v5.0
Returns a PointLocatorData
containing closest surface locations from the input position within
a search sphere of a specific radius. By default, the input
positions have to be defined in the object's local space reference.
Optionally, the search can be restricted to return a maximum number
of locations. In order to avoid volumetric restrictions, simply
specify a very large radius.
Some aspects of the closest locations's computation such as the
reference pose or the method (closest surface, closest vertex or
knot, ...) can be set up using Geometry.SetupPointLocatorQueries.
This setup will affect all subsequent calls to
GetClosestLocationsWithinRadius and to Geometry.GetClosestLocations.
If the search was set up with Geometry.SetupPointLocatorQueries
to be a closest surface or smoothed closest surface search, then it
returns one point locator per connected island for PolygonMeshes. Such connected islands are
defined so that you cannot walk between 2 returned point locators
without leaving the search radius (this walking is through polygon
adjacency, not vertex adjacency). For NurbsSurfaceMeshes, it returns at most
one point locator.
When you call this method an acceleration cache is automatically
created. See Geometry.SetupPointLocatorQueries
for more information.
Notice that the "closest distance" relationship may change relative
to the spatial reference of the geometry and the input positions.
See Geometry.SetupPointLocatorQueries
for more information.
Notice that the returned point locators can be evaluated on any
Geometry instance having the same topology.
oReturn = Geometry.GetClosestLocationsWithinRadius( Position, Radius, [MaxNbToFind] ); |
| Parameter | Type | Description |
|---|---|---|
| Position | 1D Array or SIVector3 | The position to search from, either a vector or an XYZ array. |
| Radius | Double | Radius defining a spherical restriction volume for the search. |
| MaxNbToFind | Long | Maximum point locations to find (no limit if value is -1).
Default Value: -1 |
'
' This example uses PointLocatorData to find closest vertices on a polygon mesh
' within a specific radius, and then creates a cluster on these points.
'
NewScene , false
set root = Application.ActiveSceneRoot
set GridObj = root.AddGeometry("Grid", "MeshSurface")
set GridGeom = GridObj.ActivePrimitive.Geometry
Translate GridObj, 0, 0, -2.0, siRelative, siView, siObj, siXYZ
' Set up to closest vertex search
GridGeom.SetupPointLocatorQueries siClosestVertexOrKnot, GridObj.Kinematics.Global.Transform, null, -1
' Get all vertices within a radius of 2 units relatively to the world center
set PositionToQuery = XSIMath.CreateVector3()
PositionToQuery.Set 0,0,0
set PointLocatorsWithinTwoUnits = GridGeom.GetClosestLocationsWithinRadius(PositionToQuery, 2.0)
VerticesString = " "
Dim PtLocIndexToQuery(0)
Dim ClosestVerticesArray()
ReDim ClosestVerticesArray(PointLocatorsWithinTwoUnits.Count-1)
for i = 0 to PointLocatorsWithinTwoUnits.Count-1
' Even though the point locators have be defined to exactly match the vertex
' positions, the search data is returned as a position on a specific triangle,
' just as any other use of the Point Locator. However the vertex that matches
' can be determined because it will be weighted at 100%.
PtLocIndexToQuery(0) = i
SubTriangleVertices = GridGeom.GetTriangleVertexIndexArray(PointLocatorsWithinTwoUnits, PtLocIndexToQuery)
SubTriangleWeights = GridGeom.GetTriangleWeightArray(PointLocatorsWithinTwoUnits, PtLocIndexToQuery)
for ctr = 0 to UBound(SubTriangleVertices,2)
VtxIdx = SubTriangleVertices(0,ctr)
if SubTriangleWeights(1,ctr) > SubTriangleWeights(0,ctr) & SubTriangleWeights(1,ctr) > SubTriangleWeights(2,ctr) then
VtxIdx = SubTriangleVertices(1,ctr)
elseif SubTriangleWeights(2,ctr) > SubTriangleWeights(0,ctr) & SubTriangleWeights(2,ctr) > SubTriangleWeights(1,ctr) then
VtxIdx = SubTriangleVertices(2,ctr)
end if
ClosestVerticesArray(i) = VtxIdx
VerticesString = VerticesString & VtxIdx
if i <> PointLocatorsWithinTwoUnits.Count - 1 then
VerticesString = VerticesString & ", "
end if
next
next
' Create a cluster on these vertices
GridGeom.AddCluster siVertexCluster, "ClosestVertices", ClosestVerticesArray
Application.LogMessage "There are " & PointLocatorsWithinTwoUnits.Count & " grid vertices in the 2 unit sphere located at the world center."
Application.LogMessage "These vertices are (ordered by proximity):"
Application.LogMessage VerticesString
' Expected results:
'INFO : There are 13 grid vertices in the 2 unit sphere located at the world center.
'INFO : These vertices are (ordered by proximity):
'INFO : 42, 51, 41, 33, 43, 52, 32, 50, 34, 24, 60, 40, 44
|
PointLocatorData Geometry Geometry.GetClosestLocations Geometry.GetRaycastIntersections Geometry.SetupPointLocatorQueries Geometry.GetSurfacePointLocatorsFromPoints Geometry.EvaluatePositions Geometry.EvaluateNormals Geometry.EvaluateClusterProperty PolygonMesh.GetPolygonIndexArray PolygonMesh.GetTriangleVertexIndexArray PolygonMesh.GetTriangleNodeIndexArray PolygonMesh.GetTriangleWeightArray PolygonMesh.ConstructPointLocators NurbsSurfaceMesh.GetSubSurfaceIndexArray NurbsSurfaceMesh.GetNormalizedUVArray NurbsSurfaceMesh.ConstructPointLocators