Struct ARFaceTrackingConfiguration 

pub struct ARFaceTrackingConfiguration { /* private fields */ }

Available on crate features ARConfiguration and objc2 only.

A configuration for running face tracking.

Face tracking uses the front facing camera to track the face in 3D providing details on the topology and expression of the face. A detected face will be added to the session as an ARFaceAnchor object which contains information about head pose, mesh, eye pose, and blend shape coefficients. If light estimation is enabled the detected face will be treated as a light probe and used to estimate the direction of incoming light.

See also Apple’s documentation

Implementations

impl ARFaceTrackingConfiguration

pub unsafe fn supportedNumberOfTrackedFaces() -> NSInteger

Maximum number of faces which can be tracked simultaneously.

pub unsafe fn maximumNumberOfTrackedFaces(&self) -> NSInteger

Maximum number of faces to track simultaneously.

Setting the maximum number of tracked faces will limit the number of faces that can be tracked in a given frame. If more than the maximum is visible, only the faces already being tracked will continue to track until tracking is lost or another face is removed. Default value is one.

pub unsafe fn setMaximumNumberOfTrackedFaces( &self, maximum_number_of_tracked_faces: NSInteger, )

Setter for maximumNumberOfTrackedFaces.

pub unsafe fn supportsWorldTracking() -> bool

Indicates whether world tracking can be enabled on this device.

pub unsafe fn isWorldTrackingEnabled(&self) -> bool

Enable or disable World Tracking. Disabled by default.

When enabled, ARSession uses the back facing camera to track the device’s orientation and position in the world. The camera transform and the ARFaceAnchor transform will be in the world coordinate space.

pub unsafe fn setWorldTrackingEnabled(&self, world_tracking_enabled: bool)

Setter for isWorldTrackingEnabled.

pub unsafe fn init(this: Allocated<Self>) -> Retained<Self>

pub unsafe fn new() -> Retained<Self>

Methods from Deref<Target = ARConfiguration>

pub unsafe fn videoFormat(&self) -> Retained<ARVideoFormat>

Available on crate feature ARVideoFormat only.

Video format of the session output.

pub unsafe fn setVideoFormat(&self, video_format: &ARVideoFormat)

Available on crate feature ARVideoFormat only.

Setter for videoFormat.

pub unsafe fn worldAlignment(&self) -> ARWorldAlignment

Determines how the coordinate system should be aligned with the world.

The default is ARWorldAlignmentGravity.

pub unsafe fn setWorldAlignment(&self, world_alignment: ARWorldAlignment)

Setter for worldAlignment.

pub unsafe fn isLightEstimationEnabled(&self) -> bool

Enable or disable light estimation.

Enabled by default.

pub unsafe fn setLightEstimationEnabled(&self, light_estimation_enabled: bool)

Setter for isLightEstimationEnabled.

pub unsafe fn providesAudioData(&self) -> bool

Determines whether to capture and provide audio data.

Disabled by default.

pub unsafe fn setProvidesAudioData(&self, provides_audio_data: bool)

Setter for providesAudioData.

pub unsafe fn frameSemantics(&self) -> ARFrameSemantics

The type of semantic understanding to provide with each frame.

Use the supportsFrameSemantics class method to check if the configuration type you intend to run supports the set of frame semantics. For example, when running a session with a configuration of type ARWorldTrackingConfiguration one would need to use +[ ARWorldTrackingConfiguration supportsFrameSemantics:] to perform said check. An exception is thrown if the option is not supported. Defaults to ARFrameSemanticNone.

See: ARFrameSemantics

See: +[ARConfiguration supportsFrameSemantics:]

pub unsafe fn setFrameSemantics(&self, frame_semantics: ARFrameSemantics)

Setter for frameSemantics.

pub unsafe fn videoHDRAllowed(&self) -> bool

Whether HDR capturing is allowed if the current video format supports it. Defaults to NO.

pub unsafe fn setVideoHDRAllowed(&self, video_hdr_allowed: bool)

Setter for videoHDRAllowed.

Methods from Deref<Target = NSObject>

pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>

pub fn class(&self) -> &'static AnyClass

Dynamically find the class of this object.

Panics

May panic if the object is invalid (which may be the case for objects returned from unavailable init/new methods).

Example

Check that an instance of NSObject has the precise class NSObject.

use objc2::ClassType;
use objc2::runtime::NSObject;

let obj = NSObject::new();
assert_eq!(obj.class(), NSObject::class());

pub unsafe fn get_ivar<T>(&self, name: &str) -> &T

where T: Encode,

👎Deprecated: this is difficult to use correctly, use Ivar::load instead.

Use Ivar::load instead.

Safety

The object must have an instance variable with the given name, and it must be of type T.

See Ivar::load_ptr for details surrounding this.

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: DowncastTarget,

Attempt to downcast the object to a class of type T.

This is the reference-variant. Use Retained::downcast if you want to convert a retained object to another type.

Mutable classes

Some classes have immutable and mutable variants, such as NSString and NSMutableString.

When some Objective-C API signature says it gives you an immutable class, it generally expects you to not mutate that, even though it may technically be mutable “under the hood”.

So using this method to convert a NSString to a NSMutableString, while not unsound, is generally frowned upon unless you created the string yourself, or the API explicitly documents the string to be mutable.

See Apple’s documentation on mutability and on isKindOfClass: for more details.

