The SHA256 was effectively not optional anymore when recording demos, as it and the SHA256 extension UUID were always written to the demo file without checking for `nullptr`. Therefore the SHA256 is now passed by const reference instead of by pointer and redundant checks for `nullptr` are removed.
The client/server jobpools were previously only using a fixed number of 2 threads. Now the pools use `2 * hardware-concurrency + 2` threads, which should provide better performance overall, as we expect threads to often wait on I/O.
Previously all demo players checked `IVideo::Current` to render a video, which would cause issues when rendering a demo while a demo slicing background job is running. Now video rendering can be toggled for each demo player individually and is only enabled for the main demo player.
The TODO in the `Dilate` function is removed, as the code already appears to be safe without additional checks. The variable `k` is at most `(w * h - 1) * BPP`, as `ix` and `iy` are clamped to maximum `w - 1` and `h - 1` respectively. Because `p < BPP - 1` the index `k + p` is therefore always valid for the buffers. (The caller must ensure that the source and destination buffers are of size `w * h * BPP`.)
Use config manager to reset `ui_page` to the default, instead of using `CMenus::PAGE_DDNET` directly (which is the default).
Check current type of serverbrowser instead of checking the current `ui_page` against `CMenus::PAGE_DDNET` and `CMenus::PAGE_KOG`.
Using `dbg_stress 1` now only does the following (in debug build):
- Randomly send inputs.
- Randomly send chat messages.
- Randomly connect/disconnect to server configured with `dbg_stress_server` (`localhost` by default).
Previously it also did the following, which is not useful for this debugging feature and only complicates the code unnecessarily:
- Cause images and sounds not to be loaded.
- Render only every tenth frame.
- Always use inactive graphics refresh rate.
Instead of keeping track of a permanently empty `CSnapshot` object in client and server separately, add `CSnapshot::EmptySnapshot` to access a singleton empty `CSnapshot`.
Mark pointer parameters of snapshot functions as `const` when possible.
Simplify the handling of free texture indices by using `-1` only for indices which are currently in use, whereas the size of the vector is now used to indicate the last free index. Otherwise the assertions incorrectly detect the last texture index always being in use because `-1` was used for both states.
Most variables used in the sound engine were static globals, as they are used in the static sound mixing function. The global variables are replaced by member variables, by passing the sound interface as user-data for the SDL mixing callback. The `Mix` function is made a public member function of `ISound` instead of being exposed using `ISoundMixFunc GetSoundMixFunc()`.
This allows to remove the direct dependency of the engine sound on the engine video, by instead passing the sound mixing function as a lambda to the engine video in the engine client.
The old WavPack reader function interface does support passing a user-data pointer to the callback function, so global variables are still used here.
