Is there any proper way to access the low level OpenGL objects of VTK in order to modify them from a CUDA/OpenCL kernel using the openGL-CUDA/OpenCL interoperability feature?

Specifically, I would want to get the GLuint (or unsigned int) member from vtkOpenGLGPUVolumeRayCastMapper that points to the Opengl 3D Texture object where the dataset is stored, in order to bind it to a CUDA Surface to be able to access and modify its values from a CUDA kernel implemented by me.

For further information, the process that I need to follow is explained here: http://rauwendaal.net/2011/12/02/writing-to-3d-opengl-textures-in-cuda-4-1-with-3d-surface-writes/ where the texID object used there (in Steps 1 and 2) is the equivalent to what I want to retrieve from VTK.

At a first look at the vtkOpenGLGPUVolumeRayCastMapper functions, I don't find an easy way to do this, rather than maybe creating a vtkGPUVolumeRayCastMapper subclass, but even in that case I am not sure what should I modify exactly, since I guess that some other members depend on the 3D Texture values, and should be also updated after modifying it.

So, do you know some way to do this?

Lots of thanks.