Name Strings

SPV_NV_sample_mask_override_coverage

Contact

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

Contributors

  • Kerch Holt, NVIDIA

  • Daniel Koch, NVIDIA

Status

Complete.

Version

Last Modified Date

2017-02-15

Revision

3

Dependencies

This extension is written against the SPIR-V Specification, Version 1.1 Revision 4.

This extension requires SPIR-V 1.0.

Overview

This extension provides a new builtin variable decoration to support the OpenGL GL_NV_sample_mask_override_coverage and Vulkan VK_NV_sample_mask_override_coverage extensions in SPIR-V.

The OverrideCoverageNV decoration corresponds to the override_coverage layout qualifier annotation.

Extension Name

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

OpExtension "SPV_NV_sample_mask_override_coverage"

New Capabilities

This extension introduces a new capability:

SampleMaskOverrideCoverageNV

that depends on the SampleRateShading capability.

New Decorations

Decorations added under the SampleMaskOverrideCoverageNV capability

OverrideCoverageNV

New Builtins

None.

New Instructions

None.

Token Number Assignments

OverrideCoverageNV

5248

SampleMaskOverrideCoverageNV

5249

Modifications to the SPIR-V Specification, Version 1.1

(Modify Section 3.20, Decoration, adding a row to the Decoration table)
Decoration Required Capability Extra Operands

5248

OverrideCoverageNV
Allows the fragment shader to control whether the SampleMask builtin output can enable samples that were not covered by the original primitive, or that failed the early depth/stencil tests.

SampleMaskOverrideCoverageNV

(Modify Section 3.31, Capability, adding a row to the Capability table)
Capability Depends On Enabled by Extension

5249

SampleMaskOverrideCoverageNV

SampleRateShading

SPV_NV_sample_mask_override_coverage

Validation Rules

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

OpExtension "SPV_NV_sample_mask_override_coverage"

Issues

None.

Revision History

Rev Date Author Changes

1

2016-05-25

Kerch Holt

Initial revision

2

2016-11-24

Daniel Koch

Add capability, assign tokens. Improve formatting.

3

2017-02-15

Daniel Koch

Mark complete, mention Vulkan extension