Nightshade: Routine at D9A3

D9A3: Update Village Item

The routine for objects of type 30 to 3F, the items that appear in the village (see SpawnItem). An item wanders about at random while the player stays in the cell that it appeared in, and is picked up when the player touches it. It turns into a burst, and goes back to the items that are available, when the player has gone from the cell or is dead.
UpdateVillageItem	D9A3	LD A,($BC8E)	Jump to UpdateVillageItem_Dead if the player is not there (the type of the player is not 10 to 2F).
	D9A6	SUB $10
	D9A8	CP $20
	D9AA	JR NC,UpdateVillageItem_Dead
	D9AC	LD A,($BC90)	Jump to UpdateVillageItem_Left if the player is not in the column of the item.
	D9AF	CP (IX+$02)
	D9B2	JR NZ,UpdateVillageItem_Left
	D9B4	LD A,($BC92)	Jump to UpdateVillageItem_Left if the player is not in the row of the item.
	D9B7	CP (IX+$04)
	D9BA	JR NZ,UpdateVillageItem_Left
	D9BC	LD B,$04	Use 04 bits for the velocity.
	D9BE	CALL ChooseRandomVelocity	Choose a random velocity.
	D9C1	CALL SetDirectionFromVelocity	Set the direction that the item is facing from its velocity.
	D9C4	CALL MoveObject	Move the item.
	D9C7	CALL NextSpriteNumber	Change the sprite of the item.
	D9CA	CALL CheckPlayerCollision	Return if the item is not touching the player.
	D9CD	RET NC	Return if the item is not touching the player.
	D9CE	CALL PickUpItem	Pick up the item.
	D9D1	LD (IX+$00),$0C	Turn the item into a burst and return.
	D9D5	RET	Turn the item into a burst and return.
The player is dead.
UpdateVillageItem_Dead	D9D6	LD (IX+$00),$0D	Turn the item into a burst, with a different sprite, and jump to UpdateVillageItem_Return.
	D9DA	JR UpdateVillageItem_Return
The player has left the cell.
UpdateVillageItem_Left	D9DC	LD (IX+$00),$0C	Turn the item into a burst.
Add the item to the items that are available for the kind of tile.
UpdateVillageItem_Return	D9E0	LD C,(IX+$05)	Fetch the kind of tile that the item was found on.
	D9E3	LD B,$00	Fetch the kind of tile that the item was found on.
	D9E5	LD HL,$BBCE	Point at the number of items for the kind of tile.
	D9E8	ADD HL,BC	Point at the number of items for the kind of tile.
	D9E9	INC (HL)	Add one to the number of items that are available.
	D9EA	RET	Return.