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;
; Player bullets
;
bullet_player_new:
    call entities_new
    bnc
    ret

    ; a : x points to the entity

    ld y, ET_BULLET
    ld [a : x], y

    inc x
    bo
    inc a

    ; caller entity is in the stack
    ld y, [sp + 4]
    ld b, [sp + 5]

    inc y
    bo
    inc b
    push y
    ld y, [b : y]
    ; same x
    ld [a : x], y
    pop y

    inc x
    bo
    inc a

    inc y
    bo
    inc b
    ld y, [b : y]
    ; same y
    ld [a : x], y

    inc x
    bo
    inc a

    ; frame 0
    ld y, 0
    ld [a : x], y 

    inc x
    bo
    inc a

    ; player bullet sprite
    ld y, <pbullet_sprite
    ld [a : x], y
    inc x
    bo
    inc a
    ld y, >pbullet_sprite
    ld [a : x], y

    inc x
    bo
    inc b

    ; update function
    ld y, <pbullet_update
    ld [a : x], y
    inc x
    bo
    inc a
    ld y, >pbullet_update
    ld [a : x], y

    ret

pbullet_update:
    ld x, [sp + 2]
    ld a, [sp + 3]

    add x, 2
    bo
    inc a

    ld y, [a : x]
    sub y, 2
    bo
    jmp pbullet_done
    ld [a : x], y
    ret

pbullet_done:
    ld x, [sp + 2]
    ld a, [sp + 3]

    ld y, ET_NONE
    ld [a : x], y
    ret