Remove residual/unnecessary code and data

src/main.asm

@@ -74,7 +74,6 @@ FrenzyEnemyTimer      = $078f
 BowserFireBreathTimer = $0790
 StompTimer            = $0791
 AirBubbleTimer        = $0792
-ScrollIntervalTimer   = $0795
 EnemyIntervalTimer    = $0796
 BrickCoinTimer        = $079d
 InjuryTimer           = $079e
@@ -410,7 +409,6 @@ Block_BBuf_Low        = $03e6
 Block_Metatile        = $03e8
 Block_PageLoc2        = $03ea
 Block_RepFlag         = $03ec
-Block_ResidualCounter = $03f0
 Block_Orig_XPos       = $03f1
 
 BoundingBox_UL_XPos   = $04ac
@@ -428,7 +426,6 @@ FireballCounter       = $06ce
 FireballThrowingTimer = $0711
 
 HammerEnemyOffset     = $06ae
-JumpCoinMiscOffset    = $06b7
 
 Block_Buffer_1        = $0500
 Block_Buffer_2        = $05d0
@@ -906,7 +903,6 @@ ExitPause:
 ; $00 - used for preset value
 
 SpriteShuffler:
-    ldy AreaType               ; load level type, likely residual code
     lda #$28                   ; load preset value which will put it at
     sta $00                    ; sprite #10
     ldx #$0e                   ; start at the end of OAM data offsets
@@ -1086,7 +1082,6 @@ StartWorld1:
     sta OperMode_Task           ; set game mode here, and clear demo timer
     sta DemoTimer
     ldx #$17
-    lda #$00
 InitScores:
     sta ScoreAndCoinDisplay,x   ; clear player scores and coin displays
     dex
@@ -1227,8 +1222,6 @@ PrintVictoryMessages:
     bne IncMsgCounter        ; if set, branch to increment message counters
     lda PrimaryMsgCounter    ; otherwise load primary message counter
     beq ThankPlayer          ; if set to zero, branch to print first message
-    cmp #$09                 ; if at 9 or above, branch elsewhere (this comparison
-    bcs IncMsgCounter        ; is residual code, counter never reaches 9)
     ldy WorldNumber          ; check world number
     cpy #World8
     bne MRetainerMsg         ; if not at world 8, skip to next part
@@ -1292,7 +1285,6 @@ PlayerEndWorld:
     ldy WorldNumber           ; check world number
     cpy #World8               ; if on world 8, player is done with game,
     bcs EndChkBButton         ; thus branch to read controller
-    lda #$00
     sta AreaNumber            ; otherwise initialize area number used as offset
     sta LevelNumber           ; and level number control to start at area 1
     sta OperMode_Task         ; initialize secondary mode of operation
@@ -1623,9 +1615,6 @@ DisplayIntermediate:
     beq GameOverInter           ; if so, proceed to display game over screen
     lda AltEntranceControl      ; otherwise check for mode of alternate entry
     bne NoInter                 ; and branch if found
-    ldy AreaType                ; check if we are on castle level
-    cpy #$03                    ; and if so, branch (possibly residual)
-    beq PlayerInter
     lda DisableIntermediate     ; if this flag is set, skip intermediate lives display
     bne NoInter                 ; and jump to specific task, otherwise
 PlayerInter:
@@ -2138,8 +2127,6 @@ WriteBlankMT:
 
 ReplaceBlockMetatile:
     jsr WriteBlockMetatile    ; write metatile to vram buffer to replace block object
-    inc Block_ResidualCounter ; increment unused counter (residual code)
-    dec Block_RepFlag,x       ; decrement flag (residual code)
     rts                       ; leave
 
