Three.js：如何在运行时间添加和移除灯光？

Question

我努力了几天，我的代码有什么问题吗？ Three.js 不更新灯光。我的帮助将不胜感激，这可能会解决我的问题。

我尝试了以下代码的很多组合，但都没有成功。

function LightFunc(Light){

      scene.remove(spotLight1);
      scene.remove(spotLight2);
      cubeMaterial.needsUpdate=true;
      planeMaterial.needsUpdate=true;

      if (document.getElementById('Light1').checked) {
        spotLight1 = new THREE.SpotLight(0xffffff);
        spotLight1.position.set(15,30,50);
        spotLight1.castShadow = true;
        scene.add(spotLight1);
      }
      if (document.getElementById('Light2').checked) {
        spotLight2 = new THREE.SpotLight(0xffffff);
        spotLight2.position.set(15,30,-50);
        spotLight2.castShadow = true;
        scene.add(spotLight2);
      }
      }

    // step1: how to create scene
    var scene = new THREE.Scene();

    // step2: how to create camera
    var camera = new THREE.PerspectiveCamera(45, 4/3, .1, 500)
    camera.position.set(40,40,40);
    camera.lookAt(scene.position);

    // step3: how to create renderer
    var renderer = new THREE.WebGLRenderer();
    renderer.setClearColor(0xdddddd);
    renderer.setSize(800, 600);
    renderer.shadowMap.enabled = true;
    renderer.shadowMap.type = THREE.PCFSoftShadowMap;

    // step4: how to create axis
    var axis = new THREE.AxesHelper(10);
    scene.add(axis);

    // step5: how to create color
    var color = new THREE.Color("rgb(255, 0, 0)");

    // step6: how to create grid
    var grid = new THREE.GridHelper(50,5,color,0x000000);
    scene.add(grid);

    // step7: how to create cube
    var cubeGeo = new THREE.BoxGeometry(5,5,5);
    var cubeMaterial = new THREE.MeshLambertMaterial({color:0xff3300});
    var cube = new THREE.Mesh(cubeGeo,cubeMaterial);
    cube.position.set(2.5,2.5,2.5);
    cube.castShadow = true;
    cube.receiveShadow = false;
    scene.add(cube);

    // step8: how to create plane
    var planeGeo = new THREE.PlaneGeometry(30,30,30);
    var planeMaterial = new THREE.MeshLambertMaterial({color:0x00ff00});
    var plane = new THREE.Mesh(planeGeo,planeMaterial);
    plane.rotation.x = -.5*Math.PI;
    plane.receiveShadow = true;
    scene.add(plane);

    // step9: how to create spot lights

    var spotLight1 = new THREE.SpotLight(0xffffff);
    spotLight1.position.set(15,30,50);
    spotLight1.castShadow = true;
    scene.add(spotLight1);

    var spotLight2 = new THREE.SpotLight(0xffffff);
    spotLight2.position.set(15,30,-50);
    spotLight2.castShadow = true;
    scene.add(spotLight2);

    var canvas = document.getElementById("canvas");
    canvas.appendChild(renderer.domElement);
    renderer.render(scene,camera);

<html>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r123/three.min.js"></script>
    <body>
      <div id="canvas" width="800px" height="600px"></div>
      <div>
        <input type="checkbox" id="Light1" name="Light1" value="Light1" onchange="LightFunc();" checked >
        <label for="Light1"> Light1</label><br>
        <input type="checkbox" id="Light2" name="Light2" value="Light2" onchange="LightFunc();" checked >
        <label for="Light2"> Light2</label><br>
      </div>
    </body> 
</html>

我努力了几天，我的代码有什么问题吗？ Three.js 不更新灯光。我的帮助将不胜感激，这可能会解决我的问题。

我尝试了以下代码的很多组合，但都没有成功。

Answer 1

由于您的场景中没有动画循环，因此您必须在更改灯光设置时再次渲染它。

function LightFunc(Light){

      scene.remove(spotLight1);
      scene.remove(spotLight2);
      cubeMaterial.needsUpdate=true;
      planeMaterial.needsUpdate=true;

      if (document.getElementById('Light1').checked) {
        spotLight1 = new THREE.SpotLight(0xffffff);
        spotLight1.position.set(15,30,50);
        spotLight1.castShadow = true;
        scene.add(spotLight1);
      }
      if (document.getElementById('Light2').checked) {
        spotLight2 = new THREE.SpotLight(0xffffff);
        spotLight2.position.set(15,30,-50);
        spotLight2.castShadow = true;
        scene.add(spotLight2);
      }
      renderer.render(scene,camera); // FIX
      }

    // step1: how to create scene
    var scene = new THREE.Scene();

    // step2: how to create camera
    var camera = new THREE.PerspectiveCamera(45, 4/3, .1, 500)
    camera.position.set(40,40,40);
    camera.lookAt(scene.position);

    // step3: how to create renderer
    var renderer = new THREE.WebGLRenderer();
    renderer.setClearColor(0xdddddd);
    renderer.setSize(800, 600);
    renderer.shadowMap.enabled = true;
    renderer.shadowMap.type = THREE.PCFSoftShadowMap;

    // step4: how to create axis
    var axis = new THREE.AxesHelper(10);
    scene.add(axis);

    // step5: how to create color
    var color = new THREE.Color("rgb(255, 0, 0)");

    // step6: how to create grid
    var grid = new THREE.GridHelper(50,5,color,0x000000);
    scene.add(grid);

    // step7: how to create cube
    var cubeGeo = new THREE.BoxGeometry(5,5,5);
    var cubeMaterial = new THREE.MeshLambertMaterial({color:0xff3300});
    var cube = new THREE.Mesh(cubeGeo,cubeMaterial);
    cube.position.set(2.5,2.5,2.5);
    cube.castShadow = true;
    cube.receiveShadow = false;
    scene.add(cube);

    // step8: how to create plane
    var planeGeo = new THREE.PlaneGeometry(30,30,30);
    var planeMaterial = new THREE.MeshLambertMaterial({color:0x00ff00});
    var plane = new THREE.Mesh(planeGeo,planeMaterial);
    plane.rotation.x = -.5*Math.PI;
    plane.receiveShadow = true;
    scene.add(plane);

    // step9: how to create spot lights

    var spotLight1 = new THREE.SpotLight(0xffffff);
    spotLight1.position.set(15,30,50);
    spotLight1.castShadow = true;
    scene.add(spotLight1);

    var spotLight2 = new THREE.SpotLight(0xffffff);
    spotLight2.position.set(15,30,-50);
    spotLight2.castShadow = true;
    scene.add(spotLight2);

    var canvas = document.getElementById("canvas");
    canvas.appendChild(renderer.domElement);
    renderer.render(scene,camera);

<html>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r123/three.min.js"></script>
    <body>
      <div id="canvas" width="800px" height="600px"></div>
      <div>
        <input type="checkbox" id="Light1" name="Light1" value="Light1" onchange="LightFunc();" checked >
        <label for="Light1"> Light1</label><br>
        <input type="checkbox" id="Light2" name="Light2" value="Light2" onchange="LightFunc();" checked >
        <label for="Light2"> Light2</label><br>
      </div>
    </body> 
</html>

Three.js：如何在运行时间添加和移除灯光？

Three.js: How to add and remove lights at run time?

light

three.js