VGFILE

     VGFILE is the name of the Vector Graphics File (VGF) to be displayed
     or processed.  It also specifies the name of the scale file, 
     attribute file and time filter. The scale file and attribute file are 
     used by GPMAP to alter objects in the VGF when displayed or stored in 
     the output device, e.g., XW, FAX, GIF, etc.  These files allow the VGF 
     object attributes to be tailored to meet the display requirements of 
     FAX, GIF, and other supported product formats.  The scale, attribute 
     file names and filter are specified using the "|" character as a 
     delimiter in the following format:

		vgfile | scale file | attribute file | filter

     Specifying the scale file allows a limited set of object attributes
     in the VGF to be changed in the output device by multiplying their 
     values by numbers defined in the scale file.  The following parameters 
     can be scaled:

	Parameter Name		Description
	--------------		-----------

	PIPSIZE			Front Pip Size
	FRONTSTRENGTH		Frontal strength
	SYMWIDTH		Symbol width
	SYMSIZE			Symbol size
	WINDWIDTH		Wind barb/arrow width
	WINDSIZE		Wind barb/arrow size
	WINDHDSIZ		Wind barb head size
	LINEWIDTH		Line width  
	SPLWIDTH		Special line width
	SPLSIZE			Special line pattern size
	TEXTSIZE		Text size
	TEXTWIDTH		Text width
	SPTXTSIZE		Special text size
	SPTXTWIDTH		Special text width

     The parameter name must appear in the scale file followed by an 
     equal sign, "=", and a real value.  See the table 
     $GEMTBL/pgen/scale.fax for examples.

     Specifying the attribute file allows VGF object attributes to be
     modified for output devices by setting their values.  Attributes such 
     as color, size, thickness, etc. can be changed for particular object 
     sub-types, e.g., cold fronts.  Also, sub-types can be eliminated from 
     the output device by setting their major color number to -1. 

     The value of the attribute for an object in the attribute file
     overrides the value in the VGF with the following exceptions:

        1.  If the value for an attribute is set to 0, then it is not 
            changed except in the case of smoothing. 
        2.  If the attribute file value for smoothing is -1, then 
            smoothing remains unchanged.
        3.  Rotation values in the attribute file are ignored.

     The attribute file can also be used to change the object sub-type.  
     For example, all underlined text objects can be changed to non-underlined
     text objects.  

     The attribute file uses a similar format as the table 
     $GEMTBL/pgen/setting.tbl.  The file, $GEMTBL/pgen/uattribd.tbl
     provides a sample template for the attribute file and additional 
     instructions.

     Specifying the filter allows the vg elements with an embedded time 
     (i.e. GFA) to be selectively displayed. The filter value is a time 
     or times, with ";" used to delimit the the filter times. If the 
     time filter is not specified, all elements will be displayed.