PG/inz-00
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Graph structure for storing Voronoi and Delaunay graphs

Browse Source
This commit is contained in:
Kacper Donat 2019-07-28 15:32:35 +02:00
parent cfc7182eb5
commit 5e8cb736ac
4 changed files with 119 additions and 61 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
Assets/Map/Graph.cs
View File

@ -1,10 +1,21 @@
using System.Collections.Generic;
using System.Linq;
namespace Assets.Map
{
public class Graph<T>
{
public IList<T> Vertices { get; internal set; } = new List<T>();
public List<T> Vertices { get; internal set; } = new List<T>();
public ISet<(int, int)> Edges { get; internal set; } = new HashSet<(int, int)>();
public void AddEdge(int a, int b)
{
Edges.Add(a < b ? (a, b) : (b, a));
}
public IEnumerable<(int, int)> EdgesOf(int a)
{
return Edges.Where(x => x.Item1 == a || x.Item2 == a);
}
}
}

72
Assets/Scripts/GraphGenerator.cs
View File

@ -2,6 +2,7 @@ using System;
using System.Collections.Generic;
using System.Linq;
using Assets.Generators;
using Assets.Map;
using Assets.Voronoi;
using UnityEditor;
using UnityEngine;
@ -18,7 +19,9 @@ namespace Assets
public bool displayParabolas = false;
public bool displayVertices = true;
public bool displayNeighbours = false;
public bool displayLabels= false;
public bool displayLabels = false;
public bool displayHalfEdges = false;
public bool displayEdges = true;
}
[RequireComponent(typeof(MeshRenderer), typeof(MeshFilter)), ExecuteInEditMode]
@ -96,13 +99,10 @@ namespace Assets
if (debug.displayPoints)
{
foreach (var point in _points)
{
Gizmos.color = _colors.ContainsKey(point) ? _colors[point] : Color.white;
Gizmos.DrawSphere(point, 1);
if (debug.displayLabels) Handles.Label(point, $"({point.x:F1}, {point.y:F1})");
}
}
@ -111,26 +111,31 @@ namespace Assets
if (debug.displayNeighbours)
{
Gizmos.color = Color.yellow;
DisplayGraphEdges(generator.Delaunay);
}
foreach (var site in generator.Sites)
if (debug.displayVertices)
{
Gizmos.color = Color.blue;
DisplayGraphVertices(generator.Voronoi);
}
if (debug.displayHalfEdges)
{
Gizmos.color = Color.green;
foreach (var edge in generator.HalfEdges)
{
var vecStart = new Vector3((float)site.Point.x, (float)site.Point.y);
foreach (var neighbour in site.Neighbours)
{
var vecEnd = new Vector3((float)neighbour.Point.x, (float)neighbour.Point.y);
Gizmos.DrawLine(vecStart, vecEnd);
}
var vecStart = new Vector3((float)edge.Start.x, (float)edge.Start.y);
var vecEnd = new Vector3((float)edge.End.x, (float)edge.End.y);
Gizmos.DrawLine(vecStart, vecEnd);
}
}
Gizmos.color = Color.green;
foreach (var edge in generator.Edges)
if (debug.displayEdges)
{
var vecStart = new Vector3((float)edge.start.x, (float)edge.start.y);
var vecEnd = new Vector3((float)edge.end.x, (float)edge.end.y);
Gizmos.DrawLine(vecStart, vecEnd);
Gizmos.color = Color.white;
DisplayGraphEdges(generator.Voronoi);
}
Gizmos.color = Color.red;
@ -153,17 +158,6 @@ namespace Assets
}
}
}
if (debug.displayVertices)
{
foreach (var vertex in generator.Vertices)
{
var point = new Vector3((float)vertex.x, (float)vertex.y);
Gizmos.DrawSphere(point, 1);
if (debug.displayLabels) Handles.Label(point, $"({point.x:F1}, {point.y:F1})");
}
}
if (debug.displayBeachLine)
{
@ -186,5 +180,25 @@ namespace Assets
generator.Step();
}
}
private void DisplayGraphVertices(Graph<Point> graph)
{
var vertices = graph.Vertices.Select(p => new Vector3((float) p.x, (float) p.y));
foreach (var v in vertices)
{
Gizmos.DrawSphere(v, 1);
if (debug.displayLabels) Handles.Label(v, $"({v.x:F2}, {v.y:F2})");
}
}
private void DisplayGraphEdges(Graph<Point> graph)
{
var edges = graph.Edges
.Select(edge => (graph.Vertices[edge.Item1], graph.Vertices[edge.Item2]))
.Select(edge => (new Vector3((float)edge.Item1.x, (float)edge.Item1.y), new Vector3((float)edge.Item2.x, (float)edge.Item2.y)));
foreach (var (s, e) in edges) Gizmos.DrawLine(s, e);
}
}
}

28
Assets/Voronoi/BeachLine.cs
View File

@ -6,10 +6,28 @@ using static System.Math;
namespace Assets.Voronoi
{
public class Edge
public class HalfEdge
{
public Point start = null;
public Point end = null;
public Point Start = null;
public Point End = null;
public int StartVertex = -1;
public int EndVertex = -1;
private HalfEdge _twin;
public HalfEdge Twin
{
get => _twin;
set
{
_twin = value;
value._twin = this;
}
}
public bool IsComplete => (StartVertex != -1 && EndVertex != -1) || (_twin != null && EndVertex != -1 && _twin.EndVertex != -1);
public (int, int) Edge => _twin != null ? (this.EndVertex, _twin.EndVertex) : (StartVertex, EndVertex);
}
public class Parabola
@ -22,8 +40,8 @@ namespace Assets.Voronoi
public Site Site { get; internal set; }
public EdgeEvent Event { get; internal set; }
public Edge LeftEdge { get; set; }
public Edge RightEdge { get; set; }
public HalfEdge LeftEdge { get; set; }
public HalfEdge RightEdge { get; set; }
public override string ToString()
{

