Struct ccthw_ash_instance::QueueFamilyInfo

pub struct QueueFamilyInfo { /* private fields */ }

The logical device constructor uses an array of these structs to build the Vulkan DeviceQueueCreateInfo structs.

It’s convenient to use this wrapper instead of the raw DeviceQueueCreateInfo structs because the raw structs include a pointer to an array of priorities. It can be unwieldy to handle the raw pointer without introducing memory safety problems, so this struct owns a vector of priority values.

Examples

use ccthw_ash_instance::QueueFamilyInfo;

let mut queue_family_info = QueueFamilyInfo::new(2);
queue_family_info.add_queue_priority(1.0);

// NOTE - create_info is only valid while QueueFamilyInfo exists and no
//        additional calls to add_queue_priority are made.
let create_info = unsafe { queue_family_info.as_queue_create_info() };
println!("{:#?}", create_info);

Implementations

impl QueueFamilyInfo

pub fn new(queue_family_index: u32) -> Self

Create a new instance with no queue priorities.

Params

• queue_family_index - index for the underlying queue family. This comes from enumerating the physical devices queue family properties.

pub fn add_queue_priority(&mut self, priority: f32)

Add a queue with the given priority.

Params

• priority - should be between 0.0 and 1.0. Implementations are allowed to give more resources to higher-priority queues, but it isn’t required. If you don’t have a good reason to do otherwise, 1.0 is a reasonable choice.

pub unsafe fn as_queue_create_info(&self) -> DeviceQueueCreateInfo

Get a DeviceQueueCreateInfo struct based on the number of queue priorities specified for this queue family.

Safety

Unsafe because the device queue create info struct contains a pointer to the queue_priorities vector. This means that if any queue priorities are added AFTER calling this function, then using the struct will cause undefined behavior.

Trait Implementations

impl Clone for QueueFamilyInfo

fn clone(&self) -> QueueFamilyInfo

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for QueueFamilyInfo

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.