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; ---------------------------------------------------------------------------
; Subroutine to load level boundaries and start locations
; ---------------------------------------------------------------------------
; ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
LevelSizeLoad:
moveq #0,d0
move.b d0,($FFFFF740).w
move.b d0,($FFFFF741).w
move.b d0,($FFFFF746).w
move.b d0,($FFFFF748).w
move.b d0,(v_dle_routine).w
move.w (v_zone).w,d0
lsl.b #6,d0
lsr.w #4,d0
move.w d0,d1
add.w d0,d0
add.w d1,d0
lea LevelSizeArray(pc,d0.w),a0 ; load level boundaries
move.w (a0)+,d0
move.w d0,($FFFFF730).w
move.l (a0)+,d0
move.l d0,(v_limitleft2).w
move.l d0,(v_limitleft1).w
move.l (a0)+,d0
move.l d0,(v_limittop2).w
move.l d0,(v_limittop1).w
move.w (v_limitleft2).w,d0
addi.w #$240,d0
move.w d0,(v_limitleft3).w
move.w #$1010,($FFFFF74A).w
move.w (a0)+,d0
move.w d0,(v_lookshift).w
bra.w LevSz_ChkLamp
; ===========================================================================
; ---------------------------------------------------------------------------
; Level size array
; ---------------------------------------------------------------------------
LevelSizeArray:
; GHZ
dc.w $0004, $0000, $24BF, $0000, $0300, $0060
dc.w $0004, $0000, $1EBF, $0000, $0300, $0060
dc.w $0004, $0000, $2960, $0000, $0300, $0060
dc.w $0004, $0000, $2ABF, $0000, $0300, $0060
; LZ
dc.w $0004, $0000, $19BF, $0000, $0530, $0060
dc.w $0004, $0000, $10AF, $0000, $0720, $0060
dc.w $0004, $0000, $202F, $FF00, $0800, $0060
dc.w $0004, $0000, $20BF, $0000, $0720, $0060
; MZ
dc.w $0004, $0000, $17BF, $0000, $01D0, $0060
dc.w $0004, $0000, $17BF, $0000, $0520, $0060
dc.w $0004, $0000, $1800, $0000, $0720, $0060
dc.w $0004, $0000, $16BF, $0000, $0720, $0060
; SLZ
dc.w $0004, $0000, $1FBF, $0000, $0640, $0060
dc.w $0004, $0000, $1FBF, $0000, $0640, $0060
dc.w $0004, $0000, $2000, $0000, $06C0, $0060
dc.w $0004, $0000, $3EC0, $0000, $0720, $0060
; SYZ
dc.w $0004, $0000, $22C0, $0000, $0420, $0060
dc.w $0004, $0000, $28C0, $0000, $0520, $0060
dc.w $0004, $0000, $2C00, $0000, $0620, $0060
dc.w $0004, $0000, $2EC0, $0000, $0620, $0060
; SBZ
dc.w $0004, $0000, $21C0, $0000, $0720, $0060
dc.w $0004, $0000, $1E40, $FF00, $0800, $0060
dc.w $0004, $2080, $2460, $0510, $0510, $0060
dc.w $0004, $0000, $3EC0, $0000, $0720, $0060
zonewarning LevelSizeArray,$30
; Ending
dc.w $0004, $0000, $0500, $0110, $0110, $0060
dc.w $0004, $0000, $0DC0, $0110, $0110, $0060
dc.w $0004, $0000, $2FFF, $0000, $0320, $0060
dc.w $0004, $0000, $2FFF, $0000, $0320, $0060
; ---------------------------------------------------------------------------
; Ending start location array
; ---------------------------------------------------------------------------
EndingStLocArray:
include "_inc/Start Location Array - Ending.asm"
; ===========================================================================
LevSz_ChkLamp:
tst.b (v_lastlamp).w ; have any lampposts been hit?
beq.s LevSz_StartLoc ; if not, branch
jsr (Lamp_LoadInfo).l
move.w (v_player+obX).w,d1
move.w (v_player+obY).w,d0
bra.s LevSz_SkipStartPos
; ===========================================================================
LevSz_StartLoc:
move.w (v_zone).w,d0
lsl.b #6,d0
lsr.w #4,d0
lea StartLocArray(pc,d0.w),a1 ; load Sonic's start location
tst.w (f_demo).w ; is ending demo mode on?
bpl.s LevSz_SonicPos ; if not, branch
move.w (v_creditsnum).w,d0
subq.w #1,d0
lsl.w #2,d0
lea EndingStLocArray(pc,d0.w),a1 ; load Sonic's start location
LevSz_SonicPos:
moveq #0,d1
move.w (a1)+,d1
move.w d1,(v_player+obX).w ; set Sonic's position on x-axis
moveq #0,d0
move.w (a1),d0
move.w d0,(v_player+obY).w ; set Sonic's position on y-axis
SetScreen:
LevSz_SkipStartPos:
subi.w #160,d1 ; is Sonic more than 160px from left edge?
