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ObservationsLayer

Description

The observations layer allows you to track entities as they move around the map. See the Observations Layer docs for more details.

ObservationsLayer

Constructors

new ObservationsLayer(def)

Creates a new instance of the layer.

Parameters

def

object

optional

The layer definition object.

Initial data to load into this layer. Data can be changed after instantiation via layer.data().

id

string

optional

A unique identifier for this layer. If omitted one will be generated automatically.

Initial options to set on this layer. Options can be changed after instantiation via layer.options() or layer.resetOptions().

visible

boolean

optional

Initial visibilty of this layer. Visibilty can be changed after instantiation via layer.visible().

Properties

id

string

readonly

A unique id of the layer.

Methods

data(data)

Gets or sets the current data for this layer.

Parameters

The layer data to be displayed.

A reference to the data object it was most recently passed.

options(options)

Gets or sets the layer options while preserving any previously set options.

Parameters

The layer options to be set.

Returns
object

An object containing all layer options and their current values.

resetOptions(options)

Sets the provided layer options while resetting any other previously set options to default values.

Parameters

The layer options to be set.

Returns
void

visible(state)

Gets or sets the layer visibility.

Parameters

state

boolean

optional

Whether the layer is visible.

Returns
boolean

Observation

Defines the observation of an entity at a specific place and time.

Properties

entityId

string

The id of the observed entity.

latitude

number

The latitude of the observation in degrees. Should be in the range -90 to 90.

longitude

number

The longitude of the observation in degrees. Should be in the range -180 to 180.

time

number | Date

The time of the observation as a Date in local time or a millisecond number in UTC.

type

"observation"

The type of the item.


ObservationsItem

ObservationsItem

An observation or trajectory that can appear in the ObservationsLayer.


ObservationsLayerData

Defines the data to load into the ObservationsLayer.

Properties

entities

Record<string, ObservedEntity>

A dictionary of observed entities, where the keys are the entity ids and the values are ObservedEntity objects.

observations

Record<string, Observation>

A dictionary of observations, where the keys are the observation ids and the values are Observation objects.


ObservationsLayerOptions

Options related to the observations layer.

Properties

autoStyleFadeTime

number

optional

default value

500

Time in milliseconds to change between 'individual' and 'trajectory' when ObservationsLayerStyle is set to 'auto'.

backgroundAlpha

number

optional

default value

0.2

The alpha value to apply to observations that are not within the timeForegroundRange.

individual

object

optional

Options applied when observations are shown individually.

autoRange
object

optional

Defines the range of zoom levels where individual observations are displayed when ObservationsLayerStyle is set to 'auto'.

max
number

optional

default value

22

The maximum zoom level at which individual observations are displayed. Must be in the range 0 to 22 where 0 is fully zoomed out and 22 is fully zoomed in.

min
number

optional

default value

14

The minimum zoom level at which individual observations are displayed. Must be in the range 0 to 22 where 0 is fully zoomed out and 22 is fully zoomed in.

minimumRadiusMeters
number

optional

default value

1

Minimum radius of individual observations in meters. If set alongside radiusPixels, the option that creates the largest circle will be used.

radiusPixels
number

optional

default value

2

Radius of individual observations in pixels. If set alongside minimumRadiusMeters, the option that creates the largest circle will be used.

style

optional

default value

'auto'

The style of the observations layer.

timeFilterRange

optional

default value

null

The time filter range. If non-null, observations will be hidden if their time is fully outside the range.

timeForegroundRange

optional

default value

null

Defines the time range of the observations to be foregrounded, which emphasizes foregrounded observations by fading the rest into the background. If set, will override timeFilterRange.

trackerNodes

object

optional

Options applied to tracker nodes, which are associated with an entity by a shared id. See the Tracker Nodes docs for more.

currentTime
number | Date

optional

default value

null

The time at which to place a tracker node on a trajectory as a Date in local time or a millisecond number in UTC.

networkLayerId
string

optional

default value

null

The id of a NetworkLayer. Nodes in NetworkLayerData with an id that matches an entityId will have their position constrained to the corresponding trajectory.

trajectory

object

optional

Options applied when observations are shown as a trajectory. See the Trajectory docs for more.

autoRange
object

optional

Defines the range of zoom levels where trajectories are displayed when ObservationsLayerStyle is set to 'auto'.

max
number

optional

default value

22

The maximum zoom level at which trajectories are displayed. Must be in the range 0 to 22 where 0 is fully zoomed out and 22 is fully zoomed in.

min
number

optional

default value

0

The minimum zoom level at which trajectories are displayed. Must be in the range 0 to 22 where 0 is fully zoomed out and 22 is fully zoomed in.

maximumInterval
number

optional

default value

60000

Two observations must occur in a specified time period to be considered as part of the same trajectory. This value defines this interval, in milliseconds.

minimumWidthMeters
number

optional

default value

0.5

Minimum width of trajectory lines in meters. If set alongside widthPixels, the option that creates the thickest line will be used.

opacity
number

optional

default value

1

Opacity of trajectory lines. Must be in the range 0 to 1 where 0 is transparent and 1 is fully visible.

widthPixels
number

optional

default value

1

Width of trajectory lines in pixels. If set alongside minimumWidthMeters, the option that creates the thickest line will be used.


ObservationsLayerStyle

ObservationsLayerStyle

"individual" | "trajectory" | "auto"

Defines how individual observations and trajectories are shown. If set to 'auto', the individual observations are displayed as defined in individual.autoRange and trajectories are displayed as defined in trajectory.autoRange.


ObservedEntity

Defines the entity that is observed. Each entity can relate to one or more observations.

Properties

color

string

optional

default value

'white'

The color of the entity shown on the map.


Trajectory

Defines an inferred path from more than one observation of the same entity.

Properties

entityId

string

The id of the entity.

observations

The observations of the entity in time order.

type

"trajectory"

The type of the item.