Feature Request

A feature that has been liked immensely in other programs, is the reference layer feature. The feature works in the way that if one was to set one layer as a reference layer, one could use things such as the fill tool on the layers below it, but where it would go would be affected by the reference layer. This speeds up the drawing process a lot, and it useful for coloring quickly and editing later. It is a feature that some rely heavily on in other programs, and are dissapointed to find that Photoshop doesn't have it. If there is another way to do this in Photoshop that is easy to use, please suggest.