(Question)OpenCL forstreaming language for a game engine

I am in the process of my Game Engine, I want implement a system of streaming to create big maps or terrain so i need a system of stream to avoid overloading of memory,cpu.
For example: my terrain will be the size of 100x100km or more. and more the entities,objects,etc will need very powerfull machine to run.
I need a streaming system to avoid this. and see the more used, easy to learn is OpenCL and OpenMP(Another think is, i using OpenCL to my physics system with Bullet Engine).
So what recommend me OpenCL or OpenMP and can tell me about tips,reviews,experience,problems,Who is more difficult?. using this streaming languages ,Another think that round my head is about OpenCL is can work with CPU?. so can use that too so for example: a person don´t have a very good GPU so can use the CPU.
Also don´t there a OpenCL SDK or IDE official of Khronos Group only the company Intel,IBM,Nvidia,AMD have a SDK(Here can see more http://en.wikipedia.org/wiki/OpenCL#Ope … t_products) then exits a tools or something to programming with OpenCL and my same code can use the AMD,Nvidia Cards and CPU, if don´t exits can programming in the Nvidia SDK(Because i have Card Nvidia) and later my code can use the AMD card or need modify in SDK of AMD, later pass to have SDK of IBM to use in CPU, But using this process i complicating things and for game engine is no usefull.
Soo with OpenMP don´t have this type of problem if can´t use OpenCL.

Thanks for looking more to help me, Sorry if i wrong writing, I still learning English and don´t write very well.