Viewer

new Cesium.Viewer(container, options)

A base widget for building applications. It composites all of the standard Cesium widgets into one reusable package. The widget can always be extended by using mixins, which add functionality useful for a variety of applications.
Name Type Description
container Element | String The DOM element or ID that will contain the widget.
options Viewer.ConstructorOptions optional Object describing initialization options
Throws:
  • DeveloperError : Element with id "container" does not exist in the document.
  • DeveloperError : options.selectedImageryProviderViewModel is not available when not using the BaseLayerPicker widget, specify options.imageryProvider instead.
  • DeveloperError : options.selectedTerrainProviderViewModel is not available when not using the BaseLayerPicker widget, specify options.terrainProvider instead.
Example:
//Initialize the viewer widget with several custom options and mixins.
const viewer = new Cesium.Viewer('cesiumContainer', {
    //Start in Columbus Viewer
    sceneMode : Cesium.SceneMode.COLUMBUS_VIEW,
    //Use Cesium World Terrain
    terrainProvider : Cesium.createWorldTerrain(),
    //Hide the base layer picker
    baseLayerPicker : false,
    //Use OpenStreetMaps
    imageryProvider : new Cesium.OpenStreetMapImageryProvider({
        url : 'https://a.tile.openstreetmap.org/'
    }),
    skyBox : new Cesium.SkyBox({
        sources : {
          positiveX : 'stars/TychoSkymapII.t3_08192x04096_80_px.jpg',
          negativeX : 'stars/TychoSkymapII.t3_08192x04096_80_mx.jpg',
          positiveY : 'stars/TychoSkymapII.t3_08192x04096_80_py.jpg',
          negativeY : 'stars/TychoSkymapII.t3_08192x04096_80_my.jpg',
          positiveZ : 'stars/TychoSkymapII.t3_08192x04096_80_pz.jpg',
          negativeZ : 'stars/TychoSkymapII.t3_08192x04096_80_mz.jpg'
        }
    }),
    // Show Columbus View map with Web Mercator projection
    mapProjection : new Cesium.WebMercatorProjection()
});

//Add basic drag and drop functionality
viewer.extend(Cesium.viewerDragDropMixin);

//Show a pop-up alert if we encounter an error when processing a dropped file
viewer.dropError.addEventListener(function(dropHandler, name, error) {
    console.log(error);
    window.alert(error);
});
Demo:
See:

Members

allowDataSourcesToSuspendAnimation : Boolean

Gets or sets whether or not data sources can temporarily pause animation in order to avoid showing an incomplete picture to the user. For example, if asynchronous primitives are being processed in the background, the clock will not advance until the geometry is ready.
Gets the Animation widget.
Gets the BaseLayerPicker.

readonly bottomContainer : Element

Gets the DOM element for the area at the bottom of the window containing the CreditDisplay and potentially other things.
Gets the camera.

readonly canvas : HTMLCanvasElement

Gets the canvas.
Gets the CesiumWidget.
Gets the clock.
Gets or sets the data source to track with the viewer's clock.
Gets the clock view model.

readonly container : Element

Gets the parent container.
Gets the display used for DataSource visualization.
Gets the set of DataSource instances to be visualized.
Gets the collection of entities not tied to a particular data source. This is a shortcut to dataSourceDisplay.defaultDataSource.entities.
Gets the FullscreenButton.
Gets the Geocoder.
Gets the HomeButton.
Gets the collection of image layers that will be rendered on the globe.
Gets the info box.
Gets the NavigationHelpButton.
Gets the post-process stages.
Gets the ProjectionPicker.

resolutionScale : Number

Gets or sets a scaling factor for rendering resolution. Values less than 1.0 can improve performance on less powerful devices while values greater than 1.0 will render at a higher resolution and then scale down, resulting in improved visual fidelity. For example, if the widget is laid out at a size of 640x480, setting this value to 0.5 will cause the scene to be rendered at 320x240 and then scaled up while setting it to 2.0 will cause the scene to be rendered at 1280x960 and then scaled down.
Default Value: 1.0
Gets the scene.
Gets the SceneModePicker.
Gets the screen space event handler.

