Cesium3DTileset

new Cesium.Cesium3DTileset(options)

A 3D Tiles tileset, used for streaming massive heterogeneous 3D geospatial datasets.
Name Type Description
options Object Object with the following properties:
Name Type Default Description
url Resource | String | Promise.<Resource> | Promise.<String> The url to a tileset JSON file.
show Boolean true optional Determines if the tileset will be shown.
modelMatrix Matrix4 Matrix4.IDENTITY optional A 4x4 transformation matrix that transforms the tileset's root tile.
shadows ShadowMode ShadowMode.ENABLED optional Determines whether the tileset casts or receives shadows from each light source.
maximumScreenSpaceError Number 16 optional The maximum screen space error used to drive level of detail refinement.
maximumMemoryUsage Number 512 optional The maximum amount of memory in MB that can be used by the tileset.
cullWithChildrenBounds Boolean true optional Optimization option. Whether to cull tiles using the union of their children bounding volumes.
dynamicScreenSpaceError Boolean false optional Optimization option. Reduce the screen space error for tiles that are further away from the camera.
dynamicScreenSpaceErrorDensity Number 0.00278 optional Density used to adjust the dynamic screen space error, similar to fog density.
dynamicScreenSpaceErrorFactor Number 4.0 optional A factor used to increase the computed dynamic screen space error.
dynamicScreenSpaceErrorHeightFalloff Number 0.25 optional A ratio of the tileset's height at which the density starts to falloff.
skipLevelOfDetail Boolean true optional Optimization option. Determines if level of detail skipping should be applied during the traversal.
baseScreenSpaceError Number 1024 optional When skipLevelOfDetail is true, the screen space error that must be reached before skipping levels of detail.
skipScreenSpaceErrorFactor Number 16 optional When skipLevelOfDetail is true, a multiplier defining the minimum screen space error to skip. Used in conjunction with skipLevels to determine which tiles to load.
skipLevels Number 1 optional When skipLevelOfDetail is true, a constant defining the minimum number of levels to skip when loading tiles. When it is 0, no levels are skipped. Used in conjunction with skipScreenSpaceErrorFactor to determine which tiles to load.
immediatelyLoadDesiredLevelOfDetail Boolean false optional When skipLevelOfDetail is true, only tiles that meet the maximum screen space error will ever be downloaded. Skipping factors are ignored and just the desired tiles are loaded.
loadSiblings Boolean false optional When skipLevelOfDetail is true, determines whether siblings of visible tiles are always downloaded during traversal.
clippingPlanes ClippingPlaneCollection optional The ClippingPlaneCollection used to selectively disable rendering the tileset.
classificationType ClassificationType optional Determines whether terrain, 3D Tiles or both will be classified by this tileset. See Cesium3DTileset#classificationType for details about restrictions and limitations.
ellipsoid Ellipsoid Ellipsoid.WGS84 optional The ellipsoid determining the size and shape of the globe.
debugFreezeFrame Boolean false optional For debugging only. Determines if only the tiles from last frame should be used for rendering.
debugColorizeTiles Boolean false optional For debugging only. When true, assigns a random color to each tile.
debugWireframe Boolean false optional For debugging only. When true, render's each tile's content as a wireframe.
debugShowBoundingVolume Boolean false optional For debugging only. When true, renders the bounding volume for each tile.
debugShowContentBoundingVolume Boolean false optional For debugging only. When true, renders the bounding volume for each tile's content.
debugShowViewerRequestVolume Boolean false optional For debugging only. When true, renders the viewer request volume for each tile.
debugShowGeometricError Boolean false optional For debugging only. When true, draws labels to indicate the geometric error of each tile.
debugShowRenderingStatistics Boolean false optional For debugging only. When true, draws labels to indicate the number of commands, points, triangles and features for each tile.
debugShowMemoryUsage Boolean false optional For debugging only. When true, draws labels to indicate the texture and geometry memory in megabytes used by each tile.
debugShowUrl Boolean false optional For debugging only. When true, draws labels to indicate the url of each tile.
pointCloudShading Object optional Options for constructing a PointCloudShading object to control point attenuation based on geometric error and lighting.
Throws:
Examples:
var tileset = scene.primitives.add(new Cesium.Cesium3DTileset({
     url : 'http://localhost:8002/tilesets/Seattle/tileset.json'
}));
// Common setting for the skipLevelOfDetail optimization
var tileset = scene.primitives.add(new Cesium.Cesium3DTileset({
     url : 'http://localhost:8002/tilesets/Seattle/tileset.json',
     skipLevelOfDetail : true,
     baseScreenSpaceError : 1024,
     skipScreenSpaceErrorFactor : 16,
     skipLevels : 1,
     immediatelyLoadDesiredLevelOfDetail : false,
     loadSiblings : false,
     cullWithChildrenBounds : true
}));
// Common settings for the dynamicScreenSpaceError optimization
var tileset = scene.primitives.add(new Cesium.Cesium3DTileset({
     url : 'http://localhost:8002/tilesets/Seattle/tileset.json',
     dynamicScreenSpaceError : true,
     dynamicScreenSpaceErrorDensity : 0.00278,
     dynamicScreenSpaceErrorFactor : 4.0,
     dynamicScreenSpaceErrorHeightFalloff : 0.25
}));
See:

