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Showing all posts tagged midboss-

📝 Posted:
🚚 Summary of:
P0029, P0030
Commits:
6ff427a...c7fc4ca, c7fc4ca...dea40ad
💰 Funded by:
zorg
🏷 Tags:
rec98+ th02+ th04+ th05+ blitting+ gameplay+ midboss- boss+ tcc+

Here we go, new C code! …eh, it will still take a bit to really get decompilation going at the speeds I was hoping for. Especially with the sheer amount of stuff that is set in the first few significant functions we actually can decompile, which now all has to be correctly declared in the C world. Turns out I spent the last 2 years screwing up the case of exported functions, and even some of their names, so that it didn't actually reflect their calling convention… yup. That's just the stuff you tend to forget while it doesn't matter.

To make up for that, I decided to research whether we can make use of some C++ features to improve code readability after all. Previously, it seemed that TH01 was the only game that included any C++ code, whereas TH02 and later seemed to be 100% C and ASM. However, during the development of the soon to be released new build system, I noticed that even this old compiler from the mid-90's, infamous for prioritizing compile speeds over all but the most trivial optimizations, was capable of quite surprising levels of automatic inlining with class methods…

…leading the research to culminate in the mindblow that is 9d121c7 – yes, we can use C++ class methods and operator overloading to make the code more readable, while still generating the same code than if we had just used C and preprocessor macros.

Looks like there's now the potential for a few pull requests from outside devs that apply C++ features to improve the legibility of previously decompiled and terribly macro-ridden code. So, if anyone wants to help without spending money…

📝 Posted:
🚚 Summary of:
P0028
Commits:
6023f5c...6ff427a
💰 Funded by:
zorg
🏷 Tags:
rec98+ th04+ th05+ gameplay+ midboss- boss+

Back to actual development! Starting off this stretch with something fairly mechanical, the few remaining generic boss and midboss state variables. And once we start converting the constant numbers used for and around those variables into decimal, the estimated position independence probability immediately jumped by 5.31% for TH04's MAIN.EXE, and 4.49% for TH05's – despite not having made the game any more position- independent than it was before. Yup… lots of false positives in there, but who can really know for sure without having put in the work.

But now, we've RE'd enough to finally decompile something again next, 4 years after the last decompilation of anything!

📝 Posted:
🚚 Summary of:
P0041
Commits:
b03bc91...f3b6137
💰 Funded by:
-Tom-
🏷 Tags:
rec98+ th04+ th05+ gameplay+ midboss- boss+

So, after introducing instruction number statistics… let's go for over 2,000 lines that won't show up there immediately :tannedcirno: That being (mid-)boss HP, position, and sprite ID variables for TH04/TH05. Doesn't sound like much, but it kind of is if you insist on decimal numbers for easier comparison with uth05win's source code.