package Bio::Graphics::Glyph::hat;
# a simple inverted V (used by DAS)

use strict;
use base qw(Bio::Graphics::Glyph::line);

sub my_description {
    return <<END;
This glyph draws an inverted V spanning the feature.
END
}

sub draw_connector {
    my $self = shift;
    my $gd   = shift;
    my ($left,$right,$high,$low) = @_;
    my $fg = $self->fgcolor;
    my $center = ($high+$low)/2;
    my $middle = ($left+$right)/2;
    $gd->line($left,$center,$middle,$high,$fg);
    $gd->line($middle,$high,$right,$center,$fg);
}

1;

__END__

=head1 NAME

Bio::Graphics::Glyph::hat - The "hat" glyph

=head1 SYNOPSIS

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

=head1 DESCRIPTION

This glyph draws an inverted V parallel to the sequence segment. It is
different from other glyphs in that it is designed to work with DAS
tracks. The inverted V is drawn BETWEEN subparts as if you specified a
connector type of "hat".

=head2 OPTIONS

This glyph takes only the standard options. See
L<Bio::Graphics::Glyph> for a full explanation.

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

  -fgcolor      Foreground color	       black

  -outlinecolor	Synonym for -fgcolor

  -bgcolor      Background color               turquoise

  -fillcolor    Synonym for -bgcolor

  -linewidth    Line width                     1

  -height       Height of glyph		       10

  -font         Glyph font		       gdSmallFont

  -connector    Connector type                 0 (false)

  -connector_color
                Connector color                black

  -label        Whether to draw a label	       0 (false)

  -description  Whether to draw a description  0 (false)

  -strand_arrow Whether to indicate            0 (false)
                 strandedness

  -hilite       Highlight color                undef (no color)

=head1 BUGS

Please report them.

=head1 SEE ALSO

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

=head1 AUTHOR

Allen Day E<lt>day@cshl.orgE<gt>.

Copyright (c) 2001 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.

=cut