NAME

       Math::PlanePath::File -- points from a file

SYNOPSIS

        use Math::PlanePath::File;
        my $path = Math::PlanePath::File->new (filename => 'foo.txt');
        my ($x, $y) = $path->n_to_xy (123);

DESCRIPTION

       This path reads X,Y points from a file to present in PlanePath style.  It's slightly
       preliminary yet but is handy to get numbers from elsewhere into a PlanePath program.

       The intention is to be flexible about the file format and to auto-detect as far as
       possible.  Currently the only format is plain text, with an X,Y pair, or N,X,Y triplet on
       each line

           5,6                   # X,Y
           123  5 6              # N,X,Y

       Numbers can be separated by a comma or just spaces and tabs.  Lines not starting with a
       number are ignored as comments (or blanks).  N values must be integers, but the X,Y values
       can be fractions like 1.5 too, including exponential floating point 1500.5e-1 etc.

FUNCTIONS

       See "FUNCTIONS" in Math::PlanePath for behaviour common to all path classes.

       "$path = Math::PlanePath::File->new (filename => "/my/file/name.txt")"
           Create and return a new path object.

       "($x,$y) = $path->n_to_xy ($n)"
           Return the X,Y coordinates of point number $n on the path.

       "$n = $path->xy_to_n ($x,$y)"
           Return the point number for coordinates "$x,$y".

           In the current code an "$x,$y" within a unit circle or square of a point from the file
           gives that point.  But perhaps in the future some attention could be paid to apparent
           spacing of points closer than that.

       "$bool = $path->x_negative()"
       "$bool = $path->y_negative()"
           Return true if there are any negative X or negative Y coordinates in the file.

       "$n = $path->n_start()"
           Return the first N in the path.  For files of just X,Y points the start is N=1, for
           N,X,Y data it's the first N.

       "$str = $path->figure()"
           Return a string name of the figure (shape) intended to be drawn at each $n position.
           In the current code if all X,Y are integers then this is "square", otherwise it's
           "circle".  But perhaps that will change.

SEE ALSO

       Math::PlanePath

HOME PAGE

       <http://user42.tuxfamily.org/math-planepath/index.html>

LICENSE

       Copyright 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Kevin Ryde

       This file is part of Math-PlanePath.

       Math-PlanePath is free software; you can redistribute it and/or modify it under the terms
       of the GNU General Public License as published by the Free Software Foundation; either
       version 3, or (at your option) any later version.

       Math-PlanePath is distributed in the hope that it will be useful, but WITHOUT ANY
       WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
       PURPOSE.  See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with Math-
       PlanePath.  If not, see <http://www.gnu.org/licenses/>.