JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r71/three.min.js"></script>
<canvas id="triangles"></canvas>

JavaScript

var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 1, 1000);

var renderer = new THREE.WebGLRenderer({
  alpha: true,
  antialias: true,
  canvas: document.getElementById('triangles')
});
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.setClearColor(0xffffff, 1);

camera.position.z = 10;

drawTriangle(
  new THREE.Vector3(0, 10, 0),
  new THREE.Vector3(-5, -0, 0),
  new THREE.Vector3(0,1,1)
);

renderer.render(scene, camera);

function drawTriangle (vertex1, vertex2, vertex3) {
  var triangleGeometry = new THREE.Geometry();
  var triangleMaterial = new THREE.MeshBasicMaterial({
    color: 0x000000,
    wireframe: true,
    wireframeLinewidth: 1
  });
  var triangle = new THREE.Mesh(triangleGeometry, triangleMaterial);

  triangleGeometry.vertices = [vertex1, vertex2, vertex3];
  triangleGeometry.faces.push(new THREE.Face3(0, 1, 2));

  THREE.GeometryUtils.center(triangleGeometry);

  scene.add(triangle);

  return triangle;
}