* Previously used to determine whether to apply a horizon adjustment on whether local variable `horiz` was 0 or not (since baseline horizon was 100).
* For no particular reason, initalise `horiz` as FRACUNIT and process if it is not equal to one.
* Struct made up of binangle class units.
* Create signed clone of binangle for use with look_ang and rotscrnang.
* Append currently outgoing function names with `2` at the end to avoid conflict.
* Started with the most complicated game first.
* Struct made up of fixedhoriz class units.
* Append currently outgoing function names with `2` at the end to avoid conflict.
* Blood had this right. It makes sense that the horizon be based around as it's easier to work with.
* Removed all associated game math to deduct default horizon of 100 when doing weapon zvel etc, meaning actual horizon can just be used.
* Re-did return to center function to work on the already converted pitch. Return speed should be 1:1 with previous code.
* Duke/RR: Fix `SB_CENTERVIEW` not clearing while `cl_syncinput 1`.
* Duke/RR: Remove superfluous call to `apply_seasick()`.
* RR: Change two calls from `playerSetAngle()` to `playerAddAngle()` Updated version of `playerSetAngle()` doesn't stop setting angle until target is reached, a bit too strict for this and compromised vehicle turning.
* `applylook()`: Remove dead flag. Was only used with Duke, no other game called the function when dead anyway. Since the input helpers are processed outside of `applylook()` now this is not needed.
* `applylook()`: Extend function with a bit of commentary.
* For Blood/SW, exposes `SB_LOOK_LEFT`/`SB_LOOK_RIGHT` to games, hooking up `q16look_ang` and `q16rotscrnang` within.
* For SW, use Duke & Blood's return to center function and remove `PF_TURN_180` bit.
* For RR, replace a few misused bits with some bools inside of `player_struct`.
* Since bulk of functionality is sourced from Duke (30Hz), apply proper scaling so SW speed matches (40Hz).
* For Duke/SW, we continually apply `SB_CENTERVIEW` only if it was previously a toggled action, similar to Blood.
* For SW, we remove two SW-specific bits (`PF_LOCK_HORIZ` and `PF_LOOKING`) that are no longer needed.
* For Duke, we remove `return_to_center` and just use the `SB_CENTERVIEW` action bit as required.
* For `sethorizon()`, feature set and adjustment speeds are an averaged out accumulation across Duke/SW:
** GameTicRate is factored in for adjustment decisions to provide consistency for SW being the faster game.
** Adjustment amounts are half way between Duke/SW.
They created different code depending on the passed index, this was changed to always emit the optional parameter, even when not needed, so that the interpreter does not need to second-guess.
This timer only gets incremented by the main game ticker when the playsim is running.
This timer gets used for all playsim-related timing and animations so that these are decoupled from imprecisions in the global timer.
* Build timer still requires initialisation due to multiple `timerSetCallback()` that still need to work.
# Conflicts:
# source/core/menu/menu.cpp
# source/games/duke/src/game.cpp
