diff --git a/LICENSE b/LICENSE
index 670154e..4362b49 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,116 +1,502 @@
-CC0 1.0 Universal
+ GNU LESSER GENERAL PUBLIC LICENSE
+ Version 2.1, February 1999
-Statement of Purpose
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
-The laws of most jurisdictions throughout the world automatically confer
-exclusive Copyright and Related Rights (defined below) upon the creator and
-subsequent owner(s) (each and all, an "owner") of an original work of
-authorship and/or a database (each, a "Work").
+[This is the first released version of the Lesser GPL. It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
-Certain owners wish to permanently relinquish those rights to a Work for the
-purpose of contributing to a commons of creative, cultural and scientific
-works ("Commons") that the public can reliably and without fear of later
-claims of infringement build upon, modify, incorporate in other works, reuse
-and redistribute as freely as possible in any form whatsoever and for any
-purposes, including without limitation commercial purposes. These owners may
-contribute to the Commons to promote the ideal of a free culture and the
-further production of creative, cultural and scientific works, or to gain
-reputation or greater distribution for their Work in part through the use and
-efforts of others.
+ Preamble
-For these and/or other purposes and motivations, and without any expectation
-of additional consideration or compensation, the person associating CC0 with a
-Work (the "Affirmer"), to the extent that he or she is an owner of Copyright
-and Related Rights in the Work, voluntarily elects to apply CC0 to the Work
-and publicly distribute the Work under its terms, with knowledge of his or her
-Copyright and Related Rights in the Work and the meaning and intended legal
-effect of CC0 on those rights.
+ The licenses for most software are designed to take away your
+freedom to share and change it. By contrast, the GNU General Public
+Licenses are intended to guarantee your freedom to share and change
+free software--to make sure the software is free for all its users.
-1. Copyright and Related Rights. A Work made available under CC0 may be
-protected by copyright and related or neighboring rights ("Copyright and
-Related Rights"). Copyright and Related Rights include, but are not limited
-to, the following:
+ This license, the Lesser General Public License, applies to some
+specially designated software packages--typically libraries--of the
+Free Software Foundation and other authors who decide to use it. You
+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
+strategy to use in any particular case, based on the explanations below.
- i. the right to reproduce, adapt, distribute, perform, display, communicate,
- and translate a Work;
+ When we speak of free software, we are referring to freedom of use,
+not price. Our General Public Licenses are designed to make sure that
+you have the freedom to distribute copies of free software (and charge
+for this service if you wish); that you receive source code or can get
+it if you want it; that you can change the software and use pieces of
+it in new free programs; and that you are informed that you can do
+these things.
- ii. moral rights retained by the original author(s) and/or performer(s);
+ To protect your rights, we need to make restrictions that forbid
+distributors to deny you these rights or to ask you to surrender these
+rights. These restrictions translate to certain responsibilities for
+you if you distribute copies of the library or if you modify it.
- iii. publicity and privacy rights pertaining to a person's image or likeness
- depicted in a Work;
+ For example, if you distribute copies of the library, whether gratis
+or for a fee, you must give the recipients all the rights that we gave
+you. You must make sure that they, too, receive or can get the source
+code. If you link other code with the library, you must provide
+complete object files to the recipients, so that they can relink them
+with the library after making changes to the library and recompiling
+it. And you must show them these terms so they know their rights.
- iv. rights protecting against unfair competition in regards to a Work,
- subject to the limitations in paragraph 4(a), below;
+ We protect your rights with a two-step method: (1) we copyright the
+library, and (2) we offer you this license, which gives you legal
+permission to copy, distribute and/or modify the library.
- v. rights protecting the extraction, dissemination, use and reuse of data in
- a Work;
+ To protect each distributor, we want to make it very clear that
+there is no warranty for the free library. Also, if the library is
+modified by someone else and passed on, the recipients should know
+that what they have is not the original version, so that the original
+author's reputation will not be affected by problems that might be
+introduced by others.
+
+ Finally, software patents pose a constant threat to the existence of
+any free program. We wish to make sure that a company cannot
+effectively restrict the users of a free program by obtaining a
+restrictive license from a patent holder. Therefore, we insist that
+any patent license obtained for a version of the library must be
+consistent with the full freedom of use specified in this license.
- vi. database rights (such as those arising under Directive 96/9/EC of the
- European Parliament and of the Council of 11 March 1996 on the legal
- protection of databases, and under any national implementation thereof,
- including any amended or successor version of such directive); and
+ Most GNU software, including some libraries, is covered by the
+ordinary GNU General Public License. This license, the GNU Lesser
+General Public License, applies to certain designated libraries, and
+is quite different from the ordinary General Public License. We use
+this license for certain libraries in order to permit linking those
+libraries into non-free programs.
- vii. other similar, equivalent or corresponding rights throughout the world
- based on applicable law or treaty, and any national implementations thereof.
+ When a program is linked with a library, whether statically or using
+a shared library, the combination of the two is legally speaking a
+combined work, a derivative of the original library. The ordinary
+General Public License therefore permits such linking only if the
+entire combination fits its criteria of freedom. The Lesser General
+Public License permits more lax criteria for linking other code with
+the library.
-2. Waiver. To the greatest extent permitted by, but not in contravention of,
-applicable law, Affirmer hereby overtly, fully, permanently, irrevocably and
-unconditionally waives, abandons, and surrenders all of Affirmer's Copyright
-and Related Rights and associated claims and causes of action, whether now
-known or unknown (including existing as well as future claims and causes of
-action), in the Work (i) in all territories worldwide, (ii) for the maximum
-duration provided by applicable law or treaty (including future time
-extensions), (iii) in any current or future medium and for any number of
-copies, and (iv) for any purpose whatsoever, including without limitation
-commercial, advertising or promotional purposes (the "Waiver"). Affirmer makes
-the Waiver for the benefit of each member of the public at large and to the
-detriment of Affirmer's heirs and successors, fully intending that such Waiver
-shall not be subject to revocation, rescission, cancellation, termination, or
-any other legal or equitable action to disrupt the quiet enjoyment of the Work
-by the public as contemplated by Affirmer's express Statement of Purpose.
