Daily SMB HL Disassembly Post #7

Presented with no comment for now:

001 JumpMForceData: 002 .byte $20, $20, $1e, $28, $28, $0d, $04 003 004 FallMForceData: 005 .byte $70, $70, $60, $90, $90, $0a, $09 006 007 PlayerYSpdData: 008 .byte $fc, $fc, $fc, $fb, $fb, $fe, $ff 009 010 InitMForceData: 011 .byte $00, $00, $00, $00, $00, $80, $00 012 013 MaxLeftXSpdData: 014 .byte $d8, $e8, $f0 015 016 MaxRightXSpdData: 017 .byte $28, $18, $10 018 .byte $0c ; used for pipe intros 019 020 FrictionData: 021 .byte $e4, $98, $d0 022 023 Climb_Y_SpeedData: 024 .byte $00, $ff, $01 025 026 Climb_Y_MForceData: 027 .byte $00, $20, $ff ; -1 028 029 .code 030 031 .proc PlayerPhysicsSub 032 033 FrictionOffset = temp_byte ; - used to store offset to friction data ( address $00) 034 035 if Player_State = #3 ; check player state, if climbing: 036 037 ldy #0 038 ; get controller bits for up/down; check against player's collision detection bits, if pressing up/down: 039 if a := Up_Down_Buttons & Player_CollisionBits 040 iny 041 if ! a & #BUTTON_UP ; check for pressing up only 042 iny 043 endif 044 endif 045 046 mb x, Player_Y_MoveForce := Climb_Y_MForceData[ Y ] ; store as vertical movement force 047 048 lda #$08 ; load default animation timing 049 mb x, Player_Y_Speed := Climb_Y_SpeedData[ y ] ; store as vertical speed 050 051 if positive ; if climbing down, use default animation timing value 052 lsr ; otherwise divide timer setting by 2 053 endif 054 055 sta PlayerAnimTimerSet ; store animation timer setting and leave 056 rts 057 058 endif ; else: not climbing: 059 060 ;------------------------------------------------------------------------------------------------ 061 062 ; OP -> note two 'jmp X_Physics' a few branches apart 063 064 065 ; if JumpspringAnimCtrl set OR 'A' not pressed OR Previously 'A' was pressed 066 if JumpspringAnimCtrl || ! A_B_Buttons & #BUTTON_A || a & PreviousA_B_Buttons 067 NoJump: 068 jmp X_Physics 069 endif 070 071 ; if here, There is no jumpspring and a there is a valid A button press: 072 073 if lda Player_State ; check player state, not zero = not on ground 074 075 if !SwimmingFlag goto NoJump ; if swimming flag not set (comment this line for air jumping) 076 ; if here, we are swimming: 077 ; if jump/swim timer zero AND player's vertical speed UP 078 if !JumpSwimTimer && Player_Y_Speed == negative 079 jmp X_Physics ; if timer at zero and player still rising, do not swim 080 endif 081 endif 082 083 ; Do Y Physics (Jumping or Swimming): 084 085 mb JumpSwimTimer := #$20 ; set jump/swim timer 086 mb y := #0 087 mb Player_YMF_Dummy := y ; #0 088 mb Player_Y_MoveForce := y ; #0 089 mb JumpOrigin_Y_HighPos := Player_Y_HighPos 090 mb JumpOrigin_Y_Position := Player_Y_Position 091 mb Player_State := #1 ; set player state to jumping/swimming 092 093 lda Player_XSpeedAbsolute 094 ; check value related to walking/running speed 095 if a < #$09 goto CheckSwimming 096 iny ; 1 097 if a < #$10 goto CheckSwimming 098 iny ; 2 099 if a < #$19 goto CheckSwimming 100 iny ; 3 101 if a < #$1c goto CheckSwimming 102 iny ; 4 103 104 CheckSwimming: 