using FarseerPhysics; using FarseerPhysics.Common; using FarseerPhysics.Dynamics; using FarseerPhysics.Factories; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Graphics; using System; using System.Collections.Generic; using System.Diagnostics; using Voronoi2; namespace Subsurface { class Level { public static Level Loaded { get { return loaded; } } static Level loaded; private int seed; private int siteInterval; const int gridCellWidth = 1000; List[,] cellGrid; //List bodies; List cells; BasicEffect basicEffect; private VertexPositionColor[] vertices; private VertexBuffer vertexBuffer; private Vector2 startPosition; private Vector2 endPosition; Rectangle borders; public Vector2 StartPosition { get { return startPosition; } } public Level(int seed, int width, int height, int siteInterval) { this.seed = seed; this.siteInterval = siteInterval; borders = new Rectangle(0, 0, width, height); } public static Level CreateRandom() { return new Level(100, 100000, 40000, 2000); } public void Generate(float minWidth) { Stopwatch sw = new Stopwatch(); sw.Start(); Game1.random = new Random(seed); if (loaded != this && loaded != null) { loaded.Unload(); } loaded = this; Voronoi voronoi = new Voronoi(1.0); List sites = new List(); Random rand = new Random(seed); float siteVariance = siteInterval * 0.8f; for (int x = siteInterval/2; x < borders.Width; x += siteInterval) { for (int y = siteInterval / 2; y < borders.Height; y += siteInterval) { sites.Add(new Vector2( x + (float)(Game1.random.NextDouble() - 0.5) * siteVariance, y + (float)(Game1.random.NextDouble() - 0.5) * siteVariance)); } } Stopwatch sw2 = new Stopwatch(); sw2.Start(); List graphEdges = voronoi.MakeVoronoiGraph(sites, borders.Width, borders.Height); Debug.WriteLine("MakeVoronoiGraph: " + sw2.ElapsedMilliseconds + " ms"); sw2.Restart(); cellGrid = new List[borders.Width / gridCellWidth, borders.Height / gridCellWidth]; for (int x = 0; x < borders.Width / gridCellWidth; x++) { for (int y = 0; y < borders.Height / gridCellWidth; y++) { cellGrid[x, y] = new List(); } } //construct voronoi cells based on the graph edges cells = new List(); foreach (GraphEdge ge in graphEdges) { for (int i = 0; i < 2; i++) { Site site = (i == 0) ? ge.site1 : ge.site2; VoronoiCell cell = cellGrid[ (int)Math.Floor(site.coord.x / gridCellWidth), (int)Math.Floor(site.coord.y / gridCellWidth)].Find(c => c.site == site); if (cell == null) { cell = new VoronoiCell(site); cellGrid[(int)Math.Floor(cell.Center.X / gridCellWidth), (int)Math.Floor(cell.Center.Y / gridCellWidth)].Add(cell); cells.Add(cell); } if (ge.cell1 == null) { ge.cell1 = cell; } else { ge.cell2 = cell; } cell.edges.Add(ge); } } Debug.WriteLine("find cells: " + sw2.ElapsedMilliseconds + " ms"); sw2.Restart(); //generate a path from the left edge of the map to right edge Rectangle pathBorders = new Rectangle( borders.X + (int)minWidth, borders.Y + (int)minWidth, borders.Right - (int)minWidth, borders.Y + borders.Height - (int)minWidth); List pathCells = GeneratePath( new Vector2((int)minWidth, Game1.random.Next((int)minWidth, borders.Height - (int)minWidth)), new Vector2(borders.Width - (int)minWidth, Game1.random.Next((int)minWidth, borders.Height - (int)minWidth)), cells, pathBorders, minWidth); //generate a couple of random paths for (int i = 0; i < Game1.random.Next() % 3; i++ ) { pathBorders = new Rectangle( borders.X + siteInterval * 2, borders.Y - siteInterval * 2, borders.Right - siteInterval * 2, borders.Y + borders.Height - siteInterval * 2); Vector2 start = pathCells[Game1.random.Next(1,pathCells.Count-2)].Center; Vector2 end = new Vector2(ToolBox.RandomFloat(pathBorders.X, pathBorders.Right), ToolBox.RandomFloat(pathBorders.Y, pathBorders.Bottom)); pathCells.AddRange ( GeneratePath( start,end, cells, pathBorders, 0.0f) ); } Debug.WriteLine("path: " + sw2.ElapsedMilliseconds + " ms"); sw2.Restart(); startPosition = pathCells[0].Center; endPosition = pathCells[pathCells.Count - 1].Center; foreach (VoronoiCell cell in pathCells) { cells.Remove(cell); } GenerateLevel(cells); Debug.WriteLine("Generatelevel: " + sw2.ElapsedMilliseconds + " ms"); sw2.Restart(); vertexBuffer = new VertexBuffer(Game1.CurrGraphicsDevice, VertexPositionColor.VertexDeclaration, vertices.Length, BufferUsage.WriteOnly); vertexBuffer.SetData(vertices); basicEffect = new BasicEffect(Game1.CurrGraphicsDevice); basicEffect.VertexColorEnabled = true; Debug.WriteLine("Generated a map with "+sites.Count+" sites in "+sw.ElapsedMilliseconds+" ms"); } private List GeneratePath(Vector2 start, Vector2 end, List cells, Microsoft.Xna.Framework.Rectangle limits, float minWidth, float wanderAmount = 0.3f) { Stopwatch sw2 = new Stopwatch(); sw2.Start(); //how heavily the path "steers" towards the endpoint //lower values will cause the path to "wander" more, higher will make it head straight to the end wanderAmount = MathHelper.Clamp(wanderAmount, 0.0f, 1.0f); List pathCells = new List(); VoronoiCell currentCell = cells[FindCellIndex(start)]; pathCells.Add(currentCell); VoronoiCell endCell = cells[FindCellIndex(end)]; do { int edgeIndex = 0; //steer towards target if (Game1.random.NextDouble()>wanderAmount) { for (int i = 0; i < currentCell.edges.Count; i++) { if (!IsIntersecting(currentCell.Center, end, currentCell.edges[i].point1, currentCell.edges[i].point2)) continue; edgeIndex = i; break; } } //choose random edge (ignoring ones where the adjacent cell is outside limits) else { List allowedEdges = new List(); foreach(GraphEdge edge in currentCell.edges) { if (!limits.Contains(edge.AdjacentCell(currentCell).Center)) continue; allowedEdges.Add(edge); } edgeIndex = (allowedEdges.Count==0) ? 0 : currentCell.edges.IndexOf(allowedEdges[Game1.random.Next() % allowedEdges.Count]); } currentCell = currentCell.edges[edgeIndex].AdjacentCell(currentCell); pathCells.Add(currentCell); } while (currentCell!=endCell); Debug.WriteLine("genpath: " + sw2.ElapsedMilliseconds + " ms"); sw2.Restart(); List removedCells = GetTooCloseCells(pathCells, minWidth); foreach (VoronoiCell removedCell in removedCells) { if (pathCells.Contains(removedCell)) continue; pathCells.Add(removedCell); } Debug.WriteLine("gettooclose: " + sw2.ElapsedMilliseconds + " ms"); sw2.Restart(); return pathCells; } private List GetTooCloseCells(List emptyCells, float minDistance) { List tooCloseCells = new List(); Vector2 position = emptyCells[0].Center; if (minDistance == 0.0f) return tooCloseCells; float step = 100.0f; int targetCellIndex = 1; minDistance *= 0.5f; do { for (int x = -1; x<=1; x++) { for (int y = -1; y <= 1; y++) { if (x == 0 && y == 0) continue; Vector2 cornerPos = position + new Vector2(x*minDistance, y*minDistance); int cellIndex = FindCellIndex(cornerPos); if (cellIndex == -1) continue; if (!tooCloseCells.Contains(cells[cellIndex])) { tooCloseCells.Add(cells[cellIndex]); } } } position += Vector2.Normalize(emptyCells[targetCellIndex].Center - position) * step; if (Vector2.Distance(emptyCells[targetCellIndex].Center, position) < step * 2.0f) targetCellIndex++; } while (Vector2.Distance(position, emptyCells[emptyCells.Count - 1].Center) > step*2.0f); return tooCloseCells; } ///

/// check whether line from a to b is intersecting with line from c to b ///

bool IsIntersecting(Vector2 a, Vector2 b, Vector2 c, Vector2 d) { float denominator = ((b.X - a.X) * (d.Y - c.Y)) - ((b.Y - a.Y) * (d.X - c.X)); float numerator1 = ((a.Y - c.Y) * (d.X - c.X)) - ((a.X - c.X) * (d.Y - c.Y)); float numerator2 = ((a.Y - c.Y) * (b.X - a.X)) - ((a.X - c.X) * (b.Y - a.Y)); if (denominator == 0) return numerator1 == 0 && numerator2 == 0; float r = numerator1 / denominator; float s = numerator2 / denominator; return (r >= 0 && r <= 1) && (s >= 0 && s <= 1); } ///

/// find the index of the cell which the point is inside /// (actually finds the cell whose center is closest, but it's always the correct cell assuming the point is inside the borders of the diagram) ///

