[WIP] Simplify Graph

Project.toml

@@ -4,7 +4,10 @@ authors = ["Jack Chan <[email protected]>"]
 version = "0.3.1"
 
 [deps]
+DataFrames = "a93c6f00-e57d-5684-b7b6-d8193f3e46c0"
 DataStructures = "864edb3b-99cc-5e75-8d2d-829cb0a9cfe8"
+GeoInterface = "cf35fbd7-0cd7-5166-be24-54bfbe79505f"
+GeoInterfaceRecipes = "0329782f-3d07-4b52-b9f6-d3137cf03c7a"
 Graphs = "86223c79-3864-5bf0-83f7-82e725a168b6"
 HTTP = "cd3eb016-35fb-5094-929b-558a96fad6f3"
 JSON = "682c06a0-de6a-54ab-a142-c8b1cf79cde6"
@@ -13,6 +16,7 @@ MetaGraphs = "626554b9-1ddb-594c-aa3c-2596fe9399a5"
 NearestNeighbors = "b8a86587-4115-5ab1-83bc-aa920d37bbce"
 Parameters = "d96e819e-fc66-5662-9728-84c9c7592b0a"
 QuickHeaps = "30b38841-0f52-47f8-a5f8-18d5d4064379"
+RecipesBase = "3cdcf5f2-1ef4-517c-9805-6587b60abb01"
 SimpleWeightedGraphs = "47aef6b3-ad0c-573a-a1e2-d07658019622"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 SpatialIndexing = "d4ead438-fe20-5cc5-a293-4fd39a41b74c"

example.jl

@@ -0,0 +1,38 @@
+using LightOSM, Plots, GeoInterfaceRecipes
+using StatsBase: sample
+
+g = graph_from_download(
+    :place_name, 
+    place_name="tiergarten, berlin germany",
+    network_type=:drive
+)
+sg = simplify_graph(g)
+
+# Set plot size
+size = (1920, 1080)
+
+# Show original nodes
+plot(g; size)
+savefig("original_nodes")
+
+# Show relevant nodes
+plot(sg; size)
+savefig("relevant_nodes")
+
+
+
+osm_ids = sample(collect(values(sg.nodes)), 200)
+for source in osm_ids
+    for target in osm_ids
+        path = shortest_path(g, source, target)
+        path_simplified = shortest_path(sg, source, target)
+        if isnothing(path) || isnothing(path_simplified)
+            continue
+        end
+        path_length = total_path_weight(g, path)
+        path_simplified_length = total_path_weight(sg, path_simplified)
+        if !isapprox(path_length, path_simplified_length)
+            error("Path from $source to $target is $path_length in the original graph and $path_simplified_length in the simplified graph")
+        end
+    end
+end

src/LightOSM.jl

@@ -5,7 +5,7 @@ using DataStructures: DefaultDict, OrderedDict, MutableLinkedList
 using QuickHeaps: BinaryHeap, FastMin
 using Statistics: mean
 using SparseArrays: SparseMatrixCSC, sparse, findnz
-using Graphs: AbstractGraph, DiGraph, nv, outneighbors, weakly_connected_components, vertices
+using Graphs: AbstractGraph, DiGraph, nv, outneighbors, weakly_connected_components, vertices, all_neighbors, indegree, outdegree, add_edge!
 using StaticGraphs: StaticDiGraph
 using SimpleWeightedGraphs: SimpleWeightedDiGraph
 using MetaGraphs: MetaDiGraph, set_prop!
@@ -15,9 +15,14 @@ using JSON
 using LightXML
 using StaticArrays
 using SpatialIndexing
+using DataFrames
+using GeoInterface: MultiLineString, LineString, Point 
+using RecipesBase
 
 export GeoLocation,
+       AbstractOSMGraph,
        OSMGraph,
+       SimplifiedOSMGraph,
        Node,
        Way,
        EdgePoint,
@@ -67,7 +72,11 @@ export index_to_node_id,
        set_dijkstra_state_with_index!,
        set_dijkstra_state_with_node_id!,
        maxspeed_from_index,
-       maxspeed_from_node_id
+       maxspeed_from_node_id,
+       simplify_graph,
+       node_gdf,
+       edge_gdf,
+       way_gdf
 
 include("types.jl")
 include("constants.jl")
@@ -83,5 +92,8 @@ include("nearest_node.jl")
 include("nearest_way.jl")
 include("buildings.jl")
 include("subgraph.jl")
+include("simplification.jl")
+include("geodataframes.jl")
+include("plotrecipes.jl")
 
