mapgrid

This application will create a GML (Geography Mapping Language) file containing drawing instruction for a user defined latitude/longitude graticule (grid). The MAPFILE provides definition of map projection parameters while user input 'Options' define how specific latitude and lines are drawn. The resulting GML file can be viewed by various applications such as QGIS, Snowflake GML Viewer, GAIA, etc. In addition, GML files produced via this program can be manipulated by GDAL utilities for conversion to other usable formats. For example, the "ogr2ogr" utility can produce DXF and ESRI Shape files readable by Adobe Illustrator and Arc applications respectively.

Description

This file contains map projection information necessary to produce the grid. This can be a conventional or user defined ISIS mapping template or an existing projected ISIS cube.

Type	filename
File Mode	input
Filter	*.map *.cub *.txt

Description

The resultant GML file. This output file contains drawing instruction in GML form and can be viewed or plotted by various applications such as QGIS, Snowflake GML Viewer, GAIA, etc. In addition, GML files produced via this program can be manipulated by GDAL utilities for conversion to other usable formats. For example, the "ogr2ogr" utility can produce DXF and ESRI Shape files readable by Adobe Illustrator and Arc applications respectively.

Type	filename
File Mode	output
Filter	*.gml

Description

This defines the minimum or starting latitude to which longitude grid lines will extend.

Type	double

Description

This defines the minimum or starting longitude to which latitude grid lines will extend.

Type	double

Description

This defines the maximum or ending latitude to which longitude grid lines will extend.

Type	double

Description

This defines the maximum or ending longitude to which latitude grid lines will extend.

Type	double

Description

This value defines the spacing of latitude lines, starting with STARTLAT

Type	double
Default	10.0

Description

This value defines the spacing of longitude lines, starting with STARTLON

Type	double
Default	10.0

Description

This value sets the incremental definition of latitude lines. That is, it defines the frequency of how often a coordinate is calculated while drawing each latitude line. In general, a larger value will result in a more rough or jagged line, while a smaller value will result in a more smooth or curved line.

Type	double
Default	0.01

Description

This value sets the incremental definition of longitude lines. That is, it defines the frequency of how often a coordinate is calculated while drawing each longitude line. In general, a larger value will result in a more rough or jagged line, while a smaller value will result in a more smooth or curved line.

Type	double
Default	0.01

Description

This option will draw a rectangular box outlining the x-y extents of the entire grid.

Type	boolean
Default	TRUE

This example shows the qgis display of a sinusoidal projection created by this application. The following mapfile was used in the mapgrid application to create the grid.

Group = Mapping
  ProjectionName     = Sinusoidal
  TargetName         = MARS
  EquatorialRadius   = 3396190.0 <meters>
  PolarRadius        = 3376200.0 <meters>
  LatitudeType       = Planetocentric
  LongitudeDirection = PositiveEast
  LongitudeDomain    = 360
  CenterLongitude    = 180.0
End_Group
End
         

mapgrid mapfile=mapFile1.txt startlat=-90 endlat=90 startlon=0 endlon=360 to=sinuGrid.txt

Output image showing the results of the mapgrid application.

Output image as it appears in qgis for mapgrid Parameter Name: TO This is the output image that results.

This example shows the qgis display of a lambert conformal projection created by this application. The following mapfile was used in the this application to create the grid.

Group = Mapping
  ProjectionName         = LambertConformal
  TargetName             = MARS
  EquatorialRadius       = 3396190.0 <meters>
  PolarRadius            = 3376200.0 <meters>
  LatitudeType           = Planetocentric
  LongitudeDirection     = PositiveEast
  LongitudeDomain        = 360
  CenterLongitude        = 20.0
  CenterLatitude         = 40.0
  FirstStandardParallel  = 32.0
  SecondStandardParallel = 43.0
End_Group
End
         

mapgrid mapfile=mapFile2.txt startlat=20 endlat=60 startlon=0 endlon=40 to=lambGrid.txt

Output image showing the results of the mapgrid application.

Output image as it appears in qgis Parameter Name: TO This is the output image that results