6.31. OpenGL Interoperability

This section describes the OpenGL interoperability functions of the low-level CUDA driver application programming interface.

Note that mapping of OpenGL resources is performed with the graphics API agnostic, resource mapping interface described in Graphics Interoperability.

Enumerations

CUGLDeviceList: CUDA devices corresponding to an OpenGL device.

Functions

CUresult cuGLGetDevices(unsigned int *pCudaDeviceCount, CUdevice *pCudaDevices, unsigned int cudaDeviceCount, CUGLDeviceList deviceList): Gets the CUDA devices associated with the current OpenGL context.
CUresult cuGraphicsGLRegisterBuffer(CUgraphicsResource *pCudaResource, GLuint buffer, unsigned int Flags): Registers an OpenGL buffer object.
CUresult cuGraphicsGLRegisterImage(CUgraphicsResource *pCudaResource, GLuint image, GLenum target, unsigned int Flags): Register an OpenGL texture or renderbuffer object.
CUresult cuWGLGetDevice(CUdevice *pDevice, HGPUNV hGpu): Gets the CUDA device associated with hGpu.

APIs

OpenGL Interoperability [DEPRECATED]: This section describes deprecated OpenGL interoperability functionality.

Typedefs

HGPUNV

6.31.2. Enumerations

enum CUGLDeviceList

CUDA devices corresponding to an OpenGL device.

Values:

enumerator CU_GL_DEVICE_LIST_ALL: The CUDA devices for all GPUs used by the current OpenGL context.

enumerator CU_GL_DEVICE_LIST_CURRENT_FRAME: The CUDA devices for the GPUs used by the current OpenGL context in its currently rendering frame.

enumerator CU_GL_DEVICE_LIST_NEXT_FRAME: The CUDA devices for the GPUs to be used by the current OpenGL context in the next frame.

6.31.3. Functions

CUresult cuGLGetDevices(unsigned int *pCudaDeviceCount, CUdevice *pCudaDevices, unsigned int cudaDeviceCount, CUGLDeviceList deviceList)

Gets the CUDA devices associated with the current OpenGL context.

Returns in *pCudaDeviceCount the number of CUDA-compatible devices corresponding to the current OpenGL context. Also returns in *pCudaDevices at most cudaDeviceCount of the CUDA-compatible devices corresponding to the current OpenGL context. If any of the GPUs being used by the current OpenGL context are not CUDA capable then the call will return CUDA_ERROR_NO_DEVICE.

The deviceList argument may be any of the following:

CU_GL_DEVICE_LIST_ALL: Query all devices used by the current OpenGL context.
CU_GL_DEVICE_LIST_CURRENT_FRAME: Query the devices used by the current OpenGL context to render the current frame (in SLI).
CU_GL_DEVICE_LIST_NEXT_FRAME: Query the devices used by the current OpenGL context to render the next frame (in SLI). Note that this is a prediction, it can’t be guaranteed that this is correct in all cases.

See also

cuWGLGetDevice, ::cudaGLGetDevices

Note

Note that this function may also return error codes from previous, asynchronous launches.

Parameters

pCudaDeviceCount – - Returned number of CUDA devices.
pCudaDevices – - Returned CUDA devices.
cudaDeviceCount – - The size of the output device array pCudaDevices.
deviceList – - The set of devices to return.

Returns

CUDA_SUCCESS, CUDA_ERROR_NO_DEVICE, CUDA_ERROR_INVALID_VALUE, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_GRAPHICS_CONTEXT, CUDA_ERROR_OPERATING_SYSTEM

CUresult cuGraphicsGLRegisterBuffer(CUgraphicsResource *pCudaResource, GLuint buffer, unsigned int Flags)

Registers an OpenGL buffer object.

Registers the buffer object specified by buffer for access by CUDA. A handle to the registered object is returned as pCudaResource. The register flags Flags specify the intended usage, as follows:

CU_GRAPHICS_REGISTER_FLAGS_NONE: Specifies no hints about how this resource will be used. It is therefore assumed that this resource will be read from and written to by CUDA. This is the default value.
CU_GRAPHICS_REGISTER_FLAGS_READ_ONLY: Specifies that CUDA will not write to this resource.
CU_GRAPHICS_REGISTER_FLAGS_WRITE_DISCARD: Specifies that CUDA will not read from this resource and will write over the entire contents of the resource, so none of the data previously stored in the resource will be preserved.

