# Scene

#### new Cesium.Scene(options)
Scene/Scene.js 160

The container for all 3D graphical objects and state in a Cesium virtual scene. Generally, a scene is not created directly; instead, it is implicitly created by `CesiumWidget`.

`contextOptions` parameter details:

The default values are: `{ webgl : { alpha : false, depth : true, stencil : false, antialias : true, powerPreference: 'high-performance', premultipliedAlpha : true, preserveDrawingBuffer : false, failIfMajorPerformanceCaveat : false }, allowTextureFilterAnisotropic : true }`

The `webgl` property corresponds to the WebGLContextAttributes object used to create the WebGL context.

`webgl.alpha` defaults to false, which can improve performance compared to the standard WebGL default of true. If an application needs to composite Cesium above other HTML elements using alpha-blending, set `webgl.alpha` to true.

The other `webgl` properties match the WebGL defaults for WebGLContextAttributes.

`allowTextureFilterAnisotropic` defaults to true, which enables anisotropic texture filtering when the WebGL extension is supported. Setting this to false will improve performance, but hurt visual quality, especially for horizon views.

Name | Type | Description
--- | --- | ---
`options` | Object | optional Object with the following properties:
Name | Type | Default | Description
--- | --- | --- | ---
`canvas` | HTMLCanvasElement |  | The HTML canvas element to create the scene for.
`contextOptions` | Object |  | optional Context and WebGL creation properties. See details above.
`creditContainer` | Element |  | optional The HTML element in which the credits will be displayed.
`creditViewport` | Element |  | optional The HTML element in which to display the credit popup. If not specified, the viewport will be a added as a sibling of the canvas.
`mapProjection` | MapProjection | `new GeographicProjection()` | optional The map projection to use in 2D and Columbus View modes.
`orderIndependentTranslucency` | Boolean | `true` | optional If true and the configuration supports it, use order independent translucency.
`scene3DOnly` | Boolean | `false` | optional If true, optimizes memory use and performance for 3D mode but disables the ability to use 2D or Columbus View.
`shadows` | Boolean | `false` | optional Determines if shadows are cast by light sources.
`mapMode2D` | MapMode2D | `MapMode2D.INFINITE_SCROLL` | optional Determines if the 2D map is rotatable or can be scrolled infinitely in the horizontal direction.
`requestRenderMode` | Boolean | `false` | optional If true, rendering a frame will only occur when needed as determined by changes within the scene. Enabling improves performance of the application, but requires using `Scene#requestRender` to render a new frame explicitly in this mode. This will be necessary in many cases after making changes to the scene in other parts of the API. See Improving Performance with Explicit Rendering.
`maximumRenderTimeChange` | Number | `0.0` | optional If requestRenderMode is true, this value defines the maximum change in simulation time allowed before a render is requested. See Improving Performance with Explicit Rendering.

##### Throws:

- DeveloperError : options and options.canvas are required.

##### Example:

    // Create scene without anisotropic texture filtering
    var scene = new Cesium.Scene({
      canvas : canvas,
      contextOptions : {
        allowTextureFilterAnisotropic : false
      }
    });

##### See:

- CesiumWidget
- WebGLContextAttributes

### Members

#### backgroundColor : Color
Scene/Scene.js 349

The background color, which is only visible if there is no sky box, i.e., `Scene#skyBox` is undefined.

Default Value: ``Color.BLACK``

##### See:

- Scene#skyBox

#### readonly camera : Camera
Scene/Scene.js 987

Gets or sets the camera.

#### readonly cameraUnderground : Boolean
Scene/Scene.js 1610

Whether or not the camera is underneath the globe.

Default Value: `false`

#### readonly canvas : HTMLCanvasElement
Scene/Scene.js 780

Gets the canvas element to which this scene is bound.

#### readonly clampToHeightSupported : Boolean
Scene/Scene.js 887

Returns `true` if the `Scene#clampToHeight` and `Scene#clampToHeightMostDetailed` functions are supported.

##### See:

- Scene#clampToHeight
- Scene#clampToHeightMostDetailed

#### completeMorphOnUserInput : Boolean
Scene/Scene.js 282

Determines whether or not to instantly complete the scene transition animation on user input.

Default Value: `true`

#### debugCommandFilter : function
Scene/Scene.js 427

This property is for debugging only; it is not for production use.

A function that determines what commands are executed. As shown in the examples below, the function receives the command's `owner` as an argument, and returns a boolean indicating if the command should be executed.

The default is `undefined`, indicating that all commands are executed.

