Three.js Fat Line Runaway Memory

by IdreesInc

CSS

body {
	background-color: #000;
	margin: 0px;
	overflow: hidden;
}

JavaScript

// Simple three.js example

import * as THREE from "https://threejs.org/build/three.module.js";
import { OrbitControls } from "https://threejs.org/examples/jsm/controls/OrbitControls.js";//threejs.org/examples/jsm/lines/Line2.js";
import { Line2 } from "https://threejs.org/examples/jsm/lines/Line2.js";
import { LineGeometry } from "https://threejs.org/examples/jsm/lines/LineGeometry.js";
import { LineMaterial } from "https://threejs.org/examples/jsm/lines/LineMaterial.js";

var mesh, renderer, scene, camera, controls;

let renderedLines = [];

init();
animate();

function init() {

    // renderer
    renderer = new THREE.WebGLRenderer();
    renderer.setSize( window.innerWidth, window.innerHeight );
    renderer.setPixelRatio( window.devicePixelRatio );
    document.body.appendChild( renderer.domElement );

    // scene
    scene = new THREE.Scene();
    
    // camera
    camera = new THREE.PerspectiveCamera( 40, window.innerWidth / window.innerHeight, 1, 10000 );
    camera.position.set( 20, 20, 20 );

    // controls
    controls = new OrbitControls( camera, renderer.domElement );
   
    
    let lineMaterial = new LineMaterial({
			color: 0xffffff,
			linewidth: 0.2,
			worldUnits: true,
			alphaToCoverage: true,
		});
    
    for (let i = 0; i < 50; i++) {
      let lineGeo = new LineGeometry();
      let renderedLine = new Line2(lineGeo, lineMaterial);
      renderedLine.scale.set(1, 1, 1);
      renderedLine.geometry.setPositions([0, 0, 0, 10, 0, 10]);
      renderedLines.push(renderedLine);
      scene.add(renderedLine);
    }
    
}

function animate() {

    requestAnimationFrame( animate );
    
    for (let renderedLine of renderedLines) {
    // Commenting out this line prevents the memory from increasing
    	renderedLine.geometry.setPositions([0, 0, 0, 10, 0, 10]);  
    }
    
    //controls.update();

    renderer.render( scene, camera );

}