// Задача: Направете топката да се движи в
// равнината XZ, като рикошира от стените.


var renderer = new THREE.WebGLRenderer({antialias:true});
renderer.setSize( window.innerWidth, window.innerHeight );
renderer.setAnimationLoop( drawFrame );
document.body.appendChild( renderer.domElement );

renderer.shadowMap.enabled = true;
renderer.shadowMap.type = THREE.PCFSoftShadowMap;

var scene = new THREE.Scene();
scene.background = new THREE.Color( 'skyblue' );

var aspect = window.innerWidth/window.innerHeight;
var camera = new THREE.PerspectiveCamera( 30, aspect );
camera.position.set( 0, 120, 200 );
camera.lookAt( new THREE.Vector3( 0, -10, 0 ) );


// топчето за движене
var ball = new THREE.Mesh(
	new THREE.SphereGeometry( 5, 32, 32 ),
	new THREE.MeshPhongMaterial( {color: 'orange', shininess: 10, specular: 'white', emissive: 'firebrick'} )
);
ball.castShadow = true;
scene.add( ball );

// платформата
var ground = new THREE.Mesh(
	new THREE.BoxGeometry( 160.2, 2.2, 100.2 ),
	new THREE.MeshPhongMaterial( {color: 'slateblue', shininess: 2, specular: 'white'} )
);
ground.position.y = -6;
ground.receiveShadow = true;
scene.add( ground );
		
// стъкленият корпус
var glass = new THREE.Mesh(
	new THREE.BoxGeometry( 160, 10, 100 ),
	new THREE.MeshPhongMaterial( {color: 'azure', opacity: 0.2, transparent: true, shininess: 50, specular: 0x8080ff, side:THREE.BackSide} )
);
glass.receiveShadow = true;
scene.add( glass );

// бялата рамка на стъкления корпус
var frame = new THREE.BoxHelper( glass );
frame.material.color.set( 'white' );
scene.add( frame );
		
// светлина
var light = new THREE.PointLight( 'white', 0.5 );
light.position.set( 0, 100, 0 );
light.castShadow = false;
scene.add( light );

// и още една
var light = new THREE.PointLight();
light.position.set( 0, 20, 0 );
light.castShadow = true;
scene.add( light );

function absVec(v) {
	return new THREE.Vector3(Math.abs(v.x), Math.abs(v.y), Math.abs(v.z));
}
function lessThanV(v1, v2) {
	return new THREE.Vector3(-1+2*(v1.x < v2.x), -1+2*(v1.y < v2.y), -1+2*(v1.z < v2.z));
}
var movementV = new THREE.Vector3(1, 0, 0.5);
var edgeV = new THREE.Vector3(80, 0, 50);
	
function drawFrame()
{
	scene.rotation.y += 0.001;
	movementV.multiply(lessThanV(absVec(ball.position).addScalar(5), edgeV));
	ball.position.add(movementV);

	renderer.render( scene, camera );
}