+ We call this license the "Lesser" General Public License because it
+does Less to protect the user's freedom than the ordinary General
+Public License. It also provides other free software developers Less
+of an advantage over competing non-free programs. These disadvantages
+are the reason we use the ordinary General Public License for many
+libraries. However, the Lesser license provides advantages in certain
+special circumstances.
-3. Public License Fallback. Should any part of the Waiver for any reason be
-judged legally invalid or ineffective under applicable law, then the Waiver
-shall be preserved to the maximum extent permitted taking into account
-Affirmer's express Statement of Purpose. In addition, to the extent the Waiver
-is so judged Affirmer hereby grants to each affected person a royalty-free,
-non transferable, non sublicensable, non exclusive, irrevocable and
-unconditional license to exercise Affirmer's Copyright and Related Rights in
-the Work (i) in all territories worldwide, (ii) for the maximum duration
-provided by applicable law or treaty (including future time extensions), (iii)
-in any current or future medium and for any number of copies, and (iv) for any
-purpose whatsoever, including without limitation commercial, advertising or
-promotional purposes (the "License"). The License shall be deemed effective as
-of the date CC0 was applied by Affirmer to the Work. Should any part of the
-License for any reason be judged legally invalid or ineffective under
-applicable law, such partial invalidity or ineffectiveness shall not
-invalidate the remainder of the License, and in such case Affirmer hereby
-affirms that he or she will not (i) exercise any of his or her remaining
-Copyright and Related Rights in the Work or (ii) assert any associated claims
-and causes of action with respect to the Work, in either case contrary to
-Affirmer's express Statement of Purpose.
+ For example, on rare occasions, there may be a special need to
+encourage the widest possible use of a certain library, so that it becomes
+a de-facto standard. To achieve this, non-free programs must be
+allowed to use the library. A more frequent case is that a free
+library does the same job as widely used non-free libraries. In this
+case, there is little to gain by limiting the free library to free
+software only, so we use the Lesser General Public License.
-4. Limitations and Disclaimers.
+ In other cases, permission to use a particular library in non-free
+programs enables a greater number of people to use a large body of
+free software. For example, permission to use the GNU C Library in
+non-free programs enables many more people to use the whole GNU
+operating system, as well as its variant, the GNU/Linux operating
+system.
- a. No trademark or patent rights held by Affirmer are waived, abandoned,
- surrendered, licensed or otherwise affected by this document.
+ Although the Lesser General Public License is Less protective of the
+users' freedom, it does ensure that the user of a program that is
+linked with the Library has the freedom and the wherewithal to run
+that program using a modified version of the Library.
- b. Affirmer offers the Work as-is and makes no representations or warranties
- of any kind concerning the Work, express, implied, statutory or otherwise,
- including without limitation warranties of title, merchantability, fitness
- for a particular purpose, non infringement, or the absence of latent or
- other defects, accuracy, or the present or absence of errors, whether or not
- discoverable, all to the greatest extent permissible under applicable law.
+ The precise terms and conditions for copying, distribution and
+modification follow. Pay close attention to the difference between a
+"work based on the library" and a "work that uses the library". The
+former contains code derived from the library, whereas the latter must
+be combined with the library in order to run.
+
+ GNU LESSER GENERAL PUBLIC LICENSE
+ TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
- c. Affirmer disclaims responsibility for clearing rights of other persons
- that may apply to the Work or any use thereof, including without limitation
- any person's Copyright and Related Rights in the Work. Further, Affirmer
- disclaims responsibility for obtaining any necessary consents, permissions
- or other rights required for any use of the Work.
+ 0. This License Agreement applies to any software library or other
+program which contains a notice placed by the copyright holder or
+other authorized party saying it may be distributed under the terms of
+this Lesser General Public License (also called "this License").
+Each licensee is addressed as "you".
- d. Affirmer understands and acknowledges that Creative Commons is not a
- party to this document and has no duty or obligation with respect to this
- CC0 or use of the Work.
+ A "library" means a collection of software functions and/or data
+prepared so as to be conveniently linked with application programs
+(which use some of those functions and data) to form executables.
-For more information, please see
-
+ The "Library", below, refers to any such software library or work
+which has been distributed under these terms. A "work based on the
+Library" means either the Library or any derivative work under
+copyright law: that is to say, a work containing the Library or a
+portion of it, either verbatim or with modifications and/or translated
+straightforwardly into another language. (Hereinafter, translation is
+included without limitation in the term "modification".)
+
+ "Source code" for a work means the preferred form of the work for
+making modifications to it. For a library, complete source code means
+all the source code for all modules it contains, plus any associated
+interface definition files, plus the scripts used to control compilation
+and installation of the library.
+
+ Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope. The act of
+running a program using the Library is not restricted, and output from
+such a program is covered only if its contents constitute a work based
+on the Library (independent of the use of the Library in a tool for
+writing it). Whether that is true depends on what the Library does
+and what the program that uses the Library does.
+
+ 1. You may copy and distribute verbatim copies of the Library's
+complete source code as you receive it, in any medium, provided that
+you conspicuously and appropriately publish on each copy an
+appropriate copyright notice and disclaimer of warranty; keep intact
+all the notices that refer to this License and to the absence of any
+warranty; and distribute a copy of this License along with the
+Library.
+
+ You may charge a fee for the physical act of transferring a copy,
+and you may at your option offer warranty protection in exchange for a
+fee.
