C Specification

The VkDescriptorSetAndBindingMappingEXT structure is defined as:

// Provided by VK_EXT_descriptor_heap
typedef struct VkDescriptorSetAndBindingMappingEXT {
    VkStructureType                     sType;
    const void*                         pNext;
    uint32_t                            descriptorSet;
    uint32_t                            firstBinding;
    uint32_t                            bindingCount;
    VkSpirvResourceTypeFlagsEXT         resourceMask;
    VkDescriptorMappingSourceEXT        source;
    VkDescriptorMappingSourceDataEXT    sourceData;
} VkDescriptorSetAndBindingMappingEXT;

Members

  • sType is a VkStructureType value identifying this structure.

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

  • descriptorSet is the value of DescriptorSet for resources that this mapping affects.

  • firstBinding is the first value of Binding of resources that this mapping affects.

  • bindingCount is the number of consecutive Binding values of resources that this mapping affects.

  • resourceMask is a mask of VkSpirvResourceTypeFlagBitsEXT values indicating which resource types are specified by this mapping.

  • source is a VkDescriptorMappingSourceEXT value specifying the method of mapping specified for the affected resources.

  • sourceData is a VkDescriptorMappingSourceDataEXT that provides the details of how each mapping is specified according to source.

Description

Resources specified in a shader with a DescriptorSet decoration set to descriptorSet, a Binding decoration greater than or equal to firstBinding and less than the sum of firstBinding and bindingCount, and a resource type matching one of the bits in resourceMask will be mapped according to source and sourceData.

Note

Applications are free to overspecify bindings that are not present; allowing reuse of the same mapping structures with multiple shaders, even when those shaders only partially reuse those mappings. This includes things like setting binding counts higher than the number used in the shader, specifying bindings that are not present in the shader, and setting resourceMask to all possible resources that may be encountered.

If source selects an element of sourceData defined by a structure, the description of that structure defines how resources are mapped. Source mappings using a single base type are defined here.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_HEAP_WITH_CONSTANT_OFFSET_EXT, the resource will be backed by heap data as specified by constantOffset.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_HEAP_WITH_PUSH_INDEX_EXT, the resource will be backed by heap data as specified by pushIndex.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_HEAP_WITH_INDIRECT_INDEX_EXT, the resource will be backed by heap data as specified by indirectIndex.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_HEAP_WITH_INDIRECT_INDEX_ARRAY_EXT, the resource will be backed by heap data as specified by indirectIndexArray.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_RESOURCE_HEAP_DATA_EXT, the resource will be backed by heap data as specified by heapData.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_PUSH_DATA_EXT, the resource will be backed by push data at a range from pushDataOffset to the size of the resource, allowing a uniform buffer to be backed by push data access push data. Accessing data in the uniform buffer at an offset of shaderOffset in the shader will access push data at an offset equal to

offset = shaderOffset + pushDataOffset.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_PUSH_ADDRESS_EXT, the resource will be backed by data pointed to by a device address in push data at an offset of pushAddressOffset. Accessing data via the mapped resource in the shader will access data backing the address specified in push data:

address = ((VkDeviceAddress*)pPushData)[pushAddressOffset/8]

where pPushData is the total set of push data specified by vkCmdPushDataEXT. If the shader resource is an acceleration structure, the address must be a valid acceleration structure address.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_INDIRECT_ADDRESS_EXT, the resource will be backed by heap data as specified by indirectAddress.

Note

Accesses to resources using mappings to anything that is not a descriptor in a heap are not subject to robustness guarantees; resources for such mappings must not be accessed out of bounds.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_HEAP_WITH_SHADER_RECORD_INDEX_EXT, the resource will be backed by heap data as specified by shaderRecordIndex.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_SHADER_RECORD_DATA_EXT, the resource will be backed by shader record data at a range from shaderRecordDataOffset to the size of the resource, allowing a uniform buffer to be used as a way to access shader record data. Accessing data in the uniform buffer at an offset shaderOffset in the shader will access shader record data at an offset equal to

offset = shaderOffset + shaderRecordDataOffset.

If source is VK_DESCRIPTOR_MAPPING_SOURCE_SHADER_RECORD_ADDRESS_EXT, the resource will be backed by data pointed to by a device address in the shader record at shaderRecordAddressOffset. Accessing data via the mapped resource in the shader will access data backing the address specified in shader record data:

address = ((VkDeviceAddress*)pShaderRecordData)[shaderRecordAddressOffset/8]

where pShaderRecord is the memory associated with a given shader as its shader record. If the shader resource is an acceleration structure, the address must be a valid acceleration structure address.

Note

Accesses to resources using VK_DESCRIPTOR_MAPPING_SOURCE_SHADER_RECORD_ADDRESS_EXT mappings are not subject to robustness guarantees; data must not be accessed outside of the allocated memory range.

Mappings must be declared for all variables with a DescriptorSet and Binding in the shader resource interface.

Valid Usage
Valid Usage (Implicit)

See Also

VK_EXT_descriptor_heap, VkDescriptorMappingSourceDataEXT, VkDescriptorMappingSourceEXT, VkShaderDescriptorSetAndBindingMappingInfoEXT, VkSpirvResourceTypeFlagsEXT, 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