67
Assets/Voronoi/VoronoiGenerator.cs
View File

@ -1,5 +1,6 @@
using System.Collections.Generic;
using System.Linq;
using Assets.Map;
using Priority_Queue;
namespace Assets.Voronoi
@ -29,12 +30,13 @@ namespace Assets.Voronoi
public class Site
{
public ISet<Site> Neighbours { get; internal set; } = new HashSet<Site>();
public Point Point { get; internal set; }
public int Index { get; internal set; }
public Site(Point point)
public Site(Point point, int index)
{
Point = point;
Index = index;
}
}
@ -43,8 +45,11 @@ namespace Assets.Voronoi
public IList<Site> Sites { get; }
public IPriorityQueue<IEvent, double> Queue { get; internal set; }
public IList<Point> Vertices { get; internal set; }
public IList<Edge> Edges { get; internal set; }
public Graph<Point> Voronoi;
public Graph<Point> Delaunay;
public List<HalfEdge> HalfEdges;
public BeachLine Line { get; private set; }
@ -52,7 +57,8 @@ namespace Assets.Voronoi
public VoronoiGenerator(IList<Point> sites)
{
Sites = sites.Select(x => new Site(x)).ToList();
int i = 0;
Sites = sites.Select(x => new Site(x, i++)).ToList();
Reset();
}
@ -62,8 +68,11 @@ namespace Assets.Voronoi
Queue = new SimplePriorityQueue<IEvent, double>();
Line = new BeachLine();
Vertices = new List<Point>();
Edges = new List<Edge>();
Voronoi = new Graph<Point>();
Delaunay = new Graph<Point>();
HalfEdges = new List<HalfEdge>();
Delaunay.Vertices.AddRange(from site in Sites select site.Point);
foreach (var site in Sites)
{
@ -110,10 +119,7 @@ namespace Assets.Voronoi
private void HandleEdgeEvent(EdgeEvent @event)
{
var queue = new Queue<RedBlackNode<Parabola>>();
var node = @event.node;
var parabola = node.Value;
var previous = node.Previous;
var next = node.Next;
@ -121,15 +127,30 @@ namespace Assets.Voronoi
if (previous?.Value.Event != null) previous.Value.Event.IsValid = false;
if (next?.Value.Event != null) next.Value.Event.IsValid = false;
Vertices.Add(@event.vertex);
Voronoi.Vertices.Add(@event.vertex);
node.Value.LeftEdge.end = @event.vertex;
node.Value.RightEdge.end = @event.vertex;
node.Value.LeftEdge.End = @event.vertex;
node.Value.LeftEdge.EndVertex = Voronoi.Vertices.Count - 1;
Edges.Add(node.Value.LeftEdge);
Edges.Add(node.Value.RightEdge);
node.Value.RightEdge.End = @event.vertex;
node.Value.RightEdge.EndVertex = Voronoi.Vertices.Count - 1;
var newEdge = new Edge() { start = @event.vertex };
HalfEdges.Add(node.Value.LeftEdge);
HalfEdges.Add(node.Value.RightEdge);
if (node.Value.LeftEdge.IsComplete)
{
var (a, b) = node.Value.LeftEdge.Edge;
Voronoi.AddEdge(a, b);
}
if (node.Value.RightEdge.IsComplete)
{
var (a, b) = node.Value.RightEdge.Edge;
Voronoi.AddEdge(a, b);
}
var newEdge = new HalfEdge() { Start = @event.vertex, StartVertex = Voronoi.Vertices.Count - 1 };
node.Previous.Value.RightEdge = newEdge;
node.Next.Value.LeftEdge = newEdge;
@ -143,10 +164,7 @@ namespace Assets.Voronoi
Enqueue(n);
if (previous != null && next != null)
{
previous.Value.Site.Neighbours.Add(next.Value.Site);
next.Value.Site.Neighbours.Add(previous.Value.Site);
}
Delaunay.AddEdge(next.Value.Site.Index, previous.Value.Site.Index);
}
private void HandleSiteEvent(SiteEvent @event)
@ -163,8 +181,8 @@ namespace Assets.Voronoi
var node = Line.AddParabola(@event.Site, above);
var newLeft = new Edge() { start = start };
var newRight = new Edge() { start = start };
var newLeft = new HalfEdge() { Start = start };
var newRight = new HalfEdge() { Start = start, Twin = newLeft };
node.Previous.Value.LeftEdge = left;
node.Previous.Value.RightEdge = newLeft;
@ -182,10 +200,7 @@ namespace Assets.Voronoi
Enqueue(n);
if (node.Previous != null)
{
@event.Site.Neighbours.Add(node.Previous.Value.Site);
node.Previous.Value.Site.Neighbours.Add(@event.Site);
}
Delaunay.AddEdge(@event.Site.Index, node.Previous.Value.Site.Index);
}
else
{