VkPhysicalDeviceMeshShaderPropertiesEXT

The VkPhysicalDeviceMeshShaderPropertiesEXT structure is defined as:

typedef struct VkPhysicalDeviceMeshShaderPropertiesEXT {
    VkStructureType sType;
    void* pNext;
    uint32_t maxTaskWorkGroupTotalCount;
    uint32_t maxTaskWorkGroupCount[3];
    uint32_t maxTaskWorkGroupInvocations;
    uint32_t maxTaskWorkGroupSize[3];
    uint32_t maxTaskPayloadSize;
    uint32_t maxTaskSharedMemorySize;
    uint32_t maxTaskPayloadAndSharedMemorySize;
    uint32_t maxMeshWorkGroupTotalCount;
    uint32_t maxMeshWorkGroupCount[3];
    uint32_t maxMeshWorkGroupInvocations;
    uint32_t maxMeshWorkGroupSize[3];
    uint32_t maxMeshSharedMemorySize;
    uint32_t maxMeshPayloadAndSharedMemorySize;
    uint32_t maxMeshOutputMemorySize;
    uint32_t maxMeshPayloadAndOutputMemorySize;
    uint32_t maxMeshOutputComponents;
    uint32_t maxMeshOutputVertices;
    uint32_t maxMeshOutputPrimitives;
    uint32_t maxMeshOutputLayers;
    uint32_t maxMeshMultiviewViewCount;
    uint32_t meshOutputPerVertexGranularity;
    uint32_t meshOutputPerPrimitiveGranularity;
    uint32_t maxPreferredTaskWorkGroupInvocations;
    uint32_t maxPreferredMeshWorkGroupInvocations;
    VkBool32 prefersLocalInvocationVertexOutput;
    VkBool32 prefersLocalInvocationPrimitiveOutput;
    VkBool32 prefersCompactVertexOutput;
    VkBool32 prefersCompactPrimitiveOutput;
} VkPhysicalDeviceMeshShaderPropertiesEXT;

The members of the VkPhysicalDeviceMeshShaderPropertiesEXT structure describe the following implementation-dependent limits:

