VkDescriptorSetVariableDescriptorCountAllocateInfo(3)

# VkDescriptorSetVariableDescriptorCountAllocateInfo(3) Manual Page

## Name

VkDescriptorSetVariableDescriptorCountAllocateInfo - Structure specifying additional allocation parameters for descriptor sets

## C Specification

If the `pNext` chain of a VkDescriptorSetAllocateInfo structure includes a `VkDescriptorSetVariableDescriptorCountAllocateInfo` structure, then that structure includes an array of descriptor counts for variable-sized descriptor bindings, one for each descriptor set being allocated.

The `VkDescriptorSetVariableDescriptorCountAllocateInfo` structure is defined as:

    // Provided by VK_VERSION_1_2
    typedef struct VkDescriptorSetVariableDescriptorCountAllocateInfo {
        VkStructureType    sType;
        const void*        pNext;
        uint32_t           descriptorSetCount;
        const uint32_t*    pDescriptorCounts;
    } VkDescriptorSetVariableDescriptorCountAllocateInfo;

    // Provided by VK_EXT_descriptor_indexing
    // Equivalent to VkDescriptorSetVariableDescriptorCountAllocateInfo
    typedef VkDescriptorSetVariableDescriptorCountAllocateInfo VkDescriptorSetVariableDescriptorCountAllocateInfoEXT;

## Members

- `sType` is a VkStructureType value identifying this structure.

- `pNext` is `NULL` or a pointer to a structure extending this structure.

- `descriptorSetCount` is zero or the number of elements in `pDescriptorCounts`.

- `pDescriptorCounts` is a pointer to an array of descriptor counts, with each member specifying the number of descriptors in a variable-sized descriptor binding in the corresponding descriptor set being allocated.

## Description

If `descriptorSetCount` is zero or this structure is not included in the `pNext` chain, then the variable lengths are considered to be zero. Otherwise, `pDescriptorCounts`[i] is the number of descriptors in the variable-sized descriptor binding in the corresponding descriptor set layout. If the variable-sized descriptor binding in the corresponding descriptor set layout has a descriptor type of VK_DESCRIPTOR_TYPE_INLINE_UNIFORM_BLOCK then `pDescriptorCounts`[i] specifies the binding’s capacity in bytes. If VkDescriptorSetAllocateInfo::`pSetLayouts`[i] does not include a variable-sized descriptor binding, then `pDescriptorCounts`[i] is ignored.

Valid Usage

- VUID-VkDescriptorSetVariableDescriptorCountAllocateInfo-descriptorSetCount-03045
  If `descriptorSetCount` is not zero, `descriptorSetCount` must equal VkDescriptorSetAllocateInfo::`descriptorSetCount`

Valid Usage (Implicit)

- VUID-VkDescriptorSetVariableDescriptorCountAllocateInfo-sType-sType
  `sType` must be VK_STRUCTURE_TYPE_DESCRIPTOR_SET_VARIABLE_DESCRIPTOR_COUNT_ALLOCATE_INFO

- VUID-VkDescriptorSetVariableDescriptorCountAllocateInfo-pDescriptorCounts-parameter
  If `descriptorSetCount` is not `0`, `pDescriptorCounts` must be a valid pointer to an array of `descriptorSetCount` `uint32_t` values

Structure Chaining

Extends the structure

  - VkDescriptorSetAllocateInfo

## See Also

VK_EXT_descriptor_indexing, VK_VERSION_1_2, VkStructureType

## Document Notes

For more information, see the Vulkan Specification.

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.

## Copyright

Copyright 2014-2026 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0