See also

cuGraphicsUnregisterResource, cuGraphicsMapResources, cuGraphicsResourceGetMappedPointer, ::cudaGraphicsGLRegisterBuffer

Note

Note that this function may also return error codes from previous, asynchronous launches.

Parameters

pCudaResource – - Pointer to the returned object handle
buffer – - name of buffer object to be registered
Flags – - Register flags

Returns

CUDA_SUCCESS, CUDA_ERROR_INVALID_HANDLE, CUDA_ERROR_ALREADY_MAPPED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_OPERATING_SYSTEM

CUresult cuGraphicsGLRegisterImage(CUgraphicsResource *pCudaResource, GLuint image, GLenum target, unsigned int Flags)

Register an OpenGL texture or renderbuffer object.

Registers the texture or renderbuffer object specified by image

for access by CUDA.

A handle to the registered object is returned as

pCudaResource.

target must match the type of the object, and must be one of ::GL_TEXTURE_2D, ::GL_TEXTURE_RECTANGLE, ::GL_TEXTURE_CUBE_MAP, ::GL_TEXTURE_3D, ::GL_TEXTURE_2D_ARRAY, or ::GL_RENDERBUFFER.

The register flags Flags specify the intended usage, as follows:

CU_GRAPHICS_REGISTER_FLAGS_NONE: Specifies no hints about how this resource will be used. It is therefore assumed that this resource will be read from and written to by CUDA. This is the default value.
CU_GRAPHICS_REGISTER_FLAGS_READ_ONLY: Specifies that CUDA will not write to this resource.
CU_GRAPHICS_REGISTER_FLAGS_WRITE_DISCARD: Specifies that CUDA will not read from this resource and will write over the entire contents of the resource, so none of the data previously stored in the resource will be preserved.
CU_GRAPHICS_REGISTER_FLAGS_SURFACE_LDST: Specifies that CUDA will bind this resource to a surface reference.
CU_GRAPHICS_REGISTER_FLAGS_TEXTURE_GATHER: Specifies that CUDA will perform texture gather operations on this resource.

The following image formats are supported. For brevity’s sake, the list is abbreviated. For ex., {GL_R, GL_RG} X {8, 16} would expand to the following 4 formats {GL_R8, GL_R16, GL_RG8, GL_RG16} :

GL_RED, GL_RG, GL_RGBA, GL_LUMINANCE, GL_ALPHA, GL_LUMINANCE_ALPHA, GL_INTENSITY
{GL_R, GL_RG, GL_RGBA} X {8, 16, 16F, 32F, 8UI, 16UI, 32UI, 8I, 16I, 32I}
{GL_LUMINANCE, GL_ALPHA, GL_LUMINANCE_ALPHA, GL_INTENSITY} X {8, 16, 16F_ARB, 32F_ARB, 8UI_EXT, 16UI_EXT, 32UI_EXT, 8I_EXT, 16I_EXT, 32I_EXT}

The following image classes are currently disallowed:

Textures with borders
Multisampled renderbuffers

Note

Note that this function may also return error codes from previous, asynchronous launches.

Parameters

pCudaResource – - Pointer to the returned object handle
image – - name of texture or renderbuffer object to be registered
target – - Identifies the type of object specified by image
Flags – - Register flags

Returns

CUDA_SUCCESS, CUDA_ERROR_INVALID_HANDLE, CUDA_ERROR_ALREADY_MAPPED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_OPERATING_SYSTEM

CUresult cuWGLGetDevice(CUdevice *pDevice, HGPUNV hGpu)

Gets the CUDA device associated with hGpu.

Returns in *pDevice the CUDA device associated with a hGpu, if applicable.

Note

Note that this function may also return error codes from previous, asynchronous launches.

Parameters

pDevice – - Device associated with hGpu
hGpu – - Handle to a GPU, as queried via ::WGL_NV_gpu_affinity()

Returns

CUDA_SUCCESS, CUDA_ERROR_DEINITIALIZED, CUDA_ERROR_NOT_INITIALIZED, CUDA_ERROR_INVALID_CONTEXT, CUDA_ERROR_INVALID_VALUE

6.31.4. Typedefs

typedef void *HGPUNV