Selective Grid

At simplest level the ability to show or hide the grid differently for forground and background would be useful. i.e grid shows on land but not on sea, or shows inside a building plan but not on the back ground behind the plan. e.g.

Could we add grid as a Fill texture for PT2? That would permit using different sizes (for elevation), as well as delimiting where it was visible on a map (including hiding it above areas of the BG/FG). That would make this an Art request instead of a Feature request