Default Value: `undefined`

##### Example:

    // Do not execute any commands.
    scene.debugCommandFilter = function(command) {
        return false;
    };

    // Execute only the billboard's commands.  That is, only draw the billboard.
    var billboards = new Cesium.BillboardCollection();
    scene.debugCommandFilter = function(command) {
        return command.owner === billboards;
    };

#### readonly debugFrustumStatistics : Object
Scene/Scene.js 1326

This property is for debugging only; it is not for production use.

When `Scene.debugShowFrustums` is `true`, this contains properties with statistics about the number of command execute per frustum. `totalCommands` is the total number of commands executed, ignoring overlap. `commandsInFrustums` is an array with the number of times commands are executed redundantly, e.g., how many commands overlap two or three frustums.

Default Value: `undefined`

#### debugShowCommands : Boolean
Scene/Scene.js 441

This property is for debugging only; it is not for production use.

When `true`, commands are randomly shaded. This is useful for performance analysis to see what parts of a scene or model are command-dense and could benefit from batching.

Default Value: `false`

#### debugShowDepthFrustum : Number
Scene/Scene.js 494

This property is for debugging only; it is not for production use.

Indicates which frustum will have depth information displayed.

Default Value: `1`

#### debugShowFramesPerSecond : Boolean
Scene/Scene.js 470

This property is for debugging only; it is not for production use.

Displays frames per second and time between frames.

Default Value: `false`

#### debugShowFrustumPlanes : Boolean
Scene/Scene.js 506

This property is for debugging only; it is not for production use.

When `true`, draws outlines to show the boundaries of the camera frustums

Default Value: `false`

#### debugShowFrustums : Boolean
Scene/Scene.js 458

This property is for debugging only; it is not for production use.

When `true`, commands are shaded based on the frustums they overlap. Commands in the closest frustum are tinted red, commands in the next closest are green, and commands in the farthest frustum are blue. If a command overlaps more than one frustum, the color components are combined, e.g., a command overlapping the first two frustums is tinted yellow.

Default Value: `false`

#### debugShowGlobeDepth : Boolean
Scene/Scene.js 482

This property is for debugging only; it is not for production use.

Displays depth information for the indicated frustum.

Default Value: `false`

#### readonly drawingBufferHeight : Number
Scene/Scene.js 795

The drawingBufferHeight of the underlying GL context.

##### See:

- drawingBufferHeight

#### readonly drawingBufferWidth : Number
Scene/Scene.js 810

The drawingBufferHeight of the underlying GL context.

##### See:

- drawingBufferHeight

#### eyeSeparation : Number
Scene/Scene.js 601

The eye separation distance in meters for use with cardboard or WebVR.

#### farToNearRatio : Number
Scene/Scene.js 375

The far-to-near ratio of the multi-frustum when using a normal depth buffer.

This value is used to create the near and far values for each frustum of the multi-frustum. It is only used when `Scene#logarithmicDepthBuffer` is `false`. When `logarithmicDepthBuffer` is `true`, use `Scene#logarithmicDepthFarToNearRatio`.

Default Value: `1000.0`

#### focalLength : Number
Scene/Scene.js 595

The focal length for use when with cardboard or WebVR.

#### fog : Fog
Scene/Scene.js 557

Blends the atmosphere to geometry far from the camera for horizon views. Allows for additional performance improvements by rendering less geometry and dispatching less terrain requests.

#### gamma : Number
Scene/Scene.js 1562

The value used for gamma correction. This is only used when rendering with high dynamic range.

Default Value: `2.2`

#### globe : Globe
Scene/Scene.js 929

Gets or sets the depth-test ellipsoid.

#### readonly groundPrimitives : PrimitiveCollection
Scene/Scene.js 974

Gets the collection of ground primitives.

#### highDynamicRange : Boolean
Scene/Scene.js 1577

Whether or not to use high dynamic range rendering.

Default Value: `true`

#### readonly highDynamicRangeSupported : Boolean
Scene/Scene.js 1596

Whether or not high dynamic range rendering is supported.

Default Value: `true`

#### readonly id : String
Scene/Scene.js 1364

Gets the unique identifier for this scene.

#### readonly imageryLayers : ImageryLayerCollection
Scene/Scene.js 1141

Gets the collection of image layers that will be rendered on the globe.

#### imagerySplitPosition : Number
Scene/Scene.js 1505

Gets or sets the position of the Imagery splitter within the viewport. Valid values are between 0.0 and 1.0.

