x-end: refine integration with MK3 idler tensioner

[clinton/prusa3.git] / LICENSE.md

GNU GENERAL PUBLIC LICENSE
==========================

Version 3, 29 June 2007

Copyright &copy; 2007 Free Software Foundation, Inc. &lt;<http://fsf.org/>&gt;

Everyone is permitted to copy and distribute verbatim copies of this license
document, but changing it is not allowed.

## Preamble

The GNU General Public License is a free, copyleft license for software and other
kinds of works.

The licenses for most software and other practical works are designed to take away
your freedom to share and change the works. By contrast, the GNU General Public
License is intended to guarantee your freedom to share and change all versions of a
program--to make sure it remains free software for all its users. We, the Free
Software Foundation, use the GNU General Public License for most of our software; it
applies also to any other work released this way by its authors. You can apply it to
your programs, too.

When we speak of free software, we are referring to freedom, 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 them if you wish), that you receive source
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To protect your rights, we need to prevent others from denying you these rights or
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For example, if you distribute copies of such a program, whether gratis or for a fee,
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Developers that use the GNU GPL protect your rights with two steps: (1) assert
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The precise terms and conditions for copying, distribution and modification follow.

## TERMS AND CONDITIONS

### 0. Definitions.

&ldquo;This License&rdquo; refers to version 3 of the GNU General Public License.

&ldquo;Copyright&rdquo; also means copyright-like laws that apply to other kinds of
works, such as semiconductor masks.

&ldquo;The Program&rdquo; refers to any copyrightable work licensed under this
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To &ldquo;modify&rdquo; a work means to copy from or adapt all or part of the work in
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A &ldquo;covered work&rdquo; means either the unmodified Program or a work based on
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To &ldquo;propagate&rdquo; a work means to do anything with it that, without
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To &ldquo;convey&rdquo; a work means any kind of propagation that enables other
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An interactive user interface displays &ldquo;Appropriate Legal Notices&rdquo; to the
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### 1. Source Code.

The &ldquo;source code&rdquo; for a work means the preferred form of the work for
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A &ldquo;Standard Interface&rdquo; means an interface that either is an official
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A &ldquo;Major Component&rdquo;, in this context, means a major essential component
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The &ldquo;Corresponding Source&rdquo; for a work in object code form means all the
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The Corresponding Source need not include anything that users can regenerate
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The Corresponding Source for a work in source code form is that same work.

### 2. Basic Permissions.

All rights granted under this License are granted for the term of copyright on the
Program, and are irrevocable provided the stated conditions are met. This License
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You may make, run and propagate covered works that you do not convey, without
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works to others for the sole purpose of having them make modifications exclusively
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Conveying under any other circumstances is permitted solely under the conditions
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### 3. Protecting Users' Legal Rights From Anti-Circumvention Law.

No covered work shall be deemed part of an effective technological measure under any
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adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention
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When you convey a covered work, you waive any legal power to forbid circumvention of
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intention to limit operation or modification of the work as a means of enforcing,
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### 4. Conveying Verbatim Copies.

You may convey verbatim copies of the Program's source code as you receive it, in any
medium, provided that you conspicuously and appropriately publish on each copy an
appropriate copyright notice; keep intact all notices stating that this License and
any non-permissive terms added in accord with section 7 apply to the code; keep
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You may charge any price or no price for each copy that you convey, and you may offer
support or warranty protection for a fee.

### 5. Conveying Modified Source Versions.

You may convey a work based on the Program, or the modifications to produce it from
the Program, in the form of source code under the terms of section 4, provided that
you also meet all of these conditions:

* a) The work must carry prominent notices stating that you modified it, and giving a
relevant date.
* b) The work must carry prominent notices stating that it is released under this
License and any conditions added under section 7. This requirement modifies the
requirement in section 4 to &ldquo;keep intact all notices&rdquo;.
* c) You must license the entire work, as a whole, under this License to anyone who
comes into possession of a copy. This License will therefore apply, along with any
applicable section 7 additional terms, to the whole of the work, and all its parts,
regardless of how they are packaged. This License gives no permission to license the
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separately received it.
* d) If the work has interactive user interfaces, each must display Appropriate Legal
Notices; however, if the Program has interactive interfaces that do not display
Appropriate Legal Notices, your work need not make them do so.