Members

The event fired to indicate that all tiles that meet the screen space error this frame are loaded. The tileset is completely loaded for this view.

This event is fired at the end of the frame after the scene is rendered.

Default Value: new Event()
Example:
tileset.allTilesLoaded.addEventListener(function() {
    console.log('All tiles are loaded');
});
See:

readonlyasset : Object

Gets the tileset's asset object property, which contains metadata about the tileset.

See the asset schema in the 3D Tiles spec for the full set of properties.

readonlybasePath : String

The base path that non-absolute paths in tileset JSON file are relative to.
Deprecated: true

baseScreenSpaceError : Number

The screen space error that must be reached before skipping levels of detail.

Only used when Cesium3DTileset#skipLevelOfDetail is true.

Default Value: 1024
The tileset's bounding sphere.
Example:
var tileset = viewer.scene.primitives.add(new Cesium.Cesium3DTileset({
    url : 'http://localhost:8002/tilesets/Seattle/tileset.json'
}));

tileset.readyPromise.then(function(tileset) {
    // Set the camera to view the newly added tileset
    viewer.camera.viewBoundingSphere(tileset.boundingSphere, new Cesium.HeadingPitchRange(0, -0.5, 0));
});

readonlyclassificationType : ClassificationType

Determines whether terrain, 3D Tiles or both will be classified by this tileset.

This option is only applied to tilesets containing batched 3D models, geometry data, or vector data. Even when undefined, vector data and geometry data must render as classifications and will default to rendering on both terrain and other 3D Tiles tilesets.

When enabled for batched 3D model tilesets, there are a few requirements/limitations on the glTF:

  • POSITION and _BATCHID semantics are required.
  • All indices with the same batch id must occupy contiguous sections of the index buffer.
  • All shaders and techniques are ignored. The generated shader simply multiplies the position by the model-view-projection matrix.
  • The only supported extensions are CESIUM_RTC and WEB3D_quantized_attributes.
  • Only one node is supported.
  • Only one mesh per node is supported.
  • Only one primitive per mesh is supported.

Default Value: undefined
Experimental

This feature is using part of the 3D Tiles spec that is not final and is subject to change without Cesium's standard deprecation policy.

The ClippingPlaneCollection used to selectively disable rendering the tileset.

colorBlendAmount : Number

Defines the value used to linearly interpolate between the source color and feature color when the Cesium3DTileset#colorBlendMode is MIX. A value of 0.0 results in the source color while a value of 1.0 results in the feature color, with any value in-between resulting in a mix of the source color and feature color.
Default Value: 0.5
Defines how per-feature colors set from the Cesium API or declarative styling blend with the source colors from the original feature, e.g. glTF material or per-point color in the tile.
Default Value: Cesium3DTileColorBlendMode.HIGHLIGHT

debugColorizeTiles : Boolean

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

When true, assigns a random color to each tile. This is useful for visualizing what features belong to what tiles, especially with additive refinement where features from parent tiles may be interleaved with features from child tiles.

Default Value: false

debugFreezeFrame : Boolean

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

Determines if only the tiles from last frame should be used for rendering. This effectively "freezes" the tileset to the previous frame so it is possible to zoom out and see what was rendered.

Default Value: false

debugShowBoundingVolume : Boolean

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

When true, renders the bounding volume for each visible tile. The bounding volume is white if the tile has a content bounding volume; otherwise, it is red. Tiles that don't meet the screen space error and are still refining to their descendants are yellow.