#### invertClassification : Boolean
Scene/Scene.js 577

When `false`, 3D Tiles will render normally. When `true`, classified 3D Tile geometry will render normally and unclassified 3D Tile geometry will render with the color multiplied by `Scene#invertClassificationColor`.

Default Value: `false`

#### invertClassificationColor : Color
Scene/Scene.js 586

The highlight color of unclassified 3D Tile geometry when `Scene#invertClassification` is `true`.

When the color's alpha is less than 1.0, the unclassified portions of the 3D Tiles will not blend correctly with the classified positions of the 3D Tiles.

Also, when the color's alpha is less than 1.0, the WEBGL_depth_texture and EXT_frag_depth WebGL extensions must be supported.

Default Value: `Color.WHITE`

#### readonly invertClassificationSupported : Boolean
Scene/Scene.js 902

Returns `true` if the `Scene#invertClassification` is supported.

##### See:

- Scene#invertClassification

#### readonly lastRenderTime : JulianDate
Scene/Scene.js 1291

Gets the simulation time when the scene was last rendered. Returns undefined if the scene has not yet been rendered.

#### layers : Layers
Scene/Scene.js 1656

图层管理对象

#### light : Light
Scene/Scene.js 744

The light source for shading. Defaults to a directional light from the Sun.

#### logarithmicDepthBuffer : Boolean
Scene/Scene.js 1543

Whether or not to use a logarithmic depth buffer. Enabling this option will allow for less frustums in the multi-frustum, increasing performance. This property relies on fragmentDepth being supported.

#### logarithmicDepthFarToNearRatio : Number
Scene/Scene.js 388

The far-to-near ratio of the multi-frustum when using a logarithmic depth buffer.

This value is used to create the near and far values for each frustum of the multi-frustum. It is only used when `Scene#logarithmicDepthBuffer` is `true`. When `logarithmicDepthBuffer` is `false`, use `Scene#farToNearRatio`.

Default Value: `1e9`

#### readonly mapMode2D : MapMode2D
Scene/Scene.js 1493

Determines if the 2D map is rotatable or can be scrolled infinitely in the horizontal direction.

#### readonly mapProjection : MapProjection
Scene/Scene.js 1068

Get the map projection to use in 2D and Columbus View modes.

Default Value: `new GeographicProjection()`

#### readonly maximumAliasedLineWidth : Number
Scene/Scene.js 825

The maximum aliased line width, in pixels, supported by this WebGL implementation. It will be at least one.

##### See:

- glGet with `ALIASED_LINE_WIDTH_RANGE`.

#### readonly maximumCubeMapSize : Number
Scene/Scene.js 840

The maximum length in pixels of one edge of a cube map, supported by this WebGL implementation. It will be at least 16.

##### See:

- glGet with `GL_MAX_CUBE_MAP_TEXTURE_SIZE`.

#### maximumRenderTimeChange : Number
Scene/Scene.js 688

If `Scene#requestRenderMode` is `true`, this value defines the maximum change in simulation time allowed before a render is requested. Lower values increase the number of frames rendered and higher values decrease the number of frames rendered. If `undefined`, changes to the simulation time will never request a render. This value impacts the rate of rendering for changes in the scene like lighting, entity property updates, and animations.

Default Value: `0.0`

##### See:

- Improving Performance with Explicit Rendering
- Scene#requestRenderMode

#### minimumDisableDepthTestDistance : Number
Scene/Scene.js 1523

The distance from the camera at which to disable the depth test of billboards, labels and points to, for example, prevent clipping against terrain. When set to zero, the depth test should always be applied. When less than zero, the depth test should never be applied. Setting the disableDepthTestDistance property of a billboard, label or point will override this value.

Default Value: `0.0`

#### mode : SceneMode
Scene/Scene.js 1376

Gets or sets the current mode of the scene.

Default Value: ``SceneMode.SCENE3D``

#### moon : Moon
Scene/Scene.js 339

The `Moon`

Default Value: `undefined`

#### morphComplete : Event
Scene/Scene.js 296

The event fired at the completion of a scene transition.

Default Value: `Event()`

#### morphStart : Event
Scene/Scene.js 289

The event fired at the beginning of a scene transition.

Default Value: `Event()`

#### morphTime : Number
Scene/Scene.js 362

The current morph transition time between 2D/Columbus View and 3D, with 0.0 being 2D or Columbus View and 1.0 being 3D.

