In a new material, put a Reflect/Refract map into any slot (doesn't matter where). Check the 'from file' button, so it enables the render bottom panels. Size = each view's render size. If you have any atmospheric effects set up, use the values there, or you can have it pull from a camera.
Click on the To File to tell it where to dump the files and what name to give them. then click the 'pick object and render maps button' and click on a camera or object you want it to render from (this'd be your origin point) and you are done.