105 106 mb DiffToHaltJump := #1 107 108 if SwimmingFlag 109 ldy #5 110 if Whirlpool_Flag 111 iny ; 6 112 endif 113 endif 114 115 ; store appropriate jump/swim 116 117 mb VerticalForce := JumpMForceData[ y ] ; data here 118 mb VerticalForceDown := FallMForceData[ y ] 119 mb Player_Y_MoveForce := InitMForceData[ y ] 120 mb Player_Y_Speed := PlayerYSpdData[ y ] 121 122 if SwimmingFlag ; if swimming 123 mb Square1SoundQueue := #SFX_EnemyStomp ; load swim/goomba stomp sound 124 if Player_Y_Position >= #$14 goto X_Physics ; if below a certain point, branch 125 mb Player_Y_Speed := #0 ; otherwise reset player's vertical speed to stay below water 126 else ; not swimming: 127 lda #SFX_BigJump ; load big mario's jump sound by default 128 if ldy PlayerSize == SmallMario ; if mario is small 129 lda #SFX_SmallJump ; load small mario's jump sound 130 endif 131 sta Square1SoundQueue ; store appropriate jump sound in square 1 sfx queue 132 endif 133 134 ; --------------------------------------------------------------------------------- 135 136 X_Physics: 137 138 mb y, FrictionOffset := #0 ; init value here 139 140 if Player_State != zero ; if mario is not on the ground 141 if Player_XSpeedAbsolute >= #$19 goto GetXPhy ; check something that seems to be related to mario's speed 142 else C clear ; mario on ground: 143 iny 144 if lda AreaType != zero ; check area type, if not water: 145 dey ; decrement Y by default for non-water type area 146 if Left_Right_Buttons = Player_MovingDir ; get left/right controller bits, check against moving direction 147 if A_B_Buttons & #BUTTON_B goto SetRunningTimer ; check for b button pressed if pressed, skip ahead to set timer 148 if RunningTimer goto GetXPhy ; check for running timer set 149 endif 150 endif 151 endif 152 153 iny ; if running timer not set or level type is water, 154 inc FrictionOffset ; increment Y again and temp variable in memory 155 156 if RunningSpeed || Player_XSpeedAbsolute >= #$21 ; if running speed set or speed => $21 increment FrictionOffset 157 158 inc FrictionOffset 159 160 ; endif could go here for better code, but waste of cycles.. 161 162 jmp GetXPhy ; and jump ahead 163 164 SetRunningTimer: 165 mb RunningTimer := #$0a ; if b button pressed and pressing direction of movment, set running timer 166 167 endif 168 GetXPhy: 169 170 171 mb MaximumLeftSpeed := MaxLeftXSpdData[ y ] ; get maximum speed to the left 172 173 if GameEngineSubroutine = #$07 ; check for specific routine running 174 ldy #3 175 endif 176 177 mb MaximumRightSpeed := MaxRightXSpdData[ y ] ; get maximum speed to the right 178 ldy FrictionOffset ; get other value in memory 179 mb FrictionAdderLow := FrictionData[ y ] ; get value using value in memory as offset 180 mb FrictionAdderHigh := #0 ; init something here 181 182 if PlayerFacingDir <> Player_MovingDir ; check facing direction against moving direction 183 asl FrictionAdderLow ; otherwise shift d7 of friction adder low into carry 184 rol FrictionAdderHigh ; then rotate carry onto d0 of friction adder high 185 endif 186 187 rts ; and then leave 188 189 .endproc

