Obtain Perl DBI and connect with the DBD::Chart driver:

use DBI;
use strict;
my $dbh = DBI->connect('dbi:Chart:', undef, undef,                       
					{ PrintError => 1, RaiseError => 1 });

We now can create a pie chart, with various rugby football information, in exactly the same way we might create an Oracle table with DBD::Oracle, and then select from it afterwards:

my @game_plan = qw(points possesion penalties goals turnovers yardage);
my @game_values = (70, 64, 18, 16, 19, 22);
$dbh->do('CREATE TABLE gamepie (                
			Segment varchar(10), 
			First integer)');
my $sth = $dbh->prepare('INSERT INTO gamepie VALUES(?, ?)');
  
for (my $i = 0; $i <= $#game_plan; $i++) {
   $sth->execute($game_plan[$i], $game_values[$i]);
}
$sth = $dbh->prepare(
   "SELECT PIECHART, IMAGEMAP FROM gamepie
     WHERE WIDTH=700 AND HEIGHT=600 AND
           TITLE = 'Sample Pie Chart' AND
           SIGNATURE = 'Copyright(C) 2002, Jared Still' AND
           3-D=1 AND
           COLORS=(red, white, blue, lyellow, lgray, pink)"
);
$sth->execute;
my $row = $sth->fetchrow_arrayref;

Having created the chart in memory via the use of SQL, we now output it to a PNG file. We then drop the memory structure, as if dropping a table:

open(PIE, '>gamepie.png');
binmode PIE;
print PIE $$row[0];
close PIE;
  
$dbh->do('DROP table gamepie');

We now create a three-axis bar chart. In this particular example, we'll cover ancient English sites of special interest (at least to one of the authors):

$dbh->do('CREATE TABLE spiritaxis (
	Month char(3),
	Visitors integer,
	Monument varchar(11))');
  
my @months = qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec);
my @monuments = 
	qw(Stonehenge Avebury SilburyHill Glastonbury WhiteHorse);
	$sth = $dbh->prepare('INSERT INTO spiritaxis VALUES(?, ?, ?)');
	foreach my $month (@months) {
	foreach my $visitors (@monuments) {
      $sth->execute($month, 1 * int(rand(2000)), $visitors);
   }
}
$sth = $dbh->prepare(
   "SELECT BARCHART, IMAGEMAP 
      FROM spiritaxis
     WHERE WIDTH=700 AND HEIGHT=600 AND
           TITLE = 'Visitors Per Saturday' AND
           SIGNATURE = 'Copyright(C) 2002, Andy Duncan' AND
           X-AXIS = 'Month' AND
           Y-AXIS = 'Visitors' AND
           Z-AXIS = 'Monument' AND
           COLORS=(white) AND
           SHOWGRID = 1"
                    );
$sth->execute;
$row = $sth->fetchrow_arrayref;

As before, we output the chart's memory structure into a file and then reclaim the memory by dropping the table:

open(BAR, '>spiritaxis.png');
binmode BAR;
print BAR $$row[0];
close BAR;
  
$dbh->do('DROP table spiritaxis');

Read carefully through the install.doc document to ensure that the configuration provides all the options you require:

$ gzip -d jpegsrc.v6b.tar.gz
$ tar xvf jpegsrc.v6b.tar
$ cd jpeg-6b
$ vi README install.doc

You may be able to move straight into the following commands:

$ ./configure
$ make
$ make test

The test step compares several JPEG files, which come with the download, with program compilations. Several of these test images should resemble the rose seen earlier in Figure 3-7, which is also borrowed by Tk::JPEG for its own testing. Note, however, that the various .jpg files will be of different physical sizes because of lossy compression.

Once the testing is complete, we can move on to the installation:

$ make install
$ make install-lib

Our default installation, on Linux, put the library and C header files into /usr/lib and /usr/include rather than /usr/local/. You will want to be aware of this during installation, so we can pick up the library correctly later.

Unpack the download:

$ gzip -d gd-1.8.4.tar.gz
$ tar xvf gd-1.8.4.tar
$ cd gd-1.8.4

The best help is available by browsing the download's index.html file. In accordance with the instructions provided, we changed the Makefile in several ways. We added the JPEG library to the main required libraries:

#LIBS=-lgd -lpng -lz -lm
LIBS=-lgd -lpng -lz -ljpeg -lm

Because the JPEG libraries and C header files had defaulted to be installed in /usr/lib and /usr/include, our Makefile had to be adjusted accordingly:

INCLUDEDIRS=-I. -I/usr/include/freetype2 -I/usr/include/X11 \
 -I/usr/X11R6/include/X11 -I/usr/local/include -I/usr/include
LIBDIRS=-L. -L/usr/local/lib -L/usr/lib -L/usr/lib/X11 -L/usr/X11R6/lib

(When you install JPEG on your own setup, your defaults may set to /usr/local/lib and /usr/local/include. If this happened, then the previous changes to INCLUDEDIRS and LIBDIRS will be unnecessary.)

