/// <summary>
/// Allocate links for each of the tile's polygons' vertices
/// </summary>
/// <param name="tile">A tile contains a set of polygons, which are linked to each other</param>
public void ConnectIntLinks(ref MeshTile tile)
{
if (tile == null)
{
return;
}
PolyId polyBase = GetPolyRefBase(tile);
//Iterate through all the polygons
for (int i = 0; i < tile.Header.PolyCount; i++)
{
//The polygon links will end in a null link
tile.Polys[i].FirstLink = Link.Null;
//Avoid Off-Mesh Connection polygons
if (tile.Polys[i].PolyType == PolygonType.OffMeshConnection)
{
continue;
}
//Build edge links
for (int j = tile.Polys[i].VertCount - 1; j >= 0; j--)
{
//Skip hard and non-internal edges
if (tile.Polys[i].Neis[j] == 0 || IsExternalLink(tile.Polys[i].Neis[j]))
{
continue;
}
//Allocate a new link if possible
int idx = AllocLink(tile);
//Allocation of link should be successful
if (IsLinkAllocated(idx))
{
//Initialize a new link
PolyId id;
PolyId.SetPolyIndex(ref polyBase, tile.Polys[i].Neis[j] - 1, out id);
tile.Links[idx].Reference = id;
tile.Links[idx].Edge = j;
tile.Links[idx].Side = BoundarySide.Internal;
tile.Links[idx].BMin = tile.Links[idx].BMax = 0;
//Add to polygon's links list
tile.Links[idx].Next = tile.Polys[i].FirstLink;
tile.Polys[i].FirstLink = idx;
}
}
}
}
/// <summary>
/// Find all the polygons within a certain bounding box.
/// </summary>
/// <param name="tile">Current tile</param>
/// <param name="qbounds">The bounds</param>
/// <param name="polys">List of polygons</param>
/// <returns>Number of polygons found</returns>
public int QueryPolygonsInTile(MeshTile tile, BBox3 qbounds, List <PolyId> polys)
{
if (tile.BVTree.Count != 0)
{
int node = 0;
int end = tile.Header.BvNodeCount;
Vector3 tbmin = tile.Header.Bounds.Min;
Vector3 tbmax = tile.Header.Bounds.Max;
//Clamp query box to world box
Vector3 qbmin = qbounds.Min;
Vector3 qbmax = qbounds.Max;
PolyBounds b;
float bminx = MathHelper.Clamp(qbmin.X, tbmin.X, tbmax.X) - tbmin.X;
float bminy = MathHelper.Clamp(qbmin.Y, tbmin.Y, tbmax.Y) - tbmin.Y;
float bminz = MathHelper.Clamp(qbmin.Z, tbmin.Z, tbmax.Z) - tbmin.Z;
float bmaxx = MathHelper.Clamp(qbmax.X, tbmin.X, tbmax.X) - tbmin.X;
float bmaxy = MathHelper.Clamp(qbmax.Y, tbmin.Y, tbmax.Y) - tbmin.Y;
float bmaxz = MathHelper.Clamp(qbmax.Z, tbmin.Z, tbmax.Z) - tbmin.Z;
const int MinMask = unchecked ((int)0xfffffffe);
b.Min.X = (int)(bminx * tile.Header.BvQuantFactor) & MinMask;
b.Min.Y = (int)(bminy * tile.Header.BvQuantFactor) & MinMask;
b.Min.Z = (int)(bminz * tile.Header.BvQuantFactor) & MinMask;
b.Max.X = (int)(bmaxx * tile.Header.BvQuantFactor + 1) | 1;
b.Max.Y = (int)(bmaxy * tile.Header.BvQuantFactor + 1) | 1;
b.Max.Z = (int)(bmaxz * tile.Header.BvQuantFactor + 1) | 1;
//traverse tree
PolyId polyBase = GetPolyRefBase(tile);
while (node < end)
{
BVTree.Node bvNode = tile.BVTree[node];
bool overlap = PolyBounds.Overlapping(ref b, ref bvNode.Bounds);
bool isLeafNode = bvNode.Index >= 0;
if (isLeafNode && overlap)
{
if (polys.Count < polys.Capacity)
{
PolyId polyRef;
PolyId.SetPolyIndex(ref polyBase, bvNode.Index, out polyRef);
polys.Add(polyRef);
}
}
if (overlap || isLeafNode)
{
node++;
}
else
{
int escapeIndex = -bvNode.Index;
node += escapeIndex;
}
}
return(polys.Count);
}
else
{
BBox3 b;
PolyId polyBase = GetPolyRefBase(tile);
for (int i = 0; i < tile.Header.PolyCount; i++)
{
var poly = tile.Polys[i];
//don't return off-mesh connection polygons
if (poly.PolyType == PolygonType.OffMeshConnection)
{
continue;
}
//calculate polygon bounds
b.Max = b.Min = tile.Verts[poly.Verts[0]];
for (int j = 1; j < poly.VertCount; j++)
{
Vector3 v = tile.Verts[poly.Verts[j]];
Vector3Extensions.ComponentMin(ref b.Min, ref v, out b.Min);
Vector3Extensions.ComponentMax(ref b.Max, ref v, out b.Max);
}
if (BBox3.Overlapping(ref qbounds, ref b))
{
if (polys.Count < polys.Capacity)
{
PolyId polyRef;
PolyId.SetPolyIndex(ref polyBase, i, out polyRef);
polys.Add(polyRef);
}
}
}
return(polys.Count);
}
}
/// <summary>
/// Search for neighbor polygons in the tile.
