Provides terrain or other geometry for the surface of an ellipsoid. The surface geometry is
organized into a pyramid of tiles according to a
TilingScheme
. This type describes an
interface and is not intended to be instantiated directly.
Members
Specifies the quality of terrain created from heightmaps. A value of 1.0 will
ensure that adjacent heightmap vertices are separated by no more than
Globe.maximumScreenSpaceError
screen pixels and will probably go very slowly.
A value of 0.5 will cut the estimated level zero geometric error in half, allowing twice the
screen pixels between adjacent heightmap vertices and thus rendering more quickly.
readonly availability : TileAvailability
Gets an object that can be used to determine availability of terrain from this provider, such as
at points and in rectangles. This property may be undefined if availability
information is not available.
readonly credit : Credit
Gets the credit to display when this terrain provider is active. Typically this is used to credit
the source of the terrain.
readonly errorEvent : Event.<TerrainProvider.ErrorEvent>
Gets an event that is raised when the terrain provider encounters an asynchronous error. By subscribing
to the event, you will be notified of the error and can potentially recover from it. Event listeners
are passed an instance of
TileProviderError
.
Gets a value indicating whether or not the requested tiles include vertex normals.
Gets a value indicating whether or not the provider includes a water mask. The water mask
indicates which areas of the globe are water rather than land, so they can be rendered
as a reflective surface with animated waves.
readonly tilingScheme : TilingScheme
Gets the tiling scheme used by the provider.
Methods
static Cesium.TerrainProvider.getEstimatedLevelZeroGeometricErrorForAHeightmap(ellipsoid, tileImageWidth, numberOfTilesAtLevelZero) → number
Determines an appropriate geometric error estimate when the geometry comes from a heightmap.
Name | Type | Description |
---|---|---|
ellipsoid |
Ellipsoid | The ellipsoid to which the terrain is attached. |
tileImageWidth |
number | The width, in pixels, of the heightmap associated with a single tile. |
numberOfTilesAtLevelZero |
number | The number of tiles in the horizontal direction at tile level zero. |
Returns:
An estimated geometric error.
Gets a list of indices for a triangle mesh representing a regular grid. Calling
this function multiple times with the same grid width and height returns the
same list of indices. The total number of vertices must be less than or equal
to 65536.
Name | Type | Description |
---|---|---|
width |
number | The number of vertices in the regular grid in the horizontal direction. |
height |
number | The number of vertices in the regular grid in the vertical direction. |
Returns:
The list of indices. Uint16Array gets returned for 64KB or less and Uint32Array for 4GB or less.
Gets the maximum geometric error allowed in a tile at a given level.
Name | Type | Description |
---|---|---|
level |
number | The tile level for which to get the maximum geometric error. |
Returns:
The maximum geometric error.
Determines whether data for a tile is available to be loaded.
Name | Type | Description |
---|---|---|
x |
number | The X coordinate of the tile for which to request geometry. |
y |
number | The Y coordinate of the tile for which to request geometry. |
level |
number | The level of the tile for which to request geometry. |
Returns:
Undefined if not supported by the terrain provider, otherwise true or false.
Makes sure we load availability data for a tile
Name | Type | Description |
---|---|---|
x |
number | The X coordinate of the tile for which to request geometry. |
y |
number | The Y coordinate of the tile for which to request geometry. |
level |
number | The level of the tile for which to request geometry. |
Returns:
Undefined if nothing need to be loaded or a Promise that resolves when all required tiles are loaded
requestTileGeometry(x, y, level, request) → Promise.<TerrainData>|undefined
Requests the geometry for a given tile. The result must include terrain data and
may optionally include a water mask and an indication of which child tiles are available.
Name | Type | Description |
---|---|---|
x |
number | The X coordinate of the tile for which to request geometry. |
y |
number | The Y coordinate of the tile for which to request geometry. |
level |
number | The level of the tile for which to request geometry. |
request |
Request | optional The request object. Intended for internal use only. |
Returns:
A promise for the requested geometry. If this method
returns undefined instead of a promise, it is an indication that too many requests are already
pending and the request will be retried later.
Type Definitions
A function that is called when an error occurs.
This:
Name | Type | Description |
---|---|---|
err |
TileProviderError | An object holding details about the error that occurred. |