+
+ 2. You may modify your copy or copies of the Library or any portion
+of it, thus forming a work based on the Library, and copy and
+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
+ a) The modified work must itself be a software library.
+
+ b) You must cause the files modified to carry prominent notices
+ stating that you changed the files and the date of any change.
+
+ c) You must cause the whole of the work to be licensed at no
+ charge to all third parties under the terms of this License.
+
+ d) If a facility in the modified Library refers to a function or a
+ table of data to be supplied by an application program that uses
+ the facility, other than as an argument passed when the facility
+ is invoked, then you must make a good faith effort to ensure that,
+ in the event an application does not supply such function or
+ table, the facility still operates, and performs whatever part of
+ its purpose remains meaningful.
+
+ (For example, a function in a library to compute square roots has
+ a purpose that is entirely well-defined independent of the
+ application. Therefore, Subsection 2d requires that any
+ application-supplied function or table used by this function must
+ be optional: if the application does not supply it, the square
+ root function must still compute square roots.)
+
+These requirements apply to the modified work as a whole. If
+identifiable sections of that work are not derived from the Library,
+and can be reasonably considered independent and separate works in
+themselves, then this License, and its terms, do not apply to those
+sections when you distribute them as separate works. But when you
+distribute the same sections as part of a whole which is a work based
+on the Library, the distribution of the whole must be on the terms of
+this License, whose permissions for other licensees extend to the
+entire whole, and thus to each and every part regardless of who wrote
+it.
+
+Thus, it is not the intent of this section to claim rights or contest
+your rights to work written entirely by you; rather, the intent is to
+exercise the right to control the distribution of derivative or
+collective works based on the Library.
+
+In addition, mere aggregation of another work not based on the Library
+with the Library (or with a work based on the Library) on a volume of
+a storage or distribution medium does not bring the other work under
+the scope of this License.
+
+ 3. You may opt to apply the terms of the ordinary GNU General Public
+License instead of this License to a given copy of the Library. To do
+this, you must alter all the notices that refer to this License, so
+that they refer to the ordinary GNU General Public License, version 2,
+instead of to this License. (If a newer version than version 2 of the
+ordinary GNU General Public License has appeared, then you can specify
+that version instead if you wish.) Do not make any other change in
+these notices.
+
+ Once this change is made in a given copy, it is irreversible for
+that copy, so the ordinary GNU General Public License applies to all
+subsequent copies and derivative works made from that copy.
+
+ This option is useful when you wish to copy part of the code of
+the Library into a program that is not a library.
+
+ 4. You may copy and distribute the Library (or a portion or
+derivative of it, under Section 2) in object code or executable form
+under the terms of Sections 1 and 2 above provided that you accompany
+it with the complete corresponding machine-readable source code, which
+must be distributed under the terms of Sections 1 and 2 above on a
+medium customarily used for software interchange.
+
+ If distribution of object code is made by offering access to copy
+from a designated place, then offering equivalent access to copy the
+source code from the same place satisfies the requirement to
+distribute the source code, even though third parties are not
+compelled to copy the source along with the object code.
+
+ 5. A program that contains no derivative of any portion of the
+Library, but is designed to work with the Library by being compiled or
+linked with it, is called a "work that uses the Library". Such a
+work, in isolation, is not a derivative work of the Library, and
+therefore falls outside the scope of this License.
+
+ However, linking a "work that uses the Library" with the Library
+creates an executable that is a derivative of the Library (because it
+contains portions of the Library), rather than a "work that uses the
+library". The executable is therefore covered by this License.
+Section 6 states terms for distribution of such executables.
+
+ When a "work that uses the Library" uses material from a header file
+that is part of the Library, the object code for the work may be a
+derivative work of the Library even though the source code is not.
+Whether this is true is especially significant if the work can be
+linked without the Library, or if the work is itself a library. The
+threshold for this to be true is not precisely defined by law.
+
+ If such an object file uses only numerical parameters, data
+structure layouts and accessors, and small macros and small inline
+functions (ten lines or less in length), then the use of the object
+file is unrestricted, regardless of whether it is legally a derivative
+work. (Executables containing this object code plus portions of the
+Library will still fall under Section 6.)
+
+ Otherwise, if the work is a derivative of the Library, you may
+distribute the object code for the work under the terms of Section 6.
+Any executables containing that work also fall under Section 6,
+whether or not they are linked directly with the Library itself.
+
+ 6. As an exception to the Sections above, you may also combine or
+link a "work that uses the Library" with the Library to produce a
+work containing portions of the Library, and distribute that work
+under terms of your choice, provided that the terms permit
+modification of the work for the customer's own use and reverse
+engineering for debugging such modifications.
+
+ You must give prominent notice with each copy of the work that the
+Library is used in it and that the Library and its use are covered by
+this License. You must supply a copy of this License. If the work
+during execution displays copyright notices, you must include the
+copyright notice for the Library among them, as well as a reference
+directing the user to the copy of this License. Also, you must do one
+of these things:
+
+ a) Accompany the work with the complete corresponding
+ machine-readable source code for the Library including whatever
+ changes were used in the work (which must be distributed under
+ Sections 1 and 2 above); and, if the work is an executable linked
+ with the Library, with the complete machine-readable "work that
+ uses the Library", as object code and/or source code, so that the
+ user can modify the Library and then relink to produce a modified
+ executable containing the modified Library. (It is understood
+ that the user who changes the contents of definitions files in the
+ Library will not necessarily be able to recompile the application
+ to use the modified definitions.)
+
+ b) Use a suitable shared library mechanism for linking with the
+ Library. A suitable mechanism is one that (1) uses at run time a
+ copy of the library already present on the user's computer system,
+ rather than copying library functions into the executable, and (2)
+ will operate properly with a modified version of the library, if
+ the user installs one, as long as the modified version is
+ interface-compatible with the version that the work was made with.