Default Value: false

debugShowContentBoundingVolume : Boolean

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

When true, renders the bounding volume for each visible tile's content. The bounding volume is blue if the tile has a content bounding volume; otherwise it is red.

Default Value: false

debugShowGeometricError : Boolean

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

When true, draws labels to indicate the geometric error of each tile.

Default Value: false

debugShowMemoryUsage : Boolean

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

When true, draws labels to indicate the geometry and texture memory usage of each tile.

Default Value: false

debugShowRenderingStatistics : Boolean

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

When true, draws labels to indicate the number of commands, points, triangles and features of each tile.

Default Value: false

debugShowUrl : Boolean

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

When true, draws labels to indicate the url of each tile.

Default Value: false

debugShowViewerRequestVolume : Boolean

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

When true, renders the viewer request volume for each tile.

Default Value: false

debugWireframe : Boolean

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

When true, renders each tile's content as a wireframe.

Default Value: false

dynamicScreenSpaceError : Boolean

Optimization option. Whether the tileset should refine based on a dynamic screen space error. Tiles that are further away will be rendered with lower detail than closer tiles. This improves performance by rendering fewer tiles and making less requests, but may result in a slight drop in visual quality for tiles in the distance. The algorithm is biased towards "street views" where the camera is close to the ground plane of the tileset and looking at the horizon. In addition results are more accurate for tightly fitting bounding volumes like box and region.
Default Value: false

dynamicScreenSpaceErrorDensity : Number

A scalar that determines the density used to adjust the dynamic screen space error, similar to Fog. Increasing this value has the effect of increasing the maximum screen space error for all tiles, but in a non-linear fashion. The error starts at 0.0 and increases exponentially until a midpoint is reached, and then approaches 1.0 asymptotically. This has the effect of keeping high detail in the closer tiles and lower detail in the further tiles, with all tiles beyond a certain distance all roughly having an error of 1.0.

The dynamic error is in the range [0.0, 1.0) and is multiplied by dynamicScreenSpaceErrorFactor to produce the final dynamic error. This dynamic error is then subtracted from the tile's actual screen space error.

Increasing dynamicScreenSpaceErrorDensity has the effect of moving the error midpoint closer to the camera. It is analogous to moving fog closer to the camera.

Default Value: 0.00278

dynamicScreenSpaceErrorFactor : Number

A factor used to increase the screen space error of tiles for dynamic screen space error. As this value increases less tiles are requested for rendering and tiles in the distance will have lower detail. If set to zero, the feature will be disabled.
Default Value: 4.0

dynamicScreenSpaceErrorHeightFalloff : Number

A ratio of the tileset's height at which the density starts to falloff. If the camera is below this height the full computed density is applied, otherwise the density falls off. This has the effect of higher density at street level views.

Valid values are between 0.0 and 1.0.

Default Value: 0.25
Gets an ellipsoid describing the shape of the globe.

immediatelyLoadDesiredLevelOfDetail : Boolean

When true, only tiles that meet the maximum screen space error will ever be downloaded. Skipping factors are ignored and just the desired tiles are loaded.

Only used when Cesium3DTileset#skipLevelOfDetail is true.

Default Value: false
The event fired to indicate progress of loading new tiles. This event is fired when a new tile is requested, when a requested tile is finished downloading, and when a downloaded tile has been processed and is ready to render.

The number of pending tile requests, numberOfPendingRequests, and number of tiles processing, numberOfTilesProcessing are passed to the event listener.

This event is fired at the end of the frame after the scene is rendered.

Default Value: new Event()
Example:
tileset.loadProgress.addEventListener(function(numberOfPendingRequests, numberOfTilesProcessing) {
    if ((numberOfPendingRequests === 0) && (numberOfTilesProcessing === 0)) {
        console.log('Stopped loading');
        return;
    }

    console.log('Loading: requests: ' + numberOfPendingRequests + ', processing: ' + numberOfTilesProcessing);
});

loadSiblings : Boolean

Determines whether siblings of visible tiles are always downloaded during traversal. This may be useful for ensuring that tiles are already available when the viewer turns left/right.

Only used when Cesium3DTileset#skipLevelOfDetail is true.

Default Value: false

maximumMemoryUsage : Number

The maximum amount of GPU memory (in MB) that may be used to cache tiles. This value is estimated from geometry, textures, and batch table textures of loaded tiles. For point clouds, this value also includes per-point metadata.

Tiles not in view are unloaded to enforce this.

