Vulkan® 1.4.326 - A Specification (with all registered extensions)

1. Preamble

This Specification is protected by copyright laws and contains material proprietary to Khronos. Except as described by these terms, it or any components may not be reproduced, republished, distributed, transmitted, displayed, broadcast or otherwise exploited in any manner without the express prior written permission of Khronos.

Khronos grants a conditional copyright license to use and reproduce the unmodified Specification for any purpose, without fee or royalty, EXCEPT no licenses to any patent, trademark or other intellectual property rights are granted under these terms.

Khronos makes no, and expressly disclaims any, representations or warranties, express or implied, regarding this Specification, including, without limitation: merchantability, fitness for a particular purpose, non-infringement of any intellectual property, correctness, accuracy, completeness, timeliness, and reliability. Under no circumstances will Khronos, or any of its Promoters, Contributors or Members, or their respective partners, officers, directors, employees, agents or representatives be liable for any damages, whether direct, indirect, special or consequential damages for lost revenues, lost profits, or otherwise, arising from or in connection with these materials.

This document contains extensions which are not ratified by Khronos, and as such is not a ratified Specification, though it contains text from (and is a superset of) the ratified Specification.

The ratified version of the Vulkan Specification can be found at https://registry.khronos.org/vulkan/specs/latest-ratified/pdf/vkspec.pdf (core with all ratified extensions).

This Specification contains substantially unmodified functionality from, and is a successor to, Khronos specifications including OpenGL, OpenGL ES and OpenCL.

The Khronos Intellectual Property Rights Policy defines the terms 'Scope', 'Compliant Portion', and 'Necessary Patent Claims'.

Some parts of this Specification are purely informative and so are EXCLUDED the Scope of this Specification. The Document Conventions section of the Introduction defines how these parts of the Specification are identified.

Where this Specification uses technical terminology, defined in the Glossary or otherwise, that refer to enabling technologies that are not expressly set forth in this Specification, those enabling technologies are EXCLUDED from the Scope of this Specification. For clarity, enabling technologies not disclosed with particularity in this Specification (e.g. semiconductor manufacturing technology, hardware architecture, processor architecture or microarchitecture, memory architecture, compiler technology, object oriented technology, basic operating system technology, compression technology, algorithms, and so on) are NOT to be considered expressly set forth; only those application program interfaces and data structures disclosed with particularity are included in the Scope of this Specification.

For purposes of the Khronos Intellectual Property Rights Policy as it relates to the definition of Necessary Patent Claims, all recommended or optional features, behaviors and functionality set forth in this Specification, if implemented, are considered to be included as Compliant Portions.

Where this Specification identifies specific sections of external references, only those specifically identified sections define normative functionality. The Khronos Intellectual Property Rights Policy excludes external references to materials and associated enabling technology not created by Khronos from the Scope of this Specification, and any licenses that may be required to implement such referenced materials and associated technologies must be obtained separately and may involve royalty payments.

Khronos and Vulkan are registered trademarks, and SPIR-V is a trademark of The Khronos Group Inc. OpenCL is a trademark of Apple Inc., used under license by Khronos. OpenGL is a registered trademark and the OpenGL ES logo is a trademark of Hewlett Packard Enterprise, used under license by Khronos. ASTC is a trademark of ARM Holdings PLC. All other product names, trademarks, and/or company names are used solely for identification and belong to their respective owners.

2. Introduction

This document, referred to as the “Vulkan Specification” or just the “Specification” hereafter, describes the Vulkan Application Programming Interface (API). Vulkan is a C99 API designed for explicit control of low-level graphics and compute functionality.

The canonical version of the Specification is available in the official Vulkan Registry (https://registry.khronos.org/vulkan/). The source files used to generate the Vulkan specification are stored in the Vulkan Documentation Repository (https://github.com/KhronosGroup/Vulkan-Docs).

The source repository additionally has a public issue tracker and allows the submission of pull requests that improve the specification.

2.1. Document Conventions

The Vulkan specification is intended for use by both implementors of the API and application developers seeking to make use of the API, forming a contract between these parties. Specification text may address either party; typically the intended audience can be inferred from context, though some sections are defined to address only one of these parties. (For example, Valid Usage sections only address application developers). Any requirements, prohibitions, recommendations or options defined in specification text are imposed only on the audience of that text.

2.1.1. Normative Requirements

The Vulkan Specification uses a combination of normative terminology and normative descriptions to express the requirements that it imposes on applications and implementations. An application which complies with all normative requirements imposed on applications is said to make valid use of the API; failing to comply with such requirements results in undefined behavior, as discussed in the Valid Usage section below. In the context of this document, an implementation which complies with all normative requirements imposed on implementations is said to be conformant.

Note

The Khronos Group imposes additional requirements on implementors who wish to make public statements describing their Vulkan implementations as conformant. These include signing the Vulkan Adopter’s Agreement, paying the associated fee, and making a successful conformance test submission to the Khronos Conformance Process. For details see the