selectedEntity : Entity|undefined

Gets or sets the object instance for which to display a selection indicator. If a user interactively picks a Cesium3DTilesFeature instance, then this property will contain a transient Entity instance with a property named "feature" that is the instance that was picked.

readonly selectedEntityChanged : Event

Gets the event that is raised when the selected entity changes.
Gets the selection indicator.
Get the scene's shadow map
Determines if shadows are cast by light sources.

targetFrameRate : Number

Gets or sets the target frame rate of the widget when useDefaultRenderLoop is true. If undefined, the browser's requestAnimationFrame implementation determines the frame rate. If defined, this value must be greater than 0. A value higher than the underlying requestAnimationFrame implementation will have no effect.
The terrain provider providing surface geometry for the globe.
Determines if the terrain casts or shadows from light sources.
Gets the Timeline widget.

trackedEntity : Entity|undefined

Gets or sets the Entity instance currently being tracked by the camera.

readonly trackedEntityChanged : Event

Gets the event that is raised when the tracked entity changes.

useBrowserRecommendedResolution : Boolean

Boolean flag indicating if the browser's recommended resolution is used. If true, the browser's device pixel ratio is ignored and 1.0 is used instead, effectively rendering based on CSS pixels instead of device pixels. This can improve performance on less powerful devices that have high pixel density. When false, rendering will be in device pixels. Viewer#resolutionScale will still take effect whether this flag is true or false.
Default Value: true

useDefaultRenderLoop : Boolean

Gets or sets whether or not this widget should control the render loop. If true the widget will use requestAnimationFrame to perform rendering and resizing of the widget, as well as drive the simulation clock. If set to false, you must manually call the resize, render methods as part of a custom render loop. If an error occurs during rendering, Scene's renderError event will be raised and this property will be set to false. It must be set back to true to continue rendering after the error.
Gets the VRButton.

Methods

Destroys the widget. Should be called if permanently removing the widget from layout.

extend(mixin, options)

Extends the base viewer functionality with the provided mixin. A mixin may add additional properties, functions, or other behavior to the provided viewer instance.
Name Type Description
mixin Viewer.ViewerMixin The Viewer mixin to add to this instance.
options Object optional The options object to be passed to the mixin function.
See:

flyTo(target, options)Promise.<Boolean>

Flies the camera to the provided entity, entities, or data source. If the data source is still in the process of loading or the visualization is otherwise still loading, this method waits for the data to be ready before performing the flight.

The offset is heading/pitch/range in the local east-north-up reference frame centered at the center of the bounding sphere. The heading and the pitch angles are defined in the local east-north-up reference frame. The heading is the angle from y axis and increasing towards the x axis. Pitch is the rotation from the xy-plane. Positive pitch angles are above the plane. Negative pitch angles are below the plane. The range is the distance from the center. If the range is zero, a range will be computed such that the whole bounding sphere is visible.

In 2D, there must be a top down view. The camera will be placed above the target looking down. The height above the target will be the range. The heading will be determined from the offset. If the heading cannot be determined from the offset, the heading will be north.

Name Type Description
target Entity | Array.<Entity> | EntityCollection | DataSource | ImageryLayer | Cesium3DTileset | TimeDynamicPointCloud | Promise.<(Entity|Array.<Entity>|EntityCollection|DataSource|ImageryLayer|Cesium3DTileset|TimeDynamicPointCloud|VoxelPrimitive)> The entity, array of entities, entity collection, data source, Cesium3DTileset, point cloud, or imagery layer to view. You can also pass a promise that resolves to one of the previously mentioned types.
options Object optional Object with the following properties:
Name Type Default Description
duration Number 3.0 optional The duration of the flight in seconds.
maximumHeight Number optional The maximum height at the peak of the flight.
offset HeadingPitchRange optional The offset from the target in the local east-north-up reference frame centered at the target.
Returns:
A Promise that resolves to true if the flight was successful or false if the target is not currently visualized in the scene or the flight was cancelled. //TODO: Cleanup entity mentions
This forces the widget to re-think its layout, including widget sizes and credit placement.

isDestroyed()Boolean

Returns:
true if the object has been destroyed, false otherwise.
Renders the scene. This function is called automatically unless useDefaultRenderLoop is set to false;
Resizes the widget to match the container size. This function is called automatically as needed unless useDefaultRenderLoop is set to false.

zoomTo(target, offset)Promise.<Boolean>

Asynchronously sets the camera to view the provided entity, entities, or data source. If the data source is still in the process of loading or the visualization is otherwise still loading, this method waits for the data to be ready before performing the zoom.

