Struct MPSMatrix 

pub struct MPSMatrix { /* private fields */ }

Available on crate feature MPSMatrix only.

Dependencies: This depends on Metal.framework

A MPSMatrix object describes a set of 2-dimensional arrays of data and provides storage for its values. MPSMatrix objects serve as inputs and outputs of MPSMatrixKernel objects.

Implementation note: A MPSMatrix object maintains its internal storage using a MTLBuffer object and thus the same rules for maintaining coherency of a MTLBuffer’s data between CPU memory and GPU memory apply to a MPSMatrix. An MPSMatrix object’s data refers to an array of matrices. Data is assumed to be ordered by matrix first, followed by row, followed by column.

For example, index [i,j] of the k’th matrix of an MPSMatrix is located at byte offset: k * matrixBytes + i * rowBytes + j * sizeof(dataType)

Where matrixBytes is a multiple of rowBytes at least equal to rows * rowBytes.

See also Apple’s documentation

Implementations

impl MPSMatrix

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

Available on crate feature MPSCore only.

The device on which the MPSMatrix will be used.

pub unsafe fn rows(&self) -> NSUInteger

Available on crate feature MPSCore only.

The number of rows in a matrix in the MPSMatrix.

pub unsafe fn columns(&self) -> NSUInteger

Available on crate feature MPSCore only.

The number of columns in a matrix in the MPSMatrix.

pub unsafe fn matrices(&self) -> NSUInteger

Available on crate feature MPSCore only.

The number of matrices in the MPSMatrix.

pub unsafe fn dataType(&self) -> MPSDataType

Available on crate features MPSCore and MPSCoreTypes only.

The type of the MPSMatrix data.

pub unsafe fn rowBytes(&self) -> NSUInteger

Available on crate feature MPSCore only.

The stride, in bytes, between corresponding elements of consecutive rows.

pub unsafe fn matrixBytes(&self) -> NSUInteger

Available on crate feature MPSCore only.

The stride, in bytes, between corresponding elements of consecutive matrices.

pub unsafe fn offset(&self) -> NSUInteger

Available on crate feature MPSCore only.

Byte-offset to the buffer where the matrix data begins - see initWithBuffer:offset: descriptor: .

pub unsafe fn data(&self) -> Retained<ProtocolObject<dyn MTLBuffer>>

Available on crate feature MPSCore only.

An MTLBuffer to store the data.

pub unsafe fn initWithBuffer_descriptor( this: Allocated<Self>, buffer: &ProtocolObject<dyn MTLBuffer>, descriptor: &MPSMatrixDescriptor, ) -> Retained<Self>

Available on crate feature MPSCore only.

Initialize a MPSMatrix object with a MTLBuffer.

Parameter buffer: The MTLBuffer object which contains the data to use for the MPSMatrix. May not be NULL.

Parameter descriptor: The MPSMatrixDescriptor. May not be NULL.

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

This function returns a MPSMatrix object which uses the supplied MTLBuffer. The dimensions and stride of the matrix are specified by the MPSMatrixDescriptor object.

The provided MTLBuffer must have enough storage to hold

(descriptor.matrices-1) * descriptor.matrixBytes + (descriptor.rows-1) * descriptor.rowBytes + descriptor.columns * (element size) bytes.

Safety

• buffer may need to be synchronized.
• buffer may be unretained, you must ensure it is kept alive while in use.
• buffer contents should be of the correct type.

pub unsafe fn initWithBuffer_offset_descriptor( this: Allocated<Self>, buffer: &ProtocolObject<dyn MTLBuffer>, offset: NSUInteger, descriptor: &MPSMatrixDescriptor, ) -> Retained<Self>

Available on crate feature MPSCore only.

Initialize a MPSMatrix object with a MTLBuffer at a given offset.

Parameter buffer: The MTLBuffer object which contains the data to use for the MPSMatrix. May not be NULL.

Parameter offset: The offset, in bytes, into the buffer at which the data begins.

Parameter descriptor: The MPSMatrixDescriptor describing the shape of the matrix.

