//ported from threejs examples
//https://github.com/mrdoob/three.js/blob/master/examples/webgl_instancing_raycast.html
//https://threejs.org/examples/#webgl_instancing_raycast



//load css
            AB.loadCSS ( '/uploads/threeport/main.css' ); 
            AB.newDiv ('container');

            import * as THREE from '/api/threemodule/libs/three.module.js';

          import Stats from '/uploads/threeport/stats.module.js';
            import { GUI } from '/uploads/threejs/dat.gui.module.js';

		import { OrbitControls } from '/uploads/threejs/OrbitControls.js';

			let camera, scene, renderer, stats;

			let mesh;
			const amount = parseInt( window.location.search.substr( 1 ) ) || 10;
			const count = Math.pow( amount, 3 );

			const raycaster = new THREE.Raycaster();
			const mouse = new THREE.Vector2( 1, 1 );

			const color = new THREE.Color();

			init();
			animate();

			function init() {

				camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 0.1, 100 );
				camera.position.set( amount, amount, amount );
				camera.lookAt( 0, 0, 0 );

				scene = new THREE.Scene();

				const light1 = new THREE.HemisphereLight( 0xffffff, 0x000088 );
				light1.position.set( - 1, 1.5, 1 );
				scene.add( light1 );

				const light2 = new THREE.HemisphereLight( 0xffffff, 0x880000, 0.5 );
				light2.position.set( - 1, - 1.5, - 1 );
				scene.add( light2 );

				const geometry = new THREE.IcosahedronGeometry( 0.5, 3 );
				const material = new THREE.MeshPhongMaterial();

				mesh = new THREE.InstancedMesh( geometry, material, count );

				let i = 0;
				const offset = ( amount - 1 ) / 2;

				const matrix = new THREE.Matrix4();

				for ( let x = 0; x < amount; x ++ ) {

					for ( let y = 0; y < amount; y ++ ) {

						for ( let z = 0; z < amount; z ++ ) {

							matrix.setPosition( offset - x, offset - y, offset - z );

							mesh.setMatrixAt( i, matrix );
							mesh.setColorAt( i, color );

							i ++;

						}

					}

				}

				scene.add( mesh );

				//

				const gui = new GUI();
				gui.add( mesh, 'count', 0, count );

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

				new OrbitControls( camera, renderer.domElement );

				stats = new Stats();
				document.body.appendChild( stats.dom );

				window.addEventListener( 'resize', onWindowResize );
				document.addEventListener( 'mousemove', onMouseMove );

			}

			function onWindowResize() {

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

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

			}

			function onMouseMove( event ) {

				event.preventDefault();

				mouse.x = ( event.clientX / window.innerWidth ) * 2 - 1;
				mouse.y = - ( event.clientY / window.innerHeight ) * 2 + 1;

			}

			function animate() {

				requestAnimationFrame( animate );

				render();

			}

			function render() {

				raycaster.setFromCamera( mouse, camera );

				const intersection = raycaster.intersectObject( mesh );

				if ( intersection.length > 0 ) {

					const instanceId = intersection[ 0 ].instanceId;

					mesh.setColorAt( instanceId, color.setHex( Math.random() * 0xffffff ) );
					mesh.instanceColor.needsUpdate = true;

				}

				renderer.render( scene, camera );

				stats.update();

			}