The offset is heading/pitch/range in the local east-north-up reference frame centered at the center of the bounding sphere. The heading and the pitch angles are defined in the local east-north-up reference frame. The heading is the angle from y axis and increasing towards the x axis. Pitch is the rotation from the xy-plane. Positive pitch angles are above the plane. Negative pitch angles are below the plane. The range is the distance from the center. If the range is zero, a range will be computed such that the whole bounding sphere is visible.

In 2D, there must be a top down view. The camera will be placed above the target looking down. The height above the target will be the range. The heading will be determined from the offset. If the heading cannot be determined from the offset, the heading will be north.

Name Type Description
target Entity | Array.<Entity> | EntityCollection | DataSource | ImageryLayer | Cesium3DTileset | TimeDynamicPointCloud | Promise.<(Entity|Array.<Entity>|EntityCollection|DataSource|ImageryLayer|Cesium3DTileset|TimeDynamicPointCloud|VoxelPrimitive)> The entity, array of entities, entity collection, data source, Cesium3DTileset, point cloud, or imagery layer to view. You can also pass a promise that resolves to one of the previously mentioned types.
offset HeadingPitchRange optional The offset from the center of the entity in the local east-north-up reference frame.
Returns:
A Promise that resolves to true if the zoom was successful or false if the target is not currently visualized in the scene or the zoom was cancelled.

