Name Strings

SPV_EXT_opacity_micromap

Contact

See Issues list in the Khronos SPIRV-Headers repository: https://github.com/KhronosGroup/SPIRV-Headers

Contributors

  • Eric Werness, NVIDIA

  • Joshua Barczak, Intel

Status

  • Complete

Version

Last Modified Date

2022-07-28

Revision

1

Dependencies

This extension is written against the SPIR-V Specification, Version 1.5 Revision 1.

This extension requires SPIR-V 1.4.

This extension requires SPV_KHR_ray_query or SPV_KHR_ray_tracing.

Overview

This extension adds new functionality to support the Vulkan VK_EXT_opacity_micromap extension in SPIR-V.

Extension Name

To use this extension within a SPIR-V module, the following OpExtension must be present in the module:

OpExtension "SPV_EXT_opacity_micromap"

Modifications to the SPIR-V Specification

(Modify sub-section 3.RF, Ray Flags, adding to the existing table)

3.RF, Ray Flags

Ray Flags Enabling Capabilities

1024

ForceOpacityMicromap2StateEXT
Force opacity micromaps intersected by this ray to be evaluated in the 2 state mode. See the Ray Opacity Micromap in the Vulkan API specification.

RayTracingOpacityMicromapEXT
(Modify Section 3.31, Capability, adding a row to the Capability table)
Capability Implicitly Declares

5381

RayTracingOpacityMicromapEXT
Uses the ForceOpacityMicromap2StateEXT enumerant.

Shader

Validation Rules

An OpExtension must be added to the SPIR-V for validation layers to check legal use of this extension:

OpExtension "SPV_EXT_opacity_micromap"

Issues

None yet.

Revision History

Rev Date Author Changes

1

2019-07-28

Eric Werness

Initial revision