Function SK_Unity_UpdateTimingOverrides

src/plugins/unity.cpp:1865–2032

Combined Mono and il2cpp support for setting target framerate and fixed delta time in Unity.

// Combined Mono and il2cpp support for setting target framerate and fixed delta time in Unity.
void
SK_Unity_UpdateTimingOverrides (void)
{
  // The Mono/il2cpp runtime is in a weird state, assume game is shutting down...
  static bool exception_raised = false;

  static HANDLE hSetTargetFramerateSignal =
    SK_CreateEvent (nullptr, FALSE, TRUE, nullptr);

  static HANDLE
    signals [] = {
      hSetTargetFramerateSignal,
      __SK_DLL_TeardownEvent
    };

  static int                         target_fps = -1; // Disable Unity limiter
  static void* params_fps   [1] = { &target_fps };
  static void* params_delta [1] = { &fixed_delta_time_static };

  if (__target_fps_now > 0.0f || fixed_delta_time_static != 0.0f)
  {
    if (! ReadAcquire (&__SK_DLL_Ending))
      SetEvent (hSetTargetFramerateSignal);

    static volatile LONG             timing_thread  =  0;
    if (InterlockedCompareExchange (&timing_thread, 1, 0) == 0)
    {
      // This thread is full of awful hacks because SK does not know when
      //   Unity is shutting down and the Managed runtime waits for all
      //     attached threads to terminate during a clean exit.
      //
      //   It could all be a lot simpler, but we must avoid attaching
      //     the managed runtime to the thread that signals this code.
      SK_Thread_CreateEx ([](LPVOID)->DWORD
      {
        SK_Thread_SetCurrentPriority (THREAD_PRIORITY_LOWEST);

        bool attached = false;
        bool il2cpp   = false;
        bool mono     = false;

        while (! ReadAcquire (&__SK_DLL_Ending))
        {
          if (exception_raised)
            break;

          il2cpp = (set_targetFrameRate_il2cpp != nullptr||
                    set_fixedDeltaTime_il2cpp  != nullptr);

          mono   = (set_targetFrameRate_mono != nullptr||
                    set_fixedDeltaTime_mono  != nullptr);

          const auto last_frame =
            SK_GetFramesDrawn ();

          DWORD dwWaitState =
            WaitForMultipleObjects (2, signals, FALSE, 666);