Dun Darach: Routine at 94A8

94A8: Handle description string control values.

Used by the routine at Bg_CalcAndDraw.

Input

Output

The follow are control codes that can exist within a description string.

Bg_StrCtrlCodes

94A8

LD A,(IX+$00)

check for 'skip' value, if not check for other values.

94AB

AND $F0

94AD

CP $00

94AF

JR NZ,Bg_StrCtrlCodes_0

94B1

XOR (IX+$00)

String value means skip by the number of column units.

94B4

LD E,A

94B5

LD D,$00

94B7

LD HL,(Bg_ColumnsLeft)

94BA

SBC HL,DE

94BC

JR C,Bg_BlitItemEnd

94BE

JP Bg_CalcAndDraw_13

Bg_StrCtrlCodes_0

94C1

CP $10

Reverse image value.

94C3

JR NZ,Bg_StrCtrlCodes_1

94C5

LD A,$80

94C7

LD (_92d8_ReverseBit),A

94CA

INC IX

94CC

POP BC

94CD

DEC C

94CE

JP NZ,Bg_CalcAndDraw_11

94D1

RET

Bg_StrCtrlCodes_1

94D2

CP $20

94D4

JR NZ,Bg_StrCtrlCodes_2

94D6

POP BC

94D7

XOR (IX+$00)

94DA

LD B,A

94DB

DEC C

94DC

RET Z

94DD

INC IX

94DF

LD ($92D9),IX

94E3

LD ($92DB),BC

94E7

JP Bg_CalcAndDraw_11

Bg_StrCtrlCodes_2

94EA

CP $60

94EC

JR NZ,Bg_StrCtrlCodes_3

94EE

XOR (IX+$00)

94F1

LD (Draw_RoomObjectBmpIndex),A

94F4

LD HL,(Bg_ColumnsLeft)

94F7

LD ($92E3),HL

94FA

JP Bg_CalcAndDraw_14

Bg_StrCtrlCodes_3

94FD

JP Bg_BlitItemEnd

Ignore any unknown codes by ending the walking of string.