/// <summary>
/// Generates triangles for an infinite plane that will completely intersect the given bounding box
/// </summary>
private NavigationMeshInputBuilder BuildPlaneGeometry(Plane plane, BoundingBox boundingBox)
{
Vector3 maxSize = boundingBox.Maximum - boundingBox.Minimum;
float maxDiagonal = Math.Max(maxSize.X, Math.Max(maxSize.Y, maxSize.Z));
// Generate source plane triangles
Vector3[] planePoints;
int[] planeInds;
NavigationMeshBuildUtils.BuildPlanePoints(ref plane, maxDiagonal, out planePoints, out planeInds);
Vector3 tangent, bitangent;
NavigationMeshBuildUtils.GenerateTangentBinormal(plane.Normal, out tangent, out bitangent);
// Calculate plane offset so that the plane always covers the whole range of the bounding box
Vector3 planeOffset = Vector3.Dot(boundingBox.Center, tangent) * tangent;
planeOffset += Vector3.Dot(boundingBox.Center, bitangent) * bitangent;
VertexPositionNormalTexture[] vertices = new VertexPositionNormalTexture[planePoints.Length];
for (int i = 0; i < planePoints.Length; i++)
{
vertices[i] = new VertexPositionNormalTexture(planePoints[i] + planeOffset, Vector3.UnitY, Vector2.Zero);
}
GeometricMeshData <VertexPositionNormalTexture> meshData = new GeometricMeshData <VertexPositionNormalTexture>(vertices, planeInds, true);
NavigationMeshInputBuilder inputBuilder = new NavigationMeshInputBuilder();
inputBuilder.AppendMeshData(meshData, Matrix.Identity);
return(inputBuilder);
}
/// <summary>
/// Rebuilds outdated triangle data for colliders and recalculates hashes storing everything in StaticColliderData
/// </summary>
private void BuildInput(StaticColliderData[] collidersLocal, CollisionFilterGroupFlags includedCollisionGroups)
{
NavigationMeshCache lastCache = oldNavigationMesh?.Cache;
bool clearCache = false;
Dispatcher.ForEach(collidersLocal, colliderData =>
{
var entity = colliderData.Component.Entity;
TransformComponent entityTransform = entity.Transform;
Matrix entityWorldMatrix = entityTransform.WorldMatrix;
NavigationMeshInputBuilder entityNavigationMeshInputBuilder = colliderData.InputBuilder = new NavigationMeshInputBuilder();
// Compute hash of collider and compare it with the previous build if there is one
colliderData.ParameterHash = NavigationMeshBuildUtils.HashEntityCollider(colliderData.Component, includedCollisionGroups);
colliderData.Previous = null;
if (lastCache?.Objects.TryGetValue(colliderData.Component.Id, out colliderData.Previous) ?? false)
{
if (colliderData.Previous.ParameterHash == colliderData.ParameterHash)
{
// In this case, we don't need to recalculate the geometry for this shape, since it wasn't changed
// here we take the triangle mesh from the previous build as the current
colliderData.InputBuilder = colliderData.Previous.InputBuilder;
colliderData.Planes.Clear();
colliderData.Planes.AddRange(colliderData.Previous.Planes);
colliderData.Processed = false;
return;
}
}
// Clear cache on removal of infinite planes
if (colliderData.Planes.Count > 0)
{
clearCache = true;
}
// Clear planes
colliderData.Planes.Clear();
// Return empty data for disabled colliders, filtered out colliders or trigger colliders
if (!colliderData.Component.Enabled || colliderData.Component.IsTrigger ||
!NavigationMeshBuildUtils.CheckColliderFilter(colliderData.Component, includedCollisionGroups))
{
colliderData.Processed = true;
return;
}
// Make sure shape is up to date
colliderData.Component.ComposeShape();
// Interate through all the colliders shapes while queueing all shapes in compound shapes to process those as well
Queue <ColliderShape> shapesToProcess = new Queue <ColliderShape>();
if (colliderData.Component.ColliderShape != null)
{
shapesToProcess.Enqueue(colliderData.Component.ColliderShape);
while (shapesToProcess.Count > 0)
{
var shape = shapesToProcess.Dequeue();
