Avalon: Routine at C2F8

C2F8: Set up RIGHT vertical wall/floor connector graphics

Used by the routine at C2C2.
The left wall/floor connector has been set up already at C1C0
C2F8	LD A,$07	Graphic type = 7 (RIGHT corner wall section)
C2FA	LD ($EB43),A	Graphic type = 7 (RIGHT corner wall section)
C2FD	LD A,$30	Graphic vertical position within current room, in pixels, from top of room playing area (fixed value for all rooms).
C2FF	LD ($EB4A),A
C302	LD A,$05	Item properties byte. Default = 5 - bit 0 set means item is visible, bit 2 set means item will need erasing (e.g. before re-drawing again)
C304	LD ($EB4E),A
Calculate horizontal position of graphic within room - this will depend on the size of the room. The room's first data byte (from the set at 61A9) indicates the room size, and is used to calculate the horizontal position of the right corner section.
C307	LD A,($EB7C)	Get the 1st data byte for the room (at 61A9)
C30A	DEC A	The value is in half-character (4 pixel) steps; to calculate this, decrement the value twice
C30B	DEC A
C30C	RLA	...and multiply by 8
C30D	RLA
C30E	RLA
C30F	AND $F8	Filter off any carry bits (it will be a multiple of 8 so we don't need bits 0-2)
C311	LD ($EB48),A	...and store.
C314	LD A,$01	Graphics frame offset (= no offset)
C316	LD ($EB50),A	Graphics frame offset (= no offset)
C319	LD C,$12	Graphic number in graphics address pointer table at 97C3, this offset points to graphic address 97E5
C31B	LD A,($EB77)	Level type graphics pointer offset (for 0 for 'brick' levels, 12 for 'cavern levels')
C31E	ADD A,C	Add to graphic address pointer offset
C31F	CALL $E0C2	Set up graphics
C322	CALL $E0B0	Copy the 16 bytes of calculated data from EB43 to a bank in the room item data sets at 7C00
C325	LD HL,($EABE)	Retrieve address pointer after the above 16 bytes have been copied
C328	LD (HL),$FF	Set the first byte of the next data bank to 255 (end-of-data)
C32A	LD HL,($DAEE)	Retrieve address pointer to the room item data sets at 7C00