 DestroyBlockMetatile:
@@ -2615,12 +2602,9 @@ RepeatByte:
     lda #$00
     adc $01
     sta $01
-    lda #$3f                 ; sets vram address to $3f00
-    sta PPU_ADDRESS
     lda #$00
     sta PPU_ADDRESS
-    sta PPU_ADDRESS          ; then reinitializes it for some reason
+    sta PPU_ADDRESS          ; reinitialize vram address to $0000
-    sta PPU_ADDRESS
 UpdateScreen:
     ldx PPU_STATUS           ; reset flip-flop
     ldy #$00                 ; load first byte from indirect as a pointer
@@ -2906,8 +2890,6 @@ ISpr0Loop:
     sta Sprite_Data,y
     dey
     bpl ISpr0Loop
-    jsr DoNothing2           ; these jsrs doesn't do anything useful
-    jsr DoNothing1
     inc Sprite0HitDetectFlag ; set sprite #0 check flag
     inc OperMode_Task        ; increment to next task
     rts
@@ -3148,7 +3130,6 @@ TerminateGame:
     lda WorldNumber       ; otherwise put world number of current
     sta ContinueWorld     ; player into secret continue function variable
     lda #$00
-    asl                   ; residual ASL instruction
     sta OperMode_Task     ; reset all modes to title screen and
     sta ScreenTimer       ; leave
     sta OperMode
@@ -3194,15 +3175,6 @@ ExTrans:
 
 ;-------------------------------------------------------------------------------------
 
-DoNothing1:
-    lda #$ff  ; this is residual code, this value is
-    sta $06c9 ; not used anywhere in the program
-
-DoNothing2:
-    rts
-
-;-------------------------------------------------------------------------------------
-
 AreaParserTaskHandler:
     ldy AreaParserTaskNum     ; check number of tasks here
     bne DoAPTasks             ; if already set, go ahead
@@ -4007,7 +3979,6 @@ ExitCastle:
 
 WaterPipe:
     jsr GetLrgObjAttrib    ; get row and lower nybble
-    ldy AreaObjectLength,x ; get length (residual code, water pipe is 1 col thick)
     ldx $07                ; get row
     lda #$6b
     sta MetatileBuffer,x   ; draw something here and below it
@@ -4458,8 +4429,6 @@ DrawQBlk:
 
 GetAreaObjectID:
     lda $00  ; get value saved from area parser routine
-    sec
-    sbc #$00 ; possibly residual code
     tay      ; save to Y
 ExitDecBlock:
     rts
@@ -4514,7 +4483,6 @@ RenderUnderPart:
     beq WaitOneRow       ; if middle part (mushroom ledge), wait until next row
     cpy #$c0
     beq DrawThisRow      ; if question block w/ coin, overwrite
-    cpy #$c0
     bcs WaitOneRow       ; if any other metatile with palette 3, wait until next row
     cpy #$54
     bne DrawThisRow      ; if cracked rock terrain, overwrite
@@ -5698,8 +5666,6 @@ ScrollScreen:
     ora $00                    ; get saved bit here and save in PPU register 1
     sta Mirror_PPU_CTRL_REG1   ; mirror to be used to set name table later
     jsr GetScreenPosition      ; figure out where the right side is
-    lda #$08
-    sta ScrollIntervalTimer    ; set scroll timer (residual, not used elsewhere)
     jmp ChkPOffscr             ; skip this part
 InitScrlAmt:
     lda #$00
@@ -6120,7 +6086,7 @@ ExitDeath:
 FlagpoleSlide:
     lda Enemy_ID+5           ; check special use enemy slot
     cmp #FlagpoleFlagObject  ; for flagpole flag object
-    bne NoFPObj              ; if not found, branch to something residual
+    bne NoFPObj              ; if not found, branch to exit
     lda FlagpoleSoundQueue   ; load flagpole sound
     sta Square1SoundQueue    ; into square 1's sfx queue
     lda #$00
@@ -6132,8 +6098,8 @@ FlagpoleSlide:
 SlidePlayer:
     jmp AutoControlPlayer    ; jump to player control routine
 NoFPObj:
-    inc GameEngineSubroutine ; increment to next routine (this may
+    inc GameEngineSubroutine ; increment to next routine
-    rts                      ; be residual code)
+    rts
 
 ;-------------------------------------------------------------------------------------
 
@@ -6579,7 +6545,6 @@ SetAnimSpd:
 
 ImposeFriction:
     and Player_CollisionBits  ; perform AND between left/right controller bits and collision flag
-    cmp #$00                  ; then compare to zero (this instruction is redundant)
     bne JoypFrict             ; if any bits set, branch to next part
     lda Player_X_Speed
     beq SetAbsSpd             ; if player has no horizontal speed, branch ahead to last part
@@ -7299,7 +7264,6 @@ NoHammer:
 
 ;--------------------------------
 ; $00 - used to set downward force
-; $01 - used to set upward force (residual)
 ; $02 - used to set maximum speed
 
