NAME

       Bio::Graphics::Glyph::ruler_arrow - glyph for drawing an arrow as ruler (5' and 3' are
       marked as label)

SYNOPSIS

         See L<Bio::Graphics::Panel> and L<Bio::Graphics::Glyph>.

DESCRIPTION

       This glyph draws arrows.  Label, if requested, will be 5' and 3' at both ends and tick
       scale is printed if no_tick_label option is set and tick option set.  Depending on
       options, the arrows can be labeled, be oriented vertically or horizontally, or can contain
       major and minor ticks suitable for use as a scale.

   OPTIONS
       In addition to the common options, the following glyph-specific options are recognized:

         Option      Description               Default
         ------      -----------               -------

         -tick       Whether to draw major         0
                     and minor ticks.
                     0 = no ticks
                     1 = major ticks
                     2 = minor ticks
         -label      5' at start, 3' at end        0
                     above arrow
         -both       5', 3' above,                 0
                     and 3', 5' below arrow
         -direction  0 = ruler is plus strand      0
                     -1 = ruler is minus strand

         -parallel   Whether to draw the arrow     true
                     parallel to the sequence
                     or perpendicular to it.

         -northeast  Force a north or east         true
                     arrowhead(depending
                     on orientation)

         -east       synonym of above

         -southwest  Force a south or west         true
                     arrowhead(depending
                     on orientation)

         -west       synonym of above

         -double     force-doubleheaded arrow

         -base       Draw a vertical base at the   false
                     non-arrowhead side

         -scale      Reset the labels on the arrow false
                     to reflect an externally
                     established scale.

       Set -parallel to false to display a point-like feature such as a polymorphism, or to
       indicate an important location.  If the feature start == end, then the glyph will draw a
       single arrow at the designated location:

              ^
              |

       Otherwise, there will be two arrows at the start and end:

              ^              ^
              |              |

       Scale: Pass in a externally established scale to reset the labels on the arrow.  This is
       particularly useful for manually constructed images where the founding parameters of the
       panel are not 1-based.  For example, a genetic map interval ranging from 0.1 - 0.3 can be
       constructed by first multiplying every value by 100. Passing

         arrow(-scale=>100);

       will draw tick marks labelled appropriately to your external scale.

BUGS

       Please report them.

SEE ALSO

       Bio::Graphics::Panel, Bio::Graphics::Glyph, Bio::Graphics::Glyph::arrow,
       Bio::Graphics::Glyph::cds, Bio::Graphics::Glyph::crossbox, Bio::Graphics::Glyph::diamond,
       Bio::Graphics::Glyph::dna, Bio::Graphics::Glyph::dot, Bio::Graphics::Glyph::ellipse,
       Bio::Graphics::Glyph::extending_arrow, Bio::Graphics::Glyph::generic,
       Bio::Graphics::Glyph::graded_segments, Bio::Graphics::Glyph::heterogeneous_segments,
       Bio::Graphics::Glyph::line, Bio::Graphics::Glyph::pinsertion,
       Bio::Graphics::Glyph::primers, Bio::Graphics::Glyph::rndrect,
       Bio::Graphics::Glyph::segments, Bio::Graphics::Glyph::ruler_arrow,
       Bio::Graphics::Glyph::toomany, Bio::Graphics::Glyph::transcript,
       Bio::Graphics::Glyph::transcript2, Bio::Graphics::Glyph::translation,
       Bio::Graphics::Glyph::triangle, Bio::DB::GFF, Bio::SeqI, Bio::SeqFeatureI, Bio::Das, GD

AUTHOR

       Shengqiang Shu <sshu@bdgp.lbl.gov> Lincoln Stein <lstein@cshl.org>.

       Copyright (c) 2001 BDGP, Cold Spring Harbor Laboratory

       This library is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself.  See DISCLAIMER.txt for disclaimers of warranty.