var shapeType = shape.GetType();
if (shapeType == typeof(BoxColliderShape))
{
var box = (BoxColliderShape)shape;
var boxDesc = GetColliderShapeDesc <BoxColliderShapeDesc>(box.Description);
Matrix transform = box.PositiveCenterMatrix * entityWorldMatrix;
var meshData = GeometricPrimitive.Cube.New(boxDesc.Size, toLeftHanded: true);
entityNavigationMeshInputBuilder.AppendMeshData(meshData, transform);
}
else if (shapeType == typeof(SphereColliderShape))
{
var sphere = (SphereColliderShape)shape;
var sphereDesc = GetColliderShapeDesc <SphereColliderShapeDesc>(sphere.Description);
Matrix transform = sphere.PositiveCenterMatrix * entityWorldMatrix;
var meshData = GeometricPrimitive.Sphere.New(sphereDesc.Radius, toLeftHanded: true);
entityNavigationMeshInputBuilder.AppendMeshData(meshData, transform);
}
else if (shapeType == typeof(CylinderColliderShape))
{
var cylinder = (CylinderColliderShape)shape;
var cylinderDesc = GetColliderShapeDesc <CylinderColliderShapeDesc>(cylinder.Description);
Matrix transform = cylinder.PositiveCenterMatrix * entityWorldMatrix;
var meshData = GeometricPrimitive.Cylinder.New(cylinderDesc.Height, cylinderDesc.Radius, toLeftHanded: true);
entityNavigationMeshInputBuilder.AppendMeshData(meshData, transform);
}
else if (shapeType == typeof(CapsuleColliderShape))
{
var capsule = (CapsuleColliderShape)shape;
var capsuleDesc = GetColliderShapeDesc <CapsuleColliderShapeDesc>(capsule.Description);
Matrix transform = capsule.PositiveCenterMatrix * entityWorldMatrix;
var meshData = GeometricPrimitive.Capsule.New(capsuleDesc.Length, capsuleDesc.Radius, toLeftHanded: true);
entityNavigationMeshInputBuilder.AppendMeshData(meshData, transform);
}
else if (shapeType == typeof(ConeColliderShape))
{
var cone = (ConeColliderShape)shape;
var coneDesc = GetColliderShapeDesc <ConeColliderShapeDesc>(cone.Description);
Matrix transform = cone.PositiveCenterMatrix * entityWorldMatrix;
var meshData = GeometricPrimitive.Cone.New(coneDesc.Radius, coneDesc.Height, toLeftHanded: true);
entityNavigationMeshInputBuilder.AppendMeshData(meshData, transform);
}
else if (shapeType == typeof(StaticPlaneColliderShape))
{
var planeShape = (StaticPlaneColliderShape)shape;
var planeDesc = GetColliderShapeDesc <StaticPlaneColliderShapeDesc>(planeShape.Description);
Matrix transform = entityWorldMatrix;
Plane plane = new Plane(planeDesc.Normal, planeDesc.Offset);
// Pre-Transform plane parameters
plane.Normal = Vector3.TransformNormal(planeDesc.Normal, transform);
plane.Normal.Normalize();
plane.D += Vector3.Dot(transform.TranslationVector, plane.Normal);
colliderData.Planes.Add(plane);
}
else if (shapeType == typeof(ConvexHullColliderShape))
{
var hull = (ConvexHullColliderShape)shape;
Matrix transform = hull.PositiveCenterMatrix * entityWorldMatrix;
// Convert hull indices to int
int[] indices = new int[hull.Indices.Count];
if (hull.Indices.Count % 3 != 0)
{
throw new InvalidOperationException("Physics hull does not consist of triangles");
}
for (int i = 0; i < hull.Indices.Count; i += 3)
{
indices[i] = (int)hull.Indices[i];
indices[i + 2] = (int)hull.Indices[i + 1]; // NOTE: Reversed winding to create left handed input
indices[i + 1] = (int)hull.Indices[i + 2];
}
entityNavigationMeshInputBuilder.AppendArrays(hull.Points.ToArray(), indices, transform);
}
else if (shapeType == typeof(CompoundColliderShape))
{
// Unroll compound collider shapes
var compound = (CompoundColliderShape)shape;
for (int i = 0; i < compound.Count; i++)
{
shapesToProcess.Enqueue(compound[i]);
}
}
}
}
// Clear cache on addition of infinite planes
if (colliderData.Planes.Count > 0)
{
clearCache = true;
}
// Mark collider as processed
colliderData.Processed = true;
});
if (clearCache && oldNavigationMesh != null)
{
oldNavigationMesh = null;
}
}