Default Value: `1.0`

#### nearToFarDistance2D : Number
Scene/Scene.js 398

Determines the uniform depth size in meters of each frustum of the multifrustum in 2D. If a primitive or model close to the surface shows z-fighting, decreasing this will eliminate the artifact, but decrease performance. On the other hand, increasing this will increase performance but may cause z-fighting among primitives close to the surface.

Default Value: `1.75e6`

#### readonly orderIndependentTranslucency : Boolean
Scene/Scene.js 1352

Gets whether or not the scene has order independent translucency enabled. Note that this only reflects the original construction option, and there are other factors that could prevent OIT from functioning on a given system configuration.

#### readonly pickPositionSupported : Boolean
Scene/Scene.js 855

Returns `true` if the `Scene#pickPosition` function is supported.

##### See:

- Scene#pickPosition

#### pickTranslucentDepth : Boolean
Scene/Scene.js 542

When `true`, enables picking translucent geometry using the depth buffer. Note that `Scene#useDepthPicking` must also be true for enabling this to work.

Render must be called between picks.
There is a decrease in performance when enabled. There are extra draw calls to write depth for translucent geometry.

Default Value: `false`

##### Example:

    // picking the position of a translucent primitive
    viewer.screenSpaceEventHandler.setInputAction(function onLeftClick(movement) {
         var pickedFeature = viewer.scene.pick(movement.position);
         if (!Cesium.defined(pickedFeature)) {
             // nothing picked
             return;
         }
         viewer.scene.render();
         var worldPosition = viewer.scene.pickPosition(movement.position);
    }, Cesium.ScreenSpaceEventType.LEFT_CLICK);

#### postProcessStages : PostProcessStageCollection
Scene/Scene.js 607

Post processing effects applied to the final render.

#### readonly postRender : Event
Scene/Scene.js 1277

Gets the event that will be raised immediately after the scene is rendered. Subscribers to the event receive the Scene instance as the first parameter and the current time as the second parameter.

##### See:

- Improving Performance with Explicit Rendering
- Scene#preUpdate
- Scene#postUpdate
- Scene#postRender

#### readonly postUpdate : Event
Scene/Scene.js 1222

Gets the event that will be raised immediately after the scene is updated and before the scene is rendered. Subscribers to the event receive the Scene instance as the first parameter and the current time as the second parameter.

##### See:

- Improving Performance with Explicit Rendering
- Scene#preUpdate
- Scene#preRender
- Scene#postRender

#### readonly preRender : Event
Scene/Scene.js 1258

Gets the event that will be raised after the scene is updated and immediately before the scene is rendered. Subscribers to the event receive the Scene instance as the first parameter and the current time as the second parameter.

##### See:

- Improving Performance with Explicit Rendering
- Scene#preUpdate
- Scene#postUpdate
- Scene#postRender

#### readonly preUpdate : Event
Scene/Scene.js 1202

Gets the event that will be raised before the scene is updated or rendered. Subscribers to the event receive the Scene instance as the first parameter and the current time as the second parameter.

##### See:

- Improving Performance with Explicit Rendering
- Scene#postUpdate
- Scene#preRender
- Scene#postRender

#### readonly primitives : PrimitiveCollection
Scene/Scene.js 949

Gets the collection of primitives.

#### readonly renderError : Event
Scene/Scene.js 1238

Gets the event that will be raised when an error is thrown inside the `render` function. The Scene instance and the thrown error are the only two parameters passed to the event handler. By default, errors are not rethrown after this event is raised, but that can be changed by setting the `rethrowRenderErrors` property.

#### requestRenderMode : Boolean
Scene/Scene.js 671

When `true`, rendering a frame will only occur when needed as determined by changes within the scene. Enabling improves performance of the application, but requires using `Scene#requestRender` to render a new frame explicitly in this mode. This will be necessary in many cases after making changes to the scene in other parts of the API.

Default Value: `false`

##### See:

- Improving Performance with Explicit Rendering
- Scene#maximumRenderTimeChange
- Scene#requestRender

#### rethrowRenderErrors : Boolean
Scene/Scene.js 273

Exceptions occurring in `render` are always caught in order to raise the `renderError` event. If this property is true, the error is rethrown after the event is raised. If this property is false, the `render` function returns normally after raising the event.

Default Value: `false`

#### readonly sampleHeightSupported : Boolean
Scene/Scene.js 871

Returns `true` if the `Scene#sampleHeight` and `Scene#sampleHeightMostDetailed` functions are supported.

##### See:

- Scene#sampleHeight
- Scene#sampleHeightMostDetailed

#### readonly scene3DOnly : Boolean
Scene/Scene.js 1338

Gets whether or not the scene is optimized for 3D only viewing.

