The mapViz application can be created from the command line for from a progam with the following call.
mapVizCreate,objectReference=objectReference,...keywords
Creating an instance of mapViz with this command does not allow the user to select the initial observer postion. However, this may be set from the observer position pull down menu.
Since, in reality, mapViz is an object program it is possible to return the mapViz object reference by setting the objectReference keyword to a name variable.
The available keywords on object creation are:
xsize = x size of map in pixels. Default value is 600 pixels.
ysize = y size of map in pixels. Default value is 300 pixels.
boxcolor = color index for the rubber band box. Default value is 3.
projection = projection name. Has to be a string with one of the following values.
'Orthographic'
'Satellite'
'Cylindrical'
'Mercator'
'Mollweide'
'HammerAitoff'
'MillerCylindrical'
'Perspective'
Details on each projection can be found in the IDL on-line help.
chartName = Title that will appear in system menu. If nothing is supplied then 'Map Viz' will appear in the title.
group_leader = group leader of widget that calls this if mapViz is called from another widget program.
xoffset = offset in x direction that the map will initially appear.
yoffset = offset in y direction that the map will initially appear.
userName = User name (as a string) that will be used to create and read a preferences file.
mapIsotropic = If this keyword is set then the map aspect ratio will be fixed at 1 degree latitude by 1 deg longitude.
zoomIsotropic = When set then the zoom box will have a 1 degree by 1 degree aspect ratio.
backgroundColor = Initial color of the map background specified as a color index.
In addition, lines, points, etc may be added with the command
mapVizAdd,pos1, pos2, pos3, ...keywords
Adding Data Layers
Lines
Points
Polygon
Trajectories
Images
Adds in data to be displayed as a line.
Calling Sequence
mapVizAdd,lonVariable,latVariable,displayType='line', ...keywords.
lonVariable and latVariable must be in degrees east.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
PSYM
The symbol used to mark each data point. Normally, PSYM is 0, data points are connected by lines, and no symbols
are drawn to mark the points. Set this keywordto the symbol index as shown in the table below to mark data points
with symbols. The keyword SYMSIZE is used to set the size of the symbols.
PSYM Value Plotting Symbol
1 Plus sign (+)
2 Asterisk (*)
3 Period (.)
4 Diamond
5 Triangle
6 Square
7 X
SYMSIZE
Specifies the size of the symbols drawn when PSYM is set. The default size of 1.0 produces symbols approximately
the same size as a character.
THICK
This keyword controls the thickness of the lines forming the axis and tick marks. A value of 1.0 is the default.
Adds in data to be displayed as a point or points.
Calling Sequence
mapVizAdd,lonVariable,latVariable,displayType='point' ...keywords.
lonVariable and latVariable may be either a scalar or an array in degrees east.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LABEL
Scalar or array of strings that will label the input points.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
PSYM
The symbol used to mark each data point. Normally, PSYM is 0, data points are connected by lines, and no symbols
are drawn to mark the points. Set this keywordto the symbol index as shown in the table below to mark data points
with symbols. The keyword SYMSIZE is used to set the size of the symbols.
PSYM Value Plotting Symbol
1 Plus sign (+)
2 Asterisk (*)
3 Period (.)
4 Diamond
5 Triangle
6 Square
7 X
SYMSIZE
Specifies the size of the symbols drawn when PSYM is set. The default size of 1.0 produces symbols approximately
the same size as a character.
THICK
This keyword controls the thickness of the lines forming the axis and tick marks. A value of 1.0 is the default.
Adds in data to be displayed as a polygon.
Calling Sequence
mapVizAdd,lonVariable,latVariable,displayType='polygon' ...keywords.
lonVariable and latVariable must be an array with values in degrees east.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
ORIENTATION
Set this keyword equal to an angle in degrees from horizontal (in the clockwise direction) to rotate the labels.
Adds in data to be displayed as a trajectory. A trajectory can be any data set with longitude, latitude, and altitude values.
Calling Sequence
mapVizAdd,lonVariable,latVariable,altitudeVariable, displayType='trajectory', ...keywords
lonVariable and latVariable must be in degrees east. The altitude Variable must be in earth radii.
