private bool IsInsideMesh(Vector3 p, SpatialBinaryTree tree, Dictionary <Vector3, bool> pointInsideMeshCache)
{
bool isInsideMesh;
if (pointInsideMeshCache.TryGetValue(Vector3.one, out isInsideMesh))
{
return(isInsideMesh);
}
var r = new Ray(p, new Vector3(1, 0, 0));
var intersectionCount = tree.GetTris(r).Count(t => t.Intersect(r));
var isInside = intersectionCount % 2 != 0;
pointInsideMeshCache[p] = isInside;
return(isInside);
}
private IEnumerable <Box> CreateMeshIntersectingBoxes(GameObject colliderGo)
{
var go = colliderGo.transform.parent.gameObject;
var colliderLayer = colliderGo.layer;
LayerMask colliderLayerMask = 1 << colliderLayer;
var bounds = CalculateLocalBounds(go);
var mesh = colliderGo.GetComponent <MeshFilter>().sharedMesh;
var swTree = Stopwatch.StartNew();
var tree = new SpatialBinaryTree(mesh, spatialTreeLevelDepth);
swTree.Stop();
if (outputTimeMeasurements)
{
Debug.Log("SpatialTree Built in " + swTree.Elapsed);
}
var boxes = new Box[boxesPerEdge, boxesPerEdge, boxesPerEdge];
var boxColliderPositions = new bool[boxesPerEdge, boxesPerEdge, boxesPerEdge];
var s = bounds.size / boxesPerEdge;
var halfExtent = s / 2f;
var directionsFromBoxCenterToCorners = new[]
{
new Vector3(1, 1, 1),
new Vector3(1, 1, -1),
new Vector3(1, -1, 1),
new Vector3(1, -1, -1),
new Vector3(-1, 1, 1),
new Vector3(-1, 1, -1),
new Vector3(-1, -1, 1),
new Vector3(-1, -1, -1),
};
var pointInsideMeshCache = new Dictionary <Vector3, bool>();
var sw = Stopwatch.StartNew();
var colliders = new Collider[1000];
for (var x = 0; x < boxesPerEdge; x++)
{
for (var y = 0; y < boxesPerEdge; y++)
{
for (var z = 0; z < boxesPerEdge; z++)
{
var center = new Vector3(
bounds.center.x - bounds.size.x / 2 + s.x * x + halfExtent.x,
bounds.center.y - bounds.size.y / 2 + s.y * y + halfExtent.y,
bounds.center.z - bounds.size.z / 2 + s.z * z + halfExtent.z);
if (!avoidExceedingMesh)
{
if (avoidGapsInside)
{
var isInsideSurface = IsInsideMesh(center, tree, pointInsideMeshCache);
boxColliderPositions[x, y, z] = isInsideSurface;
}
else
{
var overlapsWithMeshSurface = Physics.OverlapBoxNonAlloc(center, halfExtent, colliders, Quaternion.identity, colliderLayerMask) > 0;
boxColliderPositions[x, y, z] = overlapsWithMeshSurface;
}
continue;
}
var allCornersInsideMesh =
(from d in directionsFromBoxCenterToCorners
select new Vector3(center.x + halfExtent.x * d.x, center.y + halfExtent.y * d.y, center.z + halfExtent.z * d.z))
.All(cornerPoint => IsInsideMesh(cornerPoint, tree, pointInsideMeshCache));
boxColliderPositions[x, y, z] = allCornersInsideMesh;
}
}
}
sw.Stop();
if (outputTimeMeasurements)
{
Debug.Log("Boxes analyzed in " + sw.Elapsed);
}
for (var x = 0; x < boxesPerEdge; x++)
{
for (var y = 0; y < boxesPerEdge; y++)
{
for (var z = 0; z < boxesPerEdge; z++)
{
if (!boxColliderPositions[x, y, z])
{
continue;
}
var center = new Vector3(
bounds.center.x - bounds.size.x / 2 + s.x * x + s.x / 2,
bounds.center.y - bounds.size.y / 2 + s.y * y + s.y / 2,
bounds.center.z - bounds.size.z / 2 + s.z * z + s.z / 2);
var b = new Box(boxes, center, s, new Vector3Int(x, y, z));
boxes[x, y, z] = b;
yield return(b);
}
}
}
}