#### readonly screenSpaceCameraController : ScreenSpaceCameraController
Scene/Scene.js 1053

Gets the controller for camera input handling.

#### shadowMap : ShadowMap
Scene/Scene.js 565

The shadow map for the scene's light source. When enabled, models, primitives, and the globe may cast and receive shadows.

#### skyAtmosphere : SkyAtmosphere
Scene/Scene.js 314

The sky atmosphere drawn around the globe.

Default Value: `undefined`

#### skyBox : SkyBox
Scene/Scene.js 306

The `SkyBox` used to draw the stars.

Default Value: `undefined`

##### See:

- Scene#backgroundColor

#### specularEnvironmentMaps : String
Scene/Scene.js 737

The url to the KTX2 file containing the specular environment map and convoluted mipmaps for image-based lighting of PBR models.

#### readonly specularEnvironmentMapsSupported : Boolean
Scene/Scene.js 917

Returns `true` if specular environment maps are supported.

##### See:

- Scene#specularEnvironmentMaps

#### sphericalHarmonicCoefficients : Array.<Cartesian3>
Scene/Scene.js 731

The spherical harmonic coefficients for image-based lighting of PBR models.

#### sun : Sun
Scene/Scene.js 322

The `Sun`.

Default Value: `undefined`

#### sunBloom : Boolean
Scene/Scene.js 330

Uses a bloom filter on the sun when enabled.

Default Value: `true`

#### terrainProvider : TerrainProvider
Scene/Scene.js 1157

The terrain provider providing surface geometry for the globe.

#### readonly terrainProviderChanged : Event
Scene/Scene.js 1179

Gets an event that's raised when the terrain provider is changed

#### useDepthPicking : Boolean
Scene/Scene.js 516

When `true`, enables picking using the depth buffer.

Default Value: `true`

#### useWebVR : Boolean
Scene/Scene.js 1456

When `true`, splits the scene into two viewports with steroscopic views for the left and right eyes. Used for cardboard and WebVR.

Default Value: `false`

#### readonly visualAnalysisManager : VisualAnalysisManager
Scene/Scene.js 961

分析功能管理器

### Methods

#### cartesianToCanvasCoordinates(position, result) → Cartesian2
Scene/Scene.js 4176

Transforms a position in cartesian coordinates to canvas coordinates. This is commonly used to place an HTML element at the same screen position as an object in the scene.

Name | Type | Description
--- | --- | ---
`position` | Cartesian3 | The position in cartesian coordinates.
`result` | Cartesian2 | optional An optional object to return the input position transformed to canvas coordinates.

##### Returns:

The modified result parameter or a new Cartesian2 instance if one was not provided. This may be `undefined` if the input position is near the center of the ellipsoid.

##### Example:

    // Output the canvas position of longitude/latitude (0, 0) every time the mouse moves.
    var scene = widget.scene;
    var ellipsoid = scene.globe.ellipsoid;
    var position = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
    var handler = new Cesium.ScreenSpaceEventHandler(scene.canvas);
    handler.setInputAction(function(movement) {
        console.log(scene.cartesianToCanvasCoordinates(position));
    }, Cesium.ScreenSpaceEventType.MOUSE_MOVE);

#### clampToHeight(cartesian, objectsToExclude, width, result) → Cartesian3
Scene/Scene.js 4091

Clamps the given cartesian position to the scene geometry along the geodetic surface normal. Returns the clamped position or `undefined` if there was no scene geometry to clamp to. May be used to clamp objects to the globe, 3D Tiles, or primitives in the scene.

This function only clamps to globe tiles and 3D Tiles that are rendered in the current view. Clamps to all other primitives regardless of their visibility.

Name | Type | Default | Description
--- | --- | --- | ---
`cartesian` | Cartesian3 |  | The cartesian position.
`objectsToExclude` | Array.<Object> |  | optional A list of primitives, entities, or 3D Tiles features to not clamp to.
`width` | Number | `0.1` | optional Width of the intersection volume in meters.
`result` | Cartesian3 |  | optional An optional object to return the clamped position.

##### Returns:

The modified result parameter or a new Cartesian3 instance if one was not provided. This may be `undefined` if there was no scene geometry to clamp to.

##### Throws:

- DeveloperError : clampToHeight is only supported in 3D mode.
- DeveloperError : clampToHeight requires depth texture support. Check clampToHeightSupported.

