refactor special-case code for width 0 feature into base glyph

MANIFEST

@@ -59,6 +59,7 @@ lib/Bio/Graphics/Glyph/pairplot.pm
 lib/Bio/Graphics/Glyph/pentagram.pm
 lib/Bio/Graphics/Glyph/phylo_align.pm
 lib/Bio/Graphics/Glyph/pinsertion.pm
+lib/Bio/Graphics/Glyph/point_glyph.pm
 lib/Bio/Graphics/Glyph/primers.pm
 lib/Bio/Graphics/Glyph/processed_transcript.pm
 lib/Bio/Graphics/Glyph/protein.pm

lib/Bio/Graphics/Glyph/diamond.pm

@@ -2,7 +2,7 @@ package Bio::Graphics::Glyph::diamond;
 # DAS-compatible package to use for drawing a colored diamond
 
 use strict;
-use base qw(Bio::Graphics::Glyph::generic);
+use base qw(Bio::Graphics::Glyph::point_glyph);
 
 sub my_description {
     return <<END;
@@ -70,16 +70,6 @@ sub draw_component {
   }
 }
 
-sub box {
-  my $self = shift;
-  my @result = $self->SUPER::box();
-  return @result unless $self->option('point');
-  my $h   = $self->option('height')/2;
-  my $mid = int(($result[2]+$result[0])/2);
-  $result[0] = $mid-$h-1;  # fudge a little to make it easier to click on
-  $result[2] = $mid+$h+1;
-  return @result;
-}
 
 1;
 

lib/Bio/Graphics/Glyph/point_glyph.pm

@@ -0,0 +1,17 @@
+package Bio::Graphics::Glyph::point_glyph;
+
+use strict;
+use base qw(Bio::Graphics::Glyph::generic);
+
+sub box {
+  my $self = shift;
+  my @result = $self->SUPER::box();
+  return @result unless $self->option('point') && $result[2]-$result[0] < 3;
+  my $h   = $self->option('height')/2;
+  my $mid = int(($result[2]+$result[0])/2);
+  $result[0] = $mid-$h-1;  # fudge a little to make it easier to click on
+  $result[2] = $mid+$h+1;
+  return @result;
+}
+
+1;

lib/Bio/Graphics/Glyph/triangle.pm

@@ -2,7 +2,7 @@ package Bio::Graphics::Glyph::triangle;
 # DAS-compatible package to use for drawing a triangle
 
 use strict;
-use base qw(Bio::Graphics::Glyph::generic);
+use base qw(Bio::Graphics::Glyph::point_glyph);
 
 sub pad_left {
   my $self = shift;