VK_EXT_mesh_shader

Other Extension Metadata

Last Modified Date

2022-01-20

Interactions and External Dependencies

• This extension provides API support for GLSL_EXT_mesh_shader
• Interacts with Vulkan 1.1
• Interacts with VK_KHR_multiview
• Interacts with VK_KHR_fragment_shading_rate

Contributors

• Christoph Kubisch, NVIDIA
• Pat Brown, NVIDIA
• Jeff Bolz, NVIDIA
• Daniel Koch, NVIDIA
• Piers Daniell, NVIDIA
• Pierre Boudier, NVIDIA
• Patrick Mours, NVIDIA
• David Zhao Akeley, NVIDIA
• Kedarnath Thangudu, NVIDIA
• Timur Kristóf, Valve
• Hans-Kristian Arntzen, Valve
• Philip Rebohle, Valve
• Mike Blumenkrantz, Valve
• Slawomir Grajewski, Intel
• Michal Pietrasiuk, Intel
• Mariusz Merecki, Intel
• Tom Olson, ARM
• Jan-Harald Fredriksen, ARM
• Sandeep Kakarlapudi, ARM
• Ruihao Zhang, QUALCOMM
• Ricardo Garcia, Igalia, S.L.
• Tobias Hector, AMD
• Stu Smith, AMD

Description

This extension provides a new mechanism allowing applications to generate collections of geometric primitives via programmable mesh shading. It is an alternative to the existing programmable primitive shading pipeline, which relied on generating input primitives by a fixed function assembler as well as fixed function vertex fetch.

This extension also adds support for the following SPIR-V extension in Vulkan:

• SPV_EXT_mesh_shader

New Commands

• vkCmdDrawMeshTasksEXT
• vkCmdDrawMeshTasksIndirectEXT

If VK_KHR_draw_indirect_count or Vulkan Version 1.2 is supported:

• vkCmdDrawMeshTasksIndirectCountEXT

New Structures

• VkDrawMeshTasksIndirectCommandEXT
• Extending VkPhysicalDeviceFeatures2, VkDeviceCreateInfo:
  • VkPhysicalDeviceMeshShaderFeaturesEXT
• Extending VkPhysicalDeviceProperties2:
  • VkPhysicalDeviceMeshShaderPropertiesEXT

New Enum Constants

• VK_EXT_MESH_SHADER_EXTENSION_NAME
• VK_EXT_MESH_SHADER_SPEC_VERSION
• Extending VkPipelineStageFlagBits:
  • VK_PIPELINE_STAGE_MESH_SHADER_BIT_EXT
  • VK_PIPELINE_STAGE_TASK_SHADER_BIT_EXT
• Extending VkQueryPipelineStatisticFlagBits:
  • VK_QUERY_PIPELINE_STATISTIC_MESH_SHADER_INVOCATIONS_BIT_EXT
  • VK_QUERY_PIPELINE_STATISTIC_TASK_SHADER_INVOCATIONS_BIT_EXT
• Extending VkQueryType:
  • VK_QUERY_TYPE_MESH_PRIMITIVES_GENERATED_EXT
• Extending VkShaderStageFlagBits:
  • VK_SHADER_STAGE_MESH_BIT_EXT
  • VK_SHADER_STAGE_TASK_BIT_EXT
• Extending VkStructureType:
  • VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_MESH_SHADER_FEATURES_EXT
  • VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_MESH_SHADER_PROPERTIES_EXT

If VK_EXT_device_generated_commands is supported:

• Extending VkIndirectCommandsTokenTypeEXT:
  • VK_INDIRECT_COMMANDS_TOKEN_TYPE_DRAW_MESH_TASKS_COUNT_EXT
  • VK_INDIRECT_COMMANDS_TOKEN_TYPE_DRAW_MESH_TASKS_EXT

If VK_NV_device_generated_commands is supported:

• Extending VkIndirectCommandsTokenTypeNV:
  • VK_INDIRECT_COMMANDS_TOKEN_TYPE_DRAW_MESH_TASKS_NV

New or Modified Built-In Variables

• CullPrimitiveEXT
• PrimitivePointIndicesEXT
• PrimitiveLineIndicesEXT
• PrimitiveTriangleIndicesEXT
• (modified)Position
• (modified)PointSize
• (modified)ClipDistance
• (modified)CullDistance
• (modified)PrimitiveId
• (modified)Layer
• (modified)ViewportIndex
• (modified)NumWorkgroups
• (modified)WorkgroupSize
• (modified)WorkgroupId
• (modified)LocalInvocationId
• (modified)GlobalInvocationId
• (modified)LocalInvocationIndex
• (modified)NumSubgroups
• (modified)SubgroupId
• (modified)DrawIndex
• (modified)PrimitiveShadingRateKHR
• (modified)ViewIndex

New SPIR-V Capability

• MeshShadingEXT

Version History

• Revision 1, 2022-03-08 (Christoph Kubisch, Daniel Koch, Patrick Mours)
  • Initial revision