Module: RGeo::Cartesian::ValidOpHelpers

Includes:
ImplHelper::ValidOpHelpers
Defined in:
lib/rgeo/cartesian/valid_op.rb

Class Method Summary collapse

Methods included from ImplHelper::ValidOpHelpers

check_consistent_area_mp, check_holes_in_shell, check_holes_not_nested, check_invalid_coordinate, check_no_self_intersecting_rings, check_no_self_intersections, check_shells_not_nested

Class Method Details

.check_connected_interiors(poly) ⇒ String

Checks that the interior of a polygon is connected.

Process to do this is to walk around an interior cycle of the exterior shell in the polygon’s geometry graph. It will keep track of all the nodes it visited and if that set is a superset of the coordinates in the exterior_ring, the interior is connected, otherwise it is split somewhere.



55
56
57
58
59
60
61
62
63
64
65
66
 
# File 'lib/rgeo/cartesian/valid_op.rb', line 55

def check_connected_interiors(poly)
  exterior_coords = poly.exterior_ring.coordinates.to_set

  visited = Set.new
  poly.send(:graph).geom_edges.first.exterior_edge.and_connected do |hedge|
    visited << hedge.origin.coordinates
  end

  return Error::DISCONNECTED_INTERIOR unless exterior_coords.subset?(visited)

  nil
end

.check_consistent_area(poly) ⇒ String

Checks that there are no invalid intersections between the components of a polygon.



26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
 
# File 'lib/rgeo/cartesian/valid_op.rb', line 26

def check_consistent_area(poly)
  # Get set of unique coords
  pts = poly.exterior_ring.coordinates.to_set
  poly.interior_rings.each do |ring|
    pts += ring.coordinates
  end
  num_points = pts.size

  # if additional nodes were added, there must be an intersection
  # through a boundary.
  return Error::SELF_INTERSECTION if poly.send(:graph).incident_edges.size > num_points

  rings = [poly.exterior_ring] + poly.interior_rings
  return Error::SELF_INTERSECTION if rings.uniq.size != rings.size

  nil
end