+
+ c) Accompany the work with a written offer, valid for at
+ least three years, to give the same user the materials
+ specified in Subsection 6a, above, for a charge no more
+ than the cost of performing this distribution.
+
+ d) If distribution of the work is made by offering access to copy
+ from a designated place, offer equivalent access to copy the above
+ specified materials from the same place.
+
+ e) Verify that the user has already received a copy of these
+ materials or that you have already sent this user a copy.
+
+ For an executable, the required form of the "work that uses the
+Library" must include any data and utility programs needed for
+reproducing the executable from it. However, as a special exception,
+the materials to be distributed need not include anything that is
+normally distributed (in either source or binary form) with the major
+components (compiler, kernel, and so on) of the operating system on
+which the executable runs, unless that component itself accompanies
+the executable.
+
+ It may happen that this requirement contradicts the license
+restrictions of other proprietary libraries that do not normally
+accompany the operating system. Such a contradiction means you cannot
+use both them and the Library together in an executable that you
+distribute.
+
+ 7. You may place library facilities that are a work based on the
+Library side-by-side in a single library together with other library
+facilities not covered by this License, and distribute such a combined
+library, provided that the separate distribution of the work based on
+the Library and of the other library facilities is otherwise
+permitted, and provided that you do these two things:
+
+ a) Accompany the combined library with a copy of the same work
+ based on the Library, uncombined with any other library
+ facilities. This must be distributed under the terms of the
+ Sections above.
+
+ b) Give prominent notice with the combined library of the fact
+ that part of it is a work based on the Library, and explaining
+ where to find the accompanying uncombined form of the same work.
+
+ 8. You may not copy, modify, sublicense, link with, or distribute
+the Library except as expressly provided under this License. Any
+attempt otherwise to copy, modify, sublicense, link with, or
+distribute the Library is void, and will automatically terminate your
+rights under this License. However, parties who have received copies,
+or rights, from you under this License will not have their licenses
+terminated so long as such parties remain in full compliance.
+
+ 9. You are not required to accept this License, since you have not
+signed it. However, nothing else grants you permission to modify or
+distribute the Library or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Library (or any work based on the
+Library), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Library or works based on it.
+
+ 10. Each time you redistribute the Library (or any work based on the
+Library), the recipient automatically receives a license from the
+original licensor to copy, distribute, link with or modify the Library
+subject to these terms and conditions. You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties with
+this License.
+
+ 11. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Library at all. For example, if a patent
+license would not permit royalty-free redistribution of the Library by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Library.
+
+If any portion of this section is held invalid or unenforceable under any
+particular circumstance, the balance of the section is intended to apply,
+and the section as a whole is intended to apply in other circumstances.
+
+It is not the purpose of this section to induce you to infringe any
+patents or other property right claims or to contest validity of any
+such claims; this section has the sole purpose of protecting the
+integrity of the free software distribution system which is
+implemented by public license practices. Many people have made
+generous contributions to the wide range of software distributed
+through that system in reliance on consistent application of that
+system; it is up to the author/donor to decide if he or she is willing
+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+ 12. If the distribution and/or use of the Library is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Library under this License may add
+an explicit geographical distribution limitation excluding those countries,
+so that distribution is permitted only in or among countries not thus
+excluded. In such case, this License incorporates the limitation as if
+written in the body of this License.
+
+ 13. The Free Software Foundation may publish revised and/or new
+versions of the Lesser General Public License from time to time.
+Such new versions will be similar in spirit to the present version,
+but may differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Library
+specifies a version number of this License which applies to it and
+"any later version", you have the option of following the terms and
+conditions either of that version or of any later version published by
+the Free Software Foundation. If the Library does not specify a
+license version number, you may choose any version ever published by
+the Free Software Foundation.
+
+ 14. If you wish to incorporate parts of the Library into other free
+programs whose distribution conditions are incompatible with these,
+write to the author to ask for permission. For software which is
+copyrighted by the Free Software Foundation, write to the Free
+Software Foundation; we sometimes make exceptions for this. Our
+decision will be guided by the two goals of preserving the free status
+of all derivatives of our free software and of promoting the sharing
+and reuse of software generally.
+
+ NO WARRANTY
+
+ 15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
+WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
+EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
+OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY
+KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
+LIBRARY IS WITH YOU. SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME
+THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
+WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
+AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU
+FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
+CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
+LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
+RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
+FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Libraries
+
+ If you develop a new library, and you want it to be of the greatest
+possible use to the public, we recommend making it free software that
+everyone can redistribute and change. You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms of the
+ordinary General Public License).
+
+ To apply these terms, attach the following notices to the library. It is
+safest to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least the
+"copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ This library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the library, if
+necessary. Here is a sample; alter the names:
+
+ Yoyodyne, Inc., hereby disclaims all copyright interest in the
+ library `Frob' (a library for tweaking knobs) written by James Random Hacker.
+
+ , 1 April 1990
+ Ty Coon, President of Vice
+
+That's all there is to it!
diff --git a/README.md b/README.md
index 312fbf0..f21d190 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,13 @@
# fun_caves
-V6ish caves as a LUA mod
+
+Fun Caves is an attempt to convert the mapgen V6 caves into a lua mod, so they can be used with any mapgen. I've translated the C++ code into lua in the most mechanical way possible. I honestly have no idea how half of it works, and I don't intend to spend a lot of time on it in the future, so anyone who likes this mod is encouraged to fork and/or tinker with it and submit pull requests.
+
+
+
+The source is available on github.
