How do I put limits on OrbitControl?

OrbitControls source

Zoom in / zoom out

this.minDistance = 0;
this.maxDistance = Infinity;

Where to stop rotation :

this.minPolarAngle = 0; // radians
this.maxPolarAngle = Math.PI; // radians

Don’t let to go below the ground

controls.maxPolarAngle = Math.PI/2;