/// </summary>
/// <param name="va">Vertex A</param>
/// <param name="vb">Vertex B</param>
/// <param name="tile">Current tile</param>
/// <param name="side">Polygon edge</param>
/// <param name="con">Resulting Connection polygon</param>
/// <param name="conarea">Resulting Connection area</param>
public void FindConnectingPolys(Vector3 va, Vector3 vb, MeshTile tile, BoundarySide side, List <PolyId> con, List <float> conarea)
{
if (tile == null)
{
return;
}
Vector2 amin = Vector2.Zero;
Vector2 amax = Vector2.Zero;
CalcSlabEndPoints(va, vb, amin, amax, side);
float apos = GetSlabCoord(va, side);
//Remove links pointing to 'side' and compact the links array
Vector2 bmin = Vector2.Zero;
Vector2 bmax = Vector2.Zero;
PolyId polyBase = GetPolyRefBase(tile);
//Iterate through all the tile's polygons
for (int i = 0; i < tile.Header.PolyCount; i++)
{
int numPolyVerts = tile.Polys[i].VertCount;
//Iterate through all the vertices
for (int j = 0; j < numPolyVerts; j++)
{
//Skip edges which do not point to the right side
if (tile.Polys[i].Neis[j] != (Link.External | (int)side))
{
continue;
}
//Grab two adjacent vertices
Vector3 vc = tile.Verts[tile.Polys[i].Verts[j]];
Vector3 vd = tile.Verts[tile.Polys[i].Verts[(j + 1) % numPolyVerts]];
float bpos = GetSlabCoord(vc, side);
//Segments are not close enough
if (Math.Abs(apos - bpos) > 0.01f)
{
continue;
}
//Check if the segments touch
CalcSlabEndPoints(vc, vd, bmin, bmax, side);
//Skip if slabs don't overlap
if (!OverlapSlabs(amin, amax, bmin, bmax, 0.01f, tile.Header.WalkableClimb))
{
continue;
}
//Add return value
if (con.Count < con.Capacity)
{
conarea.Add(Math.Max(amin.X, bmin.X));
conarea.Add(Math.Min(amax.X, bmax.X));
PolyId id;
PolyId.SetPolyIndex(ref polyBase, i, out id);
con.Add(id);
}
break;
}
}
}
/// <summary>
/// Connect Off-Mesh links between polygons from two different tiles.
