Arrowheads

[Stephen Woodbridge]

Chip Taylor wrote:
> Ok this one seemed so simple but I have yet to get this to work.  The
> project I am working has a need to show traffic flow along a section of a
> road or highway.  Ideally the end result would be an arrowhead at the end of
> a line segment, but regularly spaced arrows along the line segment would
> also work.  The shape file is one that came from the public domain.  
> 
> Problem #1: creation of the arrowhead.  I would like the symbol to be
> derived from a Truetype font if possible.  I found a good arrow symbol in
> Wingdings at character #232.  I created a symbolset entry like this:
> 	SYMBOL 
> 		NAME "Arrow1" 
> 		TYPE TRUETYPE 
> 		FONT "Wingdings" 
> 		CHARACTER "&#232" 
> 		FILLED true 
> 		ANTIALIAS true 
> 		GAP -70 
> 	END
> When I reference this symbol, I get &#232 displayed instead of the symbol.
> When I use the "sans" font and the ">" symbol (not my optimum choice), the
> ">" displays along the line as it should.
> 
> Problem #2: adding only to the end of the line and only the desired end with
> the symbol properly oriented.  Haven't figured this one out!
> 
> Problem #3: if #2 isn't possible, then having the directional arrowhead
> appear periodically along the line is acceptable (like it does with the > in
> #1).  However, I cannot seem to control the orientation of the symbol.
> Along some segments of the line, the symbol will point one way and other
> segments it will point just the opposite.
> 
> Any ideas would be very welcome!
> 
> Chip Taylor
> 

Chip,

Notice that you will need symbols that point both left and right AND 
notice you left off the ';' from the CHARACTER definition.

Hope this helps,
   -Steve W

SYMBOL
NAME "one_way_from"
TYPE truetype
FONT arial-bold
CHARACTER ">"
#FONT "Wingdings"
#CHARACTER "è"
GAP -40
END

SYMBOL
NAME "one_way_to"
TYPE truetype
FONT arial-bold
CHARACTER "<"
#FONT "Wingdings"
#CHARACTER "&#???;"
GAP -40
END


   LAYER
     NAME "One_Way_Arrows"
     STATUS DEFAULT
     TYPE LINE
     CLASSITEM "DIRECTION"
     CLASS
       NAME "From"
       EXPRESSION "F"
       STYLE
         SYMBOL "one_way_from"
         COLOR 0 0 0
         SIZE 6
       END
     END
     CLASS
       NAME "To"
       EXPRESSION "T"
       STYLE
         SYMBOL "one_way_to"
         COLOR 0 0 0
         SIZE 6
       END
     END
   END