A compilation of a covered work with other separate and independent works, which are
not by their nature extensions of the covered work, and which are not combined with
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medium, is called an &ldquo;aggregate&rdquo; if the compilation and its resulting
copyright are not used to limit the access or legal rights of the compilation's users
beyond what the individual works permit. Inclusion of a covered work in an aggregate
does not cause this License to apply to the other parts of the aggregate.

### 6. Conveying Non-Source Forms.

You may convey a covered work in object code form under the terms of sections 4 and
5, provided that you also convey the machine-readable Corresponding Source under the
terms of this License, in one of these ways:

* a) Convey the object code in, or embodied in, a physical product (including a
physical distribution medium), accompanied by the Corresponding Source fixed on a
durable physical medium customarily used for software interchange.
* b) Convey the object code in, or embodied in, a physical product (including a
physical distribution medium), accompanied by a written offer, valid for at least
three years and valid for as long as you offer spare parts or customer support for
that product model, to give anyone who possesses the object code either (1) a copy of
the Corresponding Source for all the software in the product that is covered by this
License, on a durable physical medium customarily used for software interchange, for
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* c) Convey individual copies of the object code with a copy of the written offer to
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accord with subsection 6b.
* d) Convey the object code by offering access from a designated place (gratis or for
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* e) Convey the object code using peer-to-peer transmission, provided you inform
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If you convey an object code work under this section in, or with, or specifically for
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The requirement to provide Installation Information does not include a requirement to
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Corresponding Source conveyed, and Installation Information provided, in accord with
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### 7. Additional Terms.

&ldquo;Additional permissions&rdquo; are terms that supplement the terms of this
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permissions that are applicable to the entire Program shall be treated as though they
were included in this License, to the extent that they are valid under applicable
law. If additional permissions apply only to part of the Program, that part may be
used separately under those permissions, but the entire Program remains governed by
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When you convey a copy of a covered work, you may at your option remove any
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Notwithstanding any other provision of this License, for material you add to a
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* a) Disclaiming warranty or limiting liability differently from the terms of
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* b) Requiring preservation of specified reasonable legal notices or author
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All other non-permissive additional terms are considered &ldquo;further
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If you add terms to a covered work in accord with this section, you must place, in
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Additional terms, permissive or non-permissive, may be stated in the form of a
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### 8. Termination.

You may not propagate or modify a covered work except as expressly provided under
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granted under the third paragraph of section 11).

However, if you cease all violation of this License, then your license from a
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copyright holder explicitly and finally terminates your license, and (b) permanently,
if the copyright holder fails to notify you of the violation by some reasonable means
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Moreover, your license from a particular copyright holder is reinstated permanently
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is the first time you have received notice of violation of this License (for any
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Termination of your rights under this section does not terminate the licenses of
parties who have received copies or rights from you under this License. If your
rights have been terminated and not permanently reinstated, you do not qualify to
receive new licenses for the same material under section 10.

### 9. Acceptance Not Required for Having Copies.

You are not required to accept this License in order to receive or run a copy of the
Program. Ancillary propagation of a covered work occurring solely as a consequence of
using peer-to-peer transmission to receive a copy likewise does not require
acceptance. However, nothing other than this License grants you permission to
propagate or modify any covered work. These actions infringe copyright if you do not
accept this License. Therefore, by modifying or propagating a covered work, you
indicate your acceptance of this License to do so.