Type Definitions

Cesium.Viewer.ConstructorOptions

Initialization options for the Viewer constructor
Properties:
Name Type Attributes Default Description
animation Boolean <optional>
true If set to false, the Animation widget will not be created.
baseLayerPicker Boolean <optional>
true If set to false, the BaseLayerPicker widget will not be created.
fullscreenButton Boolean <optional>
true If set to false, the FullscreenButton widget will not be created.
vrButton Boolean <optional>
false If set to true, the VRButton widget will be created.
geocoder Boolean | Array.<GeocoderService> <optional>
true If set to false, the Geocoder widget will not be created.
homeButton Boolean <optional>
true If set to false, the HomeButton widget will not be created.
infoBox Boolean <optional>
true If set to false, the InfoBox widget will not be created.
sceneModePicker Boolean <optional>
true If set to false, the SceneModePicker widget will not be created.
selectionIndicator Boolean <optional>
true If set to false, the SelectionIndicator widget will not be created.
timeline Boolean <optional>
true If set to false, the Timeline widget will not be created.
navigationHelpButton Boolean <optional>
true If set to false, the navigation help button will not be created.
navigationInstructionsInitiallyVisible Boolean <optional>
true True if the navigation instructions should initially be visible, or false if the should not be shown until the user explicitly clicks the button.
scene3DOnly Boolean <optional>
false When true, each geometry instance will only be rendered in 3D to save GPU memory.
shouldAnimate Boolean <optional>
false true if the clock should attempt to advance simulation time by default, false otherwise. This option takes precedence over setting Viewer#clockViewModel.
clockViewModel ClockViewModel <optional>
new ClockViewModel(clock) The clock view model to use to control current time.
selectedImageryProviderViewModel ProviderViewModel <optional>
The view model for the current base imagery layer, if not supplied the first available base layer is used. This value is only valid if `baseLayerPicker` is set to true.
imageryProviderViewModels Array.<ProviderViewModel> <optional>
createDefaultImageryProviderViewModels() The array of ProviderViewModels to be selectable from the BaseLayerPicker. This value is only valid if `baseLayerPicker` is set to true.
selectedTerrainProviderViewModel ProviderViewModel <optional>
The view model for the current base terrain layer, if not supplied the first available base layer is used. This value is only valid if `baseLayerPicker` is set to true.
terrainProviderViewModels Array.<ProviderViewModel> <optional>
createDefaultTerrainProviderViewModels() The array of ProviderViewModels to be selectable from the BaseLayerPicker. This value is only valid if `baseLayerPicker` is set to true.
imageryProvider ImageryProvider <optional>
createWorldImagery() The imagery provider to use. This value is only valid if `baseLayerPicker` is set to false.
terrainProvider TerrainProvider <optional>
new EllipsoidTerrainProvider() The terrain provider to use
skyBox SkyBox | false <optional>
The skybox used to render the stars. When undefined, the default stars are used. If set to false, no skyBox, Sun, or Moon will be added.
skyAtmosphere SkyAtmosphere | false <optional>
Blue sky, and the glow around the Earth's limb. Set to false to turn it off.
fullscreenElement Element | String <optional>
document.body The element or id to be placed into fullscreen mode when the full screen button is pressed.
useDefaultRenderLoop Boolean <optional>
true True if this widget should control the render loop, false otherwise.
targetFrameRate Number <optional>
The target frame rate when using the default render loop.
showRenderLoopErrors Boolean <optional>
true If true, this widget will automatically display an HTML panel to the user containing the error, if a render loop error occurs.
useBrowserRecommendedResolution Boolean <optional>
true If true, render at the browser's recommended resolution and ignore window.devicePixelRatio.
automaticallyTrackDataSourceClocks Boolean <optional>
true If true, this widget will automatically track the clock settings of newly added DataSources, updating if the DataSource's clock changes. Set this to false if you want to configure the clock independently.
contextOptions ContextOptions <optional>
Context and WebGL creation properties passed to Scene.
sceneMode SceneMode <optional>
SceneMode.SCENE3D The initial scene mode.
mapProjection MapProjection <optional>
new GeographicProjection() The map projection to use in 2D and Columbus View modes.
globe Globe | false <optional>
new Globe(mapProjection.ellipsoid) The globe to use in the scene. If set to false, no globe will be added.
orderIndependentTranslucency Boolean <optional>
true If true and the configuration supports it, use order independent translucency.
creditContainer Element | String <optional>
The DOM element or ID that will contain the CreditDisplay. If not specified, the credits are added to the bottom of the widget itself.
creditViewport Element | String <optional>
The DOM element or ID that will contain the credit pop up created by the CreditDisplay. If not specified, it will appear over the widget itself.
dataSources DataSourceCollection <optional>
new DataSourceCollection() The collection of data sources visualized by the widget. If this parameter is provided, the instance is assumed to be owned by the caller and will not be destroyed when the viewer is destroyed.
shadows Boolean <optional>
false Determines if shadows are cast by light sources.
terrainShadows ShadowMode <optional>
ShadowMode.RECEIVE_ONLY Determines if the terrain casts or receives shadows from light sources.
mapMode2D MapMode2D <optional>
MapMode2D.INFINITE_SCROLL Determines if the 2D map is rotatable or can be scrolled infinitely in the horizontal direction.
projectionPicker Boolean <optional>
false If set to true, the ProjectionPicker widget will be created.
blurActiveElementOnCanvasFocus Boolean <optional>
true If true, the active element will blur when the viewer's canvas is clicked. Setting this to false is useful for cases when the canvas is clicked only for retrieving position or an entity data without actually meaning to set the canvas to be the active element.
requestRenderMode Boolean <optional>
false If true, rendering a frame will only occur when needed as determined by changes within the scene. Enabling reduces the CPU/GPU usage of your application and uses less battery on mobile, 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 <optional>
0.0 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.
depthPlaneEllipsoidOffset Number <optional>
0.0 Adjust the DepthPlane to address rendering artefacts below ellipsoid zero elevation.
msaaSamples Number <optional>
1 If provided, this value controls the rate of multisample antialiasing. Typical multisampling rates are 2, 4, and sometimes 8 samples per pixel. Higher sampling rates of MSAA may impact performance in exchange for improved visual quality. This value only applies to WebGL2 contexts that support multisample render targets.

Cesium.Viewer.ViewerMixin(viewer, options)

A function that augments a Viewer instance with additional functionality.
Name Type Description
viewer Viewer The viewer instance.
options Object Options object to be passed to the mixin function.
See:
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