after searching a lot I cannot find a way to move a selection and to use it to copy a part of a layer.
So to be clear,
I have a layer, 1024x768, with a picture
I want to select a portion of it (eg a rectangle of 200x300), from its center and use it
I thought I could do the following, use the select tool, create a 200x300 selection, align it on the center of layer with the align tool, then Ctrl+C, create a new document, 200x300, Ctrl+V and job done!
But I cannot find a way to move my 200x300 box (because the align tool never selects my 200x300 rectangle but the whole layer) and then to use it to "capture" the center of the layer. I tried to use select > float on the same layer or on the other but it doesn't work.
Does anyone could help me with this?