title: Three js and react button above canvas
body: <p>this is my three.js code in react, I want to add button above this canvas..
  How can I do??
  Also, How can I add click event on my object?</p>
  <pre><code>import React, { Component } from 'react'
      import * as THREE from 'three'
      //import Button from '@material-ui/core/Button';
  
      class Scene extends Component {
      constructor(props) {
      super(props)
  
      this.start = this.start.bind(this)
      this.stop = this.stop.bind(this)
      this.animate = this.animate.bind(this)
      }
  
      componentDidMount() {
      const sizes = {
          width : window.innerWidth,
          height : window.innerHeight
      }
  
      const scene = new THREE.Scene()
  
      window.addEventListener('resize', () =&gt;
      {
      // Update sizes
      sizes.width = window.innerWidth
      sizes.height = window.innerHeight
  
      // Update camera
      camera.aspect = sizes.width / sizes.height
      camera.updateProjectionMatrix()
  
      // Update renderer
      renderer.setSize(sizes.width, sizes.height)
      renderer.setPixelRatio(Math.min(window.devicePixelRatio, 2))
      })
  
      const renderer = new THREE.WebGLRenderer({ antialias: true })
      const geometry = new THREE.BoxGeometry(1, 1, 1, 10, 10, 10 );
      const particlesGeometry = new THREE.BufferGeometry();
      const particlesCnt = 8000;
  
      const posArray = new Float32Array(particlesCnt * 3);
  
      for (let i=0; i&lt; particlesCnt *3; i++) {
      posArray[i] = (Math.random() - 0.5 ) *5
      }
  
      particlesGeometry.setAttribute('position', new THREE.BufferAttribute(posArray, 3));
      
      const material = new THREE.PointsMaterial({
          size: 0.005
      })
  
      // Texture Loader
      const loader = new THREE.TextureLoader()
      const star = loader.load('./star.png')
      const particlesMaterial = new THREE.PointsMaterial({
          size: 0.005,
          map: star,
          transparent: true,
          //color: 'blue'
          //bleding: THREE.AdditiveBlending
      })
      
      const cube = new THREE.Points(geometry, material)
      const particlesMesh = new THREE.Points(particlesGeometry, particlesMaterial);
      scene.add(cube, particlesMesh)
  
      const pointLight = new THREE.PointLight(0xffffff, 0.1)
      pointLight.position.x = 2
      pointLight.position.y = 3
      pointLight.position.z = 4
      scene.add(pointLight)
  
      //camera.position.z = 4
      // scene.add(cube)
      // renderer.setClearColor('#000000')
  
      
      const camera = new THREE.PerspectiveCamera(75, sizes.width /sizes.height, 0.1, 100)
      camera.position.x = 0
      camera.position.y = 0
      camera.position.z = 2
      scene.add(camera)
  
      renderer.setSize(sizes.width, sizes.height)
  
      this.scene = scene
      this.camera = camera
      this.renderer = renderer
      this.material = material
      this.cube = cube
      this.particlesMesh = particlesMesh
  
      this.mount.appendChild(this.renderer.domElement)
      this.start()
      }
  
      componentWillUnmount() {
      this.stop()
      this.mount.removeChild(this.renderer.domElement)
      }
  
      start() {
      if (!this.frameId) {
        this.frameId = requestAnimationFrame(this.animate)
      }
      }
  
      stop() {
      cancelAnimationFrame(this.frameId)
      }
  
      animate() {
      //this.cube.rotation.x += 0.01
      this.cube.rotation.y += 0.01
      this.particlesMesh.rotation.y += 0.01
  
      this.renderScene()
      this.frameId = window.requestAnimationFrame(this.animate)
      
      }
  
      renderScene() {
      this.renderer.render(this.scene, this.camera)
      }
  
      render() {
      return (
        &lt;div
          style={{ width: '400px', height: '400px' }}
          ref={(mount) =&gt; { this.mount = mount }}
        &gt;
            &lt;/div&gt;
      )
      }
      }
  
      export default Scene
  </code></pre>
  <p>this is my three.js code in react, I want to add button above this canvas..
  How can I do??
  Also, How can I add click event on my object in threejs?</p>
  <p>Thank you for your Help!</p>