The translation units were probably a better place back when most of
the codebase was still compiled in C mode, we only had a few C++ TUs,
almost everything needed to be declared as `extern "C"`, and moving
these declarations into the headers would have been really noisy with
all the `#ifdef __cplusplus` / `#endif` required. Nowadays though,
we've greatly reduced that surface area. And given that headers will
include even more headers as part of the upcoming `#include` cleanup,
it makes sense to make the jump now.
Part of P0284, funded by [Anonymous] and Blue Bolt.
The vertical shmup counterpart to 841d8be. Cleans up the subsystem
hierarchy by ensuring that at least all tile /formats/ code does not
depend on /main/ code.
Part of P0258, funded by [Anonymous] and Blue Bolt.
By now, it has become clear that this the norm rather than the
exception among these units. Thankfully!
Part of P0245, funded by [Anonymous], Blue Bolt, Ember2528, and Yanga.
The .PTN functions, vector functions, and egc_copy_rect_1_to_0_1()
(finally!) from TH01, as well as playfld.hpp from all games(finally!),
together with a bunch of other functions in their vicinity.
Part of P0201, funded by Ember2528 and Yanga.
nmlgc