### 10. Automatic Licensing of Downstream Recipients.

Each time you convey a covered work, the recipient automatically receives a license
from the original licensors, to run, modify and propagate that work, subject to this
License. You are not responsible for enforcing compliance by third parties with this
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An &ldquo;entity transaction&rdquo; is a transaction transferring control of an
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You may not impose any further restrictions on the exercise of the rights granted or
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initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging
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### 11. Patents.

A &ldquo;contributor&rdquo; is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based. The work thus
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A contributor's &ldquo;essential patent claims&rdquo; are all patent claims owned or
controlled by the contributor, whether already acquired or hereafter acquired, that
would be infringed by some manner, permitted by this License, of making, using, or
selling its contributor version, but do not include claims that would be infringed
only as a consequence of further modification of the contributor version. For
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sublicenses in a manner consistent with the requirements of this License.

Each contributor grants you a non-exclusive, worldwide, royalty-free patent license
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In the following three paragraphs, a &ldquo;patent license&rdquo; is any express
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If you convey a covered work, knowingly relying on a patent license, and the
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Source to be so available, or (2) arrange to deprive yourself of the benefit of the
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the requirements of this License, to extend the patent license to downstream
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A patent license is &ldquo;discriminatory&rdquo; if it does not include within the
scope of its coverage, prohibits the exercise of, or is conditioned on the
non-exercise of one or more of the rights that are specifically granted under this
License. You may not convey a covered work if you are a party to an arrangement with
a third party that is in the business of distributing software, under which you make
payment to the third party based on the extent of your activity of conveying the
work, and under which the third party grants, to any of the parties who would receive
the covered work from you, a discriminatory patent license (a) in connection with
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primarily for and in connection with specific products or compilations that contain
the covered work, unless you entered into that arrangement, or that patent license
was granted, prior to 28 March 2007.

Nothing in this License shall be construed as excluding or limiting any implied
license or other defenses to infringement that may otherwise be available to you
under applicable patent law.

### 12. No Surrender of Others' Freedom.

If 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 convey a covered work so as to satisfy
simultaneously your obligations under this License and any other pertinent
obligations, then as a consequence you may not convey it at all. For example, if you
agree to terms that obligate you to collect a royalty for further conveying from
those to whom you convey the Program, the only way you could satisfy both those terms
and this License would be to refrain entirely from conveying the Program.

### 13. Use with the GNU Affero General Public License.

Notwithstanding any other provision of this License, you have permission to link or
combine any covered work with a work licensed under version 3 of the GNU Affero
General Public License into a single combined work, and to convey the resulting work.
The terms of this License will continue to apply to the part which is the covered
work, but the special requirements of the GNU Affero General Public License, section
13, concerning interaction through a network will apply to the combination as such.

### 14. Revised Versions of this License.

The Free Software Foundation may publish revised and/or new versions of the GNU
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 Program specifies that
a certain numbered version of the GNU General Public License &ldquo;or any later
version&rdquo; applies to it, you have the option of following the terms and
conditions either of that numbered version or of any later version published by the
Free Software Foundation. If the Program does not specify a version number of the GNU
General Public License, you may choose any version ever published by the Free
Software Foundation.

If the Program specifies that a proxy can decide which future versions of the GNU
General Public License can be used, that proxy's public statement of acceptance of a
version permanently authorizes you to choose that version for the Program.

Later license versions may give you additional or different permissions. However, no
additional obligations are imposed on any author or copyright holder as a result of
your choosing to follow a later version.

### 15. Disclaimer of Warranty.

THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
PROVIDE THE PROGRAM &ldquo;AS IS&rdquo; 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 PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE
DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

### 16. Limitation of Liability.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY
COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM 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
PROGRAM (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 PROGRAM TO OPERATE
WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.

### 17. Interpretation of Sections 15 and 16.

If the disclaimer of warranty and limitation of liability provided above cannot be
given local legal effect according to their terms, reviewing courts shall apply local
law that most closely approximates an absolute waiver of all civil liability in
connection with the Program, unless a warranty or assumption of liability accompanies
a copy of the Program in return for a fee.