* DObjects may not be memset to 0.
* There was still code trying to retrieve the player index with pointer artithmetic. With an array of pointers this does not work.
* Something strange was going on here with Blood where the static_cast would not work... Moved the player structure into `bloodactor.h` for now to work around it.
* Reverts 272dfa762d, but is a fresh implementation.
* I doubted anyone was doing this but apparently not.
* Exhumed needed a bit more work as it has very specific underwater checks.
* Was done in 67c7dd65f9 but caused issues.
* Reverted in 3d6f1e1a04 to ensure the game worked as expected.
* Actual problem identified and isolated to remove this duplication.
* `cl_viewbob` extended from bool to int, and allowing two modes: 1 == Powerslave Exhumed bobbing, 2 == Duke 3D-style bobbing.
* Height and speed of bobbing customisable.
* While it's cleaner in the AIPlayer ticker, AIRa requires its target set (which is done in this func also) and I don't know whether AIPlayer is ticked before AIRa is.
* I tried to make this work in 2020 but its been nothing but headache. It's something for the game to control via a flag, not the backend to determine.
* For SW, this restores its original implementation.
* Ensure's a smooth return to 0 so the player's actual pitch can be targeted towards Ramses.
* In situations where the player had their view pitch changed in the ticker, this would have never reset.
* We can just pass the needed value into `doPlayerPitch()`.
* For Ramses, no need to set `nDestVertPan` to the map value, just use the map value.
* Avoids an excess `atan2()` call by way of `maphoriz()`.
* Was dropped in 572869f502.
* Game's crouch testing necessitates that this value be pre-cached.
* Interestingly, this value is 62.5 whereas the game's view height is 55. Change in late development to make the world feel larger?
* Made it work on the player's view pitch and not their actual pitch.
* Drastically simplifies implementation and allows its use even with mouse aiming.
* Changes implementation in 67c7dd65f9.
* Cannot rely on the actor's velocity alone as parts of the game modify this, such as getting hit by lava dudes, but game nullifies this at the start of the player's tic.
