minigameXdoor.asm

; Converts minigame locked doors (sprite 04E) to function as they do on SNES.

; Warning: this exactly replaces the vanilla sprite 04E init, no bytes to spare

.gba
.open "sma3.gba", "sma3test-minigameXdoor.gba", 0x08000000

.org 0x080D5CE4
LockedDoor_Init:
.org 0x080D5C64
XDoor_Init:

.org 0x080D5D48
.area @AreaEnd-org()
    cmp r0,0x0          ;\
    bne @Unlocked       ;| replaced code, saves 2 bytes
    mov r0,r4           ;|
    bl LockedDoor_Init  ;|
    b @Return           ;/
@Unlocked:
; convert to X door and move 0x10 pixels downward
    mov r1,0x01         ; sprite 001: X door
    strh r1,[r4,0x32]   ; set sprite ID
    ldr r0,[r4,0x4]
    lsl r1,r1,0xC       ; r1 = 0x1000 (saves 2 bytes by shifting the sprite ID)
    add r0,r1
    str r0,[r4,0x4]     ; set Y position
; call sprite 001 init
    mov r0,r4
    bl XDoor_Init
@Return:
    pop {r4,pc}         ; compact return, saves 4 bytes

    .fill @AreaEnd-org()
.endarea
.org 0x080D5D68
@AreaEnd:

.close