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Optimize ADC and SBC instructions

refactor
Christophe Parent 2024-06-01 08:54:07 -07:00
parent fb8a5fcda3
commit 4b3dcd6d60
1 changed files with 50 additions and 92 deletions
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142
src/main.asm
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@ -1809,8 +1809,7 @@ EndGameText:
dex ; are we printing the world/lives display? dex ; are we printing the world/lives display?
bne CheckPlayerName ; if not, branch to check player's name bne CheckPlayerName ; if not, branch to check player's name
lda NumberofLives ; otherwise, check number of lives lda NumberofLives ; otherwise, check number of lives
clc ; and increment by one for display adc #$01 ; and increment by one for display (clc optimization)
adc #$01
cmp #10 ; more than 9 lives? cmp #10 ; more than 9 lives?
bcc PutLives bcc PutLives
sbc #10 ; if so, subtract 10 and put a crown tile sbc #10 ; if so, subtract 10 and put a crown tile
@ -2182,8 +2181,7 @@ SaveHAdder:
lda #$00 lda #$00
sta $05 ; initialize temp high byte sta $05 ; initialize temp high byte
lda $02 ; get vertical high nybble offset used in block buffer routine lda $02 ; get vertical high nybble offset used in block buffer routine
clc adc #$20 ; add 32 pixels for the status bar (clc optimization)
adc #$20 ; add 32 pixels for the status bar
asl asl
rol $05 ; shift and rotate d7 onto d0 and d6 into carry rol $05 ; shift and rotate d7 onto d0 and d6 into carry
asl asl
@ -4610,9 +4608,8 @@ GetAreaDataAddrs:
lda AreaPointer ; mask out all but 5 LSB lda AreaPointer ; mask out all but 5 LSB
and #%00011111 and #%00011111
sta AreaAddrsLOffset ; save as low offset sta AreaAddrsLOffset ; save as low offset
lda EnemyAddrHOffsets,y ; load base value with 2 altered MSB, lda EnemyAddrHOffsets,y ; load base value with 2 altered MSB, then add base value to 5 LSB,
clc ; then add base value to 5 LSB, result adc AreaAddrsLOffset ; result becomes offset for level data (clc optimization)
adc AreaAddrsLOffset ; becomes offset for level data
tay tay
lda EnemyDataAddrLow,y ; use offset to load pointer lda EnemyDataAddrLow,y ; use offset to load pointer
sta EnemyDataLow sta EnemyDataLow
@ -6590,9 +6587,8 @@ RghtFrict:
XSpdSign: XSpdSign:
cmp #$00 ; if player not moving or moving to the right, cmp #$00 ; if player not moving or moving to the right,
bpl SetAbsSpd ; branch and leave horizontal speed value unmodified bpl SetAbsSpd ; branch and leave horizontal speed value unmodified
eor #$ff eor #$ff ; otherwise get two's compliment to get absolute
clc ; otherwise get two's compliment to get absolute adc #$01-1 ; unsigned walking/running speed (clc optimization)
adc #$01 ; unsigned walking/running speed
SetAbsSpd: SetAbsSpd:
sta Player_XSpeedAbsolute ; store walking/running speed here and leave sta Player_XSpeedAbsolute ; store walking/running speed here and leave
rts rts
@ -6883,8 +6879,7 @@ WhirlpoolActivate:
lsr ; shift d0 into carry (to run on every other frame) lsr ; shift d0 into carry (to run on every other frame)
bcc WhPull ; if d0 not set, branch to last part of code bcc WhPull ; if d0 not set, branch to last part of code
lda $01 ; get center lda $01 ; get center
sec sbc Player_X_Position ; subtract player's horizontal coordinate (sec optimization)
sbc Player_X_Position ; subtract player's horizontal coordinate
lda $00 ; get page location of center lda $00 ; get page location of center
