1  COPYING.md for the KhronosGroup/Vulkan-Docs project
 2  ===================================================
 3  
 4  # Licenses
 5  
 6  The Vulkan-Docs project uses several licenses.
 7  
 8  * The source files (in asciidoctor and other formats) for the Vulkan
 9    Specification, reference pages, and supporting documentation are licensed
10    under the Creative Commons Attribution 4.0 International License
11    ("CC-BY").
12  * Header files, scripts, programs, XML files, and other tooling used or
13    generated as part of the build process is licensed under the Apache
14    License, Version 2.0.
15  * There are a few remaining configuration files and scripts adopted from
16    other open source projects, such as the 'optimize-pdf' script. Such files
17    continue under their original copyrights.
18  * Some generated, transient files produced during the course of building the
19    specification, headers, or other targets may not have copyrights. These
20    are typically very short asciidoc fragments describing parts of the Vulkan
21    API, and are incorporated by reference into specification or reference
22    page builds.
23  
24  Users outside Khronos who create and post Vulkan Specifications, whether
25  modified or not, should use the CC-BY license on the output documents (HTML,
26  PDF, etc.) they generate.
27  
28  
29  # Frequently Asked Questions
30  
31  Q: Why are the HTML and PDF Specifications posted on Khronos' website under
32  a license which is neither CC-BY nor Apache 2.0?
33  
34  A: The Specifications posted by Khronos in the Vulkan Registry are licensed
35  under the proprietary Khronos Specification License. Only these
36  Specifications are Ratified by the Khronos Board of Promoters, and therefore
37  they are the only Specifications covered by the Khronos Intellectual
38  Property Rights Policy.
39  
40  
41  Q: Does Khronos allow the creation and distribution of modified versions of
42  the Vulkan Specification, such as translations to other languages?
43  
44  A: Yes. Such modified Specifications, since they are not created by Khronos,
45  should be placed under the CC-BY license. If you believe your modifications
46  are of general interest, consider contributing them back by making a pull
47  request (PR) on the Vulkan-Docs project.
48  
49  
50  Q: Can I contribute changes to the Vulkan Specification?
51  
52  A: Yes, by opening a PR on the KhronosGroup/Vulkan-Docs Github project. You
53  must execute a click-through Contributor License Agreement, which brings
54  your changes under the umbrella of the Khronos IP policy. We welcome
55  feedback and proposed changes, but will not necessarily accept all such
56  changes. Please keep PRs focused on solving a single problem; more ambitious
57  PRs that try to solve multiple problems, or touch many parts of the
58  Specification at once, are difficult for the Vulkan Working Group to review
59  in a timely fashion.
60  
61  
62  Q: Can you change the license on your files so they're compatible with my
63  license?
64  
65  A: We've added an "Exceptions to the Apache 2.0 License" clause to the
66  copyright on vk.xml, to make it more compatible with GPL-licensed software,
67  such as externally-generated language bindings. This seems to have addressed
68  the problems we're aware of. It is possible we could extend the Exception
69  Clause to other Apache-licensed files in the project, or otherwise
70  accommodate new needs of external projects; but working with the different
71  Khronos member company IP lawyers to make license changes is a very slow
72  process, constrained by the Khronos Member Agreement and IP Policy as well
73  as by individual company concerns about their IP. Do not expect rapid
74  changes in anything having to do with copyrights and licensing.