You cannot rely on a straight reading from an exposure meter when photographing very white buildings. The meter will normally want to underexpose so a little compensation is needed, especially in bright, sunny weather. The clear whiteness of the lighthouse compound and the contrasting lines within it add up to a highly graphic rendering and a composition of geometric divisions.
This is the foghorn at Nash Point on the Glamorgan coast. I was a little uncertain as I took this. Past experience suggested that configuring a circle into a square was unlikely to make a satisfying composition, but then I thought that the triangular layers beneath it might help give it some solidity in space. Square, ellipse, triangle - what's not to like!