mirror of https://github.com/pret/pokecrystal.git
215 lines
3.2 KiB
NASM
215 lines
3.2 KiB
NASM
CalcMagikarpLength: ; fbbfc
|
|
; Return Magikarp's length (in mm) at MagikarpLength (big endian).
|
|
;
|
|
; input:
|
|
; de: EnemyMonDVs
|
|
; bc: PlayerID
|
|
|
|
; This function is poorly commented.
|
|
|
|
; In short, it generates a value between 190 and 1786 using
|
|
; a Magikarp's DVs and its trainer ID. This value is further
|
|
; filtered in LoadEnemyMon to make longer Magikarp even rarer.
|
|
|
|
; The value is generated from a lookup table.
|
|
; The index is determined by the dv xored with the player's trainer id.
|
|
|
|
; bc = rrc(dv[0]) ++ rrc(dv[1]) ^ rrc(id)
|
|
|
|
; if bc < 10: [MagikarpLength] = c + 190
|
|
; if bc >= $ff00: [MagikarpLength] = c + 1370
|
|
; else: [MagikarpLength] = z * 100 + (bc - x) / y
|
|
|
|
; X, Y, and Z depend on the value of b as follows:
|
|
|
|
; if b = 0: x = 310, y = 2, z = 3
|
|
; if b = 1: x = 710, y = 4, z = 4
|
|
; if b = 2-9: x = 2710, y = 20, z = 5
|
|
; if b = 10-29: x = 7710, y = 50, z = 6
|
|
; if b = 30-68: x = 17710, y = 100, z = 7
|
|
; if b = 69-126: x = 32710, y = 150, z = 8
|
|
; if b = 127-185: x = 47710, y = 150, z = 9
|
|
; if b = 186-224: x = 57710, y = 100, z = 10
|
|
; if b = 225-243: x = 62710, y = 50, z = 11
|
|
; if b = 244-251: x = 64710, y = 20, z = 12
|
|
; if b = 252-253: x = 65210, y = 5, z = 13
|
|
; if b = 254: x = 65410, y = 2, z = 14
|
|
|
|
|
|
; bc = rrc(dv[0]) ++ rrc(dv[1]) ^ rrc(id)
|
|
|
|
; id
|
|
ld h, b
|
|
ld l, c
|
|
ld a, [hli]
|
|
ld b, a
|
|
ld c, [hl]
|
|
rrc b
|
|
rrc c
|
|
|
|
; dv
|
|
ld a, [de]
|
|
inc de
|
|
rrca
|
|
rrca
|
|
xor b
|
|
ld b, a
|
|
|
|
ld a, [de]
|
|
rrca
|
|
rrca
|
|
xor c
|
|
ld c, a
|
|
|
|
; if bc < 10:
|
|
; de = bc + 190
|
|
; break
|
|
|
|
ld a, b
|
|
and a
|
|
jr nz, .no
|
|
ld a, c
|
|
cp 10
|
|
jr nc, .no
|
|
|
|
ld hl, 190
|
|
add hl, bc
|
|
ld d, h
|
|
ld e, l
|
|
jr .done
|
|
|
|
.no
|
|
|
|
ld hl, .Lengths
|
|
ld a, 2
|
|
ld [wd265], a
|
|
|
|
.read
|
|
ld a, [hli]
|
|
ld e, a
|
|
ld a, [hli]
|
|
ld d, a
|
|
call .BCLessThanDE
|
|
jr nc, .next
|
|
|
|
; c = (bc - de) / [hl]
|
|
call .BCMinusDE
|
|
ld a, b
|
|
ld [hDividend + 0], a
|
|
ld a, c
|
|
ld [hDividend + 1], a
|
|
ld a, [hl]
|
|
ld [hDivisor], a
|
|
ld b, 2
|
|
call Divide
|
|
ld a, [hQuotient + 2]
|
|
ld c, a
|
|
|
|
; de = c + 100 * (2 + i)
|
|
xor a
|
|
ld [hMultiplicand + 0], a
|
|
ld [hMultiplicand + 1], a
|
|
ld a, 100
|
|
ld [hMultiplicand + 2], a
|
|
ld a, [wd265]
|
|
ld [hMultiplier], a
|
|
call Multiply
|
|
ld b, 0
|
|
ld a, [hProduct + 3]
|
|
add c
|
|
ld e, a
|
|
ld a, [hProduct + 2]
|
|
adc b
|
|
ld d, a
|
|
jr .done
|
|
|
|
.next
|
|
inc hl ; align to next triplet
|
|
ld a, [wd265]
|
|
inc a
|
|
ld [wd265], a
|
|
cp 16
|
|
jr c, .read
|
|
|
|
call .BCMinusDE
|
|
ld hl, 1600
|
|
add hl, bc
|
|
ld d, h
|
|
ld e, l
|
|
|
|
.done
|
|
; hl = de * 10
|
|
ld h, d
|
|
ld l, e
|
|
add hl, hl
|
|
add hl, hl
|
|
add hl, de
|
|
add hl, hl
|
|
|
|
; hl = hl / 254
|
|
ld de, -254
|
|
ld a, -1
|
|
.div_254
|
|
inc a
|
|
add hl, de
|
|
jr c, .div_254
|
|
|
|
; d, e = hl / 12, hl % 12
|
|
ld d, 0
|
|
.mod_12
|
|
cp 12
|
|
jr c, .ok
|
|
sub 12
|
|
inc d
|
|
jr .mod_12
|
|
.ok
|
|
ld e, a
|
|
|
|
ld hl, MagikarpLength
|
|
ld [hl], d
|
|
inc hl
|
|
ld [hl], e
|
|
ret
|
|
; fbc9a
|
|
|
|
.BCLessThanDE: ; fbc9a
|
|
; Intention: Return bc < de.
|
|
; Reality: Return b < d.
|
|
ld a, b
|
|
cp d
|
|
ret c
|
|
ret nc ; whoops
|
|
ld a, c
|
|
cp e
|
|
ret
|
|
; fbca1
|
|
|
|
.BCMinusDE: ; fbca1
|
|
; bc -= de
|
|
ld a, c
|
|
sub e
|
|
ld c, a
|
|
ld a, b
|
|
sbc d
|
|
ld b, a
|
|
ret
|
|
; fbca8
|
|
|
|
.Lengths: ; fbca8
|
|
; ????, divisor
|
|
dwb 110, 1
|
|
dwb 310, 2
|
|
dwb 710, 4
|
|
dwb 2710, 20
|
|
dwb 7710, 50
|
|
dwb 17710, 100
|
|
dwb 32710, 150
|
|
dwb 47710, 150
|
|
dwb 57710, 100
|
|
dwb 62710, 50
|
|
dwb 64710, 20
|
|
dwb 65210, 5
|
|
dwb 65410, 2
|
|
dwb 65510, 1 ; not used
|
|
; fbcd2
|