Assignments

The Assignments dataframe is used as the input for the createCesium() function to generate time-dynamic visualization of vehicle routes on a 3D map.

While there is no “standard” function for generating all of the rows of an Assignments dataframe, VeRoViz does provide some functions that can be used to construct individual rows of the dataframe. Users may then append these rows into an Assignments dataframe. For example, getShapepoints2D() returns an assignment dataframe describing the detailed navigation on a road network between a pair of origin/destination locations. By iteratively calling that function for all O/D pairs of a route, a complete assignments dataframe can be constructed. Similarly, getShapepoints3D() returns an assignment dataframe describing the flight profile/path for aircraft (e.g., drones) for a given O/D pair.

A blank/empty Assignments dataframe can be created by initDataframe().

Field Name	Data Type	Description
odID	int	odID is an abbreviation for “origin/ destination identifier”. It is a group identifier. Arc segments which are part of the same origin/destination share the same odID.
objectID	string	Identifier for each object (e.g. truck, package, drone, etc.) shown in Cesium.
modelFile	string	The 3D model used for the object. See Cesium Style for a list of available 3D Cesium models . You can also generate your own gltf files.
modelScale	int	The scale of Cesium 3D model in percent.
modelMinPxSize	int	The minimum pixel size of Cesium 3D model
startTimeSec	int	In a sequence of coordinates that navigates between origin and destination, the time to arrive at the start coordinate ([startLat,startLon]).
startLat	float	Latitude of the start of the arc, in [degrees]. 0-degrees latitude is the equator. Negative latitudes are south of the equator; positive latitudes are north. The range is from -90 to +90.
startLon	float	Longitude of the start of the arc, in [degrees]. 0-degrees longitude is Greenich, England. Negative longitudes are west of Greenich; positive longitudes are east. The range is from -180 to +180.
startAltMeters	float	Altitude of the object at the start time, in units of [meters above ground level] (AGL).
endTimeSec	int	The arrival time (in seconds) to this coordinate ([endLat,endLon]).
endLat	float	Latitude of the end of the arc, in [degrees]. The range is from -90 to +90.
endLon	float	Longitude of the end of the arc, in [degrees]. The range is from -180 to +180.
endAltMeters	float	Altitude of the object at the end time, in units of [meters AGL].
leafletColor	string	Color of the arc when displayed in Leaflet. See Leaflet Style for options of colors.
leafletOpacity	float in [0, 1]	Amount of transparency for the arc. A value of 1 indicates no transparency; 0 indicates completely transparent.
leafletStyle	string	Styling of the line, valid options are “solid”, “dotted” or “dashed”. See Leaflet Style for more details
leafletCurveType	string	The type of curve to be shown on a leaflet map for :ref:Arc dataframes (curves will not be applied to :ref:Assignments dataframes). The options are ‘Bezier’, ‘greatcircle’, and ‘straight’. If Bezier is provided, the leafletCurvature is also required. If greatcircle is provided, the arc follows the curvature of the Earth.
leafletCurvature	float in (-90, 90)	If leafletCurveType is ‘Bezier’, then leafletCurvature is required; otherwise this argument will not be used. The curvature specifies the angle between a straight line connecting the two nodes and the curved arc emanating from those two nodes. Therefore, this value should be in the open interval (-90, 90), although values in the (-45, 45) range tend to work best.
useArrows	bool	True if the arrows will be used when creating Leaflet map, False otherwise.
cesiumWeight	int	Pixel width of the line/arc.
cesiumColor	string	Color of the arc when displayed in Cesium. See Cesium Style for color options.
cesiumOpacity	float in [0, 1]	The amount of transparency for the arc. A value of 1 indicates no transparency; 0 indicates completely transparent.
cesiumStyle	string	Styling of the line, valid options are “solid”, “dotted” or “dashed”. See Cesium Style for options.
cesiumWeight	int	Pixel width of the line/arc.
ganttColor	string	The color to be displayed for this assignment in a Gantt chart. See the ganttColor() function for details, and see Cesium Style for color options.
popupText	string	Text (or HTML) that will be displayed when a user clicks on the arc in Leaflet or Cesium.
startElevMeters	float	Elevation of the start point, in units of meters above ground level.
endElevMeters	float	Elevation of the end point, in units of meters above ground level.
wayname	string	Name of the road segment between start and end points.
waycategory	string	Classification of the road segment. May include: ‘No category’, ‘Highway’, ‘Steps’, ‘Ferry’, ‘Unpaved road’, ‘Track’, ‘Tunnel’, ‘Paved road’, or ‘Ford’
surface	string	Classification of the ground surface of the road segment. May include: ‘Unknown’, ‘Paved’, ‘Unpaved’, ‘Asphalt’, ‘Concrete’, ‘Cobblestone’, ‘Metal’, ‘Wood’, ‘Compacted Gravel’, ‘Fine Gravel’, ‘Gravel’, ‘Dirt’, ‘Ground’, ‘Ice’, ‘Paving Stones’, ‘Sand’, ‘Woodchips’, ‘Grass’, or ‘Grass Paver’.
waytype	string	Classification of the road segment. May include: ‘Unknown’, ‘State Road’, ‘Road’, ‘Street’, ‘Path’, ‘Track’, ‘Cycleway’, ‘Footway’, ‘Steps’, ‘Ferry’, or ‘Construction’.
steepness	int	Varies from -5 to +5, with - (+) values indicating a downward (upward) slope. The absolute scale is: 0: ‘0%’, 1: ‘1-3%’, 2: ‘4-6%’, 3: ‘7-11%’, 4: ‘12-15%’, 5: ‘>16%’.
tollway	bool	Indicates whether the road segment has tolls.