+
+Code: LGPL2, textures: none
+
+Mod dependencies: default
+
+Download: https://github.com/duane-r/fun_caves/archive/master.zip
diff --git a/depends.txt b/depends.txt
new file mode 100644
index 0000000..4ad96d5
--- /dev/null
+++ b/depends.txt
@@ -0,0 +1 @@
+default
diff --git a/init.lua b/init.lua
new file mode 100644
index 0000000..c75b644
--- /dev/null
+++ b/init.lua
@@ -0,0 +1,84 @@
+fun_caves = {}
+fun_caves.version = "1.0"
+fun_caves.path = minetest.get_modpath(minetest.get_current_modname())
+fun_caves.world = false
+
+
+if fun_caves.world then
+ minetest.register_on_mapgen_init(function(mgparams)
+ minetest.set_mapgen_params({mgname="singlenode", flags="nolight"})
+ end)
+
+ if default then
+ if default.register_ores then
+ default.register_ores()
+ end
+ if default.register_blobs then
+ default.register_blobs()
+ end
+ if default.register_biomes then
+ default.register_biomes()
+ end
+ if default.register_decorations then
+ default.register_decorations()
+ end
+ if flowers.register_decorations then
+ flowers.register_decorations()
+ end
+ end
+else
+ minetest.set_mapgen_params({flags="nocaves"})
+end
+
+
+-- Modify a node to add a group
+function minetest.add_group(node, groups)
+ local def = minetest.registered_items[node]
+ if not def then
+ return false
+ end
+ local def_groups = def.groups or {}
+ for group, value in pairs(groups) do
+ if value ~= 0 then
+ def_groups[group] = value
+ else
+ def_groups[group] = nil
+ end
+ end
+ minetest.override_item(node, {groups = def_groups})
+ return true
+end
+
+function fun_caves.clone_node(name)
+ local node = minetest.registered_nodes[name]
+ local node2 = table.copy(node)
+ return node2
+end
+
+function fun_caves.node(name)
+ if not fun_caves.node_cache then
+ fun_caves.node_cache = {}
+ end
+
+ if not fun_caves.node_cache[name] then
+ fun_caves.node_cache[name] = minetest.get_content_id(name)
+ if name ~= "ignore" and fun_caves.node_cache[name] == 127 then
+ print("*** Failure to find node: "..name)
+ end
+ end
+
+ return fun_caves.node_cache[name]
+end
+
+
+--dofile(fun_caves.path .. "/nodes.lua")
+dofile(fun_caves.path .. "/mapgen.lua")
+
+
+if fun_caves.world then
+ minetest.register_on_newplayer(fun_caves.respawn)
+ minetest.register_on_respawnplayer(fun_caves.respawn)
+end
+
+-- Inserting helps to ensure that fun_caves operates first.
+table.insert(minetest.registered_on_generateds, 1, fun_caves.generate)
diff --git a/mapgen.lua b/mapgen.lua
new file mode 100644
index 0000000..8b3aa6f
--- /dev/null
+++ b/mapgen.lua
@@ -0,0 +1,520 @@
+-- Much of this code is translated directly from the Minetest
+-- cavegen.cpp, and is likewise distributed under the LGPL2.1
+
+
+local node = fun_caves.node
+
+local data = {}
+local p2data = {} -- vm rotation data buffer
+local lightmap = {}
+local vm, emin, emax, a, csize, heightmap, biomemap
+local div_sz_x, div_sz_z, minp, maxp, terrain, cave
+
+local terrain_noise = {offset = 0,
+scale = 20, seed = 8829, spread = {x = 40, y = 40, z = 40},
+octaves = 6, persist = 0.4, lacunarity = 2}
+
+local cave_noise = {offset = 0, scale = 1,
+seed = -3977, spread = {x = 30, y = 30, z = 30}, octaves = 3,
+persist = 0.8, lacunarity = 2}
+
+local seed_noise = {offset = 0, scale = 32768,
+seed = 5202, spread = {x = 80, y = 80, z = 80}, octaves = 2,
+persist = 0.4, lacunarity = 2}
+
+if fun_caves.world then
+ fun_caves.biomes = {}
+ local biomes = fun_caves.biomes
+ local biome_names = {}
+ biome_names["common"] = {}
+ biome_names["uncommon"] = {}
+ do
+ local biome_terrain_scale = {}
+ biome_terrain_scale["coniferous_forest"] = 0.75
+ biome_terrain_scale["rainforest"] = 0.33
+ biome_terrain_scale["underground"] = 1.5
+
+ local tree_biomes = {}
+ tree_biomes["deciduous_forest"] = {"deciduous_trees"}
+ tree_biomes["coniferous_forest"] = {"conifer_trees"}
+ tree_biomes["taiga"] = {"conifer_trees"}
+ tree_biomes["rainforest"] = {"jungle_trees"}
+ tree_biomes["rainforest_swamp"] = {"jungle_trees"}
+ tree_biomes["coniferous_forest"] = {"conifer_trees"}
+ tree_biomes["savanna"] = {"acacia_trees"}
+
+ for i, obiome in pairs(minetest.registered_biomes) do
+ local biome = table.copy(obiome)
+ biome.special_tree_prob = 2
+ if biome.name == "savanna" then
+ biome.special_tree_prob = 30
+ end
+ local rarity = "common"
+ biome.terrain_scale = biome_terrain_scale[biome] or 0.5
+ if string.find(biome.name, "ocean") then
+ biome.terrain_scale = 1
+ rarity = "uncommon"
+ end
+ if string.find(biome.name, "swamp") then
