Class: MapGISTileAvailability

Methods

addAvailableTileRange(level, startX, startY, endX, endY)

engineExtensions/core/MapGISTileAvailability.js, line 27

Marks a rectangular range of tiles in a particular level as being available. For best performance, add your ranges in order of increasing level.

Name	Type	Description
level	Number	The level.
startX	Number	The X coordinate of the first available tiles at the level.
startY	Number	The Y coordinate of the first available tiles at the level.
endX	Number	The X coordinate of the last available tiles at the level.
endY	Number	The Y coordinate of the last available tiles at the level.

computeBestAvailableLevelOverRectangle(rectangle){Number}

engineExtensions/core/MapGISTileAvailability.js, line 77

Finds the most detailed level that is available everywhere within a given rectangle. More detailed tiles may be available in parts of the rectangle, but not the whole thing. The return value of this function may be safely passed to Cesium.sampleTerrain for any position within the rectangle. This function usually completes in time logarithmic to the number of rectangles added with zondy.cesium.MapGISTileAvailability.addAvailableTileRange()

Name	Type	Description
rectangle	Cesium.Rectangle	The rectangle.

Returns:

Type	Description
Number	The best available level for the entire rectangle.

computeChildMaskForTile(level, x, y){Number}

engineExtensions/core/MapGISTileAvailability.js, line 126

Computes a bit mask indicating which of a tile's four children exist. If a child's bit is set, a tile is available for that child. If it is cleared, the tile is not available. The bit values are as follows:

Bit Position	Bit Value	Child Tile
0	1	Southwest
1	2	Southeast
2	4	Northwest
3	8	Northeast

Name	Type	Description
level	Number	The level of the parent tile.
x	Number	The X coordinate of the parent tile.
y	Number	The Y coordinate of the parent tile.

Returns:

Type	Description
Number	The bit mask indicating child availability.

computeMaximumLevelAtPosition(position){Number}

engineExtensions/core/MapGISTileAvailability.js, line 55

Determines the level of the most detailed tile covering the position. This function usually completes in time logarithmic to the number of rectangles added with zondy.cesium.MapGISTileAvailability.addAvailableTileRange()

Name	Type	Description
position	Cesium.Cartographic	The position for which to determine the maximum available level. The height component is ignored.

Throws:

If position is outside any tile according to the tiling scheme.

Type

Cesium.DeveloperError

Returns:

Type	Description
Number	The level of the most detailed tile covering the position.

isTileAvailable(level, x, y){Boolean}

engineExtensions/core/MapGISTileAvailability.js, line 99

Determines if a particular tile is available.

Name	Type	Description
level	Number	The tile level to check.
x	Number	The X coordinate of the tile to check.
y	Number	The Y coordinate of the tile to check.

Returns:

Type	Description
Boolean	True if the tile is available; otherwise, false.