 ProcHammerObj:
@@ -7317,8 +7281,6 @@ ProcHammerObj:
     tax                        ; return offset to X
     lda #$10
     sta $00                    ; set downward movement force
-    lda #$0f
-    sta $01                    ; set upward movement force (not used)
     lda #$04
     sta $02                    ; set maximum vertical speed
     lda #$00                   ; set A to impose gravity on hammer
@@ -7414,7 +7376,6 @@ FMiscLoop:
     bne FMiscLoop          ; do this until all slots are checked
     ldy #$08               ; if no empty slots found, use last slot
 UseMiscS:
-    sty JumpCoinMiscOffset ; store offset of misc object buffer here (residual)
     rts
 
 ;-------------------------------------------------------------------------------------
@@ -7432,7 +7393,6 @@ MiscLoop:
 
 ;--------------------------------
 ; $00 - used to set downward force
-; $01 - used to set upward force (residual)
 ; $02 - used to set maximum speed
 
 ProcJumpCoin:
@@ -7462,8 +7422,6 @@ JCoinRun:
     sta $00
     lda #$06                 ; set maximum vertical speed
     sta $02
-    lsr                      ; divide by 2 and set
-    sta $01                  ; as upward movement amount (apparently residual)
     lda #$00                 ; set A to impose gravity on jumping coin
     jsr ImposeGravity        ; do sub to move coin vertically and impose gravity on it
     ldx ObjectOffset         ; get original misc object offset
@@ -7474,7 +7432,6 @@ JCoinRun:
 RunJCSubs:
     jsr RelativeMiscPosition ; get relative coordinates
     jsr GetMiscOffscreenBits ; get offscreen information
-    jsr GetMiscBoundBox      ; get bounding box coordinates (why?)
     jsr JCoinGfxHandler      ; draw the coin or floatey number
 
 MiscLoopBack:
@@ -7548,8 +7505,7 @@ SetupPowerUp:
     sec
     sbc #$08                 ; subtract 8 pixels
     sta Enemy_Y_Position+5   ; and use as vertical coordinate of power-up object
-PwrUpJmp:
+    lda #$01
-    lda #$01                 ; this is a residual jump point in enemy object jump table
     sta Enemy_State+5        ; set power-up object's state
     sta Enemy_Flag+5         ; set buffer flag
     lda #$03
@@ -7868,8 +7824,6 @@ SpawnBrickChunks:
     clc                       ; add 8 pixels to vertical coordinate
     adc #$08                  ; and save as vertical coordinate for one of them
     sta Block_Y_Position+2,x
-    lda #$fa
-    sta Block_Y_Speed,x       ; set vertical speed...again??? (redundant)
     rts
 
 ;-------------------------------------------------------------------------------------
@@ -8100,10 +8054,6 @@ SetXMoveAmt:
 MaxSpdBlockData:
     .byte $06, $08
 
-ResidualGravityCode:
-    ldy #$00         ; this part appears to be residual,
-    .byte $2c        ; no code branches or jumps to it...
-
 ImposeGravityBlock:
     ldy #$01              ; set offset for maximum speed
     lda #$50              ; set movement amount here
@@ -8124,13 +8074,8 @@ MovePlatformDown:
 MovePlatformUp:
     lda #$01       ; save value to stack
     pha
-    ldy Enemy_ID,x ; get enemy object identifier
     inx            ; increment offset for enemy object
     lda #$05       ; load default value here
-    cpy #$29       ; residual comparison, object #29 never executes
-    bne SetDplSpd  ; this code, thus unconditional branch here
-    lda #$09       ; residual code
-SetDplSpd:
     sta $00        ; save downward movement amount here
     lda #$0a       ; save upward movement amount here
     sta $01
@@ -8356,12 +8301,7 @@ CheckEndofBuffer:
     beq CheckRightBounds    ; if found, branch, otherwise
     cpx #$05                ; check for end of buffer
     bcc CheckRightBounds    ; if not at end of buffer, branch
-    iny
+    rts
-    lda (EnemyData),y       ; check for specific value here
-    and #%00111111          ; not sure what this was intended for, exactly
-    cmp #$2e                ; this part is quite possibly residual code
-    beq CheckRightBounds    ; but it has the effect of keeping enemies out of
-    rts                     ; the sixth slot
 
