C Specification

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

// Provided by VK_VERSION_1_1 with VK_KHR_push_descriptor, VK_KHR_descriptor_update_template with VK_KHR_push_descriptor
void vkCmdPushDescriptorSetWithTemplateKHR(
    VkCommandBuffer                             commandBuffer,
    VkDescriptorUpdateTemplate                  descriptorUpdateTemplate,
    VkPipelineLayout                            layout,
    uint32_t                                    set,
    const void*                                 pData);

Parameters

  • commandBuffer is the command buffer that the descriptors will be recorded in.

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

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

  • set is 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 is a pointer to memory containing descriptors for the templated update.

Description

Valid Usage

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-commandBuffer-00366
    The pipelineBindPoint specified during the creation of the descriptor update template must be supported by the commandBuffer’s parent VkCommandPool’s queue family

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-pData-01686
    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 vkCreateDescriptorUpdateTemplate

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-layout-07993
    layout must be compatible with the layout used to create descriptorUpdateTemplate

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-descriptorUpdateTemplate-07994
    descriptorUpdateTemplate must have been created with a templateType of VK_DESCRIPTOR_UPDATE_TEMPLATE_TYPE_PUSH_DESCRIPTORS_KHR

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-set-07995
    set must be the same value used to create descriptorUpdateTemplate

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-set-07304
    set must be less than VkPipelineLayoutCreateInfo::setLayoutCount provided when layout was created

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-set-07305
    set must be the unique set number in the pipeline layout that uses a descriptor set layout that was created with VK_DESCRIPTOR_SET_LAYOUT_CREATE_PUSH_DESCRIPTOR_BIT_KHR

Valid Usage (Implicit)

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-commandBuffer-parameter
    commandBuffer must be a valid VkCommandBuffer handle

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-descriptorUpdateTemplate-parameter
    descriptorUpdateTemplate must be a valid VkDescriptorUpdateTemplate handle

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-layout-parameter
    layout must be a valid VkPipelineLayout handle

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-commandBuffer-recording
    commandBuffer must be in the recording state

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-commandBuffer-cmdpool
    The VkCommandPool that commandBuffer was allocated from must support graphics, or compute operations

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-videocoding
    This command must only be called outside of a video coding scope

  • VUID-vkCmdPushDescriptorSetWithTemplateKHR-commonparent
    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
Command Buffer Levels Render Pass Scope Video Coding Scope Supported Queue Types Command Type

Primary
Secondary

Both

Outside

Graphics
Compute

State
API example
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);

See Also

VK_KHR_descriptor_update_template, VK_KHR_push_descriptor, VK_VERSION_1_1, VkCommandBuffer, VkDescriptorUpdateTemplate, VkPipelineLayout

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 2014-2024 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0