TerrainProvider

new TerrainProvider()

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.
See:

Members

staticTerrainProvider.heightmapTerrainQuality

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.

credit :Credit

Gets the credit to display when this terrain provider is active. Typically this is used to credit the source of the terrain. This function should not be called before TerrainProvider#ready returns true.

errorEvent :Event

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.

hasVertexNormals :Boolean

Gets a value indicating whether or not the requested tiles include vertex normals. This function should not be called before TerrainProvider#ready returns true.

hasWaterMask :Boolean

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. This function should not be called before TerrainProvider#ready returns true.

ready :Boolean

Gets a value indicating whether or not the provider is ready for use.

tilingScheme :TilingScheme

Gets the tiling scheme used by the provider. This function should not be called before TerrainProvider#ready returns true.

Methods

staticTerrainProvider.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.

staticTerrainProvider.getRegularGridIndices(width, height)Uint16Array

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.

getLevelMaximumGeometricError(level)Number

Gets the maximum geometric error allowed in a tile at a given level. This function should not be called before TerrainProvider#ready returns true.
Name Type Description
level Number The tile level for which to get the maximum geometric error.
Returns:
The maximum geometric error.

getTileDataAvailable(x, y, level)Boolean

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.

requestTileGeometry(x, y, level, throttleRequests)Promise|TerrainData

Requests the geometry for a given tile. This function should not be called before TerrainProvider#ready returns true. The result must include terrain data and may optionally include a water mask and an indication of which child tiles are available.
Name Type Default 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.
throttleRequests Boolean true optional True if the number of simultaneous requests should be limited, or false if the request should be initiated regardless of the number of requests already in progress.
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.