TkGetDash(3) Tk Library Procedures TkGetDash(3)

NAME
       TkGetDash - convert from string to valid dash structure.

SYNOPSIS
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       int
       TTkkGGeettDDaasshh(interp, string, dashPtr)

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

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

       TkDash   *dashPtr   (out)     Points to place to store the  dash  pat-
                                      tern value converted from string.



DESCRIPTION
       These  procedure  parses  the  string  and  fills  in the result in the
       TkDash structure. The string can be a list of integers or a  character
       string  containing  only  [[..,,-]] or spaces. If all goes well, TCLOK is
       returned. If string doesn't have the proper syntax  then  TCLERROR  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  element  repre-
       sents the number of pixels of a line segment. Only the odd segments are
       drawn using the "outline" color. The other segments are drawn transpar-
       ent.

       The second possible syntax is a character list containing only 5 possi-
       ble 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 examples:
           -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  that  it  it
       shape-conserving.  This  means that all values in the dash list will be
       multiplied by the line width before 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 pattern that is available. For
       example, on Windows only the first 4 of the above examples  are  avail-
       able.  The  last  2 examples will be displayed identically as the first
       one.


KKEEYYWWOORRDDSS
       dash, conversion



Tk                                    8.3                        TkGetDash(3)