Safety

• buffer may need to be synchronized.
• buffer may be unretained, you must ensure it is kept alive while in use.
• buffer contents should be of the correct type.

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

Available on crate feature MPSCore only.

Initialize a MPSMatrix object with a descriptor. Allocate the buffer.

Parameter device: The device with which it will be used

Parameter descriptor: The shape and style of the matrix

Returns: A valid MPSMatrix object or nil

The matrix object will be created, but the storage to hold the matrix data will only be allocated when it is needed, typically when the data property is invoked. In conjunction with -resourceSize, this will allow you to estimate storage needs without actually creating the backing store for the matrix.

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

Available on crate feature MPSCore only.

pub unsafe fn synchronizeOnCommandBuffer( &self, command_buffer: &ProtocolObject<dyn MTLCommandBuffer>, )

Available on crate feature MPSCore only.

Flush the underlying MTLBuffer from the device’s caches, and invalidate any CPU caches if needed.

This will call [id <MTLBlitEncoder

synchronizeResource: ] on the matrix’s MTLBuffer, if any. This is necessary for all MTLStorageModeManaged resources. For other resources, including temporary resources (these are all MTLStorageModePrivate), and buffers that have not yet been allocated, nothing is done. It is more efficient to use this method than to attempt to do this yourself with the data property.

Parameter commandBuffer: The commandbuffer on which to synchronize

pub unsafe fn resourceSize(&self) -> NSUInteger

Available on crate feature MPSCore only.

Get the number of bytes used to allocate underyling MTLResources

This is the size of the backing store of underlying MTLResources. It does not include all storage used by the object, for example the storage used to hold the MPSMatrix instantiation and MTLBuffer is not included. It only measures the size of the allocation used to hold the matrix data in the buffer. This value is subject to change between different devices and operating systems.

Except when -initWithBuffer:descriptor: is used, most MPSMatrixes are allocated without a backing store. The backing store is allocated lazily when it is needed, typically when the .texture property is called. Consequently, in most cases, it should be inexpensive to make a MPSImage to see how much memory it will need, and release it if it is too large.

This method may fail in certain circumstances, such as when the MPSImage is created with -initWithTexture:featureChannels:. In such cases, 0 will be returned.

impl MPSMatrix

Methods declared on superclass NSObject.

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

Available on crate feature MPSCore only.

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 MPSMatrix

Available on crate feature MPSCore only.

fn as_ref(&self) -> &AnyObject

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

impl AsRef<MPSMatrix> for MPSMatrix

Available on crate feature MPSCore only.

fn as_ref(&self) -> &Self

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

impl AsRef<MPSMatrix> for MPSTemporaryMatrix

Available on crate feature MPSCore only.

fn as_ref(&self) -> &MPSMatrix

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

impl AsRef<NSObject> for MPSMatrix

Available on crate feature MPSCore only.

fn as_ref(&self) -> &NSObject

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

impl Borrow<AnyObject> for MPSMatrix

Available on crate feature MPSCore only.

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<MPSMatrix> for MPSTemporaryMatrix

Available on crate feature MPSCore only.

fn borrow(&self) -> &MPSMatrix

Immutably borrows from an owned value.

impl Borrow<NSObject> for MPSMatrix

Available on crate feature MPSCore only.

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for MPSMatrix

Available on crate feature MPSCore only.

const NAME: &'static str = "MPSMatrix"

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

type Super = NSObject

The superclass of this class.

type ThreadKind = <<MPSMatrix 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 Debug for MPSMatrix

Available on crate feature MPSCore only.

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

Formats the value using the given formatter.

impl Deref for MPSMatrix

Available on crate feature MPSCore only.

type Target = NSObject

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for MPSMatrix

Available on crate feature MPSCore 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 MPSMatrix

Available on crate feature MPSCore only.

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSObjectProtocol for MPSMatrix

Available on crate feature MPSCore 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 PartialEq for MPSMatrix

Available on crate feature MPSCore 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 MPSMatrix

Available on crate feature MPSCore only.

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

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

impl DowncastTarget for MPSMatrix

Available on crate feature MPSCore only.

impl Eq for MPSMatrix

Available on crate feature MPSCore only.