Nightshade: Routine at C5CE

Used by the routine at StartGame.

Every sixteen frames, when the player is standing on a kind of tile that still has items to give, makes an item appear at the player's position. The item is placed in the first free one of the four objects from ObjectTable_Items, at a random position within the cell. The number of items that are left for each kind of tile is held in the table at ItemsLeft.

Used by the routine at StartGame. Every sixteen frames, when the player is standing on a kind of tile that still has items to give, makes an item appear at the player's position. The item is placed in the first free one of the four objects from ObjectTable_Items, at a random position within the cell. The number of items that are left for each kind of tile is held in the table at ItemsLeft.
Wait until it is time to spawn an item.
SpawnItem	C5CE	LD A,($BC02)	Return if the player is still materialising.
	C5D1	CP $70
	C5D3	RET NZ
	C5D4	LD A,($BBB2)	Return unless the frame counter is a multiple of sixteen.
	C5D7	AND $0F
	C5D9	RET NZ
	C5DA	LD IY,$BCCE	Start with the first of the four item objects, set the distance from one object to the next (10 bytes) and set a counter for the four items.
	C5DE	LD DE,$0010
	C5E1	LD B,$04
Find a free item object.
SpawnItem_Find	C5E3	LD A,(IY+$00)	Jump to SpawnItem_Spawn if this item object is free.
	C5E6	AND A
	C5E7	JR Z,SpawnItem_Spawn
	C5E9	ADD IY,DE	Move on to the next item object and loop back until all four have been tried, and then return.
	C5EB	DJNZ SpawnItem_Find
	C5ED	RET
Place the item in the player's cell, if the tile still has items left.
SpawnItem_Spawn	C5EE	LD A,($BC90)	Fetch the column and row of the player's cell.
	C5F1	LD L,A
	C5F2	LD A,($BC92)
	C5F5	LD H,A
	C5F6	LD E,L
	C5F7	LD D,H
	C5F8	CALL FindMapTile	Find out what kind of tile is in the cell.
	C5FB	LD C,A	Fetch the number of items that are left for this kind of tile, and return if there are none.
	C5FC	LD B,$00
	C5FE	LD HL,$BBCE
	C601	ADD HL,BC
	C602	LD A,(HL)
	C603	AND A
	C604	RET Z
	C605	DEC (HL)	Take one from the number of items that are left.
	C606	LD (IY+$02),E	Set the column and row of the item to those of the player's cell, and the tile to the kind of tile.
	C609	LD (IY+$04),D
	C60C	LD (IY+$05),C
	C60F	LD A,C	Choose the type of the item (30, 34, 38 or 3C) from the kind of tile.
	C610	AND $03
	C612	ADD A,A
	C613	ADD A,A
	C614	OR $30
	C616	LD (IY+$00),A	Make the object an item.
	C619	LD HL,($BBAA)	Put the item at a random place along the X axis of the cell.
	C61C	LD A,L
	C61D	AND $7F
	C61F	ADD A,$40
	C621	LD (IY+$01),A
	C624	LD A,H	Put the item at a random place along the Y axis of the cell.
	C625	AND $7F
	C627	ADD A,$40
	C629	LD (IY+$03),A
	C62C	LD A,$08	Make the item eight units wide and deep.
	C62E	LD (IY+$08),A
	C631	LD (IY+$09),A
	C634	LD (IY+$0C),$F8	Set the drawing offsets of the item to F8 and 04.
	C638	LD (IY+$0D),$04	Set the drawing offsets of the item to F8 and 04.
	C63C	RET	Return.