 CheckRightBounds:
     lda ScreenRight_X_Pos   ; add 48 to pixel coordinate of right boundary
@@ -8583,7 +8523,7 @@ InitEnemyRoutines:
     .addr PlatLiftUp
     .addr PlatLiftDown
     .addr InitBowser
-    .addr PwrUpJmp         ; possibly dummy value
+    .addr NoInitCode
     .addr Setup_Vine
 
     .addr NoInitCode         ; for objects $30-$36
@@ -10141,7 +10081,6 @@ NotDefB:
 
 SwimCCXMoveData:
     .byte $40, $80
-    .byte $04, $04 ; residual data, not used
 
 MoveSwimmingCheepCheep:
     lda Enemy_State,x         ; check cheep-cheep's enemy object state
@@ -10279,7 +10218,6 @@ SkpFSte:
 SetupGFB:
     sta $ef                     ; save high byte of spinning thing, modified or otherwise
     jsr RelativeEnemyPosition   ; get relative coordinates to screen
-    jsr GetFirebarPosition      ; do a sub here (residual, too early to be used now)
     ldy Enemy_SprDataOffset,x   ; get OAM data offset
     lda Enemy_Rel_YPos          ; get relative vertical coordinate
     sta Sprite_Y_Position,y     ; store as Y in OAM data
@@ -10494,9 +10432,6 @@ GetVAdder:
 PRandomSubtracter:
     .byte $f8, $a0, $70, $bd, $00
 
-FlyCCBPriority:
-    .byte $20, $20, $20, $00, $00
-
 MoveFlyingCheepCheep:
     lda Enemy_State,x         ; check cheep-cheep's enemy state
     and #%00100000            ; for d5 set
@@ -10535,9 +10470,7 @@ AddCCF:
     lsr
     tay
 BPGet:
-    lda FlyCCBPriority,y      ; load bg priority data and store (this is very likely
+    rts
-    sta Enemy_SprAttrib,x     ; broken or residual code, value is overwritten before
-    rts                       ; drawing it next frame), then leave
 
 ;--------------------------------
 ; $00 - used to hold horizontal difference
@@ -11002,20 +10935,14 @@ DrawFlameLoop:
     ldy Enemy_SprDataOffset,x  ; get OAM data offset
     lda Enemy_OffscreenBits    ; get enemy object offscreen bits
     lsr                        ; move d0 to carry and result to stack
-    pha
-    bcc M3FOfs                 ; branch if carry not set
-    lda #$f8                   ; otherwise move sprite offscreen, this part likely
-    sta Sprite_Y_Position+12,y ; residual since flame is only made of three sprites
-M3FOfs:
-    pla                        ; get bits from stack
     lsr                        ; move d1 to carry and move bits back to stack
     pha
     bcc M2FOfs                 ; branch if carry not set again
     lda #$f8                   ; otherwise move third sprite offscreen
     sta Sprite_Y_Position+8,y
 M2FOfs:
-    pla                        ; get bits from stack again
+    pla                        ; get bits from stack
-    lsr                        ; move d2 to carry and move bits back to stack again
+    lsr                        ; move d2 to carry and move bits back to stack
     pha
     bcc M1FOfs                 ; branch if carry not set yet again
     lda #$f8                   ; otherwise move second sprite offscreen
@@ -11267,7 +11194,6 @@ FirebarSpin:
     sta $07                     ; save spinning speed here
     lda FirebarSpinDirection,x  ; check spinning direction
     bne SpinCounterClockwise    ; if moving counter-clockwise, branch to other part
-    ldy #$18                    ; possibly residual ldy
     lda FirebarSpinState_Low,x
     clc                         ; add spinning speed to what would normally be
     adc $07                     ; the horizontal speed
@@ -11277,7 +11203,6 @@ FirebarSpin:
     rts
 
 SpinCounterClockwise:
-    ldy #$08                    ; possibly residual ldy
     lda FirebarSpinState_Low,x
     sec                         ; subtract spinning speed to what would normally be
     sbc $07                     ; the horizontal speed
@@ -11604,11 +11529,9 @@ ExDPl:
     rts                         ; leave
 
 ;--------------------------------
-; $00 - residual value from sub
 
 RightPlatform:
     jsr MoveEnemyHorizontally   ; move platform with current horizontal speed, if any
-    sta $00                     ; store saved value here (residual code)
     lda PlatformCollisionFlag,x ; check collision flag, if no collision between player
     bmi ExRPl                   ; and platform, branch ahead, leave speed unaltered
     lda #$10
@@ -11938,9 +11861,6 @@ NoPUp:
 