sbc Player_PageLoc ; subtract borrow sbc Player_PageLoc ; subtract borrow
bpl LeftWh ; if player to the left of center, branch bpl LeftWh ; if player to the left of center, branch
@ -6900,8 +6895,7 @@ LeftWh:
lsr ; shift d0 into carry lsr ; shift d0 into carry
bcc WhPull ; if d0 not set, branch bcc WhPull ; if d0 not set, branch
lda Player_X_Position ; otherwise slowly pull player right, towards the center lda Player_X_Position ; otherwise slowly pull player right, towards the center
clc adc #$01-1 ; add one pixel (clc optimization)
adc #$01 ; add one pixel
sta Player_X_Position ; set player's new horizontal coordinate sta Player_X_Position ; set player's new horizontal coordinate
lda Player_PageLoc lda Player_PageLoc
adc #$00 ; add carry adc #$00 ; add carry
@ -7156,8 +7150,7 @@ FireCannon:
lda Cannon_X_Position,y ; get horizontal coordinate of cannon lda Cannon_X_Position,y ; get horizontal coordinate of cannon
sta Enemy_X_Position,x ; save as horizontal coordinate of bullet bill sta Enemy_X_Position,x ; save as horizontal coordinate of bullet bill
lda Cannon_Y_Position,y ; get vertical coordinate of cannon lda Cannon_Y_Position,y ; get vertical coordinate of cannon
sec sbc #$08-1 ; subtract eight pixels (because enemies are 24 pixels tall) (sec optimization)
sbc #$08 ; subtract eight pixels (because enemies are 24 pixels tall)
sta Enemy_Y_Position,x ; save as vertical coordinate of bullet bill sta Enemy_Y_Position,x ; save as vertical coordinate of bullet bill
lda #$01 lda #$01
sta Enemy_Y_HighPos,x ; set vertical high byte of bullet bill sta Enemy_Y_HighPos,x ; set vertical high byte of bullet bill
@ -7283,8 +7276,7 @@ ProcHammerObj:
beq SetHSpd ; if currently at 2, branch beq SetHSpd ; if currently at 2, branch
bcs SetHPos ; if greater than 2, branch elsewhere bcs SetHPos ; if greater than 2, branch elsewhere
txa txa
clc ; add 13 bytes to use adc #$0d ; add 13 bytes to use proper misc object (clc optimization)
adc #$0d ; proper misc object
tax ; return offset to X tax ; return offset to X
lda #$10 lda #$10
sta $00 ; set downward movement force sta $00 ; set downward movement force
@ -7309,8 +7301,7 @@ SetHSpd:
SetHPos: SetHPos:
dec Misc_State,x ; decrement hammer's state dec Misc_State,x ; decrement hammer's state
lda Enemy_X_Position,y ; get enemy's horizontal position lda Enemy_X_Position,y ; get enemy's horizontal position
clc adc #$02-1 ; set position 2 pixels to the right (clc optimization)
adc #$02 ; set position 2 pixels to the right
sta Misc_X_Position,x ; store as hammer's horizontal position sta Misc_X_Position,x ; store as hammer's horizontal position
lda Enemy_PageLoc,y ; get enemy's page location lda Enemy_PageLoc,y ; get enemy's page location
adc #$00 ; add carry adc #$00 ; add carry
@ -8739,8 +8730,7 @@ CreateSpiny:
lda #$01 ; put spiny within vertical screen unit lda #$01 ; put spiny within vertical screen unit
sta Enemy_Y_HighPos,x sta Enemy_Y_HighPos,x
lda Enemy_Y_Position,y ; put spiny eight pixels above where lakitu is lda Enemy_Y_Position,y ; put spiny eight pixels above where lakitu is
sec sbc #$08 ; (sec optimization)
sbc #$08
sta Enemy_Y_Position,x sta Enemy_Y_Position,x
lda PseudoRandomBitReg,x ; get 2 LSB of LSFR and save to Y lda PseudoRandomBitReg,x ; get 2 LSB of LSFR and save to Y
and #%00000011 and #%00000011
@ -8872,8 +8862,7 @@ MaxCC:
asl ; otherwise, multiply A by 2 asl ; otherwise, multiply A by 2
GSeed: GSeed:
