three.js平面几何体之旋转

时间:2021-10-31 04:47:23
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>旋转</title>
    <style type="text/css">
        div#canvas-frame {
            border: none;
            cursor: pointer;
            width: 100%;
            height: 600px;
            background-color: #EEEEEE;
        }
    </style>
    <script type="text/javascript" src="js/three.js"></script>
    <script src="js/stats.min.js"></script>
    <script src="js/tween.min.js"></script>
    <script>
        var renderer,stats;
         //照相机配置
        var fov = 45,//拍摄距离 视野角值越大,场景中的物体越小
        near = 1,//最小范围
        far = 1000;//最大范围
        //var canvas = document.getElementById('canvas-frame');
        function initThree(){
            width = document.getElementById('canvas-frame').clientWidth;
            height = document.getElementById('canvas-frame').clientHeight;
            renderer = new THREE.WebGLRenderer({
                antialias:true
            });
            renderer.setSize(width, height);
            document.getElementById('canvas-frame').appendChild(renderer.domElement);
            renderer.setClearColor(0xFFFFFF, 1.0);

            stats = new Stats();
            stats.domElement.style.position = 'absolute';
            stats.domElement.style.left = '0px';
            stats.domElement.style.top = '0px';
            document.getElementById('canvas-frame').appendChild(stats.domElement);
        }

        var camera;
        function initCamera() {
            camera = new THREE.PerspectiveCamera(fov, width / height, near, far);
            camera.position.x = 100;
            camera.position.y = 300;
            camera.position.z = 600;
            camera.up.x = 0;
            camera.up.y = 1;
            camera.up.z = 0;
            camera.lookAt({
                x : 0,
                y : 0,
                z : 0
            });
        }

        var scene;
        function initScene() {
            scene = new THREE.Scene();
        }

        var light;
        function initLight() {
            light = new THREE.AmbientLight(0xFF0000);
            light.position.set(100, 100, 200);
            scene.add(light);

        }

        var cube;
        var mesh;
        function initObject() {
            
            var geometry = new THREE.BoxGeometry( 100, 100, 100 );
            
            for ( var i = 0; i < geometry.faces.length; i += 2 ) {

                var hex = Math.random() * 0xffffff;
                geometry.faces[ i ].color.setHex( hex );
                geometry.faces[ i + 1 ].color.setHex( hex );

            }
            
            var material = new THREE.MeshBasicMaterial( { vertexColors: THREE.FaceColors} );
            mesh = new THREE.Mesh( geometry,material);
            mesh.position = new THREE.Vector3(0,0,0);
            scene.add(mesh);
            
            
        }
        
        function initGrid(){
            var helper = new THREE.GridHelper( 1000, 50 );
            helper.setColors( 0x0000ff, 0x808080 );
            scene.add( helper );
        }
        
        function threeStart() {
            initThree();
            initCamera();
            initScene();
            initLight();


            initObject();
            initGrid();
            
            animation();
            document.getElementById('canvas-frame').addEventListener('mousewheel',mousewheel,false);
        }

        // 帧循环、游戏循环
        function animation()
        {
            // mesh.rotation.y +=0.01;
            // renderer.render(scene, camera);
            // requestAnimationFrame(animation);
            //相机围绕y轴旋转,并且保持场景中的物体一直再相机的视野中
            //实时渲染成像
            var timer = Date.now()*0.0001;
            camera.position.x = Math.cos(timer)*100;
            camera.position.z = Math.sin(timer)*100;
            camera.lookAt(scene.position);
            renderer.render(scene, camera);
            requestAnimationFrame(animation);

        }

        function mousewheel(e){
            e.preventDefault();
            if(e.wheelDelta){
                //判断浏览器是谷歌、ie滑轮事件
                if(e.wheelDelta > 0){
                    //滑轮向上滚动
                    fov -=(near < fov ? 1 : 0);
                } 
                if (e.wheelDelta < 0) { //当滑轮向下滚动时
                    fov += (fov < far ? 1 : 0);
                }
            }else if(e.detail){//firefox滑轮事件
                if (e.detail > 0) { //当滑轮向上滚动时
                    fov -= 1;
                }
                if (e.detail < 0) { //当滑轮向下滚动时
                    fov += 1;
                }
            }
            //改变fov值,并更新场景的渲染
            camera.fov = fov;
            camera.updateProjectionMatrix();
            renderer.render(scene, camera);
        }


    </script>
</head>
<body onload="threeStart()">
    <div id="canvas-frame"></div>
</body>
</html>

上述是代码,下面效果图如下:

three.js平面几何体之旋转