Urban planning is a rules-based game. Participants in the planning process have goals they wish to accomplish and constraints governing how their objectives can be achieved. Nowhere is this more the case than in London, where a complex series of regulations and protected sightlines have conspired to create ungainly clusters of misshapen towers. (The Shard, anyone?) Architects are already playing the planning game, but they are playing it clumsily. That, in effect, was the conclusion the Guardian’s Oliver Wainwright and Monica Ulmanu came to in their interactive visualization of the city’s future skyline (come to think of it, that also…