campfire

power-operated solution: space is defined by the vague boundary. "The output of heat and light from a campfire is effectively zoned in concentric rings, brightness and hottest close to fire, coolest and darkest away form it, so that sleeping is an outer ring activity, and pursuits requiring vision belong to the inner rings. But at the same time, the distribution of heat is biased by the wind, and the trail of smoke renders the downwind side of the fire unappetizing, so that the concentric zoning is interrupted by other considerations of comfort or need." Reference: _ Christopher Hight, Michael Hensel and Achim Menges, Space Reader: Heterogeneous Space in Architecture, 2009, p.151. Reyner Banham, Environmental Management.