Interface class for the rbcComputeDists kernels. More...

#include <algorithms.hpp>

Public Types
enum	Memory : uint8_t { Memory::H_IN_X, Memory::H_IN_R, Memory::H_OUT_D, Memory::D_IN_X, Memory::D_IN_R, Memory::D_OUT_D }
	Enumerates the memory objects handled by the class. More...

Public Member Functions
	RBCComputeDists (clutils::CLEnv &_env, clutils::CLEnvInfo< 1 > _info)
	Configures an OpenCL environment as specified by `_info`. More...

cl::Memory &	get (RBCComputeDists::Memory mem)
	Returns a reference to an internal memory object. More...

void	init (unsigned int _nx, unsigned int _nr, unsigned int _d=8, float _a=1.f, Staging _staging=Staging::IO)
	Configures kernel execution parameters. More...

void	write (RBCComputeDists::Memory mem=RBCComputeDists::Memory::D_IN_X, void ptr=nullptr, bool block=CL_FALSE, const std::vector< cl::Event > events=nullptr, cl::Event *event=nullptr)
	Performs a data transfer to a device buffer. More...

void *	read (RBCComputeDists::Memory mem=RBCComputeDists::Memory::H_OUT_D, bool block=CL_TRUE, const std::vector< cl::Event > events=nullptr, cl::Event event=nullptr)
	Performs a data transfer to a staging buffer. More...

void	run (const std::vector< cl::Event > events=nullptr, cl::Event event=nullptr)
	Executes the necessary kernels. More...

float	getAlpha ()
	Gets the scaling factor \( \alpha \). More...

void	setAlpha (float _a)
	Sets the scaling factor \( \alpha \). More...

template<typename period >
double	run (clutils::GPUTimer< period > &timer, const std::vector< cl::Event > *events=nullptr)
	Executes the necessary kernels. More...

Public Attributes
cl_float *	hPtrInX

cl_float *	hPtrInR

cl_float *	hPtrOutD

Detailed Description

template<KernelTypeC K = KernelTypeC::SHARED_NONE>
class cl_algo::RBC::RBCComputeDists< K >

Interface class for the rbcComputeDists kernels.

The rbcComputeDists kernels compute the distances between two sets of points in a brute force way. For more details, look at the kernel's documentation.

Note: The rbcComputeDists kernels are available in kernels/rbc_kernels.cl.; The class creates its own buffers. If you would like to provide your own buffers, call get to get references to the placeholders within the class and assign them to your buffers. You will have to do this strictly before the call to init. You can also call get (after the call to init) to get a reference to a buffer within the class and assign it to another kernel class instance further down in your task pipeline.

The following input/output OpenCL memory objects are created by a RBCComputeDists instance:

Name	Type	Placement	I/O	Use	Properties	Size
H_IN_X	Buffer	Host	I	Staging	CL_MEM_READ_WRITE	\(n_xd sizeof\ (cl\_float)\)
H_IN_R	Buffer	Host	I	Staging	CL_MEM_READ_WRITE	\(n_rd sizeof\ (cl\_float)\)
H_OUT_D	Buffer	Host	O	Staging	CL_MEM_READ_WRITE	\(n_xn_rsizeof\ (cl\_float)\)
D_IN_X	Buffer	Device	I	Processing	CL_MEM_READ_ONLY	\(n_xd sizeof\ (cl\_float)\)
D_IN_R	Buffer	Device	I	Processing	CL_MEM_READ_ONLY	\(n_rd sizeof\ (cl\_float)\)
D_OUT_D	Buffer	Device	O	Processing	CL_MEM_WRITE_ONLY	\(n_xn_rsizeof\ (cl\_float)\)

Template Parameters

K	configures the class for using one of the available kernels.

Member Enumeration Documentation

template<KernelTypeC K = KernelTypeC::SHARED_NONE>

enum cl_algo::RBC::RBCComputeDists::Memory : uint8_t

strong

Enumerates the memory objects handled by the class.

Note: H_* names refer to staging buffers on the host.; D_* names refer to buffers on the device.

Enumerator
H_IN_X	Input staging buffer.
H_IN_R	Input staging buffer.
H_OUT_D	Output staging buffer for channel R.
D_IN_X	Input buffer.
D_IN_R	Input buffer.
D_OUT_D	Output buffer for channel R.

Constructor & Destructor Documentation

template<KernelTypeC K>

cl_algo::RBC::RBCComputeDists< K >::RBCComputeDists	(	clutils::CLEnv &	_env,
		clutils::CLEnvInfo< 1 >	_info
	)

Configures an OpenCL environment as specified by _info.

Parameters

[in]	_env	opencl environment.
[in]	_info	opencl configuration. Specifies the context, queue, etc, to be used.

Member Function Documentation

template<KernelTypeC K>

cl::Memory & cl_algo::RBC::RBCComputeDists< K >::get ( RBCComputeDists< K >::Memory mem )

Returns a reference to an internal memory object.

