## C Specification

The VkPhysicalDeviceSubgroupSizeControlFeatures structure is defined as:

// Provided by VK_VERSION_1_3
typedef struct VkPhysicalDeviceSubgroupSizeControlFeatures {
VkStructureType    sType;
void*              pNext;
VkBool32           subgroupSizeControl;
VkBool32           computeFullSubgroups;
} VkPhysicalDeviceSubgroupSizeControlFeatures;

or the equivalent

// Provided by VK_EXT_subgroup_size_control
typedef VkPhysicalDeviceSubgroupSizeControlFeatures VkPhysicalDeviceSubgroupSizeControlFeaturesEXT;

## Members

This structure describes the following features:

## Description

• sType is the type of this structure.

• pNext is NULL or a pointer to a structure extending this structure.

• subgroupSizeControl indicates whether the implementation supports controlling shader subgroup sizes via the VK_PIPELINE_SHADER_STAGE_CREATE_ALLOW_VARYING_SUBGROUP_SIZE_BIT flag and the VkPipelineShaderStageRequiredSubgroupSizeCreateInfo structure.

• computeFullSubgroups indicates whether the implementation supports requiring full subgroups in compute , mesh, or task shaders via the VK_PIPELINE_SHADER_STAGE_CREATE_REQUIRE_FULL_SUBGROUPS_BIT flag.

If the VkPhysicalDeviceSubgroupSizeControlFeatures structure is included in the pNext chain of the VkPhysicalDeviceFeatures2 structure passed to vkGetPhysicalDeviceFeatures2, it is filled in to indicate whether each corresponding feature is supported. VkPhysicalDeviceSubgroupSizeControlFeatures can also be used in the pNext chain of VkDeviceCreateInfo to selectively enable these features.

 Note The VkPhysicalDeviceSubgroupSizeControlFeaturesEXT structure was added in version 2 of the VK_EXT_subgroup_size_control extension. Version 1 implementations of this extension will not fill out the features structure but applications may assume that both subgroupSizeControl and computeFullSubgroups are supported if the extension is supported. (See also the Feature Requirements section.) Applications are advised to add a VkPhysicalDeviceSubgroupSizeControlFeaturesEXT structure to the pNext chain of VkDeviceCreateInfo to enable the features regardless of the version of the extension supported by the implementation. If the implementation only supports version 1, it will safely ignore the VkPhysicalDeviceSubgroupSizeControlFeaturesEXT structure. Vulkan 1.3 implementations always support the features structure.
Valid Usage (Implicit)
• VUID-VkPhysicalDeviceSubgroupSizeControlFeatures-sType-sType
sType must be VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_SUBGROUP_SIZE_CONTROL_FEATURES