pha ; save to stack pha ; save to stack
clc adc $00 ; add to last two bits of LSFR we saved earlier (clc optimization)
adc $00 ; add to last two bits of LSFR we saved earlier
sta $00 ; save it there sta $00 ; save it there
lda PseudoRandomBitReg+1,x lda PseudoRandomBitReg+1,x
and #%00000011 ; if neither of the last two bits of second LSFR set, and #%00000011 ; if neither of the last two bits of second LSFR set,
@ -8883,8 +8872,7 @@ GSeed:
sta $00 ; third LSFR part sta $00 ; third LSFR part
RSeed: RSeed:
pla ; get value from stack we saved earlier pla ; get value from stack we saved earlier
clc adc $01 ; add to last two bits of LSFR we saved in other place (clc optimization)
adc $01 ; add to last two bits of LSFR we saved in other place
tay ; use as pseudorandom offset here tay ; use as pseudorandom offset here
lda FlyCCXSpeedData,y ; get horizontal speed using pseudorandom offset lda FlyCCXSpeedData,y ; get horizontal speed using pseudorandom offset
sta Enemy_X_Speed,x sta Enemy_X_Speed,x
@ -8897,9 +8885,8 @@ RSeed:
and #%00000010 and #%00000010
beq D2XPos1 ; if d1 not set, branch beq D2XPos1 ; if d1 not set, branch
lda Enemy_X_Speed,x lda Enemy_X_Speed,x
eor #$ff ; if d1 set, change horizontal speed eor #$ff ; if d1 set, change horizontal speed into two's compliment,
clc ; into two's compliment, thus moving in the opposite adc #$01 ; thus moving in the opposite direction (clc optimization)
adc #$01 ; direction
sta Enemy_X_Speed,x sta Enemy_X_Speed,x
inc Enemy_MovingDir,x ; increment to move towards the left inc Enemy_MovingDir,x ; increment to move towards the left
D2XPos1: D2XPos1:
@ -9022,8 +9009,7 @@ PutAtRightExtent:
SpawnFromMouth: SpawnFromMouth:
lda Enemy_X_Position,y ; get bowser's horizontal position lda Enemy_X_Position,y ; get bowser's horizontal position
sec sbc #$0e ; subtract 14 pixels (sec optimization)
sbc #$0e ; subtract 14 pixels
sta Enemy_X_Position,x ; save as flame's horizontal position sta Enemy_X_Position,x ; save as flame's horizontal position
lda Enemy_PageLoc,y lda Enemy_PageLoc,y
sta Enemy_PageLoc,x ; copy page location from bowser to flame sta Enemy_PageLoc,x ; copy page location from bowser to flame
@ -9077,9 +9063,8 @@ StarFChk:
lda Enemy_ID,y ; check for presence of star flag object lda Enemy_ID,y ; check for presence of star flag object
cmp #StarFlagObject ; if there isn't a star flag object, cmp #StarFlagObject ; if there isn't a star flag object,
bne StarFChk ; routine goes into infinite loop = crash bne StarFChk ; routine goes into infinite loop = crash
lda Enemy_X_Position,y lda Enemy_X_Position,y ; get horizontal coordinate of star flag object, then
sec ; get horizontal coordinate of star flag object, then sbc #$30 ; subtract 48 pixels from it and save to (sec optimization)
sbc #$30 ; subtract 48 pixels from it and save to
pha ; the stack pha ; the stack
lda Enemy_PageLoc,y lda Enemy_PageLoc,y
sbc #$00 ; subtract the carry from the page location sbc #$00 ; subtract the carry from the page location
@ -9198,8 +9183,7 @@ FireBulletBill:
HandleGroupEnemies: HandleGroupEnemies:
ldy #$00 ; load value for green koopa troopa ldy #$00 ; load value for green koopa troopa
sec sbc #$37-1 ; subtract $37 from second byte read (sec optimization)
sbc #$37 ; subtract $37 from second byte read
pha ; save result in stack for now pha ; save result in stack for now
cmp #$04 ; was byte in $3b-$3e range? cmp #$04 ; was byte in $3b-$3e range?