• sType is a VkStructureType value identifying this structure.
• pNext is NULL or a pointer to a structure extending this structure.
• maxTaskWorkGroupTotalCount is the maximum number of total local workgroups that can be launched by a single mesh tasks drawing command. See Programmable Mesh Shading.
• maxTaskWorkGroupCount[3] is the maximum number of local workgroups that can be launched by a single mesh tasks drawing command. These three values represent the maximum number of local workgroups for the X, Y, and Z dimensions, respectively. The workgroup count parameters to the drawing commands must be less than or equal to the corresponding limit. The product of these dimensions must be less than or equal to maxTaskWorkGroupTotalCount.
• maxTaskWorkGroupInvocations is the maximum total number of task shader invocations in a single local workgroup. The product of the X, Y, and Z sizes, as specified by the LocalSize or LocalSizeId execution mode in shader modules or by the object decorated by the WorkgroupSize decoration, must be less than or equal to this limit.
• maxTaskWorkGroupSize[3] is the maximum size of a local task workgroup, per dimension. These three values represent the maximum local workgroup size in the X, Y, and Z dimensions, respectively. The x, y, and z sizes, as specified by the LocalSize or LocalSizeId execution mode or by the object decorated by the WorkgroupSize decoration in shader modules, must be less than or equal to the corresponding limit.
• maxTaskPayloadSize is the maximum total storage size, in bytes, available for variables declared with the TaskPayloadWorkgroupEXT storage class in shader modules in the task shader stage.
• maxTaskSharedMemorySize is the maximum total storage size, in bytes, available for variables declared with the Workgroup storage class in shader modules in the task shader stage.
• maxTaskPayloadAndSharedMemorySize is the maximum total storage size, in bytes, available for variables that are declared with the TaskPayloadWorkgroupEXT or Workgroup storage class, in shader modules in the task shader stage.
• maxMeshWorkGroupTotalCount is the maximum number of local output tasks a single task shader workgroup can emit.
• maxMeshWorkGroupCount[3] is the maximum number of local output tasks a single task shader workgroup can emit, per dimension. These three values represent the maximum number of local output tasks for the X, Y, and Z dimensions, respectively. The workgroup count parameters to the OpEmitMeshTasksEXT must be less than or equal to the corresponding limit. The product of these dimensions must be less than or equal to maxMeshWorkGroupTotalCount.
• maxMeshWorkGroupInvocations is the maximum total number of mesh shader invocations in a single local workgroup. The product of the X, Y, and Z sizes, as specified by the LocalSize or LocalSizeId execution mode in shader modules or by the object decorated by the WorkgroupSize decoration, must be less than or equal to this limit.
• maxMeshWorkGroupSize[3] is the maximum size of a local mesh workgroup, per dimension. These three values represent the maximum local workgroup size in the X, Y, and Z dimensions, respectively. The x, y, and z sizes, as specified by the LocalSize or LocalSizeId execution mode or by the object decorated by the WorkgroupSize decoration in shader modules, must be less than or equal to the corresponding limit.
• maxMeshSharedMemorySize is the maximum total storage size, in bytes, available for variables declared with the Workgroup storage class in shader modules in the mesh shader stage.
• maxMeshPayloadAndSharedMemorySize is the maximum total storage size, in bytes, available for variables that are declared with the TaskPayloadWorkgroupEXT or Workgroup storage class in shader modules in the mesh shader stage.
• maxMeshOutputMemorySize is the maximum total storage size, in bytes, available for output variables in shader modules in the mesh shader stage, according to the formula in Mesh Shader Output.
• maxMeshPayloadAndOutputMemorySize is the maximum total storage size, in bytes, available for variables that are declared with the TaskPayloadWorkgroupEXT storage class, or output variables in shader modules in the mesh shader stage, according to the formula in Mesh Shader Output.
• maxMeshOutputComponents is the maximum number of components of output variables which can be output from the mesh shader stage.
• maxMeshOutputVertices is the maximum number of vertices which can be emitted by a single mesh shader workgroup.
• maxMeshOutputPrimitives is the maximum number of primitives which can be emitted by a single mesh shader workgroup.
• maxMeshOutputLayers is one greater than the maximum layer index that can be output from the mesh shader stage.
• maxMeshMultiviewViewCount is one greater than the maximum view index that can be used by any mesh shader.
• meshOutputPerVertexGranularity is the granularity of vertex allocation. The number of output vertices allocated for the mesh shader stage is padded to a multiple of this number. The value can be used to calculate the required storage size for output variables in shader modules in the mesh shader stage, which must be less than or equal to maxMeshOutputMemorySize.
• meshOutputPerPrimitiveGranularity is the granularity of primitive allocation. The number of output primitives allocated for the mesh shader stage is padded to a multiple of this number. The value can be used to calculate the required storage size for output variables in shader modules in the mesh shader stage, which must be less than or equal to maxMeshOutputMemorySize.
• maxPreferredTaskWorkGroupInvocations is the maximum number of task shader invocations in a single workgroup that is preferred by the implementation for optimal performance. The value is guaranteed to be a multiple of a supported subgroup size for the task shader stage.
• maxPreferredMeshWorkGroupInvocations is the maximum number of mesh shader invocations in a single workgroup that is preferred by the implementation for optimal performance. The value is guaranteed to be a multiple of a supported subgroup size for the mesh shader stage.
• prefersLocalInvocationVertexOutput specifies whether writes to the vertex output array in a mesh shader yield best performance when the array index matches LocalInvocationIndex.
• prefersLocalInvocationPrimitiveOutput specifies whether writes to the primitive output array in a mesh shader yield best performance when the array index matches LocalInvocationIndex.
• prefersCompactVertexOutput specifies whether output vertices should be compacted after custom culling in the mesh shader for best performance, otherwise keeping the vertices at their original location may be better.
• prefersCompactPrimitiveOutput specifies whether output primitives should be compacted after custom culling in the mesh shader for best performance, otherwise the use of CullPrimitiveEXT may be better.

If the VkPhysicalDeviceMeshShaderPropertiesEXT structure is included in the pNext chain of VkPhysicalDeviceProperties2, it is filled with the implementation-dependent limits.