NAME

Math::PlanePath::StaircaseAlternating -- stair-step diagonals up and down

SYNOPSIS

 use Math::PlanePath::StaircaseAlternating;
 my $path = Math::PlanePath::StaircaseAlternating->new;
 my ($x, $y) = $path->n_to_xy (123);

DESCRIPTION

This path makes a staircase pattern up from Y axis down to the X and then back up again.

    10       46
              |
     9       47--48
                  |
     8       45  49--50
              |       |
     7       44--43  51--52
                  |       |
     6       16  42--41  53--54
              |       |       |
     5       17--18  40--39  55--...
                  |       |
     4       15  19--20  38--37
              |       |       |
     3       14--13  21--22  36--35
                  |       |       |
     2        2  12--11  23--24  34--33
              |       |       |       |
     1        3-- 4  10-- 9  25--26  32--31
                  |       |       |       |
    Y=0 ->    1   5-- 6   8-- 7  27--28  30--29

              ^
             X=0  1   2   3   4   5   6   7   8

Square Ends

Option end_type => "square" changes the path as follows, omitting one point at each end so as to square up the joins.

     9       42--43
              |   |
     8       41  44--45
              |       |
     7       40--39  46--47
                  |       |
     6        .  38--37  48--49
                      |       |
     5       14--15  36--35  50--...
              |   |       |
     4       13  16--17  34--33
              |       |       |
     3       12--11  18--19  32--31
                  |       |       |
     2        .  10-- 9  20--21  30--29
                      |       |       |
     1        2-- 3   8-- 7  22--23  28--27
              |   |       |       |       |
    Y=0 ->    1   4-- 5-- 6   .  24--25--26

              ^
             X=0  1   2   3   4   5   6   7   8

The effect is to shorten each diagonal by a constant 1 each time. The lengths of each diagonal still grow by +4 each time (or by +16 up and back).

FUNCTIONS

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

$path = Math::PlanePath::StaircaseAlternating->new ()

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.

SEE ALSO

Math::PlanePath, Math::PlanePath::Staircase, Math::PlanePath::DiagonalsAlternating

HOME PAGE

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

LICENSE

Copyright 2011, 2012 Kevin Ryde

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/>.