bcs SnglID ; if so, branch bcs SnglID ; if so, branch
@ -9243,8 +9227,7 @@ GSltLp:
sta Enemy_PageLoc,x ; store page location for enemy object sta Enemy_PageLoc,x ; store page location for enemy object
lda $03 lda $03
sta Enemy_X_Position,x ; store x coordinate for enemy object sta Enemy_X_Position,x ; store x coordinate for enemy object
clc adc #$18 ; add 24 pixels for next enemy (clc optimization)
adc #$18 ; add 24 pixels for next enemy
sta $03 sta $03
lda $02 ; add carry to page location for lda $02 ; add carry to page location for
adc #$00 ; next enemy adc #$00 ; next enemy
@ -9270,8 +9253,7 @@ InitPiranhaPlant:
sta PiranhaPlant_MoveFlag,x ; be used as vertical speed, but not in this case sta PiranhaPlant_MoveFlag,x ; be used as vertical speed, but not in this case
lda Enemy_Y_Position,x lda Enemy_Y_Position,x
sta PiranhaPlantDownYPos,x ; save original vertical coordinate here sta PiranhaPlantDownYPos,x ; save original vertical coordinate here
sec sbc #$18 ; (sec optimization)
sbc #$18
sta PiranhaPlantUpYPos,x ; save original vertical coordinate - 24 pixels here sta PiranhaPlantUpYPos,x ; save original vertical coordinate - 24 pixels here
lda #$09 lda #$09
jmp SetBBox2 ; set specific value for bounding box control jmp SetBBox2 ; set specific value for bounding box control
@ -9440,10 +9422,10 @@ CommonSmallLift:
;-------------------------------- ;--------------------------------
PlatPosDataLow: PlatPosDataLow:
.byte $08,$0c,$f8 .byte $08, $0c, $f8
PlatPosDataHigh: PlatPosDataHigh:
.byte $00,$00,$ff .byte $00, $00, $ff
PosPlatform: PosPlatform:
lda Enemy_X_Position,x ; get horizontal coordinate lda Enemy_X_Position,x ; get horizontal coordinate
@ -10016,8 +9998,7 @@ ProcSwimmingB:
pla ; pull 3 LSB of frame counter from the stack pla ; pull 3 LSB of frame counter from the stack
bne BSwimE ; branch to leave, execute code only every eighth frame bne BSwimE ; branch to leave, execute code only every eighth frame
lda Enemy_Y_MoveForce,x lda Enemy_Y_MoveForce,x
clc ; add to movement force to speed up swim adc #$01 ; add to movement force to speed up swim (clc optimization)
adc #$01
sta Enemy_Y_MoveForce,x ; set movement force sta Enemy_Y_MoveForce,x ; set movement force
sta BlooperMoveSpeed,x ; set as movement speed sta BlooperMoveSpeed,x ; set as movement speed
cmp #$02 cmp #$02
@ -10030,8 +10011,7 @@ SlowSwim:
pla ; pull 3 LSB of frame counter from the stack pla ; pull 3 LSB of frame counter from the stack
bne NoSSw ; branch to leave, execute code only every eighth frame bne NoSSw ; branch to leave, execute code only every eighth frame
lda Enemy_Y_MoveForce,x lda Enemy_Y_MoveForce,x
sec ; subtract from movement force to slow swim sbc #$01 ; subtract from movement force to slow swim (sec optimization)
sbc #$01
sta Enemy_Y_MoveForce,x ; set movement force sta Enemy_Y_MoveForce,x ; set movement force
sta BlooperMoveSpeed,x ; set as movement speed sta BlooperMoveSpeed,x ; set as movement speed
bne NoSSw ; if any speed, branch to leave bne NoSSw ; if any speed, branch to leave
@ -10211,8 +10191,7 @@ SusFbar:
cmp #$18 cmp #$18
bne SetupGFB ; if not at twenty-four branch to not change bne SetupGFB ; if not at twenty-four branch to not change