 end # module

src/geodataframes.jl

@@ -0,0 +1,24 @@
+Point(node::Node) = Point(node.location.lon, node.location.lat)
+LineString(g::AbstractOSMGraph, way::Way) = LineString(Point.(g.parent.nodes[i] for i in way.nodes))
+
+function node_gdf(g::AbstractOSMGraph)
+    ids = collect(keys(g.nodes))
+    nodes = (g.nodes[id] for id in ids)
+    return DataFrame(;id=ids, tags=getproperty.(nodes, :tags), geom=Point.(nodes))
+end
+
+function way_gdf(g::AbstractOSMGraph)
+    ids = collect(keys(g.ways))
+    ways = (g.ways[id] for id in ids)
+    return DataFrame(;id=ids, tags=getproperty.(ways, :tags), geom=LineString.(Ref(g), ways))
+end
+
+function edge_gdf(g::SimplifiedOSMGraph)
+    edge_ids = collect(keys(g.edges))
+    geom = map(edge_ids) do edge
+        path = g.edges[edge]
+        LineString(Point.(g.nodes[path]))
+    end
+    u, v, key = map(i -> getindex.(edge_ids, i), 1:3)
+    return DataFrame(;u, v, key, geom=geom)
+end

src/graph_utilities.jl

@@ -1,67 +1,67 @@
 """
-    index_to_node_id(g::OSMGraph, x::DEFAULT_OSM_INDEX_TYPE)
-    index_to_node_id(g::OSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE})
+    index_to_node_id(g::AbstractOSMGraph, x::DEFAULT_OSM_INDEX_TYPE)
+    index_to_node_id(g::AbstractOSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE})
 
 Maps node index to node id.
 """
-index_to_node_id(g::OSMGraph, x::DEFAULT_OSM_INDEX_TYPE) = g.index_to_node[x]
-index_to_node_id(g::OSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE}) = [index_to_node_id(g, i) for i in x]
+index_to_node_id(g::AbstractOSMGraph, x::DEFAULT_OSM_INDEX_TYPE) = g.index_to_node[x]
+index_to_node_id(g::AbstractOSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE}) = [index_to_node_id(g, i) for i in x]
 
 """
-    index_to_node(g::OSMGraph, x::DEFAULT_OSM_INDEX_TYPE)
-    index_to_node(g::OSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE})
+    index_to_node(g::AbstractOSMGraph, x::DEFAULT_OSM_INDEX_TYPE)
+    index_to_node(g::AbstractOSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE})
 
 Maps node index to node object.
 """
-index_to_node(g::OSMGraph, x::DEFAULT_OSM_INDEX_TYPE) = g.nodes[g.index_to_node[x]]
-index_to_node(g::OSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE}) = [index_to_node(g, i) for i in x]
+index_to_node(g::AbstractOSMGraph, x::DEFAULT_OSM_INDEX_TYPE) = g.nodes[g.index_to_node[x]]
+index_to_node(g::AbstractOSMGraph, x::Vector{<:DEFAULT_OSM_INDEX_TYPE}) = [index_to_node(g, i) for i in x]
 
 """
-    node_id_to_index(g::OSMGraph, x::DEFAULT_OSM_ID_TYPE)
-    node_id_to_index(g::OSMGraph, x::Vector{<:DEFAULT_OSM_ID_TYPE})
+    node_id_to_index(g::AbstractOSMGraph, x::DEFAULT_OSM_ID_TYPE)
+    node_id_to_index(g::AbstractOSMGraph, x::Vector{<:DEFAULT_OSM_ID_TYPE})
 
 Maps node id to index.
 """
-node_id_to_index(g::OSMGraph, x::DEFAULT_OSM_ID_TYPE) = g.node_to_index[x]
-node_id_to_index(g::OSMGraph, x::Vector{<:DEFAULT_OSM_ID_TYPE}) = [node_id_to_index(g, i) for i in x]
+node_id_to_index(g::AbstractOSMGraph, x::DEFAULT_OSM_ID_TYPE) = g.node_to_index[x]
+node_id_to_index(g::AbstractOSMGraph, x::Vector{<:DEFAULT_OSM_ID_TYPE}) = [node_id_to_index(g, i) for i in x]
 """
-    node_to_index(g::OSMGraph, x::Node)
-    node_to_index(g::OSMGraph, x::Vector{Node})
+    node_to_index(g::AbstractOSMGraph, x::Node)
+    node_to_index(g::AbstractOSMGraph, x::Vector{Node})
 
 Maps node object to index.
 """
-node_to_index(g::OSMGraph, x::Node) = g.node_to_index[x.id]
-node_to_index(g::OSMGraph, x::Vector{Node}) = [node_id_to_index(g, i.id) for i in x]
+node_to_index(g::AbstractOSMGraph, x::Node) = g.node_to_index[x.id]
+node_to_index(g::AbstractOSMGraph, x::Vector{Node}) = [node_id_to_index(g, i.id) for i in x]
 
