Registered Extension Number




Ratification Status

Not ratified

Extension and Version Dependencies

Deprecation state


Other Extension Metadata

Last Modified Date


IP Status

No known IP claims.

  • Matthaeus G. Chajdas, AMD

  • Graham Sellers, AMD

  • Baldur Karlsson


This extension allows an application to specify a negative viewport height. The result is that the viewport transformation will flip along the y-axis.

  • Allow negative height to be specified in the VkViewport::height field to perform y-inversion of the clip-space to framebuffer-space transform. This allows apps to avoid having to use gl_Position.y = -gl_Position.y in shaders also targeting other APIs.

Obsoletion by VK_KHR_maintenance1 and Vulkan 1.1

Functionality in this extension is included in VK_KHR_maintenance1 and subsequently Vulkan 1.1. Due to some slight behavioral differences, this extension must not be enabled alongside VK_KHR_maintenance1, or in an instance created with version 1.1 or later requested in VkApplicationInfo::apiVersion.

New Enum Constants



Version History

  • Revision 1, 2016-09-02 (Matthaeus Chajdas)

    • Initial draft

See Also

No cross-references are available

Document Notes

For more information, see the Vulkan Specification

This page is a generated document. Fixes and changes should be made to the generator scripts, not directly.

Copyright 2014-2023 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0