SkpFSte: SkpFSte:
clc adc #$01-1 ; add one to spinning thing to avoid horizontal state (clc optimization)
adc #$01 ; add one to spinning thing to avoid horizontal state
sta FirebarSpinState_High,x sta FirebarSpinState_High,x
SetupGFB: SetupGFB:
sta $ef ; save high byte of spinning thing, modified or otherwise sta $ef ; save high byte of spinning thing, modified or otherwise
@ -10275,8 +10254,7 @@ AddHA:
sbc $06 ; original one and skip this part sbc $06 ; original one and skip this part
jmp ChkFOfs jmp ChkFOfs
SubtR1: SubtR1:
sec ; subtract original X from the sbc Enemy_Rel_XPos ; subtract original X from the current sprite X (sec optimization)
sbc Enemy_Rel_XPos ; current sprite X
ChkFOfs: ChkFOfs:
cmp #$59 ; if difference of coordinates within a certain range, cmp #$59 ; if difference of coordinates within a certain range,
bcc VAHandl ; continue by handling vertical adder bcc VAHandl ; continue by handling vertical adder
@ -10337,8 +10315,7 @@ ChkVFBD:
cmp #$f0 ; because, really, what's the point? cmp #$f0 ; because, really, what's the point?
bcs Chk2Ofs bcs Chk2Ofs
lda Sprite_X_Position+4 ; get OAM X coordinate for sprite #1 lda Sprite_X_Position+4 ; get OAM X coordinate for sprite #1
clc adc #$04 ; add four pixels (clc optimization)
adc #$04 ; add four pixels
sta $04 ; store here sta $04 ; store here
sec ; subtract horizontal coordinate of firebar sec ; subtract horizontal coordinate of firebar
sbc $06 ; from the X coordinate of player's sprite 1 sbc $06 ; from the X coordinate of player's sprite 1
@ -10387,33 +10364,28 @@ GetFirebarPosition:
cmp #$09 cmp #$09
bcc GetHAdder ; if lower than $09, branch ahead bcc GetHAdder ; if lower than $09, branch ahead
eor #%00001111 ; otherwise get two's compliment to oscillate eor #%00001111 ; otherwise get two's compliment to oscillate
clc adc #$01-1 ; (clc optimization)
adc #$01
GetHAdder: GetHAdder:
sta $01 ; store result, modified or not, here sta $01 ; store result, modified or not, here
ldy $00 ; load number of firebar ball where we're at ldy $00 ; load number of firebar ball where we're at
lda FirebarTblOffsets,y ; load offset to firebar position data lda FirebarTblOffsets,y ; load offset to firebar position data
clc adc $01 ; add oscillated high byte of spinstate (clc optimization)
adc $01 ; add oscillated high byte of spinstate
tay ; to offset here and use as new offset tay ; to offset here and use as new offset
lda FirebarPosLookupTbl,y ; get data here and store as horizontal adder lda FirebarPosLookupTbl,y ; get data here and store as horizontal adder
sta $01 sta $01
pla ; pull whatever was in A from the stack pla ; pull whatever was in A from the stack
pha ; save it again because we still need it pha ; save it again because we still need it
clc adc #$08 ; add eight this time, to get vertical adder (clc optimization)
adc #$08 ; add eight this time, to get vertical adder
and #%00001111 ; mask out high nybble and #%00001111 ; mask out high nybble
cmp #$09 ; if lower than $09, branch ahead cmp #$09 ; if lower than $09, branch ahead
bcc GetVAdder bcc GetVAdder
eor #%00001111 ; otherwise get two's compliment eor #%00001111 ; otherwise get two's compliment
clc adc #$01-1 ; (clc optimization)
