DoukutsuNikki/PHILOSOPHY.md

accurate branch

Being a pure, plain decompilation of the original Doukutsu.exe file (v1.0.0.6), there should not be much to say about this branch's philosophies:

Goal

The end-goal is for the project to be able to produce an .exe file that is identical to the original. This means that there should be no custom code, decompiled code should ideally be made to produce the same assembly code as the original, bugs should be left intact, etc.

Another goal of the project is to document Cave Story's inner-working, so code should be reasonably-annotated. Likewise, bugs should be documented, and fixes provided wrapped in #ifdef FIX_BUGS conditions.

Accuracy to the original source code

Personally, I do aim to make the decompiled code functionally-accurate to the original, down to generating the same assembly code, but I do not aim for visually-accurate code.

Despite this, I do try to preserve the original function/variable names, variable-declaration locations, and source file naming.

Part of the reason why I do not aim for visually-accurate source code is that we know from the Organya source code release what Pixel's code-style looked like, and I find it extremely hard to read.

Language

Cave Story's developer, Pixel, primarily speaks Japanese, but his code's variable/function names are mostly written in English (with a few rare instances of Romanised Japanese).

The Organya source code release indicates Pixel wrote his comments in Japanese, however, in this project, I prefer them to be written in English.

The English employed in this project is a mix of American English, Canadian English, and British English.

portable branch

This branch takes a different direction to the accurate branch, but they still share some core philosophies:

Goal

The goal is still to accurately-reproduce Cave Story's original code, but modified to the extent that it is easy to port to other platforms. This branch is intended for purists that don't want to use Windows or its deprecated APIs.

Notably, this means bugs should still be left intact. However, bugs and other coding errors that affect portability should be fixed.

For comparison, I believe this branch shares some parallels with the Chocolate Doom project, except perhaps more strict. See the link below for their list of philosophies which may be applicable here:

https://github.com/chocolate-doom/chocolate-doom/blob/master/PHILOSOPHY.md

Custom code

Cave Story's original source code was written in C++, but stylised like C89 (with a number of exceptions). Custom code added to the project should follow suit, but the C-style doesn't have to be C89 - personally, I prefer to write in the subset of C99 that C++98 allows.

I prefer compiler-specific code to be avoided, since more-portable code benefits all compilers, and keeps the codebase free of clutter.

enhanced-lite branch

This branch deviates the most from the accurate branch, focussing less on authenticity, and more on improving the base engine.

Goal

This branch is intended to benefit modders, by providing a feature-rich base for mods, while still keeping the original game's 'feel' (think of the Boom project rather than Chocolate Doom or GZDoom).

That said, I want to avoid the codebase becoming an over-engineered mess of seldom-used and niche features - only features with a strong reason to be included should be added.

Priority features include ones that already exist in the modding community as "EXE hacks", such as...

• Common custom TSC commands ('<MIM', '<PHY')
• Custom weapons
• A money system
• The "Cave Story Mod Loader" (widescreen, support for Ogg Vorbis music)

Note that such features should only be added if they see widespread use.

Target audience

While this branch is meant as a base for mods, it is not intended for modders unfamiliar with programming. This means features that only exist to benefit non-programmers will not be accepted, as they will likely clutter the codebase, making it harder for programmers to make modifications.

Accuracy to the original source code

Despite this branch being less accuracy-focussed, I still want modifications to the vanilla code to be minimal - that means no rewriting code to "look nicer" or add micro-optimisations.

Keeping the vanilla code intact guarantees CSE2E will accurately-reproduce Cave Story's gameplay, avoiding an NXEngine-scenario where the game is riddled with inaccuracies, both small and large. This also has the benefit of making it easier to merge changes from the other branches.

Enhancements unrelated to modding

Some features have made their way into this branch, despite not actually being of any direct use to modders - one example of this is the option to disable the pixel-alignment effect.

The reason for allowing these features is that, while they are of no direct benefit to modders, they are of benefit to players. Thus, a mod with these features is better than a mod without them. Likewise, the input-rebinding menu falls under a similar use.

The line is drawn when a feature comes at a detriment to modders - for example, having an option to select an alternative soundtrack (such as the Nicalis ones) is nice for the player, but will complicate modding, as, if a mod includes custom music, the modder will either have to disable the soundtracks they don't support, or they'll have to create multiple versions of each song.

enhanced branch

This branch is built upon the enhanced-lite branch, and follows similar ideals to said branch. However, this branch targets players rather than modders, allowing a greater range of features to be added.