##### Example:

    // Clamp an entity to the underlying scene geometry
    var position = entity.position.getValue(Cesium.JulianDate.now());
    entity.position = viewer.scene.clampToHeight(position);

##### See:

- Scene#sampleHeight
- Scene#sampleHeightMostDetailed
- Scene#clampToHeightMostDetailed

#### clampToHeightMostDetailed(cartesians, objectsToExclude, width) → Promise.<Array.<Cartesian3>>
Scene/Scene.js 4154

Initiates an asynchronous `Scene#clampToHeight` query for an array of `Cartesian3` positions using the maximum level of detail for 3D Tilesets in the scene. Returns a promise that is resolved when the query completes. Each position is modified in place. If a position cannot be clamped because no geometry can be sampled at that location, or another error occurs, the element in the array is set to undefined.

Name | Type | Default | Description
--- | --- | --- | ---
`cartesians` | Array.<Cartesian3> |  | The cartesian positions to update with clamped positions.
`objectsToExclude` | Array.<Object> |  | optional A list of primitives, entities, or 3D Tiles features to not clamp to.
`width` | Number | `0.1` | optional Width of the intersection volume in meters.

##### Returns:

A promise that resolves to the provided list of positions when the query has completed.

##### Throws:

- DeveloperError : clampToHeightMostDetailed is only supported in 3D mode.
- DeveloperError : clampToHeightMostDetailed requires depth texture support. Check clampToHeightSupported.

##### Example:

    var cartesians = [
        entities[0].position.getValue(Cesium.JulianDate.now()),
        entities[1].position.getValue(Cesium.JulianDate.now())
    ];
    var promise = viewer.scene.clampToHeightMostDetailed(cartesians);
    promise.then(function(updatedCartesians) {
        entities[0].position = updatedCartesians[0];
        entities[1].position = updatedCartesians[1];
    }

##### See:

- Scene#clampToHeight

#### completeMorph()
Scene/Scene.js 4183

Instantly completes an active transition.

#### destroy()
Scene/Scene.js 4265

Destroys the WebGL resources held by this object. Destroying an object allows for deterministic release of WebGL resources, instead of relying on the garbage collector to destroy this object.
Once an object is destroyed, it should not be used; calling any function other than `isDestroyed` will result in a `DeveloperError` exception. Therefore, assign the return value (`undefined`) to the object as done in the example.

##### Throws:

- DeveloperError : This object was destroyed, i.e., destroy() was called.

##### Example:

    scene = scene && scene.destroy();

##### See:

- Scene#isDestroyed

#### drillPick(windowPosition, limit, width, height) → Array.<*>
Scene/Scene.js 3919

Returns a list of objects, each containing a `primitive` property, for all primitives at a particular window coordinate position. Other properties may also be set depending on the type of primitive and may be used to further identify the picked object. The primitives in the list are ordered by their visual order in the scene (front to back).

Name | Type | Default | Description
--- | --- | --- | ---
`windowPosition` | Cartesian2 |  | Window coordinates to perform picking on.
`limit` | Number |  | optional If supplied, stop drilling after collecting this many picks.
`width` | Number | `3` | optional Width of the pick rectangle.
`height` | Number | `3` | optional Height of the pick rectangle.

##### Returns:

Array of objects, each containing 1 picked primitives.

##### Throws:

- DeveloperError : windowPosition is undefined.

##### Example:

    var pickedObjects = scene.drillPick(new Cesium.Cartesian2(100.0, 200.0));

##### See:

- Scene#pick

#### getCartesian3Position(screePosition, position) → Cartesian3
Scene/Scene.js 4319

根据 场景模式得到拾取坐标

Name | Type | Description
--- | --- | ---
`screePosition` | Cartesian2 | 屏幕坐标
`position` | Cartesian3 | 返回的世界坐标

##### Returns:

返回的世界坐标 (注意检查返回值是否为undefined 因为拾取在天空背景上是undefined)

Author:
  - hys

#### getCompressedTextureFormatSupported(format) → boolean
Scene/Scene.js 1668

Determines if a compressed texture format is supported.

Name | Type | Description
--- | --- | ---
`format` | String | The texture format. May be the name of the format or the WebGL extension name, e.g. s3tc or WEBGL_compressed_texture_s3tc.

##### Returns:

Whether or not the format is supported.

#### isDestroyed() → Boolean
Scene/Scene.js 4245

Returns true if this object was destroyed; otherwise, false.
If this object was destroyed, it should not be used; calling any function other than `isDestroyed` will result in a `DeveloperError` exception.

##### Returns:

`true` if this object was destroyed; otherwise, `false`.

