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As noted in 📝 P0061, TH03 gameplay RE is indeed going to progress very slowly in the beginning. A lot of the initial progress won't even be reflected in the RE% – there are just so many features in this game that are intertwined into each other, and I only consider functions to be "reverse-engineered" once we understand every involved piece of code and data, and labeled every absolute memory reference in it. (Yes, that means that the percentages on the front page are actually underselling ReC98's progress quite a bit, and reflect a pretty low bound of our actual understanding of the games.)

So, when I get asked to look directly at gameplay code right now, it's quite the struggle to find a place that can be covered within a push or two and that would immediately benefit scoreplayers. The basics of score and combo handling themselves managed to fit in pretty well, though:

  • Just like TH04 and TH05, TH03 stores the current score as 8 binary-coded decimal digits. Since the last constant 0 is not included, the maximum score displayable without glitches therefore is 999,999,990 points, but the game will happily store up to 24,699,999,990 points before the score wraps back to 0.
  • There are (surprisingly?) only 6 places where the game actually adds points to the score. Not quite sure about all of them yet, but they (of course) include ending a combo, killing enemies, and the bonus at the end of a round.
  • Combos can be continued for 80 frames after a 2-hit. The hit counter can only be increased in the first 48, and effectively resets to 0 for the last 32, when the Spell Point value starts blinking.
  • TH03 can track a total of 16 independent "hit combo sources" per player, simultaneously. These are not related to the number of actual explosions; rather, each explosion is assigned to one of the 16 slots when it spawns, and all consecutive explosions spawned from that one will then add to the hit combo in that slot. The hit number displayed in the top left is simply the largest one among all these.

Oh well, at least we still got a bit of PI% out of this one. From this point though, the next push (or two) should be enough to cover the big 128-byte player structure – which by itself might not be immediately interesting to scoreplayers, but surely is quite a blocker for everything else.