It has been some time since I last needed to dynamically create a bar or line chart from an arbitrary data source (in my case a database of network configuration events). Several years back I used Martien Verbruggen's GIFgraph module -- I see he has moved on to GD::Graph. Has a clear leader in terms of usability and attractive functionality emerged among the CPAN graph and chart modules?

UPDATE: Thanks to all those who responded; I checked out GD::Graph3d and found it very much to my liking. I decided to rebuild libgd on my Solaris 5.9 system to include the libpng and FreeType libraries, and I had quite a bit of difficulty before I realized that I needed to provide the LD_LIBRARY_PATH environment variable to my CGI script in order for it to find the proper GD libraries to produce the PNG images. I hadn't realized that environment variables need to be explicitly passed or set within Apache http://httpd.apache.org/docs/1.3/env.html. I ended up with dynamically-generated PNG images with support for TrueType fonts, which pleases me greatly. Here's a simple test script that produces a 3d bar, 3d line and pie chart from sample data, if anyone is interested:

#!/usr/local/bin/perl -w

use GD::Graph::bars3d;
use GD::Graph::lines3d;
use GD::Graph::pie3d;
use CGI qw/:standard :html3 center/;
use CGI::Carp qw(fatalsToBrowser);
use strict;

  print header;
  print start_html(-title=>"3D Graph Test");
  my @data = ( 
           ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"],
           [ 1203,  3500,  3973,  2859,  3012,  3423,  1230],
           [ 819,  2500,  4901,  429,  1604,  2199,  700],
           [ 4412,  1500,  2211,  1394,  4501,  2290,  50],
        );

  my @graphs = ();
  my $width=300;
  my $height=200;
  print "<center><table border=0 cellpadding=10 cellspacing=10><tr>";

  $graphs[0] = new GD::Graph::bars3d( $width, $height );
  $graphs[1] = new GD::Graph::lines3d( $width, $height );
  $graphs[2] = new GD::Graph::pie3d( $width, $height );

  $graphs[0]->set ( 
                    bar_depth => 10,
                    bar_spacing => 10,
                    overwrite => 2,
                    cumulate => 1,
                    shading => 1 );
    
    $graphs[1]->set (
                    line_depth => 5,
                    shading => 3 );
                    
  for (my $i=0;$i<3;$i++) {
    $graphs[$i]->set ( 
          x_label           => 'Day of the week',
          y_label           => 'Number of hits',
                    zero_axis => 1,
                    box_axis => 0,
          title             => 'Daily Summary of Web Site',
    );
    $graphs[$i]->set_legend("Frank", "Bob", "Sue");
    $graphs[$i]->set_title_font('/usr/openwin/lib/locale/iso_8859_13/X
+11/fonts/TrueType/LucidaTypewriterBoldOblique.ttf', 8+$i*2);
    $graphs[$i]->set_legend_font(GD::Text::gdTinyFont);
    
    my $timeval = time() + $i;
    my $gd = $graphs[$i]->plot( \@data );
    my $image_stream = $gd->png();

    unless (open(GRAPH,">/up/web/data/testgraph${timeval}.png")) {
          die "Can't open /up/web/data/testgraph${timeval}.png: $!";
      }
      print GRAPH $image_stream;
      close(GRAPH);
    print qq|<td><img src="../data/testgraph${timeval}.png" alt="Test 
+chart"></td>|;
    }
  print "</tr></table></center>";
  print end_html();
[download]