 ;--------------------------------
 
-ResidualXSpdData:
-    .byte $18, $e8
-
 KickedShellXSpdData:
     .byte $30, $d0
 
@@ -13243,7 +13163,6 @@ ChkLandedEnemyState:
     beq ProcEnemyDirection   ; then branch elsewhere
     cmp #$03                 ; if already in state used by koopas and buzzy beetles
     bcs ExSteChk             ; or in higher numbered state, branch to leave
-    lda Enemy_State,x        ; load enemy state again (why?)
     cmp #$02                 ; if not in $02 state (used by koopas and buzzy beetles)
     bne ProcEnemyDirection   ; then branch elsewhere
     lda #$10                 ; load default timer here
@@ -13750,21 +13669,12 @@ BlockBufferChk_Enemy:
     pla               ; pull A from stack and jump elsewhere
     jmp BBChk_E
 
-ResidualMiscObjectCode:
-    txa
-    clc                 ; supposedly used once to set offset for
-    adc #$0d            ; miscellaneous objects
-    tax
-    ldy #$1b            ; supposedly used once to set offset for block buffer data
-    jmp ResJmpM         ; probably used in early stages to do misc to bg collision detection
-
 BlockBufferChk_FBall:
     ldy #$1a                 ; set offset for block buffer adder data
     txa
     clc
     adc #$07                 ; add seven bytes to use
     tax
-ResJmpM:
     lda #$00                 ; set A to return vertical coordinate
 BBChk_E:
     jsr BlockBufferCollision ; do collision detection subroutine for sprite object
@@ -13999,7 +13909,7 @@ NoHOffscr:
 ;-------------------------------------------------------------------------------------
 ; $00-$01 - used to hold tile numbers ($01 addressed in draw floatey number part)
 ; $02 - used to hold Y coordinate for floatey number
-; $03 - residual byte used for flip (but value set here affects nothing)
+; $03 - used for flip
 ; $04 - attribute byte for floatey number
 ; $05 - used as X coordinate for floatey number
 
@@ -14028,7 +13938,7 @@ FlagpoleGfxHandler:
     lda FlagpoleFNum_Y_Pos        ; get vertical coordinate for floatey number
     sta $02                       ; store it here
     lda #$01
-    sta $03                       ; set value for flip which will not be used, and
+    sta $03                       ; set value for flip, and
     sta $04                       ; attribute byte for floatey number
     sta Sprite_Attributes,y       ; set attribute bytes for all three sprites
     sta Sprite_Attributes+4,y
@@ -14612,7 +14522,6 @@ CheckToAnimateEnemy:
     ldy #$00
     cmp #$15                ; check for mushroom retainer/princess object
     bne CheckForSecondFrame ; which uses different code here, branch if not found
-    iny                     ; residual instruction
     lda WorldNumber         ; are we on world 8?
     cmp #World8
     bcs CheckDefeatedState  ; if so, leave the offset alone (use princess)
@@ -16189,9 +16098,6 @@ PowerUpGrabFreqData:
     .byte $28, $4a, $50, $4a, $64, $3c, $32, $3c, $32
     .byte $2c, $24, $3a, $64, $3a, $34, $2c, $22, $2c
 
-; residual frequency data
-    .byte $22, $1c, $14
-
 PUp_VGrow_FreqData:
     .byte $14, $04, $22, $24, $16, $04, $24, $26 ; used by both
     .byte $18, $04, $26, $28, $1a, $04, $28, $2a
@@ -16508,8 +16414,7 @@ HandleAreaMusicLoopB:
     bne GMLoopB              ; unconditional branch
 
 FindAreaMusicHeader:
-    ldy #$08                ; load Y for offset of area music
+    ldy #$08         ; load Y for offset of area music
-    sty MusicOffset_Square2 ; residual instruction here
 
 FindEventMusicHeader:
     iny                      ; increment Y pointer based on previously loaded queue contents
@@ -16875,9 +16780,6 @@ Star_CloudHdr:
 EndOfLevelMusHdr:
     .byte $20, <WinLevelMusData, >WinLevelMusData, $3c, $21
 
-ResidualHeaderData:
-    .byte $20, $c4, $fc, $3f, $1d
-
 UndergroundMusHdr:
     .byte $18, <UndergroundMusData, >UndergroundMusData, $00, $00