bcc.s SetScr_WithinLeft ; if yes, branch
moveq #0,d1
SetScr_WithinLeft:
move.w (v_limitright2).w,d2
cmp.w d2,d1 ; is Sonic inside the right edge?
bcs.s SetScr_WithinRight ; if yes, branch
move.w d2,d1
SetScr_WithinRight:
move.w d1,(v_screenposx).w ; set horizontal screen position
subi.w #96,d0 ; is Sonic within 96px of upper edge?
bcc.s SetScr_WithinTop ; if yes, branch
moveq #0,d0
SetScr_WithinTop:
cmp.w (v_limitbtm2).w,d0 ; is Sonic above the bottom edge?
blt.s SetScr_WithinBottom ; if yes, branch
move.w (v_limitbtm2).w,d0
SetScr_WithinBottom:
move.w d0,(v_screenposy).w ; set vertical screen position
bsr.w BgScrollSpeed
moveq #0,d0
move.b (v_zone).w,d0
lsl.b #2,d0
move.l LoopTileNums(pc,d0.w),(v_256loop1).w
rts
; ===========================================================================
; ---------------------------------------------------------------------------
; Sonic start location array
; ---------------------------------------------------------------------------
StartLocArray: include "_inc/Start Location Array - Levels.asm"
; ---------------------------------------------------------------------------
; Which 256x256 tiles contain loops or roll-tunnels
; ---------------------------------------------------------------------------
LoopTileNums:
; loop loop tunnel tunnel
dc.b $B5, $7F, $1F, $20 ; Green Hill
dc.b $7F, $7F, $7F, $7F ; Labyrinth
dc.b $7F, $7F, $7F, $7F ; Marble
dc.b $AA, $B4, $7F, $7F ; Star Light
dc.b $7F, $7F, $7F, $7F ; Spring Yard
dc.b $7F, $7F, $7F, $7F ; Scrap Brain
zonewarning LoopTileNums,4
dc.b $7F, $7F, $7F, $7F ; Ending (Green Hill)
even
; ---------------------------------------------------------------------------
; Subroutine to set scroll speed of some backgrounds
; ---------------------------------------------------------------------------
; ||||||||||||||| S U B R O U T I N E |||||||||||||||||||||||||||||||||||||||
BgScrollSpeed:
tst.b (v_lastlamp).w
bne.s loc_6206
move.w d0,(v_bgscreenposy).w
move.w d0,(v_bg2screenposy).w
move.w d1,(v_bgscreenposx).w
move.w d1,(v_bg2screenposx).w
move.w d1,(v_bg3screenposx).w
loc_6206:
moveq #0,d2
move.b (v_zone).w,d2
add.w d2,d2
move.w BgScroll_Index(pc,d2.w),d2
jmp BgScroll_Index(pc,d2.w)
; End of function BgScrollSpeed
; ===========================================================================
BgScroll_Index: dc.w BgScroll_GHZ-BgScroll_Index, BgScroll_LZ-BgScroll_Index
dc.w BgScroll_MZ-BgScroll_Index, BgScroll_SLZ-BgScroll_Index
dc.w BgScroll_SYZ-BgScroll_Index, BgScroll_SBZ-BgScroll_Index
zonewarning BgScroll_Index,2
dc.w BgScroll_End-BgScroll_Index
; ===========================================================================
BgScroll_GHZ:
clr.l (v_bgscreenposx).w
clr.l (v_bgscreenposy).w
clr.l (v_bg2screenposy).w
clr.l (v_bg3screenposy).w
lea ($FFFFA800).w,a2
clr.l (a2)+
clr.l (a2)+
clr.l (a2)+
rts
; ===========================================================================
BgScroll_LZ:
asr.l #1,d0
move.w d0,(v_bgscreenposy).w
rts
; ===========================================================================
BgScroll_MZ:
rts
; ===========================================================================
BgScroll_SLZ:
asr.l #1,d0
addi.w #$C0,d0
move.w d0,(v_bgscreenposy).w
clr.l (v_bgscreenposx).w
rts
; ===========================================================================
BgScroll_SYZ:
asl.l #4,d0
move.l d0,d2
asl.l #1,d0
add.l d2,d0
asr.l #8,d0
addq.w #1,d0
move.w d0,(v_bgscreenposy).w
clr.l (v_bgscreenposx).w
rts
; ===========================================================================
BgScroll_SBZ:
andi.w #$7F8,d0
asr.w #3,d0
addq.w #1,d0
move.w d0,(v_bgscreenposy).w
rts
; ===========================================================================
BgScroll_End:
move.w (v_screenposx).w,d0
asr.w #1,d0
move.w d0,(v_bgscreenposx).w
move.w d0,(v_bg2screenposx).w
asr.w #2,d0
move.w d0,d1
add.w d0,d0
add.w d1,d0
move.w d0,(v_bg3screenposx).w
clr.l (v_bgscreenposy).w
clr.l (v_bg2screenposy).w
clr.l (v_bg3screenposy).w
lea ($FFFFA800).w,a2
clr.l (a2)+
clr.l (a2)+
clr.l (a2)+
rts
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