE
call .DoStep
ld a, 7
scf
ret
.DontJump:
xor a
ret
.data_8021e
db FACE_RIGHT ; COLL_HOP_RIGHT
db FACE_LEFT ; COLL_HOP_LEFT
db FACE_UP ; COLL_HOP_UP
db FACE_DOWN ; COLL_HOP_DOWN
db FACE_RIGHT | FACE_DOWN ; COLL_HOP_DOWN_RIGHT
db FACE_DOWN | FACE_LEFT ; COLL_HOP_DOWN_LEFT
db FACE_UP | FACE_RIGHT ; COLL_HOP_UP_RIGHT
db FACE_UP | FACE_LEFT ; COLL_HOP_UP_LEFT
.CheckWarp:
; Bug: Since no case is made for STANDING here, it will check
; [.edgewarps + $ff]. This resolves to $3e at $8035a.
; This causes wd041 to be nonzero when standing on tile $3e,
; making bumps silent.
ld a, [wWalkingDirection]
; cp STANDING
; jr z, .not_warp
ld e, a
ld d, 0
ld hl, .EdgeWarps
add hl, de
ld a, [wPlayerStandingTile]
cp [hl]
jr nz, .not_warp
ld a, 1
ld [wd041], a
ld a, [wWalkingDirection]
; This is in the wrong place.
cp STANDING
jr z, .not_warp
ld e, a
ld a, [wPlayerDirection]
rrca
rrca
maskbits NUM_DIRECTIONS
cp e
jr nz, .not_warp
call WarpCheck
jr nc, .not_warp
call .StandInPlace
scf
ld a, 1
ret
.not_warp
xor a
ret
.EdgeWarps:
db COLL_WARP_CARPET_DOWN
db COLL_WARP_CARPET_UP
db COLL_WARP_CARPET_LEFT
db COLL_WARP_CARPET_RIGHT
.DoStep:
ld e, a
ld d, 0
ld hl, .Steps
add hl, de
add hl, de
ld a, [hli]
ld h, [hl]
ld l, a
ld a, [wWalkingDirection]
ld e, a
cp STANDING
jp z, .StandInPlace
add hl, de
ld a, [hl]
ld [wMovementAnimation], a
ld hl, .FinishFacing
add hl, de
ld a, [hl]
ld [wPlayerTurningDirection], a
ld a, 4
ret
.Steps:
dw .SlowStep
dw .NormalStep
dw .FastStep
dw .JumpStep
dw .SlideStep
dw .TurningStep
dw .BackJumpStep
dw .FinishFacing
.SlowStep:
slow_step DOWN
slow_step UP
slow_step LEFT
slow_step RIGHT
.NormalStep:
step DOWN
step UP
step LEFT
step RIGHT
.FastStep:
big_step DOWN
big_step UP
big_step LEFT
big_step RIGHT
.JumpStep:
jump_step DOWN
jump_step UP
jump_step LEFT
jump_step RIGHT
.SlideStep:
fast_slide_step DOWN
fast_slide_step UP
fast_slide_step LEFT
fast_slide_step RIGHT
.BackJumpStep:
jump_step UP
jump_step DOWN
jump_step RIGHT
jump_step LEFT
.TurningStep:
turn_step DOWN
turn_step UP
turn_step LEFT
turn_step RIGHT
.FinishFacing:
db $80 + DOWN
db $80 + UP
db $80 + LEFT
db $80 + RIGHT
.StandInPlace:
ld a, 0
ld [wPlayerTurningDirection], a
ld a, movement_step_sleep
ld [wMovementAnimation], a
xor a
ret
._WalkInPlace:
ld a, 0
ld [wPlayerTurningDirection], a
ld a, movement_step_bump
ld [wMovementAnimation], a
xor a
ret
.CheckForced:
; When sliding on ice, input is forced to remain in the same direction.
call CheckStandingOnIce
ret nc
ld a, [wPlayerTurningDirection]
cp 0
ret z
maskbits NUM_DIRECTIONS
ld e, a
ld d, 0
ld hl, .forced_dpad
add hl, de
ld a, [wCurInput]
and BUTTONS
or [hl]
ld [wCurInput], a
ret
.forced_dpad
db D_DOWN, D_UP, D_LEFT, D_RIGHT
.GetAction:
; Poll player input and update movement info.
