Hello. It's a silly question, I guess, but still: is there any way to access objects of OpenGL world from OpenCL code (light position for example)? All that I can touch are just VBOs and textures. What about other things and properties?
yes it is possible. it is called OpenGL/OpenCL interoperability when you can acess GL buffers as memory buffer from OpenCL and GL textures as images in CL.
CL-GL interop is described in the OpenCL Extensions PDF. The main spec delegates that section to this supplement.
So, Please check http://www.khronos.org/registry/cl/specs/opencl-1.2-extensions.pdf
I know about buffers and images, but what about other OpenGL objects? Lights, for instance? I just try to control my OpenGL-world by OpenCL only, achieving maximum independence from CPU performance.
no this is not possible. even OpenCL is dependent o CPU performance.