A CodePen by Xanmia. Dynamic Plane Adjusting in threejs - Random adjusting the heights on the plane object. Refresh page for new plane layout.

script.js

var vertexHeight = 500;
var planeDefinition = 20;
var planeSize = 15000;

var container = document.createElement('div');
document.body.appendChild( container );

var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight,1, 20000)
camera.position.z = 6000; 

var scene = new THREE.Scene();

var material = new THREE.MeshBasicMaterial({ color: 0xFFFFFF, wireframe:true });

var	plane = new THREE.Mesh( new THREE.PlaneGeometry( planeSize, planeSize, planeDefinition, planeDefinition ), new THREE.MeshBasicMaterial( { color: 0x555555, wireframe: true } ) );
plane.rotation.x -=1;

scene.add( plane );

var renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
container.appendChild( renderer.domElement );

updatePlane();

 function updatePlane() { 
   for (var i = 0; i < plane.geometry.vertices.length; i++) 
   { 
     plane.geometry.vertices[i].z += Math.random()*vertexHeight -vertexHeight; 
   } 
 };


render();

			function render() {
        requestAnimationFrame( render );
        
        renderer.render( scene, camera );
			}

		
      window.addEventListener( 'resize', onWindowResize, false );

function onWindowResize() {
				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

style.css

body{
  background-color: #000000;
  margin: 0px;
}