We then tried:

$ make
$ make install

This installed the main gd library and header files in the following places:

/usr/local/lib/libgd.a
/usr/local/include/gd.h

When you install gd, you also obtain the gddemo program. If you run this program, you'll find that it creates a new PNG file, demoout.png, directly from a supplied one, demoin.png, which is a snazzy picture of a space shuttle:

$ ./gddemo

If this fails to work the first time, you may have to play around with the LD_LIBRARY_PATH variable, for example:

$ export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib

The new file should be the original space shuttle, but overlaid with decorative imagery, as seen earlier on the right side of Figure 3-7.

Because we're relying on the gd module's being available, this step differs from the standard vanilla Perl configuration:

$ gzip -d GD-1.33.tar.gz
$ tar xvf GD-1.33.tar
$ cd GD-1.33
$ perl Makefile.PL

The preceding step will ask various questions. Your mileage may vary. (Before completing the installation of GD.pm, you may wish to acquire FreeType and XPM (X PixMap) support. Information is available in the GD.pm download bundle. If you aren't interested, just say no):

Build JPEG support? [y]
Build FreeType support? [y]
Build XPM support? [y]

Next, compile and test the module:

$ make
$ make test

During the test stage, we're looking for output similar to the following:

... 
All tests successful, 2 subtests skipped.
Files=1, Tests=10,  
0 wallclock secs ( 0.49 cusr +  0.06 csys =  0.55 CPU)

You may also want to complete an optional step to provide a helpful GD.html documentation file in the current directory:

$ make html

We're now ready to:

$ make install

The GD.pm Perl package should now be loaded and ready to fire.

Everything should run smoothly during this installation, because TK::PNG is expecting the zlib and PNG libraries to be just where we put them earlier. Well, that's the plan. For variations, scan the README file thoroughly for complete information:

$ gzip -d Tk-PNG-2.005.tar.gz
$ tar xvf Tk-PNG-2.005.tar
$ cd Tk-PNG-2.005
$ vi README
$ perl Makefile.PL
$ make

The make test step should pop up the PNG picture we showed back in Figure 3-7, as also used by the original libpng installation:

$ make test
...
All tests successful.
Files=1, Tests=4,  2 wallclock secs 
( 0.33 cusr +  0.03 csys =  0.36 CPU)

Now carry out the install:

$ make install

Let's wrap up by installing Tk::JPEG:

$ gzip -d Tk-JPEG-2.014.tar.gz
$ tar xvf Tk-JPEG-2.014.tar
$ cd Tk-JPEG-2.014

As with the PNG installation, the make test step should pop up the JPEG picture of the rose, shown in Figure 3-7, as seen with the earlier installation of the JPEG libraries. If this occurs, the launchpad is ready:

$ perl Makefile.PL
$ make
$ make test
$ make install

As earlier with the Perl/Tk download, connect your PC to the Internet and run the PPM program:

C:\> ppm

Now install the ActivePerl GD and Tk::JPEG packages by typing:

PPM> install GD
PPM> install Tk-JPEG
PPM> exit

For those who have waded through the Unix install, we're embarrassed to say that this is really all you have to do to get zlib, PNG, JPEG, gd, and GD.pm onto Win32. When the revolution comes, there shall be a reckoning!

Get hold of the latest download file, such as DBD-Chart-0.60.tar.gz, from:

http://www.cpan.org/authors/id/D/DA/DARNOLD

Unzip the tarball to the a temporary directory, such as:

C:\DBD-Chart-0.60

Go to the main ..\DBD directory where ActivePerl keeps its modules, and copy in DBD::Chart's main Chart.pm module. For example:

C:\DBD-Chart-0.60> cd C:\Perl\site\lib\DBD
C:\Perl\site\lib\DBD> copy C:\DBD-Chart-0.60\Chart.pm .

Now create a new subdirectory under ..\DBD, itself named Chart:

C:\Perl\site\lib\DBD> mkdir Chart

Enter this subdirectory, and copy Plot.pm to it from the..\Chart directory within the download area:

C:\Perl\site\lib\DBD> cd Chart
C:\Perl\site\lib\DBD\Chart> copy C:\DBD-Chart-0.60\Chart\Plot.pm .

This completes the Win32 installation of DBD::Chart. (We'll cover another way of installing larger pure-Perl modules, using NMAKE, in Chapter 6, where a slightly longer setup can save a lot of copying by hand.) To test our Tk::JPEG system, we fired up Orac to see if it could detect both DBD::Chart and Tk::JPEG as being successfully installed. The resulting, slightly lossy tablespace allocations chart is displayed in Figure 3-14.