+ biome.terrain_scale = 0.25
+ rarity = "uncommon"
+ end
+ if string.find(biome.name, "beach") then
+ biome.terrain_scale = 0.25
+ rarity = "uncommon"
+ end
+ if string.find(biome.name, "^underground$") then
+ biome.node_top = "default:stone"
+ rarity = "uncommon"
+ end
+ biome.special_trees = tree_biomes[biome.name]
+ biomes[biome.name] = biome
+ biome_names[rarity][#biome_names[rarity]+1] = biome.name
+ end
+ end
+ biomes["control"] = {}
+end
+
+if false then
+ local cave_stones = {
+ "fun_caves:stone_with_moss",
+ "fun_caves:stone_with_lichen",
+ "fun_caves:stone_with_algae",
+ "fun_caves:stone_with_salt",
+ }
+ local mushroom_stones = {}
+ mushroom_stones[node("default:stone")] = true
+ mushroom_stones[node("fun_caves:stone_with_algae")] = true
+ mushroom_stones[node("fun_caves:stone_with_lichen")] = true
+end
+
+local function place_schematic(pos, schem, center)
+ local rot = math.random(4) - 1
+ local yslice = {}
+ if schem.yslice_prob then
+ for _, ys in pairs(schem.yslice_prob) do
+ yslice[ys.ypos] = ys.prob
+ end
+ end
+
+ if center then
+ pos.x = pos.x - math.floor(schem.size.x / 2)
+ pos.z = pos.z - math.floor(schem.size.z / 2)
+ end
+
+ for z1 = 0, schem.size.z - 1 do
+ for x1 = 0, schem.size.x - 1 do
+ local x, z
+ if rot == 0 then
+ x, z = x1, z1
+ elseif rot == 1 then
+ x, z = schem.size.z - z1 - 1, x1
+ elseif rot == 2 then
+ x, z = schem.size.x - x1 - 1, schem.size.z - z1 - 1
+ elseif rot == 3 then
+ x, z = z1, schem.size.x - x1 - 1
+ end
+ local dz = pos.z - minp.z + z
+ local dx = pos.x - minp.x + x
+ if pos.x + x > minp.x and pos.x + x < maxp.x and pos.z + z > minp.z and pos.z + z < maxp.z then
+ local ivm = a:index(pos.x + x, pos.y, pos.z + z)
+ local isch = z1 * schem.size.y * schem.size.x + x1 + 1
+ for y = 0, schem.size.y - 1 do
+ local dy = pos.y - minp.y + y
+ if math.min(dx, csize.x - dx) + math.min(dy, csize.y - dy) + math.min(dz, csize.z - dz) > bevel then
+ if yslice[y] or 255 >= math.random(255) then
+ local prob = schem.data[isch].prob or schem.data[isch].param1 or 255
+ if prob >= math.random(255) and schem.data[isch].name ~= "air" then
+ data[ivm] = node(schem.data[isch].name)
+ end
+ local param2 = schem.data[isch].param2 or 0
+ p2data[ivm] = param2
+ end
+ end
+
+ ivm = ivm + a.ystride
+ isch = isch + schem.size.x
+ end
+ end
+ end
+ end
+end
+
+local function get_decoration(biome)
+ for i, deco in pairs(fun_caves.decorations) do
+ if not deco.biomes or deco.biomes[biome] then
+ local range = 1000
+ if deco.deco_type == "simple" then
+ if deco.fill_ratio and math.random(range) - 1 < deco.fill_ratio * 1000 then
+ return deco.decoration
+ end
+ else
+ -- nop
+ end
+ end
+ end
+end
+
+
+local np_cave = {offset = 6, scale = 6, seed = 34329, spread = {x = 250, y = 250, z = 250}, octaves = 3, persist = 0.5, lacunarity = 2}
+
+local function rangelim(x, y, z)
+ return math.max(math.min(x, z), y)
+end
+
+local function carveRoute(this, vec, f, randomize_xz, tunnel_above_ground)
+ local startp = vector.new(this.orp)
+ startp = vector.add(startp, this.of)
+
+ local fp = vector.add(this.orp, vector.multiply(vec, f))
+ fp.x = fp.x + 0.1 * math.random(-10, 10)
+ fp.z = fp.z + 0.1 * math.random(-10, 10)
+ local cp = vector.new(fp)
+
+ local d0 = -this.rs/2
+ local d1 = d0 + this.rs
+ if (randomize_xz) then
+ d0 = d0 + math.random(-1, 1)
+ d1 = d1 + math.random(-1, 1)
+ end
+
+ for z0 = d0, d1 do
+ local si = this.rs / 2 - math.max(0, math.abs(z0) - this.rs / 7 - 1)
+ for x0 = -si - math.random(0,1), si - 1 + math.random(0,1) do
+ if (tunnel_above_ground) then
+ --continue
+ else
+ local maxabsxz = math.max(math.abs(x0), math.abs(z0))
+ local si2 = this.rs / 2 - math.max(0, maxabsxz - this.rs / 7 - 1)
+ for y0 = -si2, si2 do
+ if (this.large_cave_is_flat) then
+ -- Make large caves not so tall
+ if (this.rs > 7 and math.abs(y0) >= this.rs / 3) then
+ --continue
+ else
+ local p = vector.new(cp.x + x0, cp.y + y0, cp.z + z0)
+ p = vector.add(p, this.of)
+
+ if not a:containsp(p) then
+ --continue
+ else
+ local i = a:indexp(vector.round(p))
+ local c = data[i]
+ --if (not ndef.get(c).is_ground_content) then
+ -- ** check for ground content? **
+ if false then
+ --continue
+ else
+ if (this.large_cave) then
+ local full_ymin = minp.y - 16
+ local full_ymax = maxp.y + 16
+
+ if (this.flooded and full_ymin < this.water_level and full_ymax > this.water_level) then
+ data[i] = (p.y <= this.water_level) and node("default:water_source") or node("air")