 """
-    index_to_dijkstra_state(g::OSMGraph, x::DEFAULT_OSM_INDEX_TYPE)
+    index_to_dijkstra_state(g::AbstractOSMGraph, x::DEFAULT_OSM_INDEX_TYPE)
 
 Maps node index to dijkstra state (parents).
 """
-index_to_dijkstra_state(g::OSMGraph, x::DEFAULT_OSM_INDEX_TYPE) = g.dijkstra_states[x]
+index_to_dijkstra_state(g::AbstractOSMGraph, x::DEFAULT_OSM_INDEX_TYPE) = g.dijkstra_states[x]
 """
-    node_id_to_dijkstra_state(g::OSMGraph, x::DEFAULT_OSM_ID_TYPE)
+    node_id_to_dijkstra_state(g::AbstractOSMGraph, x::DEFAULT_OSM_ID_TYPE)
 
 Maps node id to dijkstra state (parents).
 """
-node_id_to_dijkstra_state(g::OSMGraph, x::DEFAULT_OSM_ID_TYPE) = g.dijkstra_states[node_id_to_index(g, x)]
+node_id_to_dijkstra_state(g::AbstractOSMGraph, x::DEFAULT_OSM_ID_TYPE) = g.dijkstra_states[node_id_to_index(g, x)]
 """
-    set_dijkstra_state_with_index!(g::OSMGraph, index::DEFAULT_OSM_INDEX_TYPE, state)
+    set_dijkstra_state_with_index!(g::AbstractOSMGraph, index::DEFAULT_OSM_INDEX_TYPE, state)
 
 Set dijkstra state (parents) with node index.
 """
-set_dijkstra_state_with_index!(g::OSMGraph, index::DEFAULT_OSM_INDEX_TYPE, state) = push!(g.dijkstra_states, index, state)
+set_dijkstra_state_with_index!(g::AbstractOSMGraph, index::DEFAULT_OSM_INDEX_TYPE, state) = push!(g.dijkstra_states, index, state)
 """
-    set_dijkstra_state_with_node_id!(g::OSMGraph, index::DEFAULT_OSM_ID_TYPE, state)
+    set_dijkstra_state_with_node_id!(g::AbstractOSMGraph, index::DEFAULT_OSM_ID_TYPE, state)
 
 Set dijkstra state (parents) with node id.
 """
-set_dijkstra_state_with_node_id!(g::OSMGraph, node_id::DEFAULT_OSM_ID_TYPE, state) = push!(g.dijkstra_states, node_id_to_index(g, node_id), state)
+set_dijkstra_state_with_node_id!(g::AbstractOSMGraph, node_id::DEFAULT_OSM_ID_TYPE, state) = push!(g.dijkstra_states, node_id_to_index(g, node_id), state)
 """
     maxspeed_from_index(g, x::DEFAULT_OSM_INDEX_TYPE)
     maxspeed_from_node_id(g, x::DEFAULT_OSM_ID_TYPE)
 
 Get maxspeed from index id or node id.
 """
-maxspeed_from_index(g, x::DEFAULT_OSM_INDEX_TYPE) = index_to_node(g, x).tags["maxspeed"]
-maxspeed_from_node_id(g, x::DEFAULT_OSM_ID_TYPE) = g.nodes[x].tags["maxspeed"]
+maxspeed_from_index(g::AbstractOSMGraph, x::DEFAULT_OSM_INDEX_TYPE) = index_to_node(g, x).tags["maxspeed"]
+maxspeed_from_node_id(g::AbstractOSMGraph, x::DEFAULT_OSM_ID_TYPE) = g.nodes[x].tags["maxspeed"]

src/plotrecipes.jl

@@ -0,0 +1,29 @@
+function aspect_ratio(g::AbstractOSMGraph) 
+    max_y, min_y = extrema(first, g.node_coordinates)
+    mid_y = (max_y + min_y)/2
+    return 1/cos(mid_y * pi/180)
+end
+
+RecipesBase.@recipe function f(g::AbstractOSMGraph)
+    # set the aspect ratio
+    aspect_ratio --> aspect_ratio(g)
+
+    # way color and thickness
+    color --> :black
+    linewdith --> 1.5
+    # node color and size
+    markercolor --> :blue
+    markersize --> 2
+
+    # plot ways
+    @series begin
+        seriestype := :path
+        MultiLineString(way_gdf(g).geom)
+    end
+
+    # plot nodes
+    @series begin
+        seriestype := :scatter
+        node_gdf(g).geom
+    end
+end