##### See:

- Scene#destroy

#### morphTo2D(duration)
Scene/Scene.js 4191

Asynchronously transitions the scene to 2D.

Name | Type | Default | Description
--- | --- | --- | ---
`duration` | Number | `2.0` | optional The amount of time, in seconds, for transition animations to complete.

#### morphTo3D(duration)
Scene/Scene.js 4223

Asynchronously transitions the scene to 3D.

Name | Type | Default | Description
--- | --- | --- | ---
`duration` | Number | `2.0` | optional The amount of time, in seconds, for transition animations to complete.

#### morphToColumbusView(duration)
Scene/Scene.js 4207

Asynchronously transitions the scene to Columbus View.

Name | Type | Default | Description
--- | --- | --- | ---
`duration` | Number | `2.0` | optional The amount of time, in seconds, for transition animations to complete.

#### pick(windowPosition, width, height) → Object
Scene/Scene.js 3655

Returns an object with a `primitive` property that contains the first (top) primitive in the scene at a particular window coordinate or undefined if nothing is at the location. Other properties may potentially be set depending on the type of primitive and may be used to further identify the picked object.

When a feature of a 3D Tiles tileset is picked, `pick` returns a `Cesium3DTileFeature` object.

Name | Type | Default | Description
--- | --- | --- | ---
`windowPosition` | Cartesian2 |  | Window coordinates to perform picking on.
`width` | Number | `3` | optional Width of the pick rectangle.
`height` | Number | `3` | optional Height of the pick rectangle.

##### Returns:

Object containing the picked primitive.

##### Example:

    // On mouse over, color the feature yellow.
    handler.setInputAction(function(movement) {
        var feature = scene.pick(movement.endPosition);
        if (feature instanceof Cesium.Cesium3DTileFeature) {
            feature.color = Cesium.Color.YELLOW;
        }
    }, Cesium.ScreenSpaceEventType.MOUSE_MOVE);

#### pickByRectangle(rectangle) → Array.<Object>
Scene/Scene.js 3691

获取矩形范围

Name | Type | Description
--- | --- | ---
`rectangle` | BoundingRectangle | 矩形范围

##### Returns:

返回对象列表

Author:
  - 韩彦生

#### pickOid(windowPosition, width, height) → Number
Scene/Scene.js 3680

Name | Type | Default | Description
--- | --- | --- | ---
`windowPosition` | Cartesian2 |  | Window coordinates to perform picking on.
`width` | Number | `3` | optional Width of the pick rectangle.
`height` | Number | `3` | optional Height of the pick rectangle.

##### Returns:

OId值

Author:
  - 冯桂英

#### pickPosition(windowPosition, result) → Cartesian3
Scene/Scene.js 3896

Returns the cartesian position reconstructed from the depth buffer and window position.

The position reconstructed from the depth buffer in 2D may be slightly different from those reconstructed in 3D and Columbus view. This is caused by the difference in the distribution of depth values of perspective and orthographic projection.

Set `Scene#pickTranslucentDepth` to `true` to include the depth of translucent primitives; otherwise, this essentially picks through translucent primitives.

Name | Type | Description
--- | --- | ---
`windowPosition` | Cartesian2 | Window coordinates to perform picking on.
`result` | Cartesian3 | optional The object on which to restore the result.

##### Returns:

The cartesian position.

##### Throws:

- DeveloperError : Picking from the depth buffer is not supported. Check pickPositionSupported.

#### pickTextureCoordinate(windowPosition, width, height) → Color
Scene/Scene.js 3666

Name | Type | Default | Description
--- | --- | --- | ---
`windowPosition` | Cartesian2 |  | Window coordinates to perform picking on.
`width` | Number | `3` | optional Width of the pick rectangle.
`height` | Number | `3` | optional Height of the pick rectangle.

##### Returns:

color RGB form framBuffer

Author:
  - 冯桂英

#### render(time)
Scene/Scene.js 3528

Update and render the scene. It is usually not necessary to call this function directly because `CesiumWidget` or `Viewer` do it automatically.

Name | Type | Description
--- | --- | ---
`time` | JulianDate | optional The simulation time at which to render.

#### requestRender()
Scene/Scene.js 3622

Requests a new rendered frame when `Scene#requestRenderMode` is set to `true`. The render rate will not exceed the `CesiumWidget#targetFrameRate`.

##### See:

- Scene#requestRenderMode

#### sampleHeight(position, objectsToExclude, width) → Number
Scene/Scene.js 4060

Returns the height of scene geometry at the given cartographic position or `undefined` if there was no scene geometry to sample height from. The height of the input position is ignored. May be used to clamp objects to the globe, 3D Tiles, or primitives in the scene.

