VK_NV_compute_shader_derivatives
Other Extension Metadata
Last Modified Date
2018-07-19
IP Status
No known IP claims.
Interactions and External Dependencies
- This extension provides API support for
GL_NV_compute_shader_derivatives
Contributors
- Pat Brown, NVIDIA
Description
This extension adds Vulkan support for the
SPV_NV_compute_shader_derivatives
SPIR-V extension.
The SPIR-V extension provides two new execution modes, both of which allow
compute shaders to use built-ins that evaluate compute derivatives
explicitly or implicitly.
Derivatives will be computed via differencing over a 2x2 group of shader
invocations.
The DerivativeGroupQuadsNV
execution mode assembles shader invocations
into 2x2 groups, where each group has x and y coordinates of the local
invocation ID of the form (2m+{0,1}, 2n+{0,1}).
The DerivativeGroupLinearNV
execution mode assembles shader invocations
into 2x2 groups, where each group has local invocation index values of the
form 4m+{0,1,2,3}.
New Structures
- Extending VkPhysicalDeviceFeatures2, VkDeviceCreateInfo:
New Enum Constants
VK_NV_COMPUTE_SHADER_DERIVATIVES_EXTENSION_NAME
VK_NV_COMPUTE_SHADER_DERIVATIVES_SPEC_VERSION
- Extending VkStructureType:
VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_COMPUTE_SHADER_DERIVATIVES_FEATURES_NV
New SPIR-V Capability
Issues
(1) Should we specify that the groups of four shader invocations used for
derivatives in a compute shader are the same groups of four invocations that
form a quad
in shader subgroups?
RESOLVED: Yes.
Examples
None.
Version History
- Revision 1, 2018-07-19 (Pat Brown)
- Initial draft