Generic classes

Objective-C generics are called “lightweight generics”, and that’s because they aren’t exposed in the runtime. This makes it impossible to safely downcast to generic collections, so this is disallowed by this method.

You can, however, safely downcast to generic collections where all the type-parameters are AnyObject.

Panics

This works internally by calling isKindOfClass:. That means that the object must have the instance method of that name, and an exception will be thrown (if CoreFoundation is linked) or the process will abort if that is not the case. In the vast majority of cases, you don’t need to worry about this, since both root objects NSObject and NSProxy implement this method.

Examples

Cast an NSString back and forth from NSObject.

use objc2::rc::Retained;
use objc2_foundation::{NSObject, NSString};

let obj: Retained<NSObject> = NSString::new().into_super();
let string = obj.downcast_ref::<NSString>().unwrap();
// Or with `downcast`, if we do not need the object afterwards
let string = obj.downcast::<NSString>().unwrap();

Try (and fail) to cast an NSObject to an NSString.

use objc2_foundation::{NSObject, NSString};

let obj = NSObject::new();
assert!(obj.downcast_ref::<NSString>().is_none());

Try to cast to an array of strings.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);
// This is invalid and doesn't type check.
let arr = arr.downcast_ref::<NSArray<NSString>>();

This fails to compile, since it would require enumerating over the array to ensure that each element is of the desired type, which is a performance pitfall.

Downcast when processing each element instead.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);

for elem in arr {
    if let Some(data) = elem.downcast_ref::<NSString>() {
        // handle `data`
    }
}

Trait Implementations

impl AsRef<ARConfiguration> for ARFaceTrackingConfiguration

fn as_ref(&self) -> &ARConfiguration

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<ARFaceTrackingConfiguration> for ARFaceTrackingConfiguration

fn as_ref(&self) -> &Self

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<AnyObject> for ARFaceTrackingConfiguration

fn as_ref(&self) -> &AnyObject

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<NSObject> for ARFaceTrackingConfiguration

fn as_ref(&self) -> &NSObject

Converts this type into a shared reference of the (usually inferred) input type.

impl Borrow<ARConfiguration> for ARFaceTrackingConfiguration

fn borrow(&self) -> &ARConfiguration

Immutably borrows from an owned value.

impl Borrow<AnyObject> for ARFaceTrackingConfiguration

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for ARFaceTrackingConfiguration

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for ARFaceTrackingConfiguration

const NAME: &'static str = "ARFaceTrackingConfiguration"

The name of the Objective-C class that this type represents.

type Super = ARConfiguration

The superclass of this class.

type ThreadKind = <<ARFaceTrackingConfiguration as ClassType>::Super as ClassType>::ThreadKind

Whether the type can be used from any thread, or from only the main thread.

fn class() -> &'static AnyClass

Get a reference to the Objective-C class that this type represents.

fn as_super(&self) -> &Self::Super

Get an immutable reference to the superclass.

impl CopyingHelper for ARFaceTrackingConfiguration

Available on crate feature objc2-foundation only.

type Result = ARFaceTrackingConfiguration

The immutable counterpart of the type, or Self if the type has no immutable counterpart.

impl Debug for ARFaceTrackingConfiguration

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

Formats the value using the given formatter.

impl Deref for ARFaceTrackingConfiguration

type Target = ARConfiguration

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Hash for ARFaceTrackingConfiguration

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Message for ARFaceTrackingConfiguration

fn retain(&self) -> Retained<Self>

where Self: Sized,

Increment the reference count of the receiver.

impl NSCopying for ARFaceTrackingConfiguration

fn copy(&self) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

unsafe fn copyWithZone(&self, zone: *mut NSZone) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

impl NSObjectProtocol for ARFaceTrackingConfiguration

fn isEqual(&self, other: Option<&AnyObject>) -> bool

where Self: Sized + Message,

Check whether the object is equal to an arbitrary other object.

fn hash(&self) -> usize

where Self: Sized + Message,

An integer that can be used as a table address in a hash table structure.

fn isKindOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of the class, or one of its subclasses.

fn is_kind_of<T>(&self) -> bool

where T: ClassType, Self: Sized + Message,

👎Deprecated: use isKindOfClass directly, or cast your objects with AnyObject::downcast_ref

Check if the object is an instance of the class type, or one of its subclasses.

fn isMemberOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of a specific class, without checking subclasses.

fn respondsToSelector(&self, aSelector: Sel) -> bool

where Self: Sized + Message,

Check whether the object implements or inherits a method with the given selector.

fn conformsToProtocol(&self, aProtocol: &AnyProtocol) -> bool

where Self: Sized + Message,

Check whether the object conforms to a given protocol.

fn description(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object.

fn debugDescription(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object to use when debugging.

fn isProxy(&self) -> bool

where Self: Sized + Message,

Check whether the receiver is a subclass of the NSProxy root class instead of the usual NSObject.

fn retainCount(&self) -> usize

where Self: Sized + Message,

The reference count of the object.

impl PartialEq for ARFaceTrackingConfiguration

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RefEncode for ARFaceTrackingConfiguration

const ENCODING_REF: Encoding = <ARConfiguration as ::objc2::RefEncode>::ENCODING_REF

The Objective-C type-encoding for a reference of this type.

impl DowncastTarget for ARFaceTrackingConfiguration

impl Eq for ARFaceTrackingConfiguration