Enter a ZIP code to get a forecast:
Setup Location

WRN Logo

Symbol File (.smb)

Symbols files are used to plot various symbols that cannot be plotted with the text fonts.  This is especially handy for weather, cloud and pressure tendency symbols.

FORMAT

The symbol file contains a set of symbols defined by a simple character string such as "RW-".  Following the string is a set of X,Y points which describe the symbol. The points can define a line or an area to fill. The format is:

str0 x0,y0 x1,y1 x2,y2 ... D
     x0,y0 x1,y1 x2,y2 ... D
     ... $
str1 x0,y0 x1,y1 x2,y2 ... D
...

Where:

  • str0 -- The string that will be used to designate the symbol (ie "TRW-" for thunderstorms)
  • x0,y0 x1,y1 ... -- The coordinates used to draw the symbol.  These form a continuous line/polygon. The values for X and Y are floating point numbers between 0 and 1.
  • D -- The draw command
    • L -- Draw a line between the listed points
    • F -- Fill the area defined by the list of points
  • $ -- Terminates the draw commands for that symbol.

EXAMPLES

Here is a sample of the wx.smb file:

T .7,.8 .4,.5 .7,.2 .5,.2 L
  .7,.2 .7,.4 L $
RW- .4,.7 .5,.7 .5,.6 .4,.6 .4,.7 L
  .3,.5 .6,.5 .45,.2 .3,.5 L $
RW+ .4,.7 .5,.7 .5,.6 .4,.6 .4,.7 L
  .3,.5 .6,.5 .45,.2 .3,.5 L
  .35,.4 .55,.4 L $
RW .4,.7 .5,.7 .5,.6 .4,.6 .4,.7 L
  .3,.5 .6,.5 .45,.2 .3,.5 L
  .35,.4 .55,.4 L $
R+ .2,.6 .3,.6 .3,.5 .2,.5 .2,.6 L
  .6,.6 .7,.6 .7,.5 .6,.5 .6,.6 L
  .4,.8 .5,.8 .5,.7 .4,.7 .4,.8 L
  .4,.4 .5,.4 .5,.3 .4,.3 .4,.4 L $

WXP comes with several predefined symbol files:

Symbol File Description
wx.smb Standard weather symbols (SAO format)
pwx.smb Synoptic present weather symbols
ptend.smb Pressure tendency symbols
cl.smb Low cloud symbols
cm.smb Middle cloud symbols
ch.smb High cloud symbols
sev.smb Severe weather symbols

SEE ALSO


For further information about WXP, email technical-support@weather.unisys.com
Last updated by Dan Vietor on August 11, 1998