A basic steering behaviors library based on THREE.js. The term 'Steering Behaviors' refers to a set of common AI movement algorithms and was coined by Craig Reynolds in a paper published in 1999.
Include THREE.js library and ThreeSteer:
<script src="libs/three.min.js"></script>
<script src="js/ThreeSteer.js"></script>
Create a basic 3D scene:
<script>
var container;
var camera;
var scene, renderer;
function init(element){
container= document.getElementById(element);
camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 20000);
scene = new THREE.Scene();
renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
container.appendChild(renderer.domElement);
camera.position.set(0, 3000, 3000;
camera.lookAt(new THREE.Vector3(0,0,0))
animate();
}
function animate(){
requestAnimationFrame(animate);
renderer.render(scene, camera);
}
</script>
<body onload="init('container')">
<div id="container"></div>
</body>
Simply instantiate some Steering Entities and add them to the scene. SteeringEntity is only an empty container with the motion logic, you need to pass a visible Object3D to the constructor to see it in action:
var geometry = new THREE.BoxGeometry( 100, 200, 50 );
var material = new THREE.MeshBasicMaterial( { color: 0xFFFFFF, wireframe: true } );
var mesh = new THREE.Mesh(geometry, material);
entity = new SteeringEntity(mesh);
scene.add(entity);
Call the behavior/s and the update method inside main render/animation loop. Eg:
function animate(){
requestAnimationFrame(animate);
entity.seek(point);
entity.lookWhereGoing(true);
entity.update();
renderer.render(scene, camera);
}
Supported Behaviors are:
- Seek
- Flee
- Arrive
- Pursue
- Evade
- Interpose
- Wander
- Collision Avoidance
- Follow Path
- Follow Leader
- Queue
- Cohesion, separation and alignment (Flocking)
Currently the library only moves objects in the x/z direction.