Ca65hl Macros

If you are interested in using the ca65 macros that are used on this blog, I'm going to keep them updated here: https://www.assembla.com/code/ca65hl/git/nodes There is also a nice wiki on assembla that I plan on updating. There is not much there at this time, but there will be more soon.

Daily SMB HL Disassembly Post #6

I've arbitrary selected this code to post next.
This code is run to display the points won when jumping onto an enemy, hitting a coinblock or grabbing a mushroom, etc.
There is a scetion where it checks if the current enemy falls within a certain range of tests and uses a different OAM offset, but I am uncertian what the purpose is. Otherwise, this is pretty easy to follow.

FloateyNum[ x ]::Control - the score to award (or a 1up)
FloateyNum[ x ]::X_Pos - the screen x pos
FloateyNum[ x ]::Y_Pos - the screen y pos

Note the FloateyNum is not initailized here, just processed, The Spawning code will be posted soon.

001 ; DATA 002 ; Sprite tile pairs: 003 004 FloateyNumTileData: 005 006 .byte $ff, $ff ; dummy 007 .byte $f6, $fb ; "100" 008 .byte $f7, $fb ; "200" 009 .byte $f8, $fb ; "400" 010 .byte $f9, $fb ; "500" 011 .byte $fa, $fb ; "800" 012 .byte $f6, $50 ; "1000" 013 .byte $f7, $50 ; "2000" 014 .byte $f8, $50 ; "4000" 015 .byte $f9, $50 ; "5000" 016 .byte $fa, $50 ; "8000" 017 .byte $fd, $fe ; "1-UP" 018 019 ScoreUpdateData: 020 021 ; high nybble is digit number ( 4 is 100, 3 is 1000), low nybble is number to 022 ; add to the digit of the player's score 023 024 .byte $ff ; dummy 025 .byte $41, $42, $44, $45, $48 026 .byte $31, $32, $34, $35, $38 027 .byte $00 ; 1 up 028 029 .code 030 031 ;---------------------------------------------------------------------------------------------- 032 033 .proc FloateyNumbersRoutine 034 035 ; load control for floatey number, if zero, branch to leave 036 if lda FloateyNum[ x ]::Control == zero goto PlayerEndWorld::Exit 037 038 if a >= #$0b 039 mb FloateyNum[ x ]::Control := #$0b ; set to $0b, thus keeping it in range 040 endif 041 042 tay ; use as Y 043 044 if !FloateyNum_Timer[ x ] ; check value here 045 mb FloateyNum[ x ]::Control := a ; #0 ; initialize floatey number control and leave 046 rts 047 endif 048 049 dec FloateyNum_Timer,x ; decrement value here 050 051 ; if FloateyNum_Timer = 2b (before decrement) 052 if a = #$2b 053 054 ; if FloateyNum[ x ]::Control = #$0b 055 if y = #$0b ; check offset for $0b 056 inc NumberofLives ; give player one extra life (1-up) 057 mb Square2SoundQueue := #Sfx_ExtraLife ; and play the 1-up sound 058 endif 059 060 ; use as X offset, essentially the digit to be incremented 061 mb x := ScoreUpdateData[ y ] >> 4 062 ; mask out the high nybble, store as amount to add to the digit 063 mb DigitModifier[ x ] := ScoreUpdateData[ y ] & #%00001111 064 065 jsr AddToScore ; update the score accordingly 066 067 endif 068 069 ldy Enemy_SprDataOffset,x ; get OAM data offset for enemy object 070 071 072 ; This section of codes purpose is uncertain: 073 ; ------------------------------------------------ 074 mb a := Enemy_ID[ x ] 075 ; if enemy is not spiny AND not Pplant AND ( is hammerbro OR 076 ; ( Not either cheepcheep AND ( greater or equal to tallenemy OR state less than #2)) ) 077 078 if a <> #Spiny && a <> #PiranhaPlant && ( a = #HammerBro || \ 079 ( a <> #GreyCheepCheep && a <> #RedCheepCheep && ( a >= #TallEnemy || Enemy_State[x] < #$02 ) ) ) 080 ldx SprDataOffset_Ctrl ; load some kind of control bit 081 ldy Alt_SprDataOffset,x ; get alternate OAM data offset 082 ldx ObjectOffset ; get enemy object offset again 083 endif 084 ; ------------------------------------------------ 085 086 087 if FloateyNum[ x ]::Y_Pos >= #$18 ; if coordinate is below the status bar: 088 ; carry is clear 089 mb FloateyNum[ x ]::Y_Pos := a -- #1 ; subtract one (move up one pixel) and store as new 090 endif 091 092 mb a := FloateyNum[ x ]::Y_Pos -- #8 ; subtract eight and dump into the 093 jsr DumpTwoSpr ; left and right sprite's Y coordinates 094 095 mb Sprite[ y ]::X_Position := FloateyNum[ x ]::X_Pos ; X coordinate of left sprite 096 mb Sprite[ y + 4 ]::X_Position := a + #8 ; X coordinate of right sprite 097 098 mb a := #$02 099 mb Sprite[ y ]::Attributes := a ; set palette control in attribute bytes 100 mb Sprite[ y + 4 ]::Attributes := a ; of left and right sprites 101 102 mb x := FloateyNum[ x ]::Control * 2 ; and use as offset for look-up table 103 mb Sprite[ y ]::Tilenumber := FloateyNumTileData[ x ] ; display first half of number of points 104 mb Sprite[ y + 4 ]::Tilenumber := FloateyNumTileData[ x + 1 ] ; display the second half 105 106 ldx ObjectOffset ; get enemy object offset and leave 107 rts 108 109 .endproc