This interface exists to allow CL memory sharing between different kernels.

Parameters

[in] mem enumeration value specifying the requested memory object.

Returns: A reference to the requested memory object.

template<KernelTypeC K>

float cl_algo::RBC::RBCComputeDists< K >::getAlpha ( )

Gets the scaling factor \( \alpha \).

Note: If the template parameter, K, has the value SHARED_NONE, SHARED_R, or SHARED_X_R, the parameter \( \alpha \) is not applicable and the value returned is \( \infty \).

Returns: The scaling factor \( \alpha \).

template<KernelTypeC K>

void cl_algo::RBC::RBCComputeDists< K >::init	(	unsigned int	_nx,
		unsigned int	_nr,
		unsigned int	_d = `8`,
		float	_a = `1.f`,
		Staging	_staging = `Staging::IO`
	)

Configures kernel execution parameters.

Sets up memory objects as necessary, and defines the kernel workspaces.

Note: If you have assigned a memory object to one member variable of the class before the call to init, then that memory will be maintained. Otherwise, a new memory object will be created.

Parameters

[in]	_nx	number of database points.
[in]	_nr	number of representative points.
[in]	_d	dimensionality of the associated points.
[in]	_a	factor scaling the results of the distance calculations for the geometric \( x_g \) and photometric \( x_p \) dimensions of the \( x\epsilon\mathbb{R}^8 \) points. That is, \( \\|x-x'\\|_2^2= f_g(a)\\|x_g-x'_g\\|_2^2+f_p(a)\\|x_p-x'_p\\|_2^2 \). This parameter is applicable when involving the "Kinect" kernels. That is, when the template parameter, `K`, gets the value `KINECT`, `KINECT_R`, or `KINECT_X_R`. For more details, take a look at `euclideanSquaredMetric8` in `kernels/rbc_kernels.cl`.
[in]	_staging	flag to indicate whether or not to instantiate the staging buffers.

template<KernelTypeC K>

void * cl_algo::RBC::RBCComputeDists< K >::read	(	RBCComputeDists< K >::Memory	mem = `RBCComputeDists< K >::Memory::H_OUT_D`,
		bool	block = `CL_TRUE`,
		const std::vector< cl::Event > *	events = `nullptr`,
		cl::Event *	event = `nullptr`
	)

Performs a data transfer to a staging buffer.

The transfer happens from a device buffer to the associated (specified) staging buffer on the host.

Parameters

[in]	mem	enumeration value specifying an output staging buffer.
[in]	block	a flag to indicate whether to perform a blocking or a non-blocking operation.
[in]	events	a wait-list of events.
[out]	event	event associated with the read operation to the staging buffer.

template<KernelTypeC K>

void cl_algo::RBC::RBCComputeDists< K >::run	(	const std::vector< cl::Event > *	events = `nullptr`,
		cl::Event *	event = `nullptr`
	)

Executes the necessary kernels.

The function call is non-blocking.

Parameters

[in]	events	a wait-list of events.
[out]	event	event associated with the kernel execution.

template<KernelTypeC K = KernelTypeC::SHARED_NONE>

template<typename period >

double cl_algo::RBC::RBCComputeDists< K >::run	(	clutils::GPUTimer< period > &	timer,
		const std::vector< cl::Event > *	events = `nullptr`
	)

inline

Executes the necessary kernels.

This run instance is used for profiling.

Parameters

[in]	timer	`GPUTimer` that does the profiling of the kernel executions.
[in]	events	a wait-list of events.

Returns: Τhe total execution time measured by the timer.

template<KernelTypeC K>

void cl_algo::RBC::RBCComputeDists< K >::setAlpha ( float _a )

Sets the scaling factor \( \alpha \).

Updates the kernel argument for the scaling factor \( \alpha \).

Note: If the template parameter, K, has the value SHARED_NONE, SHARED_R, or SHARED_X_R, the parameter \( \alpha \) is not applicable and the function has no effect.

Parameters

[in] _a scaling factor \( \alpha \).

template<KernelTypeC K>

void cl_algo::RBC::RBCComputeDists< K >::write	(	RBCComputeDists< K >::Memory	mem = `RBCComputeDists< K >::Memory::D_IN_X`,
		void *	ptr = `nullptr`,
		bool	block = `CL_FALSE`,
		const std::vector< cl::Event > *	events = `nullptr`,
		cl::Event *	event = `nullptr`
	)

Performs a data transfer to a device buffer.

The transfer happens from a staging buffer on the host to the associated (specified) device buffer.

Parameters

[in]	mem	enumeration value specifying an input device buffer.
[in]	ptr	a pointer to an array holding input data. If not NULL, the data from `ptr` will be copied to the associated staging buffer.
[in]	block	a flag to indicate whether to perform a blocking or a non-blocking operation.
[in]	events	a wait-list of events.
[out]	event	event associated with the write operation to the device buffer.