Struct MPSImageFindKeypoints 

pub struct MPSImageFindKeypoints { /* private fields */ }

Available on crate features MPSCore and MPSImageKeypoint and MPSKernel only.

The MPSImageFindKeypoints kernel is used to find a list of keypoints whose values are >= minimumPixelThresholdValue in MPSImageKeypointRangeInfo. The keypoints are generated for a specified region in the image. The pixel format of the source image must be MTLPixelFormatR8Unorm.

See also Apple’s documentation

Implementations

impl MPSImageFindKeypoints

pub unsafe fn keypointRangeInfo(&self) -> MPSImageKeypointRangeInfo

Available on crate feature MPSImage only.

Return a structure describing the keypoint range info

Returns a MPSImageKeypointRangeInfo structure

pub unsafe fn initWithDevice_info( this: Allocated<Self>, device: &ProtocolObject<dyn MTLDevice>, info: NonNull<MPSImageKeypointRangeInfo>, ) -> Retained<Self>

Available on crate feature MPSImage only.

Specifies information to find keypoints in an image.

Parameter device: The device the filter will run on

Parameter info: Pointer to the MPSImageKeypointRangeInfo struct

Returns: A valid MPSImageFindKeypoints object or nil, if failure.

Safety

info must be a valid pointer.

pub unsafe fn initWithDevice( this: Allocated<Self>, device: &ProtocolObject<dyn MTLDevice>, ) -> Retained<Self>

Available on crate feature MPSImage only.

pub unsafe fn initWithCoder_device( this: Allocated<Self>, a_decoder: &NSCoder, device: &ProtocolObject<dyn MTLDevice>, ) -> Option<Retained<Self>>

Available on crate feature MPSImage only.

NSSecureCoding compatability

While the standard NSSecureCoding/NSCoding method -initWithCoder: should work, since the file can’t know which device your data is allocated on, we have to guess and may guess incorrectly. To avoid that problem, use initWithCoder:device instead.

Parameter aDecoder: The NSCoder subclass with your serialized MPSKernel

Parameter device: The MTLDevice on which to make the MPSKernel

Returns: A new MPSKernel object, or nil if failure.

Safety

a_decoder possibly has further requirements.

pub unsafe fn encodeToCommandBuffer_sourceTexture_regions_numberOfRegions_keypointCountBuffer_keypointCountBufferOffset_keypointDataBuffer_keypointDataBufferOffset( &self, command_buffer: &ProtocolObject<dyn MTLCommandBuffer>, source: &ProtocolObject<dyn MTLTexture>, regions: NonNull<MTLRegion>, number_of_regions: NSUInteger, keypoint_count_buffer: &ProtocolObject<dyn MTLBuffer>, keypoint_count_buffer_offset: NSUInteger, keypoint_data_buffer: &ProtocolObject<dyn MTLBuffer>, keypoint_data_buffer_offset: NSUInteger, )

Available on crate feature MPSImage only.

Encode the filter to a command buffer using a MTLComputeCommandEncoder.

The filter will not begin to execute until after the command buffer has been enqueued and committed.

Parameter commandBuffer: A valid MTLCommandBuffer.

Parameter source: A valid MTLTexture containing the source image for the filter.

Parameter regions: An array of rectangles that describe regions in the image. The list of keypoints is generated for each individual rectangle specifed.

Parameter keypointCountBuffer: The list of keypoints for each specified region

Parameter keypointCountBufferOffset: Byte offset into keypointCountBufferOffset buffer at which to write the keypoint results. Must be a multiple of 32 bytes.

Parameter keypointDataBuffer: A valid MTLBuffer to receive the keypoint data results for each rectangle. The keypoint data for keypoints in each rectangle are stored consecutively. The keypoint data for each rectangle starts at the following offset: MPSImageKeypointRangeInfo.maximumKeyPoints * rectangle index

Parameter keypointDataBufferOffset: Byte offset into keypointData buffer at which to write the keypoint results. Must be a multiple of 32 bytes.

Safety

• source may need to be synchronized.
• source may be unretained, you must ensure it is kept alive while in use.
• regions must be a valid pointer.
• keypoint_count_buffer may need to be synchronized.
• keypoint_count_buffer may be unretained, you must ensure it is kept alive while in use.
• keypoint_count_buffer contents should be of the correct type.
• keypoint_data_buffer may need to be synchronized.
• keypoint_data_buffer may be unretained, you must ensure it is kept alive while in use.
• keypoint_data_buffer contents should be of the correct type.

impl MPSImageFindKeypoints

Methods declared on superclass MPSKernel.

pub unsafe fn initWithCoder( this: Allocated<Self>, a_decoder: &NSCoder, ) -> Option<Retained<Self>>

Available on crate feature MPSImage only.