private int FindCellIndex(Vector2 position) { float closestDist = 0.0f; VoronoiCell closestCell = null; int gridPosX = (int)Math.Floor(position.X / gridCellWidth); int gridPosY = (int)Math.Floor(position.Y / gridCellWidth); int searchOffset = 1; for (int x = Math.Max(gridPosX-searchOffset,0); x<=Math.Min(gridPosX+searchOffset, cellGrid.GetLength(0)-1); x++) { for (int y = Math.Max(gridPosY-searchOffset,0); y<=Math.Min(gridPosY+searchOffset, cellGrid.GetLength(1)-1); y++) { for (int i = 0; i < cellGrid[x,y].Count; i++) { float dist = Vector2.Distance(cellGrid[x, y][i].Center, position); if (closestDist != 0.0f && dist > closestDist) continue; closestDist = dist; closestCell = cellGrid[x, y][i]; } } } return cells.IndexOf(closestCell); } private void GenerateLevel(List cells) { List verticeList = new List(); //bodies = new List(); List tempVertices = new List(); int n = 0; foreach (VoronoiCell cell in cells) { n = (n + 30) % 255; tempVertices.Clear(); foreach (GraphEdge ge in cell.edges) { if (ge.point1 == ge.point2) continue; if (!tempVertices.Contains(ge.point1)) tempVertices.Add(ge.point1); if (!tempVertices.Contains(ge.point2)) tempVertices.Add(ge.point2); } if (tempVertices.Count < 3) continue; int triangleCount = tempVertices.Count - 2; tempVertices.Sort(new CompareCCW(cell.Center)); int lastIndex = 1; for (int i = 0; i < triangleCount; i++ ) { List triangleVertices = new List(); triangleVertices.Add(tempVertices[0]); for (int j = lastIndex; j<=lastIndex+1; j++) { triangleVertices.Add(tempVertices[j]); } lastIndex += 1; foreach (Vector2 vertex in triangleVertices) { verticeList.Add(new VertexPositionColor(new Vector3(vertex, 0.0f), Color.LightGray*0.8f));//new Color(n,(n*2)%255,(n*3)%255)*0.5f)); } bool isSame = false; if (triangleVertices[0].Y == triangleVertices[1].Y && triangleVertices[1].Y == triangleVertices[2].Y) isSame = true; if (triangleVertices[0].X == triangleVertices[1].X && triangleVertices[1].X == triangleVertices[2].X) isSame = true; if (isSame) continue; CreateBody(cell, triangleVertices); } } vertices = verticeList.ToArray(); //return bodies; } private void CreateBody(VoronoiCell cell, List bodyVertices) { for (int i = 0; i < bodyVertices.Count; i++) { bodyVertices[i] = ConvertUnits.ToSimUnits(bodyVertices[i]); } //get farseer 'vertices' from vectors Vertices _shapevertices = new Vertices(bodyVertices); //_shapevertices.Sort(new CompareCCW(cell.Center)); //feed vertices array to BodyFactory.CreatePolygon to get a new farseer polygonal body Body _newBody = BodyFactory.CreatePolygon(Game1.world, _shapevertices, 15); _newBody.BodyType = BodyType.Static; _newBody.CollisionCategories = Physics.CollisionWall; cell.bodies.Add(_newBody); } Vector2 position; public void Move(Vector2 amount, float deltaTime) { amount = amount * deltaTime; position += amount; amount = ConvertUnits.ToSimUnits(amount); foreach (VoronoiCell cell in cells) { foreach (Body b in cell.bodies) { b.SetTransform(b.Position+amount, b.Rotation); } } } public void SetObserverPosition(Vector2 position) { position = position - this.position; int gridPosX = (int)Math.Floor(position.X / gridCellWidth); int gridPosY = (int)Math.Floor(position.Y / gridCellWidth); int searchOffset = 1; for (int x = 0; x < cellGrid.GetLength(0); x++) { for (int y = 0; y (PrimitiveType.TriangleList, vertices, 0, (int)Math.Floor(vertices.Length / 3.0f)); } private void Unload() { foreach (VoronoiCell cell in cells) { foreach (Body b in cell.bodies) { Game1.world.RemoveBody(b); } } //bodies = null; vertices = null; cells = null; vertexBuffer.Dispose(); vertexBuffer = null; } } class CompareCCW : IComparer { private Vector2 center; public CompareCCW(Vector2 center) { this.center = center; } public int Compare(Vector2 a, Vector2 b) { if (a.X - center.X >= 0 && b.X - center.X < 0) return -1; if (a.X - center.X < 0 && b.X - center.X >= 0) return 1; if (a.X - center.X == 0 && b.X - center.X == 0) { if (a.Y - center.Y >= 0 || b.Y - center.Y >= 0) return Math.Sign(b.Y-a.Y); return Math.Sign(a.Y-b.Y); } // compute the cross product of vectors (center -> a) x (center -> b) float det = (a.X - center.X) * (b.Y - center.Y) - (b.X - center.X) * (a.Y - center.Y); if (det < 0) return -1; if (det > 0) return 1; // points a and b are on the same line from the center // check which point is closer to the center float d1 = (a.X - center.X) * (a.X - center.X) + (a.Y - center.Y) * (a.Y - center.Y); float d2 = (b.X - center.X) * (b.X - center.X) + (b.Y - center.Y) * (b.Y - center.Y); return Math.Sign(d2-d1); } } }