Arcs and Assignments dataframes are similar, see Dataframes Comparison for the similarity and differences between them.

---

An Assignments dataframe can be used in createLeaflet(). The table below indicates whether a given field (column) of the dataframe is required/optional/ignored.

Note

Some explaination about “Required”, “Optional”, “Ignored”:

• “Required” means the function needs info from that field/column. That info can not be overridden by the function that uses the dataframe.

• “Optional” means the function will use the info from that field/column as a default value. However, some functions allow the user to temporarily “override” the optional values in the dataframe with different values provided in the function call.

• “Ignored” means the function neither needs nor uses info from that field/column.

Field Name	Required	Optional	Ignored
odID	✓
objectID	✓
modelFile			✓
modelScale			✓
modelMinPxSize			✓
startTimeSec			✓
startLat	✓
startLon	✓
startAltMeters			✓
endTimeSec			✓
endLat	✓
endLon	✓
endAltMeters			✓
leafletColor		✓
leafletOpacity		✓
leafletStyle		✓
leafletWeight		✓
leafletCurveType	✓
leafletCurvature	✓
useArrows		✓
cesiumColor			✓
cesiumOpacity			✓
cesiumStyle			✓
cesiumWeight			✓
popupText		✓
startElevMeters			✓
endElevMeters			✓
wayname			✓
waycategory			✓
surface			✓
waytype			✓
steepness			✓
tollway			✓

An Assignments dataframe can be used in createCesium() to generate a Cesium-based 4D WebGIS video. The video can be displayed on a Cesium web page.

Field Name	Required	Optional	Ignored
odID	✓
objectID	✓
modelFile	✓
modelScale	✓
modelMinPxSize	✓
icon	✓
startTimeSec	✓
startLat	✓
startLon	✓
startAltMeters	✓
endTimeSec	✓
endLat	✓
endLon	✓
endAltMeters	✓
leafletColor			✓
leafletOpacity			✓
leafletStyle			✓
leafletWeight			✓
leafletCurveType			✓
leafletCurvature			✓
useArrows			✓
cesiumColor		✓
cesiumOpacity		✓
cesiumStyle		✓
cesiumWeight		✓
popupText		✓
startElevMeters			✓
endElevMeters			✓
wayname			✓
waycategory			✓
surface			✓
waytype			✓
steepness			✓
tollway			✓

Note

The Assignments dataframe may have duplicated odID values for different paths. When veroviz.createLeaflet generates a Leaflet map, it will combine odID with objectID to form a new/unique odID.