/** Checks the given OctreeNode, and determines if it needs to be moved
* to a different octant.
*/
public void UpdateOctreeNode(OctreeNode node) {
AxisAlignedBox box = node.WorldAABB;
if(box.IsNull) {
return;
}
if(node.Octant == null) {
//if outside the octree, force into the root node.
if(!node.IsInBox(octree.Box)) {
octree.AddNode(node);
}
else {
AddOctreeNode(node, octree);
return;
}
}
if(!node.IsInBox(node.Octant.Box)) {
RemoveOctreeNode(node);
//if outside the octree, force into the root node.
if(!node.IsInBox(octree.Box)) {
octree.AddNode(node);
}
else {
AddOctreeNode(node,octree);
}
}
}
public void AddOctreeNode(OctreeNode node, Octree octant, int depth) {
AxisAlignedBox box = node.WorldAABB;
//if the octree is twice as big as the scene node,
//we will add it to a child.
if((depth < maxDepth) && octant.IsTwiceSize(box)) {
int x,y,z;
octant.GetChildIndexes(box, out x, out y, out z);
if(octant.Children[x,y,z] == null) {
octant.Children[x,y,z] = new Octree(octant);
Vector3[] corners = octant.Box.Corners;
Vector3 min, max;
if(x == 0) {
min.x = corners[0].x;
max.x = (corners[0].x + corners[4].x) / 2;
}
else {
min.x = (corners[0].x + corners[4].x) / 2;
max.x = corners[4].x;
}
if ( y == 0 ) {
min.y = corners[ 0 ].y;
max.y = ( corners[ 0 ].y + corners[ 4 ].y ) / 2;
}
else {
min.y = ( corners[ 0 ].y + corners[ 4 ].y ) / 2;
max.y = corners[ 4 ].y;
}
if ( z == 0 ) {
min.z = corners[ 0 ].z;
max.z = ( corners[ 0 ].z + corners[ 4 ].z ) / 2;
}
else {
min.z = ( corners[ 0 ].z + corners[ 4 ].z ) / 2;
max.z = corners[ 4 ].z;
}
octant.Children[x,y,z].Box.SetExtents(min,max);
octant.Children[x,y,z].HalfSize = (max - min) / 2;
}
AddOctreeNode(node, octant.Children[x,y,z], ++depth);
}
else {
octant.AddNode(node);
}
}
public void AddOctreeNode( OctreeNode node, Octree octant, int depth )
{
AxisAlignedBox box = node.WorldAABB;
//if the octree is twice as big as the scene node,
//we will add it to a child.
if ( ( depth < maxDepth ) && octant.IsTwiceSize( box ) )
{
int x, y, z;
octant.GetChildIndexes( box, out x, out y, out z );
if ( octant.Children[ x, y, z ] == null )
{
octant.Children[ x, y, z ] = new Octree( octant );
Vector3[] corners = octant.Box.Corners;
Vector3 min, max;
if ( x == 0 )
{
min.x = corners[ 0 ].x;
max.x = ( corners[ 0 ].x + corners[ 4 ].x ) / 2;
}
else
{
min.x = ( corners[ 0 ].x + corners[ 4 ].x ) / 2;
max.x = corners[ 4 ].x;
}
if ( y == 0 )
{
min.y = corners[ 0 ].y;
max.y = ( corners[ 0 ].y + corners[ 4 ].y ) / 2;
}
else
{
min.y = ( corners[ 0 ].y + corners[ 4 ].y ) / 2;
max.y = corners[ 4 ].y;
}
if ( z == 0 )
{
min.z = corners[ 0 ].z;
max.z = ( corners[ 0 ].z + corners[ 4 ].z ) / 2;
}
else
{
min.z = ( corners[ 0 ].z + corners[ 4 ].z ) / 2;
max.z = corners[ 4 ].z;
}
octant.Children[ x, y, z ].Box.SetExtents( min, max );
octant.Children[ x, y, z ].HalfSize = ( max - min ) / 2;
}
AddOctreeNode( node, octant.Children[ x, y, z ], ++depth );
}
else
{
octant.AddNode( node );
}
}