How camera works in 2d platformer in level transitions

I want to know how Camera works in game of Celeste. enter image description here

Currently what I have is, camera follows the player using interpolation:

cameraPosition = cameraPosition + (playerPosition - cameraPosition) * 0.1; 

and I clamp the camera position to the edge of the world size:

cameraPosition = mu.clamp(cameraPosition - [160, 90], 0, worldSize); 

I subtract [160, 90] to center the camera.

This works OK. But is that all there is to it.

Specifically, how does the camera work between room transitions.

I might drop room transitions, and just do a black screen transition between levels, but I’ve heard there is camera triggers that offset the camera relative to player position, and what other tricks are used?