Calmness is of two types
First- when one maintain calmness that means one try to remain in a specific area of your mind . Yes it’s a good way but when such situations increase manyfold then one explodes.
Attachment or identification to a situation or object or status makes one angry, greedy , miserable, jealous . This all makes one depressed or they go to pubs , have a party ,eat favourite food, meet friends for mood change or buy a new toy to pamper .This is called Artificial calmness.
Second – when one always calm inside no matter what the situation is , always stay in core (the true self)and perform all activities outside in this world. Yes , one display emotions outside but inside you are actually not connected with them . One maintain this calmness without drugs, alcohol, tobacco. Nothing in this world can take your calmness away . This is ecstasy.
This state can be achieved in any situation it makes the person fearless, full of joy and content.