Keywords - These keywords may also be controlled through the layer manager by double clicking on the line icon.
COLOR
The color index of the lines being drawn.
DISPLAYTYPE
Controls how mapViz displays the data layer.
LINESTYLE
This keyword indicates the line style used to draw lines; it indicates the line style of the lines used to connect
the data points. This keyword should be set to the appropriate index for the desired linestyle as described in
the following table.
Index Linestyle
0 Solid
1 Dotted
2 Dashed
3 Dash Dot
4 Dash Dot Dot Dot
5 Long Dashes
NAME
Set this keyword to a string describing the data layer. This name will only appear on the layer inspector. If not
name is specified mapViz will give it the name LayerX where X is the number of the data layer as it was added in.
e.g. Layer5 would be the fifth data layer added to the current mapViz session.
NOPLOT
Setting this keyword delays the replotting of the layers in mapViz. If this is not set then each layer is plotted
as it is added. For situations where a lot of layers are being added to the map this can lead to significant plotting
delays. WARNING! When using this keyword make sure that the last data layer added does not have this keyword set.
Otherwise the map will appear empty. If this does happen then just select the reset on the Global Details
pulldown.
PSYM
The symbol used to mark each data point. Normally, PSYM is 0, data points are connected by lines, and no symbols
are drawn to mark the points. Set this keywordto the symbol index as shown in the table below to mark data points
with symbols. The keyword SYMSIZE is used to set the size of the symbols.
PSYM Value Plotting Symbol
1 Plus sign (+)
2 Asterisk (*)
3 Period (.)
4 Diamond
5 Triangle
6 Square
7 X
SYMSIZE
Specifies the size of the symbols drawn when PSYM is set. The default size of 1.0 produces symbols approximately
the same size as a character.
THICK
This keyword controls the thickness of the lines forming the axis and tick marks. A value of 1.0 is the default.
Adds in data to be displayed as an image.
Calling Sequence
mapVizAdd,image, displayType='image', ...keywords
Keywords - These keywords may also be controlled through the layer manager by double clicking on the image icon.
LATMIN
The latitude corresponding to the first row of Image. The default is -90 degrees. Note also that -90° £
LATMIN < LATMAX £ 90°.
LATMAX
The latitude corresponding to the last row of Image. The default value is 90 degrees. Note also that -90° £
LATMIN < LATMAX £ 90°.
LONMIN
The longitude corresponding to the first (leftmost) column of the Image argument. Select LONMIN so that -180°
£ LONMIN £ 180°. The default value is -180.
LONMAX
The longitude corresponding to the last (rightmost) column of the Image argument. Select LONMAX so that it is larger
than LONMIN. If the longitude of the last column is equal to (LONMIN - (360. /Nx)) MODULO 360, it is assumed that
the image covers all longitudes (Nx being the total number of columns in the Image argument).
BILINEAR
Set this flag to use bilinear interpolation to soften edges in the returned image, otherwise, nearest neighbor
sampling is used.
COMPRESS
This keyword, the interpolation compression flag, controls the accuracy of the results from MAP_IMAGE. The default
is 4 for output devices with fixed pixel sizes. The inverse projection transformation is applied to each ith row
and column. Setting this keyword to a higher number saves time while lower numbers produce more accurate results.
Setting this keyword to 1 solves the inverse map transformation for every pixel of the output image.
SCALE
Set this keyword to the pixel/graphics scale factor for devices with scalable pixels (e.g., PostScript). The default
is 0.02 pixels/graphic coordinate. This setting yields an approximate output image size of 350 x 250. Make this
number larger for more resolution (and larger PostScript files and images), or smaller for faster, smaller, and
less accurate images.
MAX_VALUE
Data points with values equal to or greater than this value will be treated as missing data, and will be set to
the value specified by the MISSING keyword.
MIN_VALUE
Data points with values equal to or less than this value will be treated as missing data, and will be set to the
value specified by the MISSING keyword.
MISSING
The pixel value to set areas outside the valid map coordinates. If this keyword is omitted, areas outside the map
are set to 255 (white) if the current graphics device is PostScript, otherwise they are set to 0.