adc #$01
GetVAdder: GetVAdder:
sta $02 ; store result here sta $02 ; store result here
ldy $00 ldy $00
lda FirebarTblOffsets,y ; load offset to firebar position data again lda FirebarTblOffsets,y ; load offset to firebar position data again
clc adc $02 ; this time add value in $02 to offset here and use as offset (clc optimization)
adc $02 ; this time add value in $02 to offset here and use as offset
tay tay
lda FirebarPosLookupTbl,y ; get data here and store as vertica adder lda FirebarPosLookupTbl,y ; get data here and store as vertica adder
sta $02 sta $02
@ -10460,8 +10432,7 @@ AddCCF:
cmp #$08 ; if result or two's compliment greater than eight, cmp #$08 ; if result or two's compliment greater than eight,
bcs BPGet ; skip to the end without changing movement force bcs BPGet ; skip to the end without changing movement force
lda Enemy_Y_MoveForce,x lda Enemy_Y_MoveForce,x
clc adc #$10 ; otherwise add to it (clc optimization)
adc #$10 ; otherwise add to it
sta Enemy_Y_MoveForce,x sta Enemy_Y_MoveForce,x
lsr ; move high nybble to low again lsr ; move high nybble to low again
lsr lsr
@ -11262,8 +11233,7 @@ ChkToMoveBalPlat:
lda PlatformCollisionFlag,x ; get collision flag lda PlatformCollisionFlag,x ; get collision flag
bpl ColFlg ; branch if collision bpl ColFlg ; branch if collision
lda Enemy_Y_MoveForce,x lda Enemy_Y_MoveForce,x
clc ; add $05 to contents of moveforce, whatever they be adc #$05 ; add $05 to contents of moveforce, whatever they be (clc optimization)
adc #$05
sta $00 ; store here sta $00 ; store here
lda Enemy_Y_Speed,x lda Enemy_Y_Speed,x
adc #$00 ; add carry to vertical speed adc #$00 ; add carry to vertical speed
@ -11386,8 +11356,7 @@ GetLRp:
pla ; get second/third copy of vertical speed from stack pla ; get second/third copy of vertical speed from stack
bpl GetHRp ; skip this part if moving downwards or not at all bpl GetHRp ; skip this part if moving downwards or not at all
txa txa
clc adc #$08 ; add eight to vertical coordinate (clc optimization) and
adc #$08 ; add eight to vertical coordinate and
tax ; save as X tax ; save as X
GetHRp: GetHRp:
txa ; move vertical coordinate to A txa ; move vertical coordinate to A
@ -11796,8 +11765,7 @@ PlayerHammerCollision:
sta Misc_Collision_Flag,x ; otherwise set collision flag now sta Misc_Collision_Flag,x ; otherwise set collision flag now
lda Misc_X_Speed,x lda Misc_X_Speed,x
eor #$ff ; get two's compliment of eor #$ff ; get two's compliment of
clc ; hammer's horizontal speed adc #$01-1 ; hammer's horizontal speed (clc optimization)
adc #$01
sta Misc_X_Speed,x ; set to send hammer flying the opposite direction sta Misc_X_Speed,x ; set to send hammer flying the opposite direction
lda StarInvincibleTimer ; if star mario invincibility timer set, lda StarInvincibleTimer ; if star mario invincibility timer set,
bne ExPHC ; branch to leave bne ExPHC ; branch to leave
@ -11958,8 +11926,7 @@ ChkInj:
cmp #Bloober cmp #Bloober
bcc ChkETmrs bcc ChkETmrs
lda Player_Y_Position ; add 12 pixels to player's vertical position lda Player_Y_Position ; add 12 pixels to player's vertical position
clc adc #$0c-1 ; (clc optimization)
adc #$0c