+ elseif (this.flooded and full_ymax < this.water_level) then
+ data[i] = (p.y < startp.y - 2) and node("default:lava_source") or node("air")
+ else
+ data[i] = node("air")
+ end
+ else
+ if (c == node("ignore") or c == node("air")) then
+ --continue
+ else
+ data[i] = node("air")
+ end
+ end
+ end
+ end
+ end
+ end
+ end
+ end
+ end
+ end
+end
+
+local function makeTunnel(this, dirswitch)
+ if dirswitch and not this.large_cave then
+ this.main_direction = vector.new(
+ ((math.random() * 20) - 10) / 10,
+ ((math.random() * 20) - 10) / 30,
+ ((math.random() * 20) - 10) / 10
+ )
+ this.main_direction = vector.multiply(this.main_direction, math.random(0, 10) / 10)
+ end
+
+ -- Randomize size
+ local min_d = this.min_tunnel_diameter
+ local max_d = this.max_tunnel_diameter
+ this.rs = math.random(min_d, max_d)
+ local rs_part_max_length_rs = this.rs * this.part_max_length_rs
+
+ local maxlen
+ if this.large_cave then
+ maxlen = vector.new(
+ rs_part_max_length_rs,
+ rs_part_max_length_rs / 2,
+ rs_part_max_length_rs
+ )
+ else
+ maxlen = vector.new(
+ rs_part_max_length_rs,
+ math.random(1, rs_part_max_length_rs),
+ rs_part_max_length_rs
+ )
+ end
+
+ local vec = vector.new(
+ (math.random() * maxlen.x) - maxlen.x / 2,
+ (math.random() * maxlen.y) - maxlen.y / 2,
+ (math.random() * maxlen.z) - maxlen.z / 2
+ )
+
+ -- Jump downward sometimes
+ if not this.large_cave and math.random(0, 12) == 0 then
+ vec = vector.new(
+ (math.random() * maxlen.x) - maxlen.x / 2,
+ (math.random() * (maxlen.y * 2)) - maxlen.y,
+ (math.random() * maxlen.z) - maxlen.z / 2
+ )
+ end
+
+ -- Do not make caves that are entirely above ground, to fix
+ -- shadow bugs caused by overgenerated large caves.
+ -- It is only necessary to check the startpoint and endpoint.
+ local orpi = vector.new(this.orp.x, this.orp.y, this.orp.z)
+ local veci = vector.new(vec.x, vec.y, vec.z)
+ local h1
+ local h2
+
+ local p1 = vector.add(orpi, veci, this.of, this.rs / 2)
+ if (p1.z >= minp.z and p1.z <= maxp.z and
+ p1.x >= minp.x and p1.x <= maxp.x) then
+ local index1 = (p1.z - minp.z) * mg.ystride + (p1.x - minp.x)
+ --h1 = mg.heightmap[index1]
+ h1 = this.water_level
+ else
+ h1 = this.water_level -- If not in heightmap
+ end
+
+ local p2 = vector.add(orpi, this.of, this.rs / 2)
+ if (p2.z >= minp.z and p2.z <= maxp.z and
+ p2.x >= minp.x and p2.x <= maxp.x) then
+ local index2 = (p2.z - minp.z) * a.ystride + (p2.x - minp.x)
+ --h2 = mg.heightmap[index2]
+ h2 = this.water_level
+ else
+ h2 = this.water_level
+ end
+
+ -- If startpoint and endpoint are above ground,
+ -- disable placing of nodes in carveRoute while
+ -- still running all pseudorandom calls to ensure
+ -- caves consistent with existing worlds.
+ local tunnel_above_ground = p1.y > h1 and p2.y > h2
+
+ vec = vector.add(vec, this.main_direction)
+
+ local rp = vector.add(this.orp, vec)
+ if (rp.x < 0) then
+ rp.x = 0
+ elseif (rp.x >= this.ar.x) then
+ rp.x = this.ar.x - 1
+ end
+
+ if (rp.y < this.route_y_min) then
+ rp.y = this.route_y_min
+ elseif (rp.y >= this.route_y_max) then
+ rp.y = this.route_y_max - 1
+ end
+
+ if (rp.z < 0) then
+ rp.z = 0
+ elseif (rp.z >= this.ar.z) then
+ rp.z = this.ar.z - 1
+ end
+
+ vec = vector.subtract(rp, this.orp)
+
+ local veclen = vector.length(vec)
+ -- As odd as it sounds, veclen is *exactly* 0.0 sometimes, causing a FPE
+ if (veclen < 0.05) then
+ veclen = 1.0
+ end
+
+ -- Every second section is rough
+ local randomize_xz = (math.random(1, 2) == 1)
+
+ -- Carve routes
+ for f = 0, 1, 1.0 / veclen do
+ --print(dump(vec))
+ carveRoute(this, vec, f, randomize_xz, tunnel_above_ground)
+ end
+
+ this.orp = rp
+end
+
+local function makeCave(this, max_stone_height)
+ this.max_stone_y = max_stone_height
+ this.main_direction = vector.new(0, 0, 0)
+ --print(dump(this))
+
+ -- Allowed route area size in nodes
+ this.ar = vector.add(vector.subtract(maxp, minp), 1)
+ -- Area starting point in nodes
+ this.of = minp
+
+ -- Allow a bit more
+ --(this should be more than the maximum radius of the tunnel)
+ local max_spread_amount = 16
+ local insure = 10
+ local more = math.max(max_spread_amount - this.max_tunnel_diameter / 2 - insure, 1)
+ this.ar = vector.add(this.ar, vector.multiply(vector.new(1,0,1), (more * 2)))
+ this.of = vector.subtract(this.of, vector.multiply(vector.new(1,0,1), more))
+
+ this.route_y_min = 0
+ -- Allow half a diameter + 7 over stone surface
+ this.route_y_max = -this.of.y + this.max_stone_y + this.max_tunnel_diameter / 2 + 7
+
+ -- Limit maximum to area