If decreasing this value results in unloading tiles, the tiles are unloaded the next frame.

If tiles sized more than maximumMemoryUsage are needed to meet the desired screen space error, determined by Cesium3DTileset#maximumScreenSpaceError, for the current view, then the memory usage of the tiles loaded will exceed maximumMemoryUsage. For example, if the maximum is 256 MB, but 300 MB of tiles are needed to meet the screen space error, then 300 MB of tiles may be loaded. When these tiles go out of view, they will be unloaded.

Default Value: 512
See:

maximumScreenSpaceError : Number

The maximum screen space error used to drive level of detail refinement. This value helps determine when a tile refines to its descendants, and therefore plays a major role in balancing performance with visual quality.

A tile's screen space error is roughly equivalent to the number of pixels wide that would be drawn if a sphere with a radius equal to the tile's geometric error were rendered at the tile's position. If this value exceeds maximumScreenSpaceError the tile refines to its descendants.

Depending on the tileset, maximumScreenSpaceError may need to be tweaked to achieve the right balance. Higher values provide better performance but lower visual quality.

Default Value: 16
A 4x4 transformation matrix that transforms the entire tileset.
Default Value: Matrix4.IDENTITY
Example:
// Adjust a tileset's height from the globe's surface.
var heightOffset = 20.0;
var boundingSphere = tileset.boundingSphere;
var cartographic = Cesium.Cartographic.fromCartesian(boundingSphere.center);
var surface = Cesium.Cartesian3.fromRadians(cartographic.longitude, cartographic.latitude, 0.0);
var offset = Cesium.Cartesian3.fromRadians(cartographic.longitude, cartographic.latitude, heightOffset);
var translation = Cesium.Cartesian3.subtract(offset, surface, new Cesium.Cartesian3());
tileset.modelMatrix = Cesium.Matrix4.fromTranslation(translation);
Options for controlling point size based on geometric error and eye dome lighting.

readonlyproperties : Object

Gets the tileset's properties dictionary object, which contains metadata about per-feature properties.

See the properties schema in the 3D Tiles spec for the full set of properties.

Example:
console.log('Maximum building height: ' + tileset.properties.height.maximum);
console.log('Minimum building height: ' + tileset.properties.height.minimum);
See:

readonlyready : Boolean

When true, the tileset's root tile is loaded and the tileset is ready to render. This is set to true right before Cesium3DTileset#readyPromise is resolved.
Default Value: false

readonlyreadyPromise : Promise.<Cesium3DTileset>

Gets the promise that will be resolved when the tileset's root tile is loaded and the tileset is ready to render.

This promise is resolved at the end of the frame before the first frame the tileset is rendered in.

Example:
tileset.readyPromise.then(function(tileset) {
    // tile.properties is not defined until readyPromise resolves.
    var properties = tileset.properties;
    if (Cesium.defined(properties)) {
        for (var name in properties) {
            console.log(properties[name]);
        }
    }
});
Determines whether the tileset casts or receives shadows from each light source.

Enabling shadows has a performance impact. A tileset that casts shadows must be rendered twice, once from the camera and again from the light's point of view.

Shadows are rendered only when Viewer#shadows is true.

Default Value: ShadowMode.ENABLED
Determines if the tileset will be shown.
Default Value: true

skipLevelOfDetail : Boolean

Optimization option. Determines if level of detail skipping should be applied during the traversal.

The common strategy for replacement-refinement traversal is to store all levels of the tree in memory and require all children to be loaded before the parent can refine. With this optimization levels of the tree can be skipped entirely and children can be rendered alongside their parents. The tileset requires significantly less memory when using this optimization.

Default Value: true

skipLevels : Number

Constant defining the minimum number of levels to skip when loading tiles. When it is 0, no levels are skipped. For example, if a tile is level 1, no tiles will be loaded unless they are at level greater than 2.

Only used when Cesium3DTileset#skipLevelOfDetail is true.

Default Value: 1

skipScreenSpaceErrorFactor : Number

Multiplier defining the minimum screen space error to skip. For example, if a tile has screen space error of 100, no tiles will be loaded unless they are leaves or have a screen space error <= 100 / skipScreenSpaceErrorFactor.

Only used when Cesium3DTileset#skipLevelOfDetail is true.

Default Value: 16
The style, defined using the 3D Tiles Styling language, applied to each feature in the tileset.

