Description | Example | Return message | Group

Cov Grid

Define a coverage grid

Syntax

Cov <CovDefnObjectPath> Grid {GridOption} <Parameters>

Related commands

Cov Access

Description

The Cov Grid command enables you to define the boundaries of the coverage region, set the granularity of the grid points used to fill the bounded region in the 2D Graphics window, and further define the properties of the grid points.

After setting the grid options, use the Cov Access command to compute coverage accesses.

The following table describes {GridOption} values:

{GridOption}	<Parameters>	Description
AreaOfInterest	Global	N/A
	LatLonRegion <MinLat> <MinLon> <MaxLat> <MaxLon>	Creates a grid in an area between the user-specified minimum and maximum boundaries for both latitude and longitude. All values are entered in degrees. Valid <MinLat> and <MaxLat> values are -90 to 90. Valid <MinLon> and <MaxLon> values are -360 to 360.
	LatBounds <MinLat> <MaxLat>	Creates a grid between the user-specified minimum and maximum latitude boundaries. All values are entered in degrees, valid <MinLat> and <MaxLat> values are -90 to 90.
	LonLine <MinLat> <MaxLat> <Lon>	Creates a set of points along a single meridian. The <MinLat> must be less than and not equal to <MaxLat>. All values are entered in degrees. Valid <Lon> value is -360 to 360, valid <MinLat> and <MaxLat> values are -90 to 90.
	LatLine <StartLon> <StopLon> <Latitude>	Creates a set of points along a single latitude line. The <StartLon> must not be equal to <StopLon>. All values are entered in degrees. Valid <Latitude> value is -90 to 90, valid <StartLon> and <StopLon> values are -360 to 360.
	Custom {Type} <Value> [{Type} <Value>...] [({Option} <Parameter>)...]	Where {Type} can be AreaTarget or Region. If {Type} is AreaTarget then <Value> is an AreaTarget object truncated path. If {Type} is Region then <Value> is a region file or shapefile path, enclosed in quotes. The file can have a path to a file on your local drive or the path to a file on an SDF server. See Specifying Paths for "<SDFFilePath>" syntax information. If entered, the shapefile must include polygons. The following list describes the valid values for {Option} <Parameter> CheckForHoles {On \| Off} - If On, STK will determine whether points are inside or outside of each contour. When Off, every region is treated as a closed boundary. SmallRegionAlgorithm {Disable \| Isotropic \| Anisotropic} - Disables or enables one of the two special gridding algorithms triggered when Custom Region grid includes a single small region (longitude span less than 1 deg).
CustomBoundary {Type} <Value> [{Type} <Value>...]	Where {Type} can be AreaTarget, LineTarget or Region. If {Type} is AreaTarget, then <Value> is an AreaTarget object truncated path. If {Type} is LineTarget, then <Value> is a LineTarget object truncated path. If {Type} is Region, then <Value> is a region file or shapefile path, enclosed in quotes. If entered, the shapefile must include polygons.
PointGranularity	LatLon <Degree>	A valid value is between approximately 0.00001 and 20.0 degrees.
	Distance <DistanceValue>	The <DistanceValue> is entered in Connect distance units. A valid value is between 1.0 meter and the equivalent of 20 degrees, which on Earth is approximately 2.22639e+06 meters.
	Area <AreaValue>	The <AreaValue> is entered in Scenario distance units squared. A valid value is between 1.0 meters squared and the equivalent of 20 degrees squared, which on Earth is approximately 4.95681e+012 meters squared.
PointLocation	UseGranularity	Determine point locations based on PointGranularity.
	Custom "<FilePath>" ["<FilePath>"...]	Specify one or more shapefiles to identify the points. Any previous list of point files will be cleared and replaced by the files specified here. The shapefile must contain points, not polygons.
	SetPointsLLA <NumberOfPoints> <LatValue> <LonValue> <AltValue> [<LatValue2> <LonValue2> <AltValue2>....]	<NumberOfPoints> is an integer specifying the number of sets of <LatValue> <LonValue> <AltValue> to follow. <LatValue> <LonValue> are latitude and longitude specified in degrees. <AltValue> is altitude specified in Connect distance units
PointAltitude	{AltitudeType} <AltitudeValue>	The <AltitudeValue> is entered in Connect distance units. The following list describes the {AltitudeType} values and the <AltitudeValue> limits for each type. Radius - <AltitudeValue> represents the distance from the center of the Earth and must be at least as large as the equatorial radius of the Earth (6378.137 km). Altitude - <AltitudeValue> is a positive value. AltAboveTerrain - <AltitudeValue> is a positive value. AltAboveMSL - <AltitudeValue> is a positive value. This option is valid only if the coverage object's Central Body is Earth.
CustomPointAltitudeMethod	{AltMethod}	Where {AltMethod} can be UseFileValues or Override. If {AltMethod} is UseFileValues then the altitude and altitude reference surface are taken from the file containing the custom grid point locations. If {AltMethod} is Override then the altitude and altitude reference surface are taken from the CoverageDefinition settings. The Override behavior is always followed for custom point files which do not contain altitude information. This option only affects CoverageDefinition objects which are using custom specified grid point locations.
GridConstraint	{PointObjectClass} [{AltitudeType} [<AltitudeValue>]] [<TruncObjectPath> [UseActualObject]]	Valid values for {PointObjectClass} are: Target, Facility, Place, Aircraft, GroundVehicle, Ship, Satellite, Radar, Receiver, Transmitter. The following "GridConstraint Option" section describes the valid paramaters for the {PointObjectClass} values in more detail.

