Add decompose for polygon

Author: Sov-trotter

src/interfaces.jl

@@ -112,6 +112,15 @@ function decompose(::Type{T}, primitive) where {T}
     return collect_with_eltype(T, primitive)
 end
 
+function decompose(::Type{P}, pol::Polygon) where {P<:AbstractPoint}
+    if isempty(pol.interiors)
+        return decompose(P, pol.exterior)
+    else
+        points = Array{Union{Point, Array}}[]
+        push!(points, decompose(P, pol.exterior), [decompose(P, pol.interiors[1]) for i in pol.interiors])
+        return points
+    end
+end
 decompose(::Type{P}, ls::LineString) where {P<:AbstractPoint} = ls.points.parent.data
 decompose_uv(primitive) = decompose(UV(), primitive)
 decompose_uvw(primitive) = decompose(UVW(), primitive)