Multi-Midway Points for UberASM

HEADER
LOROM

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;Defines
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	!RAM_MIDWAY	= $7FB800	; holds which midway point to use (96 bytes, one for each level)

ORG $05D8BC
	autoclean JML MAIN		;Point to new routine
	BRA $01 : NOP

ORG $05D9DE
	autoclean JML SECONDARIES2	; additional code for secondary exits

ORG $048F74
	autoclean JML RESET_MIDWAY	; hijack the code that resets the midway point

ORG $00A19A
	autoclean JML MIDWAY_INIT	; hijack the OW initialization to reset the table

ORG $05DAA3
	autoclean JML NO_YOSHI		; make secondary exits compatible with no yoshi intros


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;New main code
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freecode

!MIDWAY_NUMBER	= $0002	; max number of midway points per level
			; using more vastly increases the size of the table
			; if you changed it to, for example, 0003
			; the tables for EVERY level would look similar to this:
			; dw $0001 : dw $0001 : dw $0001
			; the maximum of midway points would be 00FF (256 decimal)


LEVEL_TABLES:
;levels 0-F
dw $0000 : dw $0000		;
dw $0001 : dw $0001		; place the level number which you want to use here
dw $0002 : dw $0002		;
dw $0003 : dw $0003		; IE: $0140 will use level 140's midway entrance
dw $0004 : dw $0004		; $00FF will use level 0FF's midway entrance
dw $0005 : dw $0005		; $0100 will use level 100's
dw $0006 : dw $0006		; ect
dw $0007 : dw $0007
dw $0008 : dw $0008
dw $0009 : dw $0009		; setting the highest nybble (making it 1000+ )
dw $000A : dw $000A		; will use a secondary entrance instead
dw $000B : dw $000B		; IE: $1003 will use secondary entrance 003
dw $000C : dw $000C		; $1138 will use secondary entrance 138
dw $000D : dw $000D		; $1000 will use secondary entrance 000
dw $000E : dw $000E		; ect
dw $000F : dw $000F
;levels 10-1F
dw $0010 : dw $0010
dw $0011 : dw $0011
dw $0012 : dw $0012
dw $0013 : dw $0013
dw $0014 : dw $0014
dw $0015 : dw $0015
dw $0016 : dw $0016
dw $0017 : dw $0017
dw $0018 : dw $0018
dw $0019 : dw $0019
dw $001A : dw $001A
dw $001B : dw $001B
dw $001C : dw $001C
dw $001D : dw $001D
dw $001E : dw $001E
dw $001F : dw $001F
;levels 20-24
dw $0020 : dw $0020
dw $0021 : dw $0021
dw $0022 : dw $0022
dw $0023 : dw $0023
dw $0024 : dw $0024
;levels 101-10F
dw $0101 : dw $0101
dw $0102 : dw $0102
dw $0103 : dw $0103
dw $0104 : dw $0104
dw $11CA : dw $0105
dw $0106 : dw $0106
dw $0107 : dw $0107
dw $0108 : dw $0108
dw $0109 : dw $0109
dw $010A : dw $010A
dw $010B : dw $010B
dw $010C : dw $010C
dw $010D : dw $010D
dw $010E : dw $010E
dw $010F : dw $010F
;levels 110-11F
dw $0110 : dw $0110
dw $0111 : dw $0111
dw $0112 : dw $0112
dw $0113 : dw $0113
dw $0114 : dw $0114
dw $0115 : dw $0115
dw $0116 : dw $0116
dw $0117 : dw $0117
dw $0118 : dw $0118
dw $0119 : dw $0119
dw $011A : dw $011A
dw $011B : dw $011B
dw $011C : dw $011C
dw $011D : dw $011D
dw $011E : dw $011E
dw $011F : dw $011F
;levels 120-12F
dw $0120 : dw $0120
dw $0121 : dw $0121
dw $0122 : dw $0122
dw $0123 : dw $0123
dw $0124 : dw $0124
dw $0125 : dw $0125
dw $0126 : dw $0126
dw $0127 : dw $0127
dw $0128 : dw $0128
dw $0129 : dw $0129
dw $012A : dw $012A
dw $012B : dw $012B
dw $012C : dw $012C
dw $012D : dw $012D
dw $012E : dw $012E
dw $012F : dw $012F
;levels 130-13B
dw $0130 : dw $0130
dw $0131 : dw $0131
dw $0132 : dw $0132
dw $0133 : dw $0133
dw $0134 : dw $0134
dw $0135 : dw $0135
dw $0136 : dw $0136
dw $0137 : dw $0137
dw $0138 : dw $0138
dw $0139 : dw $0139
dw $013A : dw $013A
dw $013B : dw $013B