GridConstraint Option

If {GridOption} is GridConstraint, this table describes the valid parameters for the {PointObjectClass} values.

{PointObjectClass}	<Parameters>
Target	{AltitudeType} [<AltitudeValue>] [<TruncObjectPath> [UseActualObject]] The <AltitudeValue> is entered in Connect distance units. The following list describes the {AltitudeType} values and the <AltitudeValue> limits for each type. UsePointAltitudeType - Do not include <AltitudeValue>. This option indicates that the type set for the Grid PointAltitude should be used. AltAtTerrain - Do not include <AltitudeValue> AltAboveEllipsoid - <AltitudeValue> is a positive value. AltAboveMSL - <AltitudeValue> is a positive value. This option is valid only if the coverage object's Central Body is Earth. If the GridConstraint {AltitudeType} matches the PointAltitude {AltitudeType}, then the GridConstraint <AltitudeValue>, if entered, must be less than or equal to the PointAltitude <AltitudeValue>.
Facility
Place
Aircraft	[<TruncObjectPath> [UseActualObject]]
GroundVehicle
Ship
Satellite
Radar	<TruncObjectPath> [UseActualObject] The <TruncObjectPath> is required if point class is Radar, Receiver or Transmitter.
Receiver
Transmitter

{AltitudeType} <AltitudeValue> is valid for Target, Facility and Place only.

Use the <TruncObjectPath> to specify a specific object rather than an object class for the point template.

The class of the object specified by <TruncObjectPath> must match the specified {PointObjectClass}.

Specify UseActualObject to use the actual object for grid points, rather than a copy of the object.

Deprecated Options

The following {GridOption} values have been replaced or renamed in STK 9 to match the updated UI. If you have commands using the pre-STK 9 options they should continue to operate as usual.

Pre-STK 9 Option	Current Option
Definition	AreaOfInterest
Resolution	PointGranularity
PointDef	Replaced by PointLocation, PointAltitude and GridConstraint

Examples

To define a custom grid that covers areas for both the continental US area target and the SouthAmerica region list:

Cov */CoverageDefinition/Americas Grid AreaOfInterest Custom AreaTarget AreaTarget/ContUS Region "C:\stk\User\Data\CovDemo\SouthAmerica.rl"

To define a custom grid with a latitude/longitude resolution of 5 degrees:

Cov */CoverageDefinition/Americas Grid PointGranularity LatLon 5

Define the Coverage grid along latitude -16 degrees, between -34 and 120 degrees longitude:

Cov */CoverageDefinition/cd Grid AreaOfInterest LatLine -34 120 -16

Define a CustomBoundary Coverage grid with an AreaTarget, LineTarget and region file:

Cov */CoverageDefinition/testCov Grid AreaOfInterest CustomBoundary AreaTarget AreaTarget/ContUS LineTarget LineTarget/LT1 Region "C:\stk\User\Data\CovDemo\SouthAmerica.rl"

Define the Points for TestCovDef from the specified file:

Cov */CoverageDefinition/TestCovDef Grid PointLocation Custom "C:\STKTest\STK\Scenarios\CovDefTest\Sample.pnt"

Define the Point Altitude as 10.0 m above Terrain:

Cov */CoverageDefinition/TestCovDef Grid PointAltitude AltAboveTerrain 10.0

To define the grid constraint for TestCovDef:

Cov */CoverageDefinition/TestCovDef Grid GridConstraint Facility AltAtTerrain Facility/CovDefTest

Cov */CoverageDefinition/TestCovDef Grid GridConstraint Satellite Satellite/CovDefTest1 UseActualObject

Define a grid custom region, with options:

Cov */CoverageDefinition/CovDef1 Grid AreaofInterest Custom Region "C:\stk\User\SouthAmerica.rl" CheckForHoles On SmallRegionAlgorithm Isotropic

Return message

CustomPointAltitudeMethod

Group membership

This command belongs to the following group(s):

Coverage

Version

11.6