Resource: color_table

Resource color_table
Command Line -ct=color_table
Environment Variable wxpclrtable
Default Value wxp.clr

This resource is used to specify which color table files are to be used in the program. The graphics program allocates (locks in) all the colors listed in the file. Each graphics program has color resources to specify and change colors of various components of the plot. Color table files are ASCII files which list a color name along with its RGB (red, green, blue) color fractions (0-1). 

By default, WXP uses the following color table:

[ind] name      red    green   blue
     Black      0.0     0.0     0.0
     White      1.0     1.0     1.0
     Red        0.7     0.0     0.0
     Green      0.0     0.7     0.0
     Blue       0.0     0.0     0.7
     Yellow     1.0     1.0     0.3
     Cyan       0.0     0.7     0.7
     Magenta    0.7     0.0     0.7
     DGray      0.3     0.3     0.3
     LGray      0.7     0.7     0.7
     LRed       1.0     0.3     0.3
     LGreen     0.3     1.0     0.3
     LBlue      0.3     0.3     1.0
     Brown      0.7     0.7     0.0
     LCyan      0.3     1.0     1.0
     LMagenta   1.0     0.3     1.0

Even though only 16 colors are specified, a total of 256 colors can be allocated. If the index is not specified, the indices start with 0 and increment by one for each line in the file.  To change the color table, the color_table can be specified with a new color table filename that is formatted the same as the above list. More than one color table can be listed separated by commas.  The programs use color names based on the default color table so it is useful to have these colors in any color table that is used. 

Several color table files are provided with WXP:

Color Table Description
wxp.clr Default color table (16 colors)
sat.clr Satellite color table with 50 gray shades
rainbow.clr A rainbow scheme with 23 colors
rainbow2.clr A rainbow scheme with 46 colors
rainbow4.clr A rainbow scheme with 92 colors
radar.clr Radar image color table
gray25.clr 25 gray shades
gray100.clr 100 gray shades
gray200.clr 200 gray shades

Multiple Color Tables

If more colors are needed, more than one color table can be specified:

   -ct=rainbow.clr,wxp.clr

The color index of the second color table is offset by the maximum index in the first file to prevent overlap.


For further information about WXP, email technical-support@weather.unisys.com
Last updated by Dan Vietor on July 30, 1998