use CWD;
use Tk;

@myorfs = ([1,'foo1',1000,850],[2,'foo2',750,600],[3,'foo3',575,375],[
+4,'moo1',350,10]);
@colors = qw/grey purple pink blue turquoise green chartreuse yellow g
+old orange/;
$canvas_height = 800;
$canvas_width  = 800;

$mw = MainWindow->new();
$canvas = $mw->Canvas(-height=>$canvas_height, -width=> $canvas_width,
+ -background=> 'white')->pack();

$radius = 200;            # radius is 200 pixels
$pi = 3.1417;             # Approximate pi
$deg2rad = $pi/180;       # conversion factor to go from degrees to ra
+dians
$circum = 2*$pi*$radius;  # C = 2 * pi * radius

$genome_length=0;

for ($i=0;$i<($#myorfs+1);$i++)
{
   $orf = $myorfs[$i][2] - $myorfs[$i][3];
   $genome_length = $genome_length + $orf;    # find genome length
}
print"genome length=$genome_length\n";

$drawn_angle=0;
$canvas->createLine($canvas_width/2,                  # draw a line wh
+ere start point should be
                    $canvas_height/2-$radius,
                    $canvas_width/2,
                    $canvas_height/2-$radius-30);

$canvas->createText($canvas_width/2,                  # draw "start" a
+t end of the line
                    $canvas_height/2-$radius-35,
                    -text=>"Start");

for ($i=0;$i<($#myorfs+1);$i++)
{
   $color = int($i % 10);
   $arcolor = $colors[$color];
   $orig_dist = $myorfs[$i][2] - $myorfs[$i][3];   # calc original orf
+ length
   $orf_pct = $orig_dist/$genome_length;           # convert orf lengt
+h to pct of genome length
   $graph_arc_length = $circum * $orf_pct;         # calc equivalent a
+rc length corresponding to same pct of circumference
   $central_angle = 360 * ($graph_arc_length / $circum); # calc centra
+l angle for that arc
   $gene_name = $myorfs[$i][1];

   if ($i == 0 )
   {
      $canvas->createArc($canvas_width  / 2 - $radius,   # draw first 
+arc all the way around circle
                         $canvas_height / 2 - $radius,   # set drawn_a
+ngle = angle you want this orf to be
                         $canvas_width  / 2 + $radius,   # It will be 
+used to set the extent for the next arc
                         $canvas_height / 2 + $radius,   # drawn, leav
+ing the right arc length exposed for this orf.
                         -width  => 4,
                         -outline=> $arcolor,
                         -style  => 'arc',
                         -start  => 90,
                         -extent => -359.99999999);
      $drawn_angle = 360 - $central_angle;
   }
   else
   {
      $canvas->createArc($canvas_width  / 2 - $radius,   # draw all of
+ the other arcs on top of the first arc
                         $canvas_height / 2 - $radius,
                         $canvas_width  / 2 + $radius,
                         $canvas_height / 2 + $radius,
                         -width  => 4,
                         -outline=> $arcolor,
                         -style  => 'arc',
                         -start  => 90,
                         -extent => -$drawn_angle);
      $drawn_angle = $drawn_angle - $central_angle;
   }

   $tick_length = 5;                                     # tick length
+ (supposedly)
   $xstart = int($canvas_width/2.0 + $radius*cos($drawn_angle*$deg2rad
+));
   $ystart = int($canvas_height/2.0 + $radius*sin($drawn_angle*$deg2ra
+d));
   $xstop  = int($xstart + $tick_length*cos($drawn_angle*$deg2rad));
   $ystop  = int($xstop + $tick_length*sin($drawn_angle*$deg2rad));

   $canvas->createLine($xstart,$ystart,$xstop,$ystop);
   $canvas->createText($xstop,$ystop, -anchor=>'n', -text=>"$gene_name
+($xstop,$ystop)");

   print"=======================\ni=$i,color=$arcolor,gene=$gene_name,
+radius=$radius,circum=$circum,central angle=$central_angle,drawn_angl
+e=$drawn_angle\n";

}




MainLoop;
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