ld hl, .action_table
ld de, .action_table_1_end - .action_table_1
ld a, [wCurInput]
bit D_DOWN_F, a
jr nz, .d_down
bit D_UP_F, a
jr nz, .d_up
bit D_LEFT_F, a
jr nz, .d_left
bit D_RIGHT_F, a
jr nz, .d_right
; Standing
jr .update
.d_down add hl, de
.d_up add hl, de
.d_left add hl, de
.d_right add hl, de
.update
ld a, [hli]
ld [wWalkingDirection], a
ld a, [hli]
ld [wFacingDirection], a
ld a, [hli]
ld [wWalkingX], a
ld a, [hli]
ld [wWalkingY], a
ld a, [hli]
ld h, [hl]
ld l, a
ld a, [hl]
ld [wWalkingTile], a
ret
player_action: MACRO
; walk direction, facing, x movement, y movement, tile collision pointer
db \1, \2, \3, \4
dw \5
ENDM
.action_table:
.action_table_1
player_action STANDING, FACE_CURRENT, 0, 0, wPlayerStandingTile
.action_table_1_end
player_action RIGHT, FACE_RIGHT, 1, 0, wTileRight
player_action LEFT, FACE_LEFT, -1, 0, wTileLeft
player_action UP, FACE_UP, 0, -1, wTileUp
player_action DOWN, FACE_DOWN, 0, 1, wTileDown
.CheckNPC:
; Returns 0 if there is an NPC in front that you can't move
; Returns 1 if there is no NPC in front
; Returns 2 if there is a movable NPC in front
ld a, 0
ldh [hMapObjectIndexBuffer], a
; Load the next X coordinate into d
ld a, [wPlayerStandingMapX]
ld d, a
ld a, [wWalkingX]
add d
ld d, a
; Load the next Y coordinate into e
ld a, [wPlayerStandingMapY]
ld e, a
ld a, [wWalkingY]
add e
ld e, a
; Find an object struct with coordinates equal to d,e
ld bc, wObjectStructs ; redundant
farcall IsNPCAtCoord
jr nc, .is_npc
call .CheckStrengthBoulder
jr c, .no_bump
xor a
ret
.is_npc
ld a, 1
ret
.no_bump
ld a, 2
ret
.CheckStrengthBoulder:
ld hl, wBikeFlags
bit BIKEFLAGS_STRENGTH_ACTIVE_F, [hl]
jr z, .not_boulder
ld hl, OBJECT_DIRECTION_WALKING
add hl, bc
ld a, [hl]
cp STANDING
jr nz, .not_boulder
ld hl, OBJECT_PALETTE
add hl, bc
bit STRENGTH_BOULDER_F, [hl]
jr z, .not_boulder
ld hl, OBJECT_FLAGS2
add hl, bc
set 2, [hl]
ld a, [wWalkingDirection]
ld d, a
ld hl, OBJECT_RANGE
add hl, bc
ld a, [hl]
and %11111100
or d
ld [hl], a
scf
ret
.not_boulder
xor a
ret
.CheckLandPerms:
; Return 0 if walking onto land and tile permissions allow it.
; Otherwise, return carry.
ld a, [wTilePermissions]
ld d, a
ld a, [wFacingDirection]
and d
jr nz, .NotWalkable
ld a, [wWalkingTile]
call .CheckWalkable
jr c, .NotWalkable
xor a
ret
.NotWalkable:
scf
ret
.CheckSurfPerms:
; Return 0 if moving in water, or 1 if moving onto land.
; Otherwise, return carry.
ld a, [wTilePermissions]
ld d, a
ld a, [wFacingDirection]
and d
jr nz, .NotSurfable
ld a, [wWalkingTile]
call .CheckSurfable
jr c, .NotSurfable
and a
ret
.NotSurfable:
scf
ret
.BikeCheck:
ld a, [wPlayerState]
cp PLAYER_BIKE
ret z
cp PLAYER_SKATE
ret
.CheckWalkable:
; Return 0 if tile a is land. Otherwise, return carry.
call GetTileCollision
and a ; LANDTILE?
ret z
scf
ret
.CheckSurfable:
; Return 0 if tile a is water, or 1 if land.
; Otherwise, return carry.
call GetTileCollision
cp WATERTILE
jr z, .Water
; Can walk back onto land from water.
and a ; LANDTILE?
jr z, .Land
jr .Neither
.Water:
xor a
ret
.Land:
ld a, 1
and a
ret
.Neither:
scf
ret
.BumpSound:
call CheckSFX
ret c
ld de, SFX_BUMP
call PlaySFX
ret
.GetOutOfWater:
push bc
ld a, PLAYER_NORMAL
ld [wPlayerState], a
call ReplaceKrisSprite ; UpdateSprites
pop bc
ret
CheckStandingOnIce::
ld a, [wPlayerTurningDirection]
cp 0
jr z, .not_ice
cp $f0
jr z, .not_ice
ld a, [wPlayerStandingTile]
call CheckIceTile
jr nc, .yep
ld a, [wPlayerState]
cp PLAYER_SKATE
jr nz, .not_ice
.yep
scf
ret
.not_ice
and a
ret
StopPlayerForEvent::
ld hl, wPlayerNextMovement
ld a, movement_step_sleep
cp [hl]
ret z
ld [hl], a
ld a, 0
ld [wPlayerTurningDirection], a
ret