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|
CanObjectMoveInDirection:
ld hl, OBJECT_PALETTE
add hl, bc
bit SWIMMING_F, [hl]
jr z, .not_swimming
ld hl, OBJECT_FLAGS1
add hl, bc
bit NOCLIP_TILES_F, [hl] ; lost, uncomment next line to fix
; jr nz, .noclip_tiles
push hl
push bc
call WillObjectBumpIntoLand
pop bc
pop hl
ret c
jr .continue
.not_swimming
ld hl, OBJECT_FLAGS1
add hl, bc
bit NOCLIP_TILES_F, [hl]
jr nz, .noclip_tiles
push hl
push bc
call WillObjectBumpIntoWater
pop bc
pop hl
ret c
.noclip_tiles
.continue
bit NOCLIP_OBJS_F, [hl]
jr nz, .noclip_objs
push hl
push bc
call WillObjectBumpIntoSomeoneElse
pop bc
pop hl
ret c
.noclip_objs
bit MOVE_ANYWHERE_F, [hl]
jr nz, .move_anywhere
push hl
call HasObjectReachedMovementLimit
pop hl
ret c
push hl
call IsObjectMovingOffEdgeOfScreen
pop hl
ret c
.move_anywhere
and a
ret
WillObjectBumpIntoWater:
call CanObjectLeaveTile
ret c
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld d, [hl]
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld e, [hl]
ld hl, OBJECT_PALETTE
add hl, bc
bit OAM_PRIORITY, [hl]
jp nz, WillObjectRemainOnWater
ld hl, OBJECT_NEXT_TILE
add hl, bc
ld a, [hl]
ld d, a
call GetTileCollision
and a ; LAND_TILE
jr z, WillObjectBumpIntoTile
scf
ret
WillObjectBumpIntoLand:
call CanObjectLeaveTile
ret c
ld hl, OBJECT_NEXT_TILE
add hl, bc
ld a, [hl]
call GetTileCollision
cp WATER_TILE
jr z, WillObjectBumpIntoTile
scf
ret
WillObjectBumpIntoTile:
ld hl, OBJECT_NEXT_TILE
add hl, bc
ld a, [hl]
call GetSideWallDirectionMask
ret nc
push af
ld hl, OBJECT_DIRECTION_WALKING
add hl, bc
ld a, [hl]
maskbits NUM_DIRECTIONS
ld e, a
ld d, 0
ld hl, .dir_masks
add hl, de
pop af
and [hl]
ret z
scf
ret
.dir_masks
db DOWN_MASK ; DOWN
db UP_MASK ; UP
db RIGHT_MASK ; LEFT
db LEFT_MASK ; RIGHT
CanObjectLeaveTile:
ld hl, OBJECT_STANDING_TILE
add hl, bc
ld a, [hl]
call GetSideWallDirectionMask
ret nc
push af
ld hl, OBJECT_DIRECTION_WALKING
add hl, bc
maskbits NUM_DIRECTIONS
ld e, a
ld d, 0
ld hl, .dir_masks
add hl, de
pop af
and [hl]
ret z
scf
ret
.dir_masks
db UP_MASK ; DOWN
db DOWN_MASK ; UP
db LEFT_MASK ; LEFT
db RIGHT_MASK ; RIGHT
GetSideWallDirectionMask:
ld d, a
and $f0
cp HI_NYBBLE_SIDE_WALLS
jr z, .continue
cp HI_NYBBLE_SIDE_BUOYS
jr z, .continue
xor a
ret
.continue
ld a, d
and $7
ld e, a
ld d, 0
ld hl, .side_wall_masks
add hl, de
ld a, [hl]
scf
ret
.side_wall_masks
db RIGHT_MASK ; COLL_RIGHT_WALL/BUOY
db LEFT_MASK ; COLL_LEFT_WALL/BUOY
db DOWN_MASK ; COLL_UP_WALL/BUOY
db UP_MASK ; COLL_DOWN_WALL/BUOY
db UP_MASK | RIGHT_MASK ; COLL_DOWN_RIGHT_WALL/BUOY
db UP_MASK | LEFT_MASK ; COLL_DOWN_LEFT_WALL/BUOY
db DOWN_MASK | RIGHT_MASK ; COLL_UP_RIGHT_WALL/BUOY
db DOWN_MASK | LEFT_MASK ; COLL_UP_LEFT_WALL/BUOY
WillObjectRemainOnWater:
ld hl, OBJECT_DIRECTION_WALKING
add hl, bc
ld a, [hl]
maskbits NUM_DIRECTIONS
jr z, .down
dec a
jr z, .up
dec a
jr z, .left
jr .right
.down
inc e
push de
inc d
jr .continue
.up
push de
inc d
jr .continue
.left
push de
inc e
jr .continue
.right
inc d
push de
inc e
.continue
call GetCoordTile
call GetTileCollision
pop de
and a ; LAND_TILE
jr nz, .not_land
call GetCoordTile
call GetTileCollision
and a ; LAND_TILE
jr nz, .not_land
xor a
ret
.not_land
scf
ret
CheckFacingObject::
call GetFacingTileCoord
; Double the distance for counter tiles.