This function only samples height from globe tiles and 3D Tiles that are rendered in the current view. Samples height from all other primitives regardless of their visibility.

Name | Type | Default | Description
--- | --- | --- | ---
`position` | Cartographic |  | The cartographic position to sample height from.
`objectsToExclude` | Array.<Object> |  | optional A list of primitives, entities, or 3D Tiles features to not sample height from.
`width` | Number | `0.1` | optional Width of the intersection volume in meters.

##### Returns:

The height. This may be `undefined` if there was no scene geometry to sample height from.

##### Throws:

- DeveloperError : sampleHeight is only supported in 3D mode.
- DeveloperError : sampleHeight requires depth texture support. Check sampleHeightSupported.

##### Example:

    var position = new Cesium.Cartographic(-1.31968, 0.698874);
    var height = viewer.scene.sampleHeight(position);
    console.log(height);

##### See:

- Scene#clampToHeight
- Scene#clampToHeightMostDetailed
- Scene#sampleHeightMostDetailed

#### sampleHeightMostDetailed(positions, objectsToExclude, width) → Promise.<Array.<Cartographic>>
Scene/Scene.js 4123

Initiates an asynchronous `Scene#sampleHeight` query for an array of `Cartographic` positions using the maximum level of detail for 3D Tilesets in the scene. The height of the input positions is ignored. Returns a promise that is resolved when the query completes. Each point height is modified in place. If a height cannot be determined because no geometry can be sampled at that location, or another error occurs, the height is set to undefined.

Name | Type | Default | Description
--- | --- | --- | ---
`positions` | Array.<Cartographic> |  | The cartographic positions to update with sampled heights.
`objectsToExclude` | Array.<Object> |  | optional A list of primitives, entities, or 3D Tiles features to not sample height from.
`width` | Number | `0.1` | optional Width of the intersection volume in meters.

##### Returns:

A promise that resolves to the provided list of positions when the query has completed.

##### Throws:

- DeveloperError : sampleHeightMostDetailed is only supported in 3D mode.
- DeveloperError : sampleHeightMostDetailed requires depth texture support. Check sampleHeightSupported.

##### Example:

    var positions = [
        new Cesium.Cartographic(-1.31968, 0.69887),
        new Cesium.Cartographic(-1.10489, 0.83923)
    ];
    var promise = viewer.scene.sampleHeightMostDetailed(positions);
    promise.then(function(updatedPosition) {
        // positions[0].height and positions[1].height have been updated.
        // updatedPositions is just a reference to positions.
    }

##### See:

- Scene#sampleHeight

#### startCustomDisplay(layerList, idList, options)
Scene/Scene.js 4372

设置单体要素高亮

Name | Type | Description
--- | --- | ---
`layerList` | Array.<MapGISM3DSet> | 图层列表
`idList` | Array.<Number> | id列表
`options` | Object | 扩展属性
Name | Type | Default | Description
--- | --- | --- | ---
`color` | Color | `new Cesium.Color(1.0, 0, 0, 0.5)` | optional 高亮颜色
`colorBlendMode` | Cesium3DTileColorBlendMode | `Cesium.Cesium3DTileColorBlendMode.HIGHLIGHT` | optional 高亮模式
`colorBlendAmount` | Number | `0.5` | optional 混合系数
`applyForLayer` | Boolean | `false` | optional 是否应用至图层
`negate` | Color | `true` | optional 是否取反 ——意思是除了id列表中的要素应用color
`negateColor` | Color | `new Cesium.Color.WHITE` | optional 取反的颜色,只有在negate=true 的时候才起作用
`style` | String | `'Edge'` | optional 高亮模式,'Edge':描边;'EdgeHighlight':高亮+描边
`edgeColor` | Color | `new Cesium.Color(0, 0, 1, 1.0)` | optional 描边颜色 默认红色
`isReset` | Boolean | `true` | optional 重置单体数据的颜色

#### stopCustomDisplay(图层列表)
Scene/Scene.js 4455

停止全部高亮

Name | Type | Description
--- | --- | ---
`图层列表` | Array.<MapGISM3DSet> |

#### stopCustomDisplayByIds(layerList, idList)
Scene/Scene.js 4480

根据id停止高亮

Name | Type | Description
--- | --- | ---
`layerList` | Array.<MapGISM3DSet> | 图层列表
`idList` | Array.<Number> | id列表