island-story/src/player.s

INCLUDE "hardware.inc"
INCLUDE "input.inc"

Section "Player Data", WRAM0

playerWorldX: dw
playerWorldY: dw

Section "Player Code", ROM0

spriteData:
    INCBIN "png/player.2bpp"

Player_Init::
    ld a, 8
    ld hl, _OAM + 1
    ld [hl], a

    ld bc, _VRAM8000
    ld hl, spriteData
    ld d, 16
    call memcpy

    ld hl, _OAM
    ld a, 144-8
    ld [hli], a
    ld a, 8
    ld [hli], a
    xor a
    ld [hli], a
    ld [hli], a

    ld bc, _OAMRAM
    ld hl, _OAM
    ld d, 4
    call memcpy

    ret

Player_Update::
    ; Only update every 2 frames
    ld hl, frame
    ld a, [hl]
    and %1
    cp %1
    jr nz, .done

    ld hl, keys
    ld b, [hl]

    ; check for move right
    ld a, b
    and BTN_RIGHT
    jr z, .left

    ; check for right boundary
    ld hl, _OAM + 1
    ld a, [hl]
    cp 160
    jr nc, .done

    ; Update x-position and set x-flip = false
    inc [hl]
    ld hl, _OAM + 3
    res 5, [hl]

.left:
    ; check for left button
    ld a, b
    and BTN_LEFT
    jr z, .done

    ; check for left boundary
    ld hl, _OAM + 1
    ld a, [hl]
    cp 9
    jr c, .done

    ; Update x-position and set x-flip = true
    dec [hl]
    ld hl, _OAM + 3
    set 5, [hl]

.done:
    ret