Setting up OpenGL/Cuda interop in Windows

I am writing a DLL that needs to do some work in Cuda 3.2 and some work in OpenGL. OpenGL will render some grayscale images that my Cuda code needs to read in and modify, and then give back to OpenGL as开发者_高级运维 a texture. I believe I need to create PBOs to do that. I have done some basic OpenGL stuff before but never worked with extensions, and that's where my problem is - I've been searching for 2 days and so far haven't been able to find a working example, despite wading through pages and pages of code. None of the samples I've tried work (and I'm sure my vid card will support it, being a GTX470)

Some specific questions:

1. I installed the nvidia opengl sdk. Should I be using glew.h and wglew.h to access the extensions?

2. My DLL does not have any UI - do I need to create a hidden window or is there an easier way to create an off-screen rendering context?

3. Can I create a grayscale PBO by using GL_RED_8UI format? Will both cuda and gl be happy with that? I read the opengl interop section in the cuda programming manual and it said GL_RGBA_8UI was only usable by pixel shaders because it was an OpenGL 3.0 feature, but I didn't know if that applied to a 1-channel format. 1 channel float would also work for my purposes.

4. I thought this would be fairly easy to do - does it really require hundreds of lines of code?

Edit:

I have code to create an OpenGL context attached to a HBITMAP. Should I create a bitmap-rendering context and then try to attach a PBO to that? Or will that slow me down by also rendering to CPU memory? Is it better to create an invisible window and attach the PBO to that? Also, does the pixel format of my PBO have to match the window/bitmap? What about the dimensions?

Thanks,

Alex

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There's actually an example of how to use OpenGL and CUDA together. Look at the SimpleGL example.

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You may want to take a look at this example:

https://github.com/nvpro-samples/gl_cuda_interop_pingpong_st