C Specification
Once a VkDescriptorUpdateTemplate
has been created, descriptor sets
can be updated by calling:
// Provided by VK_VERSION_1_1
void vkUpdateDescriptorSetWithTemplate(
VkDevice device,
VkDescriptorSet descriptorSet,
VkDescriptorUpdateTemplate descriptorUpdateTemplate,
const void* pData);
or the equivalent command
// Provided by VK_KHR_descriptor_update_template
void vkUpdateDescriptorSetWithTemplateKHR(
VkDevice device,
VkDescriptorSet descriptorSet,
VkDescriptorUpdateTemplate descriptorUpdateTemplate,
const void* pData);
Parameters
-
device
is the logical device that updates the descriptor set. -
descriptorSet
is the descriptor set to update -
descriptorUpdateTemplate
is a VkDescriptorUpdateTemplate object specifying the update mapping betweenpData
and the descriptor set to update. -
pData
is a pointer to memory containing one or more VkDescriptorImageInfo, VkDescriptorBufferInfo, or VkBufferView structures or VkAccelerationStructureKHR or VkAccelerationStructureNV handles used to write the descriptors.
Description
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
{
0, // binding
0, // dstArrayElement
1, // descriptorCount
VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, // descriptorType
offsetof(AppDataStructure, imageInfo), // offset
0 // stride is not required if descriptorCount is 1
},
// binding to an array of buffer descriptors
{
1, // binding
0, // dstArrayElement
3, // descriptorCount
VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER, // descriptorType
offsetof(AppDataStructure, bufferInfoArray), // offset
sizeof(VkDescriptorBufferInfo) // stride, descriptor buffer infos are compact
},
// binding to an array of buffer views
{
2, // binding
0, // dstArrayElement
2, // descriptorCount
VK_DESCRIPTOR_TYPE_STORAGE_TEXEL_BUFFER, // descriptorType
offsetof(AppDataStructure, bufferView) +
offsetof(AppBufferView, bufferView), // offset
sizeof(AppBufferView) // stride, bufferViews do not have to be compact
},
};
// create a descriptor update template for descriptor set updates
const VkDescriptorUpdateTemplateCreateInfo createInfo =
{
VK_STRUCTURE_TYPE_DESCRIPTOR_UPDATE_TEMPLATE_CREATE_INFO, // sType
NULL, // pNext
0, // flags
3, // descriptorUpdateEntryCount
descriptorUpdateTemplateEntries, // pDescriptorUpdateEntries
VK_DESCRIPTOR_UPDATE_TEMPLATE_TYPE_DESCRIPTOR_SET, // templateType
myLayout, // descriptorSetLayout
0, // pipelineBindPoint, ignored by given templateType
0, // pipelineLayout, ignored by given templateType
0, // set, 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);
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.