NAME

       Tk_GetDash  - convert from string to valid dash structure.


SYNOPSIS

       #include <tk.h>

       int
       Tk_GetDash(interp, string, dashPtr)


ARGUMENTS

       Tcl_Interp           *interp(in)
                                      Interpreter  to   use   for
                                      error reporting.

       CONST char *         string(in)
                                      Textual  value  to  be con­
                                      verted.

       Tk_Dash   *dashPtr   (out)     Points to  place  to  store
                                      the dash pattern value con­
                                      verted from string.
_________________________________________________________________



DESCRIPTION

       These procedure parses the string and fills in the  result
       in  the  Tk_Dash  structure.  The  string can be a list of
       integers or a character string containing only  [.,-_]  or
       spaces.  If  all  goes well, TCL_OK is returned. If string
       doesn't have the proper syntax then TCL_ERROR is returned,
       an  error message is left in the interpreter's result, and
       nothing is stored at *dashPtr.

       The first possible syntax is a list of integers. Each ele­
       ment  represents  the  number of pixels of a line segment.
       Only the odd segments are drawn using the "outline" color.
       The other segments are drawn transparent.

       The  second possible syntax is a character list containing
       only 5 possible characters [.,-_ ]. The space can be  used
       to  enlarge the space between other line elements, and can
       not occur as the first posibion in the string. Some  exam­
       ples:
           -dash .     = -dash {2 4}
           -dash -     = -dash {6 4}
           -dash -.    = -dash {6 4 2 4}
           -dash -..   = -dash {6 4 2 4 2 4}
           -dash {. }  = -dash {2 8}
           -dash ,     = -dash {4 4}

       The  main  difference  of this syntax with the previous is
       display. This assures that "." will always be displayed as
       a  dot  and  "-"  always  as a dash regardless of the line
       width.

       On systems where only a limited set of dash patterns,  the
       dash pattern will be displayed as the most close dash pat­
       tern that is available. For example, on Windows  only  the
       first  4  of  the above examples are available. The last 2
       examples will be displayed identically as the first one.



KEYWORDS

       dash, conversion