static protected void TraverseBSPTree(Vector3D origin, BSPTreeNode node, Faces faces)
{
if (node != null)
{
int sign = (int)Math3D.GetSign(node.Plane.GetDistanceToPlane(origin));
if (sign > 0)
{
TraverseBSPTree(origin, node.NegativeChild, faces);
foreach (Face face in node.Faces)
{
if (face.Visible == true)
{
faces.Add(face);
}
}
TraverseBSPTree(origin, node.PositiveChild, faces);
}
else /*if( sign <= 0 )*/
{
TraverseBSPTree(origin, node.PositiveChild, faces);
TraverseBSPTree(origin, node.NegativeChild, faces);
}
}
}
//------------------------------------------------------------------------
static public Faces GetVisibleFaces(Vector3D origin, BSPTreeNode node)
{
Debug.Assert(node != null);
Faces faces = new Faces();
TraverseBSPTree(origin, node, faces);
return(faces);
}
//------------------------------------------------------------------------
static public BSPTreeNode FromFaces(Faces faces)
{
//Debug2.Push();
if (faces.Count == 0)
{
//Debug.WriteLine( "faces == 0" );
//Debug2.Pop();
return(null);
}
/*else if( faces.Count == 1 ) {
* Face face = faces[0];
*
* BSPTreeNode node = new BSPTreeNode();
* node.Plane = face.GetPlane();
* node.Faces.Add( face );
* node.PositiveChild = null;
* node.NegativeChild = null;
*
* return node;
* }
* else {*/
BSPProfiler profilerMinCost = null;
foreach (Face face in faces)
{
BSPProfiler profiler = new BSPProfiler(face.Plane, faces);
if (profilerMinCost == null || profilerMinCost.GetCost() > profiler.GetCost())
{
profilerMinCost = profiler;
}
}
BSPTreeNode node = new BSPTreeNode();
node.Plane = profilerMinCost.Plane;
node.Faces = profilerMinCost.CoplanarFaces;
node.PositiveChild = BSPTreeNode.FromFaces(profilerMinCost.PositiveFaces);
node.NegativeChild = BSPTreeNode.FromFaces(profilerMinCost.NegativeFaces);
return(node);
}