frameStart method

double frameStart(
  1. Duration elapsed,
  2. double deltaSeconds
)

Starts a frame and returns its scaled delta.

Implementation

double frameStart(Duration elapsed, double deltaSeconds) {
  // Advance the profiler frame counter (if profiling is enabled) at the one
  // per-frame boundary, so timings can be attributed to a frame number.
  app.profiler?.beginFrame();
  final world = app.world;
  final clock = world.clock;
  // Apply a partial freeze to its full frame.
  final scaledDelta = deltaSeconds * clock.effectiveScale;
  clock.advanceFreeze(deltaSeconds);
  world.frameTime
    ..delta = scaledDelta
    ..unscaledDelta = deltaSeconds
    ..elapsed = elapsed
    ..frame += 1;
  _latch.advanceFrame(deltaSeconds);
  app.runSchedule(Schedules.frameStart);
  app.applyStateTransitions();
  onCommandBoundary?.call();
  app.updateEvents();
  return scaledDelta;
}