cmp Enemy_Y_Position,x ; compare modified player's position to enemy's position cmp Enemy_Y_Position,x ; compare modified player's position to enemy's position
bcc EnemyStomped ; branch if this player's position above (less than) enemy's bcc EnemyStomped ; branch if this player's position above (less than) enemy's
ChkETmrs: ChkETmrs:
@ -12082,8 +12049,7 @@ HandleStompedShellE:
sta Enemy_State,x sta Enemy_State,x
inc StompChainCounter ; increment the stomp counter inc StompChainCounter ; increment the stomp counter
lda StompChainCounter ; add whatever is in the stomp counter lda StompChainCounter ; add whatever is in the stomp counter
clc ; to whatever is in the stomp timer adc StompTimer ; to whatever is in the stomp timer (clc optimization)
adc StompTimer
jsr SetupFloateyNumber ; award points accordingly jsr SetupFloateyNumber ; award points accordingly
inc StompTimer ; increment stomp timer of some sort inc StompTimer ; increment stomp timer of some sort
ldy PrimaryHardMode ; check primary hard mode flag ldy PrimaryHardMode ; check primary hard mode flag
@ -12350,8 +12316,7 @@ ChkSmallPlatLoop:
MoveBoundBox: MoveBoundBox:
lda BoundingBox_UL_YPos,y ; move bounding box vertical coordinates lda BoundingBox_UL_YPos,y ; move bounding box vertical coordinates
clc ; 128 pixels downwards adc #$80 ; 128 pixels downwards (clc optimization)
adc #$80
sta BoundingBox_UL_YPos,y sta BoundingBox_UL_YPos,y
lda BoundingBox_DR_YPos,y lda BoundingBox_DR_YPos,y
clc clc
@ -12369,9 +12334,8 @@ ProcSPlatCollisions:
ldx ObjectOffset ; return enemy object buffer offset to X, then continue ldx ObjectOffset ; return enemy object buffer offset to X, then continue
ProcLPlatCollisions: ProcLPlatCollisions:
lda BoundingBox_DR_YPos,y ; get difference by subtracting the top lda BoundingBox_DR_YPos,y ; get difference by subtracting the top of the player's bounding box
sec ; of the player's bounding box from the bottom sbc BoundingBox_UL_YPos ; from the bottom of the platform's bounding box (sec optimization)
sbc BoundingBox_UL_YPos ; of the platform's bounding box
cmp #$04 ; if difference too large or negative, cmp #$04 ; if difference too large or negative,
bcs ChkForTopCollision ; branch, do not alter vertical speed of player bcs ChkForTopCollision ; branch, do not alter vertical speed of player
lda Player_Y_Speed ; check to see if player's vertical speed is moving down lda Player_Y_Speed ; check to see if player's vertical speed is moving down
@ -12442,8 +12406,7 @@ PositionPlayerOnVPlat:
ldy Enemy_Y_HighPos,x ldy Enemy_Y_HighPos,x
cpy #$01 ; if vertical high byte offscreen, skip this cpy #$01 ; if vertical high byte offscreen, skip this
bne ExPlPos bne ExPlPos
sec ; subtract 32 pixels from vertical coordinate sbc #$20 ; subtract 32 pixels from vertical coordinate for the player object's height (sec optimization)
sbc #$20 ; for the player object's height
sta Player_Y_Position ; save as player's new vertical coordinate sta Player_Y_Position ; save as player's new vertical coordinate
tya tya
sbc #$00 ; subtract borrow and store as player's sbc #$00 ; subtract borrow and store as player's
@ -13145,7 +13108,7 @@ LandEnemyProperly:
and #%01000000 ; branch if d6 in enemy state is set and #%01000000 ; branch if d6 in enemy state is set
