VulkanHub
Function Prototype

vkUpdateDescriptorSetWithTemplate

Update the contents of a descriptor set object using an update template

Once a VkDescriptorUpdateTemplate has been created, descriptor sets can be updated by calling:

void vkUpdateDescriptorSetWithTemplateKHR(
    VkDevice device,
    VkDescriptorSet descriptorSet,
    VkDescriptorUpdateTemplate descriptorUpdateTemplate,
    const void* pData);

Valid Usage

VUID-vkUpdateDescriptorSetWithTemplate-pData-01685

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-vkUpdateDescriptorSetWithTemplate-descriptorSet-06995

Host access to descriptorSet must be externally synchronized unless explicitly denoted otherwise for specific flags

Valid Usage (Implicit)

VUID-vkUpdateDescriptorSetWithTemplate-device-parameter

device must be a valid VkDevice handle

VUID-vkUpdateDescriptorSetWithTemplate-descriptorSet-parameter

descriptorSet must be a valid VkDescriptorSet handle

VUID-vkUpdateDescriptorSetWithTemplate-descriptorUpdateTemplate-parameter

descriptorUpdateTemplate must be a valid VkDescriptorUpdateTemplate handle

VUID-vkUpdateDescriptorSetWithTemplate-descriptorSet-parent

descriptorSet must have been created, allocated, or retrieved from device

VUID-vkUpdateDescriptorSetWithTemplate-descriptorUpdateTemplate-parent

descriptorUpdateTemplate must have been created, allocated, or retrieved from device

API Example

struct AppBufferView {
    VkBufferView bufferView;
    uint32_t     applicationRelatedInformation;
};

struct AppDataStructure
{
    VkDescriptorImageInfo  imageInfo;          // a single image info
    VkDescriptorBufferInfo bufferInfoArray[3]; // 3 buffer infos in an array
    AppBufferView          bufferView[2];      // An application-defined structure containing a bufferView
    // ... 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         // stride not required if descriptorCount is 1
    },

    // binding to an array of buffer descriptors
    {
        .binding = 1,
        .dstArrayElement = 0,
        .descriptorCount = 3,
        .descriptorType = VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER,
        .offset = offsetof(AppDataStructure, bufferInfoArray),
        .stride = sizeof(VkDescriptorBufferInfo)    // descriptor buffer infos are compact
    },

    // binding to an array of buffer views
    {
        .binding = 2,
        .dstArrayElement = 0,
        .descriptorCount = 2,
        .descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_TEXEL_BUFFER,
        .offset = offsetof(AppDataStructure, bufferView) +
                  offsetof(AppBufferView, bufferView),
        .stride = sizeof(AppBufferView)             // bufferViews do not have to be compact
    },
};

// create a descriptor update template for descriptor set updates
const VkDescriptorUpdateTemplateCreateInfo createInfo =
{
    .sType = VK_STRUCTURE_TYPE_DESCRIPTOR_UPDATE_TEMPLATE_CREATE_INFO,
    .pNext = NULL,
    .flags = 0,
    .descriptorUpdateEntryCount = 3,
    .pDescriptorUpdateEntries = descriptorUpdateTemplateEntries,
    .templateType = VK_DESCRIPTOR_UPDATE_TEMPLATE_TYPE_DESCRIPTOR_SET,
    .descriptorSetLayout = myLayout,
    .pipelineBindPoint = 0,     // ignored by given templateType
    .pipelineLayout = 0,        // ignored by given templateType
    .set = 0,                   // ignored by given templateType
};

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

AppDataStructure appData;

// fill appData here or cache it in your engine
vkUpdateDescriptorSetWithTemplate(myDevice, myDescriptorSet, myDescriptorUpdateTemplate, &appData);