MPSTemporaryMatrix(3)  MetalPerformanceShaders.framework MPSTemporaryMatrix(3)

NAME

       MPSTemporaryMatrix

SYNOPSIS

       #import <MPSMatrixTypes.h>

       Inherits MPSMatrix.

   Instance Methods
       (nonnull instancetype) - initWithBuffer:descriptor:

   Class Methods
       (nonnull instancetype) +
           temporaryMatrixWithCommandBuffer:matrixDescriptor:
       (void) + prefetchStorageWithCommandBuffer:matrixDescriptorList:

   Properties
       NSUInteger readCount

Method Documentation

   - (nonnull instancetype) initWithBuffer: (nonnull id< MTLBuffer >)
       buffer(nonnull MPSMatrixDescriptor *) descriptor
       *** unavailable

       Reimplemented from MPSMatrix.

   + (void) prefetchStorageWithCommandBuffer: (nonnull id< MTLCommandBuffer >)
       commandBuffer(NSArray< MPSMatrixDescriptor * > *__nonnull)
       descriptorList
       Help MPS decide which allocations to make ahead of time  The buffer
       cache that underlies the MPSTemporaryMatrix can automatically allocate
       new storage as needed as you create new temporary matrices. However,
       sometimes a more global view of what you plan to make is useful for
       maximizing memory reuse to get the most efficient operation. This class
       method hints to the cache what the list of matrices will be.

       It is never necessary to call this method. It is purely a performance
       and memory optimization.

       Parameters:
           commandBuffer The command buffer on which the MPSTemporaryMatrix
           will be used
           descriptorList A NSArray of MPSMatrixDescriptor, indicating
           matrices that will be created



   + (nonnull instancetype) temporaryMatrixWithCommandBuffer: (nonnull id<
       MTLCommandBuffer >) commandBuffer(nonnull MPSMatrixDescriptor *)
       matrixDescriptor
       Initialize a MPSTemporaryMatrix for use on a MTLCommandBuffer

       Parameters:
           commandBuffer The MTLCommandBuffer on which the MPSTemporaryMatrix
           will be exclusively used
           matrixDescriptor A valid MPSMatrixDescriptor describing the
           MPSMatrix format to create

       Returns:
           A valid MPSTemporaryMatrix. The object is not managed by a
           NSAutoreleasePool. The object will be released when the command
           buffer is committed. The underlying buffer will become invalid
           before this time due to the action of the readCount property.
           Please read and understand the use of the readCount property before
           using this object.

Property Documentation

   - (NSUInteger) readCount [read],  [write],  [nonatomic],  [assign]
       The number of times a temporary matrix may be read by a MPSMatrix...
       kernel before its contents become undefined.

       MPSTemporaryMatrices must release their underlying buffers for reuse
       immediately after last use. So as to facilitate prompt convenient
       memory recycling, each time a MPSTemporaryMatrix is read by a
       MPSMatrix... -encode... method, its readCount is automatically
       decremented. When the readCount reaches 0, the underlying buffer is
       automatically made available for reuse to MPS for its own needs and for
       other MPSTemporaryMatrices prior to return from the -encode.. function.
       The contents of the buffer become undefined at this time.

       By default, the readCount is initialized to 1, indicating a matrix that
       may be overwritten any number of times, but read only once.

       You may change the readCount as desired to allow MPSMatrixKernels to
       read the MPSTemporaryMatrix additional times. However, it is an error
       to change the readCount once it is zero. It is an error to read or
       write to a MPSTemporaryMatrix with a zero readCount. You may set the
       readCount to 0 yourself to cause the underlying buffer to be returned
       to MPS. Writing to a MPSTemporaryMatrix does not adjust the readCount.

       The Metal API Validation layer will assert if a MPSTemporaryMatrix is
       deallocated with non-zero readCount to help identify cases when
       resources are not returned promptly.

Author

       Generated automatically by Doxygen for
       MetalPerformanceShaders.framework from the source code.





Version MetalPerformanceShaders-Thu2Jul 13 2017          MPSTemporaryMatrix(3)


Mac OS X 10.12.6 - Generated Wed Nov  1 05:56:10 CDT 2017