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<head>
<title>three.js webgl - buffergeometry - lines - indexed</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
<style>
body {
color: #cccccc;
font-family:Monospace;
font-size:13px;
text-align:center;
background-color: #000000;
margin: 0px;
overflow: hidden;
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#info {
position: absolute;
top: 0px; width: 100%;
padding: 5px;
}
a {
color: #0080ff;
}
</style>
</head>
<body>
<div id="container"></div>
<div id="info"><a href="http://threejs.org" target="_blank">three.js</a> webgl - buffergeometry - lines - indexed</div>
<script src="../build/three.min.js"></script>
<script src="js/Detector.js"></script>
<script src="js/libs/stats.min.js"></script>
<script>
if ( ! Detector.webgl ) Detector.addGetWebGLMessage();
var container, stats;
var camera, scene, renderer;
var mesh, parent_node;
init();
animate();
function init() {
container = document.getElementById( 'container' );
camera = new THREE.PerspectiveCamera( 27, window.innerWidth / window.innerHeight, 1, 10000 );
camera.position.z = 9000;
scene = new THREE.Scene();
var geometry = new THREE.BufferGeometry();
var material = new THREE.LineBasicMaterial({ vertexColors: THREE.VertexColors });
var positions = [];
var next_positions_index = 0;
var colors = [];
var indices_array = [];
//
var iteration_count = 4;
var rangle = 60 * Math.PI / 180.0;
function add_vertex(v) {
if (next_positions_index == 0xffff) throw new Error("Too many points");
positions.push(v.x, v.y, v.z);
colors.push(Math.random()*0.5+0.5, Math.random()*0.5+0.5, 1);
return next_positions_index++;
}
// simple Koch curve
function snowflake_iteration(p0, p4, depth) {
if (--depth < 0) {
var i = next_positions_index-1; // p0 already there
add_vertex(p4);
indices_array.push(i, i+1);
return;
}
var v = p4.clone().sub(p0);
var v_tier = v.clone().multiplyScalar(1.0/3.0);
var p1 = p0.clone().add(v_tier);
var angle = Math.atan2(v.y, v.x) + rangle;
var length = v_tier.length();
var p2 = p1.clone();
p2.x += Math.cos(angle) * length;
p2.y += Math.sin(angle) * length;
var p3 = p0.clone().add(v_tier).add(v_tier);
snowflake_iteration(p0, p1, depth);
snowflake_iteration(p1, p2, depth);
snowflake_iteration(p2, p3, depth);
snowflake_iteration(p3, p4, depth);
}
function snowflake(points, loop, x_offset) {
for (var iteration = 0; iteration != iteration_count; ++iteration) {
add_vertex(points[0]);
for (var p_index=0, p_count=points.length-1; p_index != p_count; ++p_index) {
snowflake_iteration(points[p_index], points[p_index+1], iteration);
}
if (loop) snowflake_iteration(points[points.length-1], points[0], iteration);
// translate input curve for next iteration
for (var p_index=0, p_count=points.length; p_index != p_count; ++p_index) {
points[p_index].x += x_offset;
}
}
}
var y = 0;
snowflake
(
[
new THREE.Vector3(0, y+0, 0),
new THREE.Vector3(500, y+0, 0)
],
false, 600
);
y += 600;
snowflake
(
[
new THREE.Vector3(0, y+0, 0),
new THREE.Vector3(250, y+400, 0),
new THREE.Vector3(500, y+0, 0)
],
true, 600
);
y += 600;
snowflake
(
[
new THREE.Vector3(0, y+0, 0),
new THREE.Vector3(500, y, 0),
new THREE.Vector3(500, y+500, 0),
new THREE.Vector3(0, y+500, 0),
],
true, 600
);
y += 1000;
snowflake
(
[
new THREE.Vector3(250, y+0, 0),
new THREE.Vector3(500, y+0, 0),
new THREE.Vector3(250, y+0, 0),
new THREE.Vector3(250, y+250, 0),
new THREE.Vector3(250, y+0, 0),
new THREE.Vector3(0, y, 0),
new THREE.Vector3(250, y+0, 0),
new THREE.Vector3(250, y-250, 0),
new THREE.Vector3(250, y+0, 0),
],
false, 600
);
// --------------------------------
geometry.addAttribute( 'index', new THREE.BufferAttribute( new Uint16Array( indices_array ), 1 ) );
geometry.addAttribute( 'position', new THREE.BufferAttribute( new Float32Array( positions ), 3 ) );
geometry.addAttribute( 'color', new THREE.BufferAttribute( new Float32Array( colors ), 3 ) );
geometry.computeBoundingSphere();
mesh = new THREE.Line( geometry, material, THREE.LinePieces );
mesh.position.x -= 1200;
mesh.position.y -= 1200;
parent_node = new THREE.Object3D();
parent_node.add(mesh);
scene.add( parent_node );
renderer = new THREE.WebGLRenderer( { antialias: false } );
renderer.setPixelRatio( window.devicePixelRatio );
renderer.setSize( window.innerWidth, window.innerHeight );
renderer.gammaInput = true;
renderer.gammaOutput = true;
container.appendChild( renderer.domElement );
//
stats = new Stats();
stats.domElement.style.position = 'absolute';
stats.domElement.style.top = '0px';
container.appendChild( stats.domElement );
//
window.addEventListener( 'resize', onWindowResize, false );
}
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize( window.innerWidth, window.innerHeight );
}
//
function animate() {
requestAnimationFrame( animate );
render();
stats.update();
}
function render() {
var time = Date.now() * 0.001;
//mesh.rotation.x = time * 0.25;
//mesh.rotation.y = time * 0.5;
parent_node.rotation.z = time * 0.5;
renderer.render( scene, camera );
}
</script>
</body>
</html>