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

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

  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)

  -hilite       Highlight color                undef (no color)

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

  -point      Whether to draw an ellipse   feature width
              the scaled width of the
              feature or with radius
              point.

package Bio::Graphics::Glyph::dot;
# DAS-compatible package to use for drawing a ring or filled circle

use strict;
use base qw(Bio::Graphics::Glyph::generic);
use constant PI => 3.14159;
sub my_description {
    return <<END;
This glyph draws an ellipse the width of the scaled feature passed,
and height a possibly configured height (See Bio::Graphics::Glyph).
END
}
sub my_options {
    {
	point => [
	    'boolean',
	    undef,
	    'If true, draws a fixed-radius ellipse at the center of the feature,',
	    'regardless of the feature\'s length.'],
    }
}

sub draw {
  my $self = shift;
  my $gd = shift;
  my $fg = $self->fgcolor;

  # now draw a circle
  my ($left,$top) = @_;
  my ($x1,$y1,$x2,$y2) = $self->calculate_boundaries(@_);
  my $xmid   = (($x1+$x2)/2);  my $width  = abs($x2-$x1);
  my $ymid   = (($y1+$y2)/2);  my $height = abs($y2-$y1);

  # only point ovals allowed now
  my $r = $self->height;

  # Code to maintain compliancy with gd 1.8.4 
  # gd 1.8.4 does not support the ellipse() or filledEllipse() methods.
  # Let's maintain the filledEllipse approach for installations
  # using gd2 or for drawing images with GD::SVG
  # Otherwise, we will use fill as before.
  # The can() method fails with GD::SVG. Why?
  my $bg = $self->bgcolor;
  if ($gd->can('filledEllipse') || $gd =~ /SVG/ ) {
    $gd->filledEllipse($xmid,$ymid,$r,$r,$bg) if ($bg);
    # Draw the border (or unfilled ellipse)
    $gd->ellipse($xmid,$ymid,$r,$r,$fg);
  } else {
    # Let's draw a circle in the gd 1.8.4 manner
    $gd->arc($xmid,$ymid,$r,$r,0,360,$fg);
    $gd->fillToBorder($xmid,$ymid,$fg,$bg) if ($bg);
  }

  #how about a fuse for the bomb?
  #work in degrees, not radians.  So we define PI above
  if(defined $self->option('stem')){
    my $angle = $self->option('stem');

    $gd->line($xmid+($r/PI*sin($angle*PI/180)),
	      $ymid+($r/PI*cos($angle*PI/180)),
	      $xmid+($r*sin($angle*PI/180)),
	      $ymid+($r*cos($angle*PI/180)),$fg);
  }

  $self->draw_label($gd,@_) if $self->option('label');
}

1;

__END__