| // Copyright 2020-2023 The Khronos Group Inc. |
| // SPDX-License-Identifier: CC-BY-4.0 |
| |
| = COPYING File for the KhronosGroup/Vulkan-Docs Project |
| |
| == Licenses |
| |
| The Vulkan-Docs project uses several licenses. |
| |
| * The source files (in asciidoctor and other formats) for the Vulkan |
| Specification, reference pages, and supporting documentation are licensed |
| under the Creative Commons Attribution 4.0 International License (SPDX |
| license identifier "`CC-BY-4.0`"). |
| * Header files, scripts, programs, XML files, and other tooling used or |
| generated as part of the build process are typically licensed under the |
| Apache License, Version 2.0 (SPDX license identifier "`Apache-2.0`"). |
| * For compatibility with external developers working in GPLed projects who |
| have requested it, link:xml/vk.xml[`vk.xml`] and |
| link:xml/video.xml[`video.xml`] are licensed under a dual (SPDX license |
| identifier "`Apache-2.0 OR MIT`" License). |
| * Fonts derived from the M+ Font Project, found in |
| link:config/fonts/[`config/fonts/`] are licensed under the M+ Font License |
| (SPDX license identifier "`LicenseRef-MPLUS`"). This is an open source |
| license but is not OSI-approved, and is found at |
| https://osdn.net/softwaremap/trove_list.php?form_cat=370 |
| * Code which converts the single-file HTML specification to a chunked |
| HTML document, kept in |
| link:scripts/asciidoctor-chunker[`scripts/asciidoctor-chunker`], is |
| licensed under the MIT license. The home of the |
| link:https://github.com/wshito/asciidoctor-chunker[chunker project] is |
| found on GitHub. |
| * There are a few remaining files adopted from other open source projects, |
| such as a copy of the KaTeX distribution. Such files continue under their |
| original MIT licenses, or in a few cases, like |
| link:scripts/htmldiff/htmldiff[`scripts/htmldiff/htmldiff`], had no |
| license statement. We have not added SPDX license identifiers to such |
| externally originated files. |
| * Some generated, transient files produced during the course of building the |
| specification, headers, or other targets may not have copyrights. These |
| are typically very short asciidoc fragments describing parts of the Vulkan |
| API, and are incorporated by reference into specification or reference |
| page builds. |
| |
| Users outside Khronos who create and post Vulkan Specifications, whether |
| modified or not, should use the CC-BY-4.0 license on the *output* documents |
| (HTML, PDF, etc.) they generate. This is the default when building the |
| Specification. |
| |
| |
| == Frequently Asked Questions |
| |
| Q: Why are the HTML and PDF Specifications posted on Khronos' website under |
| a license which is neither CC-BY nor Apache-2.0? |
| |
| A: The Specifications posted by Khronos in the Vulkan Registry are licensed |
| under the proprietary Khronos Specification License. Only these |
| Specifications are Ratified by the Khronos Board of Promoters, and therefore |
| they are the only Specifications covered by the Khronos Intellectual |
| Property Rights Policy. |
| |
| |
| Q: Does Khronos allow the creation and distribution of modified versions of |
| the Vulkan Specification, such as translations to other languages? |
| |
| A: Yes. Such modified Specifications, since they are not created by Khronos, |
| should be placed under the CC-BY license. If you believe your modifications |
| are of general interest, consider contributing them back by making a pull |
| request (PR) on the Vulkan-Docs project. |
| |
| |
| Q: Can I contribute changes to the Vulkan Specification? |
| |
| A: Yes, by opening an Issue or Pull Request (PR) on the |
| link:https://github.com/KhronosGroup/Vulkan-Docs/[Vulkan-Docs] GitHub |
| project. |
| You must execute a click-through Contributor License Agreement, which brings |
| your changes under the umbrella of the Khronos IP policy. |
| |
| |
| Q: Can you change the license on your files so they are compatible with my |
| license? |
| |
| A: We are using a dual license on `vk.xml` and `video.xml`, to make them |
| compatible with GPL-licensed projects such as externally-generated language |
| bindings. |
| This replaces an earlier Apache 2.0 + "Exception Clause" license on the file |
| with a more standard methodology, and allows use of the SPDX license |
| identifier "`Apache-2.0 OR MIT`" to denote the license. |
| |
| If you *require* GPL compatibility for use of other Apache-2.0 licensed |
| files in our repository, please raise an issue identifying the files and we |
| will consider changing those specific files to the dual license as well. |
| |