Assign undefined to remove the style, which will restore the visual appearance of the tileset to its default when no style was applied.

The style is applied to a tile before the Cesium3DTileset#tileVisible event is raised, so code in tileVisible can manually set a feature's properties (e.g. color and show) after the style is applied. When a new style is assigned any manually set properties are overwritten.

Default Value: undefined
Example:
tileset.style = new Cesium.Cesium3DTileStyle({
   color : {
       conditions : [
           ['${Height} >= 100', 'color("purple", 0.5)'],
           ['${Height} >= 50', 'color("red")'],
           ['true', 'color("blue")']
       ]
   },
   show : '${Height} > 0',
   meta : {
       description : '"Building id ${id} has height ${Height}."'
   }
});
See:
The event fired to indicate that a tile's content failed to load.

If there are no event listeners, error messages will be logged to the console.

Default Value: new Event()
Example:
tileset.tileFailed.addEventListener(function(error) {
    console.log('An error occurred loading tile: ' + error.url);
    console.log('Error: ' + error.message);
});
The event fired to indicate that a tile's content was loaded.

The loaded Cesium3DTile is passed to the event listener.

This event is fired during the tileset traversal while the frame is being rendered so that updates to the tile take effect in the same frame. Do not create or modify Cesium entities or primitives during the event listener.

Default Value: new Event()
Example:
tileset.tileLoad.addEventListener(function(tile) {
    console.log('A tile was loaded.');
});

readonlytilesLoaded : Boolean

When true, all tiles that meet the screen space error this frame are loaded. The tileset is completely loaded for this view.
Default Value: false
See:
The event fired to indicate that a tile's content was unloaded.

The unloaded Cesium3DTile is passed to the event listener.

This event is fired immediately before the tile's content is unloaded while the frame is being rendered so that the event listener has access to the tile's content. Do not create or modify Cesium entities or primitives during the event listener.

Default Value: new Event()
Example:
tileset.tileUnload.addEventListener(function(tile) {
    console.log('A tile was unloaded from the cache.');
});
See:
This event fires once for each visible tile in a frame. This can be used to manually style a tileset.

The visible Cesium3DTile is passed to the event listener.

This event is fired during the tileset traversal while the frame is being rendered so that updates to the tile take effect in the same frame. Do not create or modify Cesium entities or primitives during the event listener.

Default Value: new Event()
Examples:
tileset.tileVisible.addEventListener(function(tile) {
    if (tile.content instanceof Cesium.Batched3DModel3DTileContent) {
        console.log('A Batched 3D Model tile is visible.');
    }
});
// Apply a red style and then manually set random colors for every other feature when the tile becomes visible.
tileset.style = new Cesium.Cesium3DTileStyle({
    color : 'color("red")'
});
tileset.tileVisible.addEventListener(function(tile) {
    var content = tile.content;
    var featuresLength = content.featuresLength;
    for (var i = 0; i < featuresLength; i+=2) {
        content.getFeature(i).color = Cesium.Color.fromRandom();
    }
});

readonlytimeSinceLoad : Number

Returns the time, in milliseconds, since the tileset was loaded and first updated.

readonlytotalMemoryUsageInBytes : Number

The total amount of GPU memory in bytes used by the tileset. This value is estimated from geometry, texture, and batch table textures of loaded tiles. For point clouds, this value also includes per-point metadata.
See:

readonlyurl : String

The url to a tileset JSON file.

Methods

staticCesium.Cesium3DTileset.loadJson(tilesetUrl)Promise.<Object>

Provides a hook to override the method used to request the tileset json useful when fetching tilesets from remote servers
Name Type Description
tilesetUrl Resource | String The url of the json file to be fetched
Returns:
A promise that resolves with the fetched json data
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:
tileset = tileset && tileset.destroy();
See:

isDestroyed()Boolean

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:
Marks the tileset's Cesium3DTileset#style as dirty, which forces all features to re-evaluate the style in the next frame each is visible.

trimLoadedTiles()

Unloads all tiles that weren't selected the previous frame. This can be used to explicitly manage the tile cache and reduce the total number of tiles loaded below Cesium3DTileset#maximumMemoryUsage.

Tile unloads occur at the next frame to keep all the WebGL delete calls within the render loop.

Called when Viewer or CesiumWidget render the scene to get the draw commands needed to render this primitive.

Do not call this function directly. This is documented just to list the exceptions that may be propagated when the scene is rendered: