Place a directional light in scene, movable mobility
Rotation in Y axis (Pitch Value):
0-180 degree is night
181-360 is day
Open the Map level BP, add the timeline node, called DayNight Cycle
Open it. change length to 30 sec, Add Float Check (since only Y axis value has to change)
Add 2 keyframe:
time 0, value 0
time 30, value 360 (i.e. 15 sec in day, 15 sec at night)
Name as SunDirection
Create reference to the timeline node, then connect to actor rotation
Can change X (roll value) if want the sun direction changes
Turn on loop if want to the time lapse go continuously
To turn on/off street lights to fit the day/night (by using Event Dispatcher):