MAIN:
	REP #$30	; 16-bit A X Y
	LDA $0E		; (this is stolen from levelasm)
	STA $010B	;
	PHY		; push y
	SEP #$30	; 8 bit A X Y
	LDA $141A	; skip if not the opening level
	BNE RETURN
	LDA $1B93	; prevent infinite loop if using a secondary exit
	BNE RETURN
	LDY $13BF	; get translevel number
	LDA $1EA2,y	; get level settings
	AND #$40	; check midway point flag
	BEQ RETURN	; return if not set
	PHB		;
	PHK		; wrapper
	PLB		;
	TYA		; stick translevel number in A
	REP #$30	; 16 bit A X Y
	AND #$00FF	; clear high byte of A
	ASL		; x 2
	STA $0E		; store to scratch
	PHX		; push x
	TYX		; stick y in x temporarily
	LDA !RAM_MIDWAY,x	;\ get midway point number to use
	AND #$00FF		; |
	ASL			;/
	PLX		; pull x
	LDY #$0000	;
	CLC
LOOP:
	ADC $0E		; multiply it by the number of midway points in use per level
	INY
	CPY #!MIDWAY_NUMBER
	BCC LOOP
	TAY		; stick in y
	LDA LEVEL_TABLES,y	; get new level number
	CMP #$1000		; check secondary exit flag
	BCS SECONDARIES		; use secondary exit
	AND #$01FF		; failsafe
	STA $0E			; store level number
	STA $010B
	SEP #$30	; 8 bit A X Y
	PLB		; get bank back
RETURN:
	REP #$30	; 16 bit A X Y
	PLY		; pull y
	LDA $0E
	JML $05D8C3	; return

SECONDARIES:
	AND #$0FFF	; clear secondary exit flag here
	ORA #$0600	; these bits have to be set
	SEP #$30	; 8 bit A X Y
	STA $19B8	; store secondary exit number (low)
	XBA		; flip high and low byte of A
	STA $19D8	; store secondary exit number (high and properties)
	STZ $95		; set these to 0
	STZ $97
	PLB		; get bank back
	REP #$30	; 16 bit A X Y
	PLY		; pull y back
	SEP #$30	; 8 bit A X Y
	JML $05D7B3	; return and load level at a secondary exit position

SECONDARIES2:
	LDX $1B93	; check if using a secondary exit for this
	BNE RETURN2	; if so, skip the code that sets mario's x position to the midway entrance
	STA $13CF	; restore old code
	LDA $02		; restore old code
	JML $05D9E3	; return

RETURN2:
	JML $05D9EC	; return without setting mario's x to the midway entrance

RESET_MIDWAY:
	STA $1EA2,x		; restore old code
	INC $13D9		;
	LDA !RAM_MIDWAY,x
	AND #$FF00		; reset midway point number too
	STA !RAM_MIDWAY,x
	JML $048F7A		; return

MIDWAY_INIT:
	LDA $1F49,x		; restore old code
	STA $1EA2,x		;
	LDA #$00		; reset this table
	STA !RAM_MIDWAY,x
	JML $00A1A0		; return

NO_YOSHI:
	STZ $1B93	; reset this (prevents glitch with no yoshi intros and secondary entrances)
	LDA $05D78A,x	; restore old code
	JML $05DAA7	; return

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