This is PNGgraph 1.15, a package to generate PNG charts, using Lincoln
Stein's GD.pm.  This is a direct port of GIFgraph 1.10 by Martien Verbruggen.

INSTALLATION

needed to install (also see TESTED PLATFORMS):

	perl 5.004
	GD > 1.20

to install:

	perl Makefile.PL
	make
	make test
	make install

NB: make test may report errors. If you are not using GD 1.20 this is
normal. Because of differences in the way GD implements fonts and
polygons in the various versions, the produced PNGs will differ very
slightly. If you see this behaviour, please 'make' the samples in the
samples directory, and check the produced PNGs visually. If they look
ok, then PNGgraph is ok.

to see some samples:

	cd samples
	make

That should generate a set of pngs, which you can view using the HTML
pages in the same directory (or whichever other way pleases you).

The documentation available is contained in PNGgraph.pm, as pod.

The latest release should normally be available from CPAN.

TESTED PLATFORMS (also see NOTES FOR WIN32)

Latest version:
- perl 5.005_03 on Linux 2.2.5-22 (RedHat 6.0, patched), GD 1.20

Version 1.01 (GIFgraph):
- perl 5.004_04 on Solaris 2.5.1, GD 1.15
- perl 5.004_02 for win32 by Gurusamy Sarathy, GD (1.14 I think)
- perl 5.004_04 HP-UX 10.20, GD 1.18 (Ronald Post)

AUTHOR

Martien Verbruggen
mgjv@comdyn.com.au
tgtcmv@chem.tue.nl

PNG PORT

Steve Bonds
sbonds@agora.rdrop.com

MOST IMPORTANT CHANGES SINCE VERSION 1.10

- Namespace change from GIFgraph --> Chart::PNGgraph
- No longer generates GIF format images due to Unisys LZW patent
- Supports TrueType fonts

MOST IMPORTANT CHANGES SINCE VERSION 1.04

- added bar_spacing option
- added limited support for numerical X axis for equidistant X values
  (NOT for a real numerical graph!), thanks to Scott Prahl.
- routines to automatically 'guess' nice upper and lower values for
  graphs have been replaced by one written by Scott Prahl

MOST IMPORTANT CHANGES SINCE VERSION 1.03

- Added mixed type graph.
  PNGgraph::mixed
  options types and default_type
- Added callback functionality to format y values
  option y_number_format
- Added control over axis label placement
  option [xy]_label_position

MOST IMPORTANT CHANGES SINCE VERSION 1.01

- Vertical printing of X axis labels
- CHANGED DEFAULTS for zero_axis and zero_axis_only
- Fixed problems with negative values, data ranges without 0, and
  printing of the x axis labels (I hope)
- No more support for perl 5.003. Since perl 5.005 is out, and I don't
  have a 5.003 here to test all the time, I won't support it anymore.

MOST IMPORTANT CHANGES SINCE VERSION 0.91

- Legends
- Support for negative numbers
- Ticks for X axis
- line types and widths
- Allow entries in data set to be undef (to skip them)
- Changed 'zero' angle for pie charts (was right, now is front/bottom)
- Definition of colours now possible. See PNGgraph::colour::read_rgb
  for details
- See file CHANGES for more

TODO

- 3d look for graphs
- logarithmic scaling
- numerical X axes (halfway there)
- Autoloading/splitting, etc

BUG FIXES IN THIS VERSION

See file BUGS

NOTES FOR WIN32

I have not tested the PNG port on Win32.  sbonds.

PNGgraph installs and runs well under Gurusamy Sarathy's port of perl
for win32, and its usage is exactly the same as documented.

The ActiveState port 5.003 for win32 can be used with Dave Roth's port
of GD for win32. This port, however has a peculiarity. It is
impossible to manipulate the png data in memory (the GD::Image::png()
method always writes to a file descriptor, instead of returning the
data). This makes the use of PNGgraph with that port impossible
without a lot of work.
This means that until someone ports GD for the ActiveState perl with
full support for all its functionality, PNGgraph will not work on
ActiveState's port 5.003. 

It may very well, and _should_ work on the 5.005 ports, although I
have personally not tested that yet.

THANKS

	Scott Prahl
	brian d foy
	Honza Pazdziora
	Dave Belcher
	Vegard Vesterheim

COPYRIGHT

Copyright (c) 1995-1997 Martien Verbruggen. All rights reserved.
Copyright (c) 1999 Steve Bonds.  All rights reserved.

This package is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.