public Class KHRDescriptorUpdateTemplate

Extends VkDebugReportObjectTypeEXT.

Extends VkDescriptorUpdateTemplateType.

Extends VkDescriptorUpdateTemplateType.

The extension name.

The extension specification version.

Extends VkObjectType.

Extends VkStructureType.

Unsafe version of: CreateDescriptorUpdateTemplateKHR

Unsafe version of: DestroyDescriptorUpdateTemplateKHR

Pushes descriptor updates into a command buffer using a descriptor update template.

C Specification

It is also possible to use a descriptor update template to specify the push descriptors to update. To do so, call:

void vkCmdPushDescriptorSetWithTemplateKHR(
    VkCommandBuffer                             commandBuffer,
    VkDescriptorUpdateTemplate                  descriptorUpdateTemplate,
    VkPipelineLayout                            layout,
    uint32_t                                    set,
    const void*                                 pData);

Valid Usage

• The pipelineBindPoint specified during the creation of the descriptor update template must be supported by the commandBuffer’s parent VkCommandPool’s queue family
• pData must be a valid pointer to a memory containing one or more valid instances of VkDescriptorImageInfo, VkDescriptorBufferInfo, or VkBufferView in a layout defined by descriptorUpdateTemplate when it was created with CreateDescriptorUpdateTemplate
• layout must be compatible with the layout used to create descriptorUpdateTemplate
• descriptorUpdateTemplate must have been created with a templateType of DESCRIPTOR_UPDATE_TEMPLATE_TYPE_PUSH_DESCRIPTORS_KHR
• set must be the same value used to create descriptorUpdateTemplate
• set must be less than VkPipelineLayoutCreateInfo::setLayoutCount provided when layout was created
• set must be the unique set number in the pipeline layout that uses a descriptor set layout that was created with DESCRIPTOR_SET_LAYOUT_CREATE_PUSH_DESCRIPTOR_BIT_KHR

Valid Usage (Implicit)

• commandBuffer must be a valid VkCommandBuffer handle
• descriptorUpdateTemplate must be a valid VkDescriptorUpdateTemplate handle
• layout must be a valid VkPipelineLayout handle
• commandBuffer must be in the recording state
• The VkCommandPool that commandBuffer was allocated from must support graphics, or compute operations
• This command must only be called outside of a video coding scope
• Each of commandBuffer, descriptorUpdateTemplate, and layout must have been created, allocated, or retrieved from the same VkDevice

Host Synchronization

• Host access to commandBuffer must be externally synchronized
• Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties

struct AppDataStructure
{
    VkDescriptorImageInfo  imageInfo;          // a single image info
    // ... some more application related data
};

const VkDescriptorUpdateTemplateEntry descriptorUpdateTemplateEntries[] =
{
    // binding to a single image descriptor
    {
        .binding = 0,
        .dstArrayElement = 0,
        .descriptorCount = 1,
        .descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER,
        .offset = offsetof(AppDataStructure, imageInfo),
        .stride = 0     // not required if descriptorCount is 1
    }
};

// create a descriptor update template for push descriptor set updates
const VkDescriptorUpdateTemplateCreateInfo createInfo =
{
    .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_UPDATE_TEMPLATE_CREATE_INFO,
    .pNext = NULL,
    .flags = 0,
    .descriptorUpdateEntryCount = 1,
    .pDescriptorUpdateEntries = descriptorUpdateTemplateEntries,
    .templateType = VK_DESCRIPTOR_UPDATE_TEMPLATE_TYPE_PUSH_DESCRIPTORS_KHR,
    .descriptorSetLayout = 0,   // ignored by given templateType
    .pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS,
    .pipelineLayout = myPipelineLayout,
    .set = 0,
};

VkDescriptorUpdateTemplate myDescriptorUpdateTemplate;
myResult = vkCreateDescriptorUpdateTemplate(
    myDevice,
    &createInfo,
    NULL,
    &myDescriptorUpdateTemplate);

AppDataStructure appData;
// fill appData here or cache it in your engine
vkCmdPushDescriptorSetWithTemplateKHR(myCmdBuffer, myDescriptorUpdateTemplate, myPipelineLayout, 0,&appData);

Parameters

commandBuffer:VkCommandBuffer

the command buffer that the descriptors will be recorded in.

descriptorUpdateTemplate:long

a descriptor update template defining how to interpret the descriptor information in pData.

layout:long

a VkPipelineLayout object used to program the bindings. It must be compatible with the layout used to create the descriptorUpdateTemplate handle.

set:int

the set number of the descriptor set in the pipeline layout that will be updated. This must be the same number used to create the descriptorUpdateTemplate handle.

pData:long

a pointer to memory containing descriptors for the templated update.

See CreateDescriptorUpdateTemplate.

Parameters

device:VkDevice

the logical device that creates the descriptor update template.

pCreateInfo:VkDescriptorUpdateTemplateCreateInfo

a pointer to a VkDescriptorUpdateTemplateCreateInfo structure specifying the set of descriptors to update with a single call to CmdPushDescriptorSetWithTemplateKHR or UpdateDescriptorSetWithTemplate.

pAllocator:VkAllocationCallbacks

controls host memory allocation as described in the Memory Allocation chapter.

pDescriptorUpdateTemplate:LongBuffer

a pointer to a VkDescriptorUpdateTemplate handle in which the resulting descriptor update template object is returned.

Annotations

@NativeType:VkResult

Array version of: CreateDescriptorUpdateTemplateKHR

Annotations

@NativeType:VkResult

See DestroyDescriptorUpdateTemplate.

Parameters

device:VkDevice

the logical device that has been used to create the descriptor update template

descriptorUpdateTemplate:long

the descriptor update template to destroy.

pAllocator:VkAllocationCallbacks

controls host memory allocation as described in the Memory Allocation chapter.

See UpdateDescriptorSetWithTemplate.

Parameters

device:VkDevice

the logical device that updates the descriptor set.

descriptorSet:long

the descriptor set to update

descriptorUpdateTemplate:long

a VkDescriptorUpdateTemplate object specifying the update mapping between pData and the descriptor set to update.

pData:long

a pointer to memory containing one or more VkDescriptorImageInfo, VkDescriptorBufferInfo, or VkBufferView structures or VkAccelerationStructureKHR or VkAccelerationStructureNV handles used to write the descriptors.