call CheckCounterTile
jr nz, .not_counter
ld a, [wPlayerStandingMapX]
sub d
cpl
inc a
add d
ld d, a
ld a, [wPlayerStandingMapY]
sub e
cpl
inc a
add e
ld e, a
.not_counter
ld bc, wObjectStructs ; redundant
ld a, 0
ldh [hMapObjectIndex], a
call IsNPCAtCoord
ret nc
ld hl, OBJECT_DIRECTION_WALKING
add hl, bc
ld a, [hl]
cp STANDING
jr z, .standing
xor a
ret
.standing
scf
ret
WillObjectBumpIntoSomeoneElse:
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld d, [hl]
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld e, [hl]
jr IsNPCAtCoord
IsObjectFacingSomeoneElse: ; unreferenced
ldh a, [hMapObjectIndex]
call GetObjectStruct
call .GetFacingCoords
call IsNPCAtCoord
ret
.GetFacingCoords:
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld d, [hl]
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld e, [hl]
call GetSpriteDirection
and a ; OW_DOWN?
jr z, .down
cp OW_UP
jr z, .up
cp OW_LEFT
jr z, .left
; OW_RIGHT
inc d
ret
.down
inc e
ret
.up
dec e
ret
.left
dec d
ret
IsNPCAtCoord:
ld bc, wObjectStructs
xor a
.loop
ldh [hObjectStructIndex], a
call DoesObjectHaveASprite
jr z, .next
ld hl, OBJECT_FLAGS1
add hl, bc
bit 7, [hl]
jr nz, .next
ld hl, OBJECT_PALETTE
add hl, bc
bit BIG_OBJECT_F, [hl]
jr z, .not_big
call WillObjectIntersectBigObject
jr nc, .check_current_coords
jr .continue
.not_big
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld a, [hl]
cp d
jr nz, .check_current_coords
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld a, [hl]
cp e
jr nz, .check_current_coords
.continue
ldh a, [hMapObjectIndex]
ld l, a
ldh a, [hObjectStructIndex]
cp l
jr nz, .yes
.check_current_coords
ld hl, OBJECT_MAP_X
add hl, bc
ld a, [hl]
cp d
jr nz, .next
ld hl, OBJECT_MAP_Y
add hl, bc
ld a, [hl]
cp e
jr nz, .next
ldh a, [hMapObjectIndex]
ld l, a
ldh a, [hObjectStructIndex]
cp l
jr nz, .yes
.next
ld hl, OBJECT_LENGTH
add hl, bc
ld b, h
ld c, l
ldh a, [hObjectStructIndex]
inc a
cp NUM_OBJECT_STRUCTS
jr nz, .loop
and a
ret
.yes
scf
ret
HasObjectReachedMovementLimit:
ld hl, OBJECT_RADIUS
add hl, bc
ld a, [hl]
and a
jr z, .nope
and $f
jr z, .check_y
ld e, a
ld d, a
ld hl, OBJECT_INIT_X
add hl, bc
ld a, [hl]
sub d
ld d, a
ld a, [hl]
add e
ld e, a
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld a, [hl]
cp d
jr z, .yes
cp e
jr z, .yes
.check_y
ld hl, OBJECT_RADIUS
add hl, bc
ld a, [hl]
swap a
and $f
jr z, .nope
ld e, a
ld d, a
ld hl, OBJECT_INIT_Y
add hl, bc
ld a, [hl]
sub d
ld d, a
ld a, [hl]
add e
ld e, a
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld a, [hl]
cp d
jr z, .yes
cp e
jr z, .yes
.nope
xor a
ret
.yes
scf
ret
IsObjectMovingOffEdgeOfScreen:
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld a, [wXCoord]
cp [hl]
jr z, .check_y
jr nc, .yes
add $9
cp [hl]
jr c, .yes
.check_y
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld a, [wYCoord]
cp [hl]
jr z, .nope
jr nc, .yes
add $8
cp [hl]
jr c, .yes
.nope
and a
ret
.yes
scf
ret
IsNPCAtPlayerCoord: ; unreferenced
ld a, [wPlayerStandingMapX]
ld d, a
ld a, [wPlayerStandingMapY]
ld e, a
ld bc, wObjectStructs
xor a
.loop
ldh [hObjectStructIndex], a
call DoesObjectHaveASprite
jr z, .next
ld hl, OBJECT_MOVEMENTTYPE
add hl, bc
ld a, [hl]
cp SPRITEMOVEDATA_BIGDOLLSYM
jr nz, .not_big
call WillObjectIntersectBigObject
jr c, .yes
jr .next
.not_big
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld a, [hl]
cp e
jr nz, .check_current_coords
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld a, [hl]
cp d
jr nz, .check_current_coords
ldh a, [hObjectStructIndex]
cp PLAYER_OBJECT
jr z, .next
jr .yes
.check_current_coords
ld hl, OBJECT_MAP_Y
add hl, bc
ld a, [hl]
cp e
jr nz, .next
ld hl, OBJECT_MAP_X
add hl, bc
ld a, [hl]
cp d
jr nz, .next
jr .yes
.next
ld hl, OBJECT_LENGTH
add hl, bc
ld b, h
ld c, l
ldh a, [hObjectStructIndex]
inc a
cp NUM_OBJECT_STRUCTS
jr nz, .loop
xor a
ret
.yes
scf
ret
WillObjectIntersectBigObject:
ld hl, OBJECT_NEXT_MAP_X
add hl, bc
ld a, d
sub [hl]
jr c, .nope
cp 2 ; big doll width
jr nc, .nope
ld hl, OBJECT_NEXT_MAP_Y
add hl, bc
ld a, e
sub [hl]
jr c, .nope
cp 2 ; big doll height
jr nc, .nope
scf
ret
.nope
and a
ret
|
