Difference between revisions of "Shippu Mahou Daisakusen/Reverse engineering notes"

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m
(Moved tables of values to the Racing subpage, just leaving the RE details here)
 
(One intermediate revision by the same user not shown)
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* 100553 - current play flags?
 
* 100553 - current play flags?
 
* 100555 - current P1 lives
 
* 100555 - current P1 lives
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 +
* 10055c - current P1 character
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10055c character values:
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{| class="wikitable"
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|-
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! Gain !! Chitta !! Miyamoto !! Bornnam !! Nirvana !! Kickle & Laycle !! Honest John !! Bul-Gin
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|-
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| 0|| 1 || 2 || 3 || 4 || 5 || 6 || 7
 +
|}
  
 
* 10058C = current calculated rank
 
* 10058C = current calculated rank
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* 1006A4 = survival rank increment timer (does not reset on stage start)
 
* 1006A4 = survival rank increment timer (does not reset on stage start)
  
* 102C4A + $44 (102C8E) = base scroll speed?
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* 102C4A + $44 (102C8E) = maximum unboosted speed  
* 102C4A + $46 (102C90) =  
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* 102C4A + $46 (102C90) = minimum unboosted speed
* 102C4A + $22 (102c6c) = speedometer?
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* 102C4A + $22 (102C6C) = current speed
  
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* 1012DE = P1 main shot power
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* 1012D6 = P1 bomb count
 
* 1012DA = P1 sub-weapon type
 
* 1012DA = P1 sub-weapon type
 
* 1012D8 = P1 sub-weapon power
 
* 1012D8 = P1 sub-weapon power
Line 36: Line 48:
 
* 100656 - table of P1 track times
 
* 100656 - table of P1 track times
 
* 10066E - table of track selections
 
* 10066E - table of track selections
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== Speed and Boost Mechanics ==
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 +
This section describes how the details in [[Shippu_Mahou_Daisakusen/Racing#Technical_details]] were found.
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 +
Minimum and maximum speed values for each track can be confirmed by watching the addresses 102C8E (max) and 102C90 (min) while playing through the game.
 +
 +
For boost mechanics, the relevant routines are at 7AD6 and 174D0. The routine at 7AD6 reads from a table stored at 718C2, which contains the base boost speed values for each character and stage. The routine at 174D0 applies the main shot power bonus and the bomb count modifier, using tables stored at 17568 (shot power bonus) and 175AE (bomb count modifier).
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Note: Routine 174D0 also seems to do some stuff related to subweapons (probably damage calculations?) and there's a big table of subweapon-related values at 1756E.

Latest revision as of 14:18, 3 April 2026

TODO: clean up addresses below pointing directly to bytes when code is operating on them as words. e.g., P1 lives @ 100555.b is probably referenced in the code as 100554.w

  • 1006C6 - seems to consistently hold boss HP value when one is on screen
  • 1006AA - base address of the boss enemy object
  • object+$04 - animation frame
  • object+$06 - animation related flags (sprite rotation, hit flash and/or palette?, etc.)
  • object+$08 - y-coord
  • object+$0A - x-coord
  • object+$1C - HP value for enemies. Damage value for projectiles/player, to apply against target enemy up to their specified durability cap
  • object+$36 - i-frames
  • Code @ 13D78 - damage calculation for durable enemies
  • Code @ 13F6A - damage calculation for zakos (uncapped)
  • 100551 - current play state?
  • 100553 - current play flags?
  • 100555 - current P1 lives
  • 10055c - current P1 character

10055c character values:

Gain Chitta Miyamoto Bornnam Nirvana Kickle & Laycle Honest John Bul-Gin
0 1 2 3 4 5 6 7
  • 10058C = current calculated rank
  • 10058E = base rank for current stage
  • 100590 = survival rank (resets on stage start or player death)
  • 1006A4 = survival rank increment timer (does not reset on stage start)
  • 102C4A + $44 (102C8E) = maximum unboosted speed
  • 102C4A + $46 (102C90) = minimum unboosted speed
  • 102C4A + $22 (102C6C) = current speed
  • 1012DE = P1 main shot power
  • 1012D6 = P1 bomb count
  • 1012DA = P1 sub-weapon type
  • 1012D8 = P1 sub-weapon power
  • 1005B1 - current stage
  • 1005B3 - current track
  • 1005B5 - current loop (0 = first, 1 = second)
  • 100656 - table of P1 track times
  • 10066E - table of track selections

Speed and Boost Mechanics

This section describes how the details in Shippu_Mahou_Daisakusen/Racing#Technical_details were found.

Minimum and maximum speed values for each track can be confirmed by watching the addresses 102C8E (max) and 102C90 (min) while playing through the game.

For boost mechanics, the relevant routines are at 7AD6 and 174D0. The routine at 7AD6 reads from a table stored at 718C2, which contains the base boost speed values for each character and stage. The routine at 174D0 applies the main shot power bonus and the bomb count modifier, using tables stored at 17568 (shot power bonus) and 175AE (bomb count modifier).

Note: Routine 174D0 also seems to do some stuff related to subweapons (probably damage calculations?) and there's a big table of subweapon-related values at 1756E.