How do I put limits on OrbitControl?

Question

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; 

Just in case someone needs a a more robust answer with ground altitude and camera target adjustment:

You find the angle relative to the controls target and the ground position of the camera (regardless of altitude) and assign the maxPolarAngle. Adjust for your up axis, mine was Y. Inside the controls change event:

var centerPosition = controls.target.clone();
centerPosition.y = 0;
var groundPosition = camera.position.clone();
groundPosition.y = 0;
var d = (centerPosition.distanceTo(groundPosition));

var origin = new THREE.Vector2(controls.target.y,0);
var remote = new THREE.Vector2(0,d); // replace 0 with raycasted ground altitude
var angleRadians = Math.atan2(remote.y - origin.y, remote.x - origin.x);
controls.maxPolarAngle = angleRadians;

If you want more control over Orbit:

        const controls = new OrbitControls(camera, this.renderer.domElement);
        controls.enableDamping = true;   //damping 
        controls.dampingFactor = 0.25;   //damping inertia
        controls.enableZoom = true;      //Zooming
        controls.autoRotate = true;       // enable rotation
        controls.maxPolarAngle = Math.PI / 2; // Limit angle of visibility
        controls.keys = {
          LEFT: 37, //left arrow
          UP: 38, // up arrow
          RIGHT: 39, // right arrow
          BOTTOM: 40 // down arrow
        };
    
       controls.addEventListener("change", () => {
          if (this.renderer) this.renderer.render(this.scene, camera);
        });