What is this?
=============

Xcftools is a set of fast command-line tools for extracting
information from the Gimp's native file format XCF. The tools
are designed to allow efficient use of layered XCF files as
sources in a build system that use 'make' and similar tools
to manage automatic processing of the graphics. These tools
work independently of the Gimp engine and do not require the
Gimp to even be installed.

 xcf2pnm  converts XCF files to ppm, pgm or pbm format,
          flattening layers if necessary. If the image
          contains transparency, an alpha map can be written
          to a separate file, or a background color can be
          specified on the command line.

 xcf2png  converts XCF files to PNG format, flattening
          layers if necessary. Transparency information
          can be kept in the image, or a background color
          can be specified on the command line.

 xcfinfo  lists information about layers in an XCF file.

The tools can either flatten an XCF file as given, or extract specific
layers named on the command line.

Portability
===========

The software was developed on an Intel-based PC running Debian
GNU/Linux. It ought to work on other Linux variants also. I would
not be surprised if it ran on other unix systems too, but porting
to non-unix platforms will require some work. Most of the code
attempts to be prepared for porting, but this has not been
explicitly tested.

Installation
============

You need GNU make, a C compiler, and perl.

After the source archive is extracted, the command sequence
   ./configure
   make all
   make install
should compile the tools and install them in /usr/local.

The 'configure' script is generated by GNU autoconf, and accepts
the arguments that such scripts commonly do.

You can use
  ./configure --enable-precomputed-scaletable
to precompute lookup tables for pixel composing at compile time.
Normally these tables are initialized at run time if a layer that
needs them is detected. Precomputing them may improve performance
by a few percent, at the cost of doubling the size of each binary.

License
=======

Xcftools is written by Henning Makholm <henning()makholm.net>
(Copyright 2006).

Xcftools is free software; you can redistribute it and/or modify
it under the terms of version 2 of the GNU General Public License as
published by the Free Software Foundation.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA