Artha Chess v1.0 - Third-party notices
======================================

Artha Chess (c) 2026 Artha Chess. All rights reserved.

Artha Chess includes the third-party components listed below. Each one is
the property of its authors and is used under the licence named here. The
full licence texts are in this "licenses" folder, or at the address given.


BUILT-IN CHESS ENGINE (separate program)
----------------------------------------
Chess Challenge Engine - GNU General Public License v3.
Search adapted from Obsidian (gab8192); evaluation from Cheese (Patrice
Duhamel); uses python-chess (Niklas Fiekas), GPL-3.0-or-later.
Licence text, source code and build notes: the "engine" folder of this
installation.


PIECE SETS
----------
Chessnut pieces - Copyright 2015 Alexis Luengas.
  Apache License 2.0 (Apache-2.0.txt). https://github.com/LexLuengas/chessnut-pieces
  The original SVG files are included unmodified and drawn by the program.


PROGRAM COMPONENTS
------------------
Python 3.11 - Copyright (c) 2001 Python Software Foundation. All rights reserved.
  PSF License Version 2 and the third-party licences listed with it
  (bzip2, libffi, OpenSSL, xz, zlib, expat, mpdecimal, Tcl/Tk and others):
  Python-LICENSE.txt

pygame 2.6.1 - GNU Lesser General Public License v2.1 (LGPL-2.1.txt).
  https://www.pygame.org  Source: https://github.com/pygame/pygame
  pygame is used unmodified; its compiled modules and the SDL libraries are
  shipped as separate files in the program folder.

SDL 2.28.4, SDL_image 2.0.5, SDL_mixer 2.6.2, SDL_ttf 2.20.1
  Copyright (C) 1997-2023 Sam Lantinga <slouken@libsdl.org>.
  zlib licence (same terms as zlib-LICENSE.txt). https://www.libsdl.org

FreeType 2.11.1
  Portions of this software are copyright (c) 2021 The FreeType Project
  (www.freetype.org). All rights reserved.
  Used under the FreeType License (FTL), https://freetype.org/license.html

libjpeg
  This software is based in part on the work of the Independent JPEG Group.

libpng - Copyright (c) 1995-2023 The PNG Reference Library Authors and
  contributors. PNG Reference Library License version 2,
  http://www.libpng.org/pub/png/src/libpng-LICENSE.txt

zlib - Copyright (C) 1995-2022 Jean-loup Gailly and Mark Adler.
  zlib licence (zlib-LICENSE.txt).

libtiff - Copyright (c) 1988-1997 Sam Leffler; Copyright (c) 1991-1997
  Silicon Graphics, Inc. libtiff licence, https://libtiff.gitlab.io/libtiff/project/license.html

libwebp - Copyright (c) 2010, Google Inc. All rights reserved.
  BSD 3-Clause licence (terms below). https://chromium.googlesource.com/webm/libwebp

libogg - Copyright (c) 2002, Xiph.org Foundation.
opus, opusfile - Copyright (c) 2001-2013 Xiph.Org Foundation, Skype Limited,
  Octasic, Jean-Marc Valin, Timothy B. Terriberry, CSIRO, Gregory Maxwell,
  Mark Borgerding, Erik de Castro Lopo and contributors.
  BSD 3-Clause licence (terms below). https://xiph.org

libmodplug - public domain. https://github.com/Konstanty/libmodplug

PortMidi - Copyright (c) 1999-2000 Ross Bencina and Phil Burk;
  Copyright (c) 2001-2009 Roger B. Dannenberg. MIT-style licence,
  https://github.com/PortMidi/portmidi

OpenSSL 3.0 - Copyright (c) 1998-2024 The OpenSSL Project Authors.
  Apache License 2.0 (Apache-2.0.txt). https://www.openssl.org

Tcl/Tk 8.6 - Copyright (c) the Regents of the University of California,
  Sun Microsystems, Inc., Scriptics Corporation, ActiveState Corporation
  and other parties. Tcl/Tk licence: _tcl_data and _tk_data\license.terms

pyperclip - Copyright (c) 2014, Al Sweigart. BSD 3-Clause licence
  (pyperclip-LICENSE.txt).

PyInstaller bootloader - GPL-2.0 with the PyInstaller bootloader exception,
  which permits use in programs under any licence. https://pyinstaller.org


BSD 3-CLAUSE LICENCE TERMS (libwebp, libogg, opus, opusfile)
------------------------------------------------------------
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice,
   this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its
   contributors may be used to endorse or promote products derived from
   this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.