/// <summary>
/// Query for the closest Entity to <paramref name="point"/>. (When the Entity was added to this structure.)
///</summary>
/// <remarks>
/// Closeness is based on Euclidean distance. This query only considers
/// points inside the hull around the point, which is described by <paramref name="maxDist"/> (exclusive)
/// and <paramref name="minDist"/> (inclusive).
/// </remarks>
public static Entity QueryClosestPoint(EntityManager mgr, Entity eQuery, float3 point, float maxDist,
float minDist)
{
PointQuerySystemTag tag = mgr.GetComponentData <PointQuerySystemTag>(eQuery);
QueryResult dst;
int n = QueryNearestPoints(tag.queryID, &point, maxDist, minDist, 1, &dst);
return(dst.e);
}
/// <summary>
/// Adds a group of points to the query structure.
/// </summary>
/// <remarks>
/// The id Entity does not have to be a valid entity, and can be treated
/// as an integer id.
/// The only disallowed id is the <see cref="Entity.Null"/>, which is used internally.
/// </remarks>
/// <param name="points">List of points to add. Length must match <paramref name="ids"/>.</param>
/// <param name="ids">List of entities to add. Length must match <paramref name="points"/>.</param>
public static void AddPointsToQueryStruct(EntityManager mgr, Entity eQuery, NativeList <float3> points, NativeList <Entity> ids)
{
if (points.Length != ids.Length)
{
throw new ArgumentException(); // FIXME Does this even work? What should I use?
}
PointQuerySystemTag tag = mgr.GetComponentData <PointQuerySystemTag>(eQuery);
AddPointsToQueryStruct(tag.queryID, points.Length, ids.GetUnsafePtr <Entity>(), points.GetUnsafePtr <float3>());
}
/// <summary>
/// Query for the <paramref name="n"/> closest points to <paramref name="point"/> in in the query structure.
/// </summary>
/// <remarks>
/// Closeness is based on Euclidean distance. This query only considers
/// points inside the hull around the point, which is described by <paramref name="maxDist"/> (exclusive)
/// and <paramref name="minDist"/> (inclusive).
/// Returns a list of ids and distances of the closest points, sorted by
/// most distant first.
/// This is slower than single-point queries. For best results, <paramref name="n"/> should
/// not be too large.
/// </remarks>
public static NativeList <QueryResult> QueryNClosestPoints(EntityManager mgr, Entity eQuery, float3 point, float maxDist, float minDist,
int n)
{
var result = new NativeList <QueryResult>(Allocator.Temp);
result.ResizeUninitialized(n);
PointQuerySystemTag tag = mgr.GetComponentData <PointQuerySystemTag>(eQuery);
int newN = QueryNearestPoints(tag.queryID, &point, maxDist, minDist, n, result.GetUnsafePtr <QueryResult>());
result.ResizeUninitialized(newN);
return(result);
}
/// <summary>
/// Creates a new entity that has a point query structure, and can be passed
/// to other functions in this service.
/// </summary>
/// <remarks>
/// Calls to the PointQueryService are
/// synchronous and immediate; you don't have wait for a System or World update.
///
/// The created entity has an internal hidden component, and an external
/// PointQueryStructTag component.
///
/// To free the allocated memory used by the structure, destroy the entity.
/// </remarks>
public static Entity CreatePointQueryStruct(EntityManager mgr)
{
if (mgr.World.GetExistingSystem(typeof(PointQuerySystem)) == null)
{
mgr.World.AddSystem(new PointQuerySystem());
}
Entity e = mgr.CreateEntity();
int queryID = InitPointQueryStruct(0, 0);
PointQuerySystemTag queryTag = new PointQuerySystemTag()
{
queryID = queryID
};
mgr.AddComponent(e, typeof(PointQuerySystemTag));
mgr.SetComponentData(e, queryTag);
mgr.AddComponent(e, typeof(PointQueryTag));
return(e);
}
/// <summary>
/// Adds a single point to the query structure.
/// </summary>
/// <remarks>
/// The id Entity does not have to be a valid entity, and can be treated
/// as an integer id.
/// The only disallowed id is the <see cref="Entity.Null"/>, which is used internally.
/// </remarks>
public static void AddPointToQueryStruct(EntityManager mgr, Entity eQuery, float3 point, Entity id)
{
PointQuerySystemTag tag = mgr.GetComponentData <PointQuerySystemTag>(eQuery);
AddPointToQueryStruct(tag.queryID, id, &point);
}
/// <summary>
/// Prepares and resets a point query structure.
/// You can use this to clear a query structure, or optimize allocations
/// when the number of items is known ahead of time.
/// </summary>
/// <param name="eQuery">Entity created via createPointQueryStruct</param>
/// <param name="numExpectedPoints">Number of points expected. This is an
/// optional hint for performance and does not need to match exactly. </param>
public static void ResetPointQueryStruct(EntityManager mgr, Entity eQuery, int numExpectedPoints)
{
PointQuerySystemTag tag = mgr.GetComponentData <PointQuerySystemTag>(eQuery);
InitPointQueryStruct(tag.queryID, numExpectedPoints);
}
