Safe Haskell	Safe-Inferred
Language	Haskell2010

Vulkan.Extensions.VK_KHR_device_group_creation

Description

Name

VK_KHR_device_group_creation - instance extension

VK_KHR_device_group_creation

Name String: VK_KHR_device_group_creation

Extension Type

Instance extension

Registered Extension Number

71

Revision

1

Extension and Version Dependencies

Requires support for Vulkan 1.0

Deprecation state

Promoted to Vulkan 1.1

Contact

Jeff Bolz @jeffbolznv%0A*Here describe the issue or question you have about the VK_KHR_device_group_creation extension*

Other Extension Metadata

Last Modified Date: 2016-10-19

IP Status

No known IP claims.

Interactions and External Dependencies

Promoted to Vulkan 1.1 Core

Contributors

Jeff Bolz, NVIDIA

Description

This extension provides instance-level commands to enumerate groups of physical devices, and to create a logical device from a subset of one of those groups. Such a logical device can then be used with new features in the VK_KHR_device_group extension.

Promotion to Vulkan 1.1

All functionality in this extension is included in core Vulkan 1.1, with the KHR suffix omitted. The original type, enum and command names are still available as aliases of the core functionality.

New Commands

enumeratePhysicalDeviceGroupsKHR

New Structures

PhysicalDeviceGroupPropertiesKHR

Extending DeviceCreateInfo:
- DeviceGroupDeviceCreateInfoKHR

New Enum Constants

KHR_DEVICE_GROUP_CREATION_EXTENSION_NAME

KHR_DEVICE_GROUP_CREATION_SPEC_VERSION
MAX_DEVICE_GROUP_SIZE_KHR
Extending MemoryHeapFlagBits:
- MEMORY_HEAP_MULTI_INSTANCE_BIT_KHR
Extending StructureType:
- STRUCTURE_TYPE_DEVICE_GROUP_DEVICE_CREATE_INFO_KHR
- STRUCTURE_TYPE_PHYSICAL_DEVICE_GROUP_PROPERTIES_KHR

Examples

    VkDeviceCreateInfo devCreateInfo = { VK_STRUCTURE_TYPE_DEVICE_CREATE_INFO };
    // (not shown) fill out devCreateInfo as usual.
    uint32_t deviceGroupCount = 0;
    VkPhysicalDeviceGroupPropertiesKHR *props = NULL;

    // Query the number of device groups
    vkEnumeratePhysicalDeviceGroupsKHR(g_vkInstance, &deviceGroupCount, NULL);

    // Allocate and initialize structures to query the device groups
    props = (VkPhysicalDeviceGroupPropertiesKHR *)malloc(deviceGroupCount*sizeof(VkPhysicalDeviceGroupPropertiesKHR));
    for (i = 0; i < deviceGroupCount; ++i) {
        props[i].sType = VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_GROUP_PROPERTIES_KHR;
        props[i].pNext = NULL;
    }
    vkEnumeratePhysicalDeviceGroupsKHR(g_vkInstance, &deviceGroupCount, props);

    // If the first device group has more than one physical device. create
    // a logical device using all of the physical devices.
    VkDeviceGroupDeviceCreateInfoKHR deviceGroupInfo = { VK_STRUCTURE_TYPE_DEVICE_GROUP_DEVICE_CREATE_INFO_KHR };
    if (props[0].physicalDeviceCount > 1) {
        deviceGroupInfo.physicalDeviceCount = props[0].physicalDeviceCount;
        deviceGroupInfo.pPhysicalDevices = props[0].physicalDevices;
        devCreateInfo.pNext = &deviceGroupInfo;
    }

    vkCreateDevice(props[0].physicalDevices[0], &devCreateInfo, NULL, &g_vkDevice);
    free(props);