+ this.route_y_max = rangelim(this.route_y_max, 0, this.ar.y - 1)
+
+ if this.large_cave then
+ local min = 0
+ if minp.y < this.water_level and maxp.y > this.water_level then
+ min = this.water_level - this.max_tunnel_diameter/3 - this.of.y
+ this.route_y_max = this.water_level + this.max_tunnel_diameter/3 - this.of.y
+ end
+ this.route_y_min = math.random(min, min + this.max_tunnel_diameter)
+ this.route_y_min = rangelim(this.route_y_min, 0, this.route_y_max)
+ end
+
+ local route_start_y_min = this.route_y_min
+ local route_start_y_max = this.route_y_max
+
+ route_start_y_min = rangelim(route_start_y_min, 0, this.ar.y-1)
+ route_start_y_max = rangelim(route_start_y_max, route_start_y_min, this.ar.y-1)
+
+ -- Randomize starting position
+ this.orp = vector.new(
+ (math.random() * this.ar.x) + 0.5,
+ (math.random(route_start_y_min, route_start_y_max)) + 0.5,
+ (math.random() * this.ar.z) + 0.5
+ )
+
+ -- Generate some tunnel starting from orp
+ for j = 0, this.tunnel_routepoints do
+ --print(dump(this.orp))
+ makeTunnel(this, j % this.dswitchint == 0)
+ end
+end
+
+local function CaveV6(is_large_cave)
+ local this = {}
+ this.water_level = 1
+ this.large_cave = is_large_cave
+
+ this.min_tunnel_diameter = 2
+ this.max_tunnel_diameter = math.random(2, 6)
+ this.dswitchint = math.random(1, 14)
+ this.flooded = true
+
+ if this.large_cave then
+ this.part_max_length_rs = math.random(2,4)
+ this.tunnel_routepoints = math.random(5, math.random(15,30))
+ this.min_tunnel_diameter = 5
+ this.max_tunnel_diameter = math.random(7, math.random(8,24))
+ else
+ this.part_max_length_rs = math.random(2,9)
+ this.tunnel_routepoints = math.random(10, math.random(15,30))
+ end
+
+ this.large_cave_is_flat = (math.random(0,1) == 0)
+ return this
+end
+
+local function getBiome(x, z)
+ return nil
+end
+
+local function generateCaves(max_stone_y)
+ local cave_amount = minetest.get_perlin(np_cave):get2d({x=minp.x, y=minp.y})
+ local volume_nodes = (maxp.x - minp.x + 1) * (maxp.y - minp.y + 1) * 16
+ cave_amount = math.max(0.0, cave_amount)
+ local caves_count = cave_amount * volume_nodes / 50000
+ local bruises_count = 1
+
+ if (math.random(1, 6) == 1) then
+ bruises_count = math.random(0, math.random(0, 2))
+ end
+
+ if (getBiome(minp.x, minp.z) == "desert") then
+ caves_count = caves_count / 3
+ bruises_count = caves_count / 3
+ end
+
+ for i = 0, caves_count + bruises_count do
+ local large_cave = (i >= caves_count)
+ local cave = CaveV6(large_cave)
+
+ --print(dump(cave))
+ makeCave(cave, max_stone_y)
+ end
+end
+
+
+function fun_caves.generate(p_minp, p_maxp, seed)
+ minp, maxp = p_minp, p_maxp
+ vm, emin, emax = minetest.get_mapgen_object("voxelmanip")
+ vm:get_data(data)
+ --p2data = vm:get_param2_data()
+ a = VoxelArea:new({MinEdge = emin, MaxEdge = emax})
+ csize = vector.add(vector.subtract(maxp, minp), 1)
+
+ -- Deal with memory issues. This, of course, is supposed to be automatic.
+ local mem = math.floor(collectgarbage("count")/1024)
+ if mem > 400 then
+ print("Fun Caves: Manually collecting garbage...")
+ collectgarbage("collect")
+ end
+
+ -- use the same seed (based on perlin noise).
+ math.randomseed(minetest.get_perlin(seed_noise):get2d({x=minp.x, y=minp.z}))
+
+ -- Keep this first after seeding!
+ local px = math.floor((minp.x + 32) / csize.x)
+ local pz = math.floor((minp.z + 32) / csize.z)
+
+ generateCaves(1)
+
+ --local index = 0
+ --local index3d = 0
+ --for z = minp.z, maxp.z do
+ -- local dz = z - minp.z
+ -- for x = minp.x, maxp.x do
+ -- index = index + 1
+ -- local dx = x - minp.x
+ -- index3d = dz * csize.y * csize.x + dx + 1
+ -- local ivm = a:index(x, minp.y, z)
+
+ -- for y = minp.y, maxp.y do
+ -- local dy = y - minp.y
+
+ -- ivm = ivm + a.ystride
+ -- index3d = index3d + csize.x
+ -- end
+ -- end
+ --end
+
+
+ vm:set_data(data)
+ --minetest.generate_ores(vm, minp, maxp)
+ --minetest.generate_decorations(vm, minp, maxp)
+ --vm:set_param2_data(p2data)
+ vm:set_lighting({day = 15, night = 15})
+ vm:update_liquids()
+ vm:calc_lighting(minp, maxp, false)
+ vm:write_to_map()
+
+ vm, a, lightmap, heightmap, biomemap, terrain, cave = nil, nil, nil, nil, nil, nil, nil
+end
diff --git a/mod.conf b/mod.conf
new file mode 100644
index 0000000..d3d10d4
--- /dev/null
+++ b/mod.conf
@@ -0,0 +1 @@
+name = fun_caves
diff --git a/textures/screenshot.jpg b/textures/screenshot.jpg
new file mode 100644
index 0000000..fed3e87
Binary files /dev/null and b/textures/screenshot.jpg differ