Defining points at real dimensions

John

Is there any tool to define patch using actual length. e.g 2m 3m. Defining patches using block number is very uncomfortable when the mesh is biased and almost impossible when unstructured mesh is used. In addition to this when simulation outputs are needed at specific point, say at x = 3m, y = 2m z = 5m. How it is possible to locate such a point using block number in case of using biased or unstructured grid?

I found the block labeling of points are only applicable in case of uniform grid, if any one knows the solution, please post your recomendations

Thanks

John