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代码如下：

<script>var viewer = new Cesium.Viewer("cesiumContainer");/** 创建自己的事件处理程序，使相机朝向鼠标的方向，并在按下相应的键时向前后，左右，上下移动。* */var scene = viewer.scene;var canvas = viewer.canvas;canvas.setAttribute('tabindex','0');canvas.onclick = function () {canvas.focus();}var ellipsoid = viewer.scene.globe.ellipsoid;scene.screenSpaceCameraController.enableRotate = false;scene.screenSpaceCameraController.enableTranslate = false;scene.screenSpaceCameraController.enableZoom = false;scene.screenSpaceCameraController.enableTilt = false;scene.screenSpaceCameraController.enableLook = false;//创建变量来记录当前的鼠标位置，以及用于跟踪相机如何移动的标志var startMousePosition;var mousePosition;var flags = {looking : false,moveForward : false,moveBackward : false,moveUp : false,moveDown : false,moveLeft : false,moveRight : false};//处理用户输入事件。可以添加自定义函数，以便在用户输入时执行var handler = new Cesium.ScreenSpaceEventHandler(canvas);handler.setInputAction(function (movement) {flags.looking = true;mousePosition = startMousePosition = Cesium.Cartesian3.clone(movement.position);},Cesium.ScreenSpaceEventType.LEFT_DOWN);handler.setInputAction(function (movement) {mousePosition = movement.endPosition;},Cesium.ScreenSpaceEventType.MOUSE_MOVE);handler.setInputAction(function (position) {flags.looking = false;},Cesium.ScreenSpaceEventType.LEFT_UP);function getFlagForKeyCode(keyCode) {switch (keyCode){case 'W'.charCodeAt(0):return 'moveForward';case 'S'.charCodeAt(0):return 'moveBackward';case 'Q'.charCodeAt(0):return 'moveUp';case "E".charCodeAt(0):return 'moveDown';case "D".charCodeAt(0):return 'moveRight';case 'A'.charCodeAt(0):return 'moveLeft';default:return undefined;}}document.addEventListener('keydown',function (e) {var flagName = getFlagForKeyCode(e.keyCode);if (typeof flagName !== 'undefined'){flags[flagName] = true;}},false);document.addEventListener('keyup',function (e) {var flagName = getFlagForKeyCode(e.keyCode);if (typeof flagName !== 'undefined'){flags[flagName] = false;}},false);//事件发生时更新相机//点击获取坐标，viewer.clock.onTick.addEventListener(function (clock) {var camera = viewer.camera;if (flags.looking){var width = canvas.clientWidth;var height = canvas.clientHeight;var x = (mousePosition.x  - startMousePosition.x) / width;var y = -(mousePosition.y - startMousePosition.y) / height;var lookFactor = 0.05;//如果相机没有在2D模式下，则以弧度沿其上向量的相反方向围绕其右向量旋转camera.lookRight(x * lookFactor);//参数是弧度，这是转换成弧度//如果相机没有在2D模式下，则沿其右向量的相反方向围绕其up轴旋转camera.lookUp(y * lookFactor);//鼠标离中心的距离决定了转弯的速度。靠近中心位置会使相机速度变慢，而离中心越远则相机移动越快var cameraHeight = ellipsoid.cartesianToCartographic(camera.position).height;var moveRate = cameraHeight/100.0;if (flags.moveForward){camera.moveForward(moveRate);}if (flags.moveBackward){camera.moveBackward(moveRate);}if (flags.moveUp){camera.moveUp(moveRate);}if (flags.moveDown){camera.moveDown(moveRate);}if (flags.moveLeft){camera.moveLeft(moveRate);}if (flags.moveRight){camera.moveRight(moveRate);}}})
</script>

如下：

direction 是视线方向，up 是相机的快门键方向，right 是前两个向量 叉乘得到的第三个向量方向，这样组成了三维