Display Mode for Retopology

A mode is needed for retopology that both shows where the lowpoly clips through the highpoly (important to get the lowpoly right), and makes the lowpoly back faces occluded (so they don't create visual noise and make selecting mesh harder). That would be 'Show whole scene transparent option' that only works for other objects, not the one in Edit mode. Example in the image - notice that it's almost like the 'Show whole scene transparent option', but the front faces of the object currently in Edit Mode occlude the mesh from that object that is behind them, just like when 'Show whole scene transparent option' is off - so it's a hybrid view.