shader202103032130
/
basicshader2.html

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <title>作者博客：百度"three.js 郭隆邦"</title>
  <style>
    body {
      margin: 0;
      overflow: hidden;
    }
  </style>
  <!--引入three.js三维引擎-->
  <script src="http://www.yanhuangxueyuan.com/versions/threejsR92/build/three.js"></script>
</head>

<body>
  <!-- 顶点着色器代码 -->
  <script id="vertexShader" type="x-shader/x-vertex">
    void main(){
      // 逐顶点处理：顶点位置数据赋值给内置变量gl_Position
      gl_Position = vec4( position, 1.0 );
    }
  </script>
  <!-- 片元着色器代码 -->
  <script id="fragmentShader" type="x-shader/x-fragment">
    void main() {
       // 逐片元处理：每个片元或者说像素设置为红色
       gl_FragColor = vec4(1.0,1.0,0.0,1.0);
    }
  </script>
  <script>
    var scene = new THREE.Scene();
    var geometry = new THREE.BoxGeometry(0.5, 0.5, 0.5);
    var material = new THREE.ShaderMaterial({
      vertexShader: document.getElementById('vertexShader').textContent,
      fragmentShader: document.getElementById('fragmentShader').textContent,
    });
    var mesh = new THREE.Mesh(geometry, material);
    scene.add(mesh);

    var width = window.innerWidth; //窗口宽度
    var height = window.innerHeight; //窗口高度
    var k = width / height; //窗口宽高比
    var s = 150; //三维场景显示范围控制系数，系数越大，显示的范围越大
    var camera = new THREE.OrthographicCamera(-s * k, s * k, s, -s, 1, 1000);
    camera.position.set(200, 300, 200); //设置相机位置
    camera.lookAt(scene.position); //设置相机方向(指向的场景对象)
    var renderer = new THREE.WebGLRenderer({
      antialias: true
    });
    renderer.setSize(width, height); //设置渲染区域尺寸
    document.body.appendChild(renderer.domElement); //body元素中插入canvas对象
    function render() {
      renderer.render(scene, camera); //执行渲染操作
      requestAnimationFrame(render); //请求再次执行渲染函数render，渲染下一帧
    }
    render();
  </script>
</body>

</html>