anchor: love.physics.getDistance
  Returns the two closest points between two fixtures and their distance.
  distance, x1, y1, x2, y2 = love.physics.getDistance( fixture1, fixture2 )
  fixture1 Fixture The first fixture.
  fixture2 Fixture The second fixture.
  distance number The distance of the two points.
  x1 number The x-coordinate of the first point.
  y1 number The y-coordinate of the first point.
  x2 number The x-coordinate of the second point.
  y2 number The y-coordinate of the second point.