DXHitTestOptionsOctTreeExpandChildBoundingBoxes Property

ExpandChildBoundingBoxes is a float that defined how much the bounding boxes of node overlap. By default the value is set to 0.2 - so each bounding box is extended for 20% (but it does not go out of the parent's bounding box). This way the triangles that lay on node borders will be put into the child nodes instead of having them in the parent node (there we need to do a hit test every time).

public float OctTreeExpandChildBoundingBoxes { get; set; }