cl_int
clGetDeviceIDsFromD3D11KHR
(
| cl_platform_id platform, |
cl_d3d11_device_source_khr d3d_device_source, | |
void *d3d_object, | |
cl_d3d11_device_set_khr d3d_device_set, | |
cl_uint num_entries, | |
cl_device_id *devices, | |
cl_uint *num_devices) |
platform
Refers to the platform ID returned by clGetPlatformIDs.
d3d_device_source
Specifies the type of d3d_object
and may be one of the following:.
cl_d3d_device_source_khr | Type of d3d_object |
---|---|
CL_D3D11_DEVICE_KHR
|
ID3D11Device * |
CL_D3D11_DXGI_ADAPTER_KHR
|
IDXGIAdapter * |
d3d_object
Specifies the object whose corresponding OpenCL devices are being queried. The type of
d3d_object
must be as specified in the table above.
d3d_device_set
Specifies the set of devices to return, and must be one of the following:
cl_d3d_device_set_khr | Devices returned in devices |
---|---|
CL_PREFERRED_DEVICES_FOR_D3D11_KHR
|
The OpenCL devices associated with the specified Direct3D object. |
CL_ALL_DEVICES_FOR_D3D11_KHR
|
All OpenCL devices which may interoperate with the specified Direct3D object. Performance of sharing data on these devices may be considerably less than on the preferred devices. |
num_entries
The number of cl_device_id entries that can be added to
devices
. If devices
is not NULL, the
num_entries
must be greater than zero.
devices
Returns a list of OpenCL devices found. The cl_device_id values
returned in devices
can be used to identify a specific
OpenCL device. If devices
is NULL, this argument is
ignored. The number of OpenCL devices returned is the mininum of the value
specified by num_entries
and the number of OpenCL devices
corresponding to d3d_object
.
num_devices
Returns the number of OpenCL devices available that correspond to
d3d_object
. If num_devices
is NULL,
this argument is ignored.
The OpenCL devices corresponding to a Direct3D 11 device may be queried. The OpenCL devices corresponding to a DXGI adapter may also be queried. The OpenCL devices corresponding to a Direct3D 11 device will be a subset of the OpenCL devices corresponding to the DXGI adapter against which the Direct3D 11 device was created.
General information about sharing memory objects with Direct3D 11 follows.
The goal of this extension is to provide
interoperability between OpenCL and Direct3D 11. This is designed to function analogously
to the OpenGL interoperability. If this extension is
supported by an implementation, the string
cl_khr_d3d11_sharing
will be present in the
CL_PLATFORM_EXTENSIONS
or CL_DEVICE_EXTENSIONS
string described in the table of allowed
values for param_name
for
clGetDeviceInfo.
As currently proposed the interfaces for this extension would be provided in
cl_d3d11.h
.
This section discusses OpenCL functions that allow applications to use Direct3D 11 resources as OpenCL memory objects. This allows efficient sharing of data between OpenCL and Direct3D 11. The OpenCL API may be used to execute kernels that read and/or write memory objects that are also Direct3D 11 resources. An OpenCL image object may be created from a Direct3D 11 texture resource. An OpenCL buffer object may be created from a Direct3D 11 buffer resource. OpenCL memory objects may be created from Direct3D 11 objects if and only if the OpenCL context has been created from a Direct3D 11 device.
An OpenCL memory object created from a Direct3D 11 resource remains valid as long as the corresponding Direct3D 11 resource has not been deleted. If the Direct3D 11 resource is deleted through the Direct3D 11 API, subsequent use of the OpenCL memory object will result in undefined behavior, including but not limited to possible OpenCL errors, data corruption, and program termination.
The successful creation of a
cl_context against a Direct3D 11 device specified via the context create parameter
CL_CONTEXT_D3D11_DEVICE_KHR
will increment the internal Direct3D
reference count on the specified Direct3D 11 device. The internal Direct3D reference
count on that Direct3D 11 device will be decremented when the OpenCL reference count on
the returned OpenCL context drops to zero.
The OpenCL context and corresponding command-queues are dependent on the existence of the Direct3D 11 device from which the OpenCL context was created. If the Direct3D 11 device is deleted through the Direct3D 11 API, subsequent use of the OpenCL context will result in undefined behavior, including but not limited to possible OpenCL errors, data corruption, and program termination.
Properties of Direct3D 11 objects may be queried
using clGetMemObjectInfo
and clGetImageInfo
with param_name
CL_MEM_D3D11_RESOURCE_KHR
and
CL_IMAGE_D3D11_SUBRESOURCE_KHR
as described for clGetImageInfo and in the information
below about accessing mapped regions of a memory object.
This section describes the behavior of OpenCL commands that access mapped regions of a memory object.
The contents of the region of a memory object and associated memory objects
(sub-buffer objects or 1D image buffer objects that overlap this region) mapped
for writing (i.e. CL_MAP_WRITE
or
CL_MAP_WRITE_INVALIDATE_REGION
is set in map_flags
argument to clEnqueueMapBuffer
or clEnqueueMapImage) are
considered to be undefined until this region is unmapped.
Multiple commands in command-queues can map a region or overlapping regions of a memory
object and associated memory objects (sub-buffer objects or 1D image buffer objects that
overlap this region) for reading (i.e. map_flags
= CL_MAP_READ
).
The contents of the regions of a memory object mapped for reading can also be read by kernels
and other OpenCL commands (such as
clEnqueueCopyBuffer) executing on a device(s).
Mapping (and unmapping) overlapped regions in a memory object and/or associated memory
objects (sub-buffer objects or 1D image buffer objects that overlap this region) for writing
is an error and will result in CL_INVALID_OPERATION
error returned by
clEnqueueMapBuffer
or clEnqueueMapImage.
If a memory object is currently mapped for writing, the application must ensure that the memory object is unmapped before any enqueued kernels or commands that read from or write to this memory object or any of its associated memory objects (sub-buffer or 1D image buffer objects) or its parent object (if the memory object is a sub-buffer or 1D image buffer object) begin execution; otherwise the behavior is undefined.
If a memory object is currently mapped for reading, the application must ensure that the memory object is unmapped before any enqueued kernels or commands that write to this memory object or any of its associated memory objects (sub-buffer or 1D image buffer objects) or its parent object (if the memory object is a sub-buffer or 1D image buffer object) begin execution; otherwise the behavior is undefined.
Accessing the contents of the memory region referred to by the mapped pointer that has been unmapped is undefined.
The mapped pointer returned by
clEnqueueMapBuffer
or clEnqueueMapImage can be used as
ptr
argument value to
clEnqueueReadBuffer,
clEnqueueWriteBuffer,
clEnqueueReadBufferRect,
clEnqueueWriteBufferRect,
clEnqueueReadImage, and
clEnqueueWriteImage,
provided the rules described above are adhered to.
Returns CL_SUCCESS if the function is executed successfully. Otherwise it may return:
platform
is not
a valid platform.
d3d_device_source
is not a valid value, d3d_device_set
is not a valid value,
num_entries
is equal to zero and devices
is
not NULL, or if both num_devices
and devices
are NULL.
d3d_object
were found.
cl_khr_d3d11_sharing, clCreateFromD3D11BufferKHR, clCreateFromD3D11Texture2DKHR, clCreateFromD3D11Texture3DKHR, clEnqueueAcquireD3D11ObjectsKHR, clEnqueueReleaseD3D11ObjectsKHR