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Upload literally everything from the pokecrystal16 expand-move-ID branch

engine/overworld/player_movement.asm

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+DoPlayerMovement::
+	call .GetDPad
+	ld a, movement_step_sleep
+	ld [wMovementAnimation], a
+	xor a
+	ld [wWalkingIntoEdgeWarp], 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, [wWalkingIntoEdgeWarp]
+	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, [wPlayerTile]
+	ld c, a
+	call CheckWhirlpoolTile
+	jr c, .not_whirlpool
+	ld a, PLAYERMOVEMENT_FORCE_TURN
+	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, PLAYERMOVEMENT_CONTINUE
+	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, PLAYERMOVEMENT_TURN
+	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, [wPlayerTile]
+	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 ; unreferenced
+	xor a
+	ret
+
+.bump
+	xor a
+	ret
+
+.TrySurf:
+	call .CheckSurfPerms
+	ld [wWalkingIntoLand], a
+	jr c, .surf_bump
+
+	call .CheckNPC
+	ld [wWalkingIntoNPC], a
+	and a
+	jr z, .surf_bump
+	cp 2
+	jr z, .surf_bump
+
+	ld a, [wWalkingIntoLand]
+	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, PLAYERMOVEMENT_EXIT_WATER
+	scf
+	ret
+
+.surf_bump
+	xor a
+	ret
+
+.TryJump:
+	ld a, [wPlayerTile]
+	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, .ledge_table
+	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, PLAYERMOVEMENT_JUMP
+	scf
+	ret
+
+.DontJump:
+	xor a
+	ret
+
+.ledge_table
+	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: No bump noise if standing on tile $3E (see docs/bugs_and_glitches.md)
+
+	ld a, [wWalkingDirection]
+	ld e, a
+	ld d, 0
+	ld hl, .EdgeWarps
+	add hl, de
+	ld a, [wPlayerTile]
+	cp [hl]
+	jr nz, .not_warp
+
+	ld a, TRUE
+	ld [wWalkingIntoEdgeWarp], a
+	ld a, [wWalkingDirection]
+	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, PLAYERMOVEMENT_WARP
+	ret
+
+.not_warp
+	xor a ; PLAYERMOVEMENT_NORMAL
+	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, PLAYERMOVEMENT_FINISH
+	ret
+
+.Steps:
+; entries correspond to STEP_* constants (see constants/map_object_constants.asm)
+	table_width 2, DoPlayerMovement.Steps
+	dw .SlowStep
+	dw .NormalStep
+	dw .FastStep
+	dw .JumpStep
+	dw .SlideStep
+	dw .TurningStep
+	dw .BackJumpStep
+	dw .FinishFacing
+	assert_table_length NUM_STEPS
+
+.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
+
+MACRO player_action
+; 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, wPlayerTile
+.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. The game actually treats
+; this the same as an NPC in front (bump).
+	ld a, 0
+	ldh [hMapObjectIndex], a
+; Load the next X coordinate into d
+	ld a, [wPlayerMapX]
+	ld d, a
+	ld a, [wWalkingX]
+	add d
+	ld d, a
+; Load the next Y coordinate into e
+	ld a, [wPlayerMapY]
+	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, .no_npc
+	call .CheckStrengthBoulder
+	jr c, .no_bump
+
+	xor a ; bump
+	ret
+
+.no_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_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 ; LAND_TILE
+	ret z
+	scf
+	ret
+
+.CheckSurfable:
+; Return 0 if tile a is water, or 1 if land.
+; Otherwise, return carry.
+
+	call GetTileCollision
+	cp WATER_TILE
+	jr z, .Water
+
+; Can walk back onto land from water.
+	and a ; LAND_TILE
+	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 UpdatePlayerSprite ; UpdateSprites
+	pop bc
+	ret
+
+CheckStandingOnIce::
+	ld a, [wPlayerTurningDirection]
+	cp 0
+	jr z, .not_ice
+	cp $f0
+	jr z, .not_ice
+	ld a, [wPlayerTile]
+	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