Called by NSCoder to decode MPSKernels

This isn’t the right interface to decode a MPSKernel, but it is the one that NSCoder uses. To enable your NSCoder (e.g. NSKeyedUnarchiver) to set which device to use extend the object to adopt the MPSDeviceProvider protocol. Otherwise, the Metal system default device will be used.

Safety

a_decoder possibly has further requirements.

impl MPSImageFindKeypoints

Methods declared on superclass NSObject.

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

Available on crate feature MPSImage only.

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

Available on crate feature MPSImage only.

Methods from Deref<Target = MPSKernel>

pub unsafe fn options(&self) -> MPSKernelOptions

Available on crate feature MPSCoreTypes only.

The set of options used to run the kernel. subsubsection_options

pub unsafe fn setOptions(&self, options: MPSKernelOptions)

Available on crate feature MPSCoreTypes only.

Setter for options.

pub unsafe fn device(&self) -> Retained<ProtocolObject<dyn MTLDevice>>

The device on which the kernel will be used

pub unsafe fn label(&self) -> Option<Retained<NSString>>

A string to help identify this object.

pub unsafe fn setLabel(&self, label: Option<&NSString>)

Setter for label.

This is copied when set.

pub unsafe fn copyWithZone_device( &self, zone: *mut NSZone, device: Option<&ProtocolObject<dyn MTLDevice>>, ) -> Retained<Self>

Make a copy of this MPSKernel for a new device

-copyWithZone: will call this API to make a copy of the MPSKernel on the same device. This interface may also be called directly to make a copy of the MPSKernel on a new device. Typically, the same MPSKernels should not be used to encode kernels on multiple command buffers from multiple threads. Many MPSKernels have mutable properties that might be changed by the other thread while this one is trying to encode. If you need to use a MPSKernel from multiple threads make a copy of it for each additional thread using -copyWithZone: or -copyWithZone:device:

Parameter zone: The NSZone in which to allocate the object

Parameter device: The device for the new MPSKernel. If nil, then use self.device.

Returns: a pointer to a copy of this MPSKernel. This will fail, returning nil if the device is not supported. Devices must be MTLFeatureSet_iOS_GPUFamily2_v1 or later.

Safety

zone must be a valid pointer or null.

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<AnyObject> for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn as_ref(&self) -> &AnyObject

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

impl AsRef<MPSImageFindKeypoints> for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn as_ref(&self) -> &Self

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

impl AsRef<MPSKernel> for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn as_ref(&self) -> &MPSKernel

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

impl AsRef<NSObject> for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn as_ref(&self) -> &NSObject

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

impl Borrow<AnyObject> for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<MPSKernel> for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn borrow(&self) -> &MPSKernel

Immutably borrows from an owned value.

impl Borrow<NSObject> for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for MPSImageFindKeypoints

Available on crate feature MPSImage only.

const NAME: &'static str = "MPSImageFindKeypoints"

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

type Super = MPSKernel

The superclass of this class.

type ThreadKind = <<MPSImageFindKeypoints 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 MPSImageFindKeypoints

Available on crate feature MPSImage only.

type Result = MPSImageFindKeypoints

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

impl Debug for MPSImageFindKeypoints

Available on crate feature MPSImage only.

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

Formats the value using the given formatter.

impl Deref for MPSImageFindKeypoints

Available on crate feature MPSImage only.

type Target = MPSKernel

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for MPSImageFindKeypoints

Available on crate feature MPSImage only.

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 MPSImageFindKeypoints

Available on crate feature MPSImage only.

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSCoding for MPSImageFindKeypoints

Available on crate feature MPSImage only.

unsafe fn encodeWithCoder(&self, coder: &NSCoder)

where Self: Sized + Message,

Safety

unsafe fn initWithCoder( this: Allocated<Self>, coder: &NSCoder, ) -> Option<Retained<Self>>

where Self: Sized + Message,

Safety

impl NSCopying for MPSImageFindKeypoints

Available on crate feature MPSImage only.

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 MPSImageFindKeypoints

Available on crate feature MPSImage only.

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 NSSecureCoding for MPSImageFindKeypoints

Available on crate feature MPSImage only.

fn supportsSecureCoding() -> bool

where Self: Sized + ClassType,

impl PartialEq for MPSImageFindKeypoints

Available on crate feature MPSImage only.

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 MPSImageFindKeypoints

Available on crate feature MPSImage only.

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

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

impl DowncastTarget for MPSImageFindKeypoints

Available on crate feature MPSImage only.

impl Eq for MPSImageFindKeypoints

Available on crate feature MPSImage only.