bne LandEnemyInitState bne LandEnemyInitState
lda Enemy_State,x lda Enemy_State,x
bpl ChkLandedEnemyState ; branch if d7 in enemy state is not set bpl ChkLandedEnemyState ; branch if d7 in enemy state is not set
SChkA: SChkA:
jmp DoEnemySideCheck ; if lower nybble < $0d, d7 set but d6 not set, jump here jmp DoEnemySideCheck ; if lower nybble < $0d, d7 set but d6 not set, jump here
@ -13308,8 +13271,7 @@ EnemyJump:
jsr SubtEnemyYPos ; do a sub here jsr SubtEnemyYPos ; do a sub here
bcc DoSide ; if enemy vertical coord + 62 < 68, branch to leave bcc DoSide ; if enemy vertical coord + 62 < 68, branch to leave
lda Enemy_Y_Speed,x lda Enemy_Y_Speed,x
clc ; add two to vertical speed adc #$02-1 ; add two to vertical speed (clc optimization)
adc #$02
cmp #$03 ; if green paratroopa not falling, branch ahead cmp #$03 ; if green paratroopa not falling, branch ahead
bcc DoSide bcc DoSide
jsr ChkUnderEnemy ; otherwise, check to see if green paratroopa is jsr ChkUnderEnemy ; otherwise, check to see if green paratroopa is
@ -13661,8 +13623,7 @@ BlockBufferChk_Enemy:
BlockBufferChk_FBall: BlockBufferChk_FBall:
ldy #$1a ; set offset for block buffer adder data ldy #$1a ; set offset for block buffer adder data
txa txa
clc adc #$07-1 ; add seven bytes to use (clc optimization)
adc #$07 ; add seven bytes to use
tax tax
lda #$00 ; set A to return vertical coordinate lda #$00 ; set A to return vertical coordinate
BBChk_E: BBChk_E:
@ -14101,8 +14062,7 @@ JCoinGfxHandler:
bcs DrawFloateyNumber_Coin ; branch to draw floatey number bcs DrawFloateyNumber_Coin ; branch to draw floatey number
lda Misc_Y_Position,x ; store vertical coordinate as lda Misc_Y_Position,x ; store vertical coordinate as
sta Sprite_Y_Position,y ; Y coordinate for first sprite sta Sprite_Y_Position,y ; Y coordinate for first sprite
clc adc #$08 ; add eight pixels (clc optimization)
adc #$08 ; add eight pixels
sta Sprite_Y_Position+4,y ; store as Y coordinate for second sprite sta Sprite_Y_Position+4,y ; store as Y coordinate for second sprite
lda Misc_Rel_XPos ; get relative horizontal coordinate lda Misc_Rel_XPos ; get relative horizontal coordinate
sta Sprite_X_Position,y sta Sprite_X_Position,y
@ -14402,8 +14362,7 @@ ChkRearSte:
and #%00100000 ; if bowser not defeated, do not set flag and #%00100000 ; if bowser not defeated, do not set flag
beq DrawBowser beq DrawBowser
lda $02 ; subtract 16 pixels from lda $02 ; subtract 16 pixels from
sec ; saved vertical coordinate sbc #$10 ; saved vertical coordinate (sec optimization)
sbc #$10
sta $02 sta $02
jmp FlipBowserOver ; jump to set vertical flip flag jmp FlipBowserOver ; jump to set vertical flip flag
@ -14577,9 +14536,8 @@ CheckForVerticalFlip:
cmp #$15 cmp #$15
bcs FlipEnemyVertically ; also branch if enemy object => $15 bcs FlipEnemyVertically ; also branch if enemy object => $15
txa txa
clc
adc #$08 ; if not selected objects or => $15, set adc #$08 ; if not selected objects or => $15, set
tax ; offset in X for next row tax ; offset in X for next row (clc optimization)
FlipEnemyVertically: FlipEnemyVertically:
lda Sprite_Tilenumber,x ; load first or second row tiles lda Sprite_Tilenumber,x ; load first or second row tiles