Sunrise Alarm Clock Pattern

Patterns and Code
1

Sunrise Alarm Clock.epe (13.7 KB)

I had a lot of fun writing this pattern to play a little sunrise and sunset and then show something for the rest of the day. Some of it’s probably generally useful as well:

Pattern starts by playing a demo
Because the pattern itself depends on the time of day, and the example isn’t very illustrative of the appearance or effect, I set the pattern to play a quick demo to record the ~10s that gets shown as the preview. This was also useful for testing.

Sunrise

Track milliseconds for smoother operation
One barrier to driving a pattern purely based on the time of day is we only get time functions with resolution down to 1 second, which creates a very slow frame rate. If we’re tracking hours, the 16 bits after the decimal leaves room for 50ms increments. I count milliseconds and syncronize to observations of second rollovers, and then construct a time of day with as much resolution as I can store in hours.

// Getter for ms analagous to clockSecond()
function clockMs() {
  return _ms
}
{
  var _ms
  var _lastSecond
  // Update ms based on delta and observations of clockSecond rollover events
  // Called by beforeRender
  function updateMS(delta){
    if (_lastSecond == clockSecond()){
      _ms+=delta
    } else {
      _lastSecond = clockSecond()
      _ms = min(delta,_ms%1000)
    }
  }
}

I think I can get better resolution in time of day by tracking time of day in minutes (seconds would overflow)

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