/// </summary>
/// <param name="tile">Current Tile</param>
/// <param name="target">Target Tile</param>
/// <param name="side">Polygon edge</param>
public void ConnectExtOffMeshLinks(ref MeshTile tile, ref MeshTile target, BoundarySide side)
{
if (tile == null)
{
return;
}
//Connect off-mesh links, specifically links which land from target tile to this tile
BoundarySide oppositeSide = side.GetOpposite();
//Iterate through all the off-mesh connections of target tile
for (int i = 0; i < target.Header.OffMeshConCount; i++)
{
OffMeshConnection targetCon = target.OffMeshConnections[i];
if (targetCon.Side != oppositeSide)
{
continue;
}
Poly targetPoly = target.Polys[targetCon.Poly];
//Skip off-mesh connections which start location could not be connected at all
if (!IsLinkAllocated(targetPoly.FirstLink))
{
continue;
}
Vector3 extents = new Vector3(targetCon.Radius, target.Header.WalkableClimb, targetCon.Radius);
//Find polygon to connect to
Vector3 p = targetCon.Pos1;
Vector3 nearestPt = new Vector3();
PolyId reference = FindNearestPolyInTile(tile, p, extents, ref nearestPt);
if (reference == PolyId.Null)
{
continue;
}
//Further checks
if ((nearestPt.X - p.X) * (nearestPt.X - p.X) + (nearestPt.Z - p.Z) * (nearestPt.Z - p.Z) >
(targetCon.Radius * targetCon.Radius))
{
continue;
}
//Make sure the location is on the current mesh
target.Verts[targetPoly.Verts[1]] = nearestPt;
//Link off-mesh connection to target poly
int idx = AllocLink(target);
if (IsLinkAllocated(idx))
{
target.Links[idx].Reference = reference;
target.Links[idx].Edge = i;
target.Links[idx].Side = oppositeSide;
target.Links[idx].BMin = target.Links[idx].BMax = 0;
//add to linked list
target.Links[idx].Next = target.Polys[i].FirstLink;
target.Polys[i].FirstLink = idx;
}
//link target poly to off-mesh connection
if ((targetCon.Flags & OffMeshConnectionFlags.Bidirectional) != 0)
{
int tidx = AllocLink(tile);
if (IsLinkAllocated(tidx))
{
int landPolyIdx = reference.DecodePolyIndex(polyBits);
PolyId id;
id = GetPolyRefBase(target);
PolyId.SetPolyIndex(ref id, targetCon.Poly, out id);
tile.Links[tidx].Reference = id;
tile.Links[tidx].Edge = 0xff;
tile.Links[tidx].Side = side;
tile.Links[tidx].BMin = tile.Links[tidx].BMax = 0;
//add to linked list
tile.Links[tidx].Next = tile.Polys[landPolyIdx].FirstLink;
tile.Polys[landPolyIdx].FirstLink = tidx;
}
}
}
}
/// <summary>
/// Begin creating off-mesh links between the tile polygons.
/// </summary>
/// <param name="tile">Current Tile</param>
public void BaseOffMeshLinks(ref MeshTile tile)
{
if (tile == null)
{
return;
}
PolyId polyBase = GetPolyRefBase(tile);
//Base off-mesh connection start points
for (int i = 0; i < tile.Header.OffMeshConCount; i++)
{
int con = i;
int poly = tile.OffMeshConnections[con].Poly;
Vector3 extents = new Vector3(tile.OffMeshConnections[con].Radius, tile.Header.WalkableClimb, tile.OffMeshConnections[con].Radius);
//Find polygon to connect to
Vector3 p = tile.OffMeshConnections[con].Pos0;
Vector3 nearestPt = new Vector3();
PolyId reference = FindNearestPolyInTile(tile, p, extents, ref nearestPt);
if (reference == PolyId.Null)
{
continue;
}
//Do extra checks
if ((nearestPt.X - p.X) * (nearestPt.X - p.X) + (nearestPt.Z - p.Z) * (nearestPt.Z - p.Z) >
tile.OffMeshConnections[con].Radius * tile.OffMeshConnections[con].Radius)
{
continue;
}
//Make sure location is on current mesh
tile.Verts[tile.Polys[poly].Verts[0]] = nearestPt;
//Link off-mesh connection to target poly
int idx = AllocLink(tile);
if (IsLinkAllocated(idx))
{
//Initialize a new link
tile.Links[idx].Reference = reference;
tile.Links[idx].Edge = 0;
tile.Links[idx].Side = BoundarySide.Internal;
tile.Links[idx].BMin = tile.Links[idx].BMax = 0;
//Add to polygon's links list
tile.Links[idx].Next = tile.Polys[poly].FirstLink;
tile.Polys[poly].FirstLink = idx;
}
//Start end-point always conects back to off-mesh connection
int tidx = AllocLink(tile);
if (IsLinkAllocated(tidx))
{
//Initialize a new link
int landPolyIdx = reference.DecodePolyIndex(polyBits);
PolyId id;
PolyId.SetPolyIndex(ref polyBase, tile.OffMeshConnections[con].Poly, out id);
tile.Links[idx].Reference = id;
tile.Links[idx].Edge = 0xff;
tile.Links[idx].Side = BoundarySide.Internal;
tile.Links[idx].BMin = tile.Links[idx].BMax = 0;
//Add to polygon's links list
tile.Links[idx].Next = tile.Polys[landPolyIdx].FirstLink;
tile.Polys[landPolyIdx].FirstLink = tidx;
}
}
}
