public OcttreeNode(ArrayList sceneNodes, int depth, int maxDepth)
{
this.sceneNodes = sceneNodes;
depth++;
if (depth == maxDepth)
{
return;
}
nodeBox = new BoundingBox(-1000000, -1000000, -1000000, 1000000, 1000000, 1000000);
foreach (SceneNode node in sceneNodes)
{
BoundingBox tempBB = node.GetBoundingBox();
if (tempBB.min.x < nodeBox.min.x)
{
nodeBox.min.x = tempBB.min.x;
}
if (tempBB.min.y < nodeBox.min.y)
{
nodeBox.min.y = tempBB.min.y;
}
if (tempBB.min.z < nodeBox.min.z)
{
nodeBox.min.z = tempBB.min.z;
}
if (tempBB.max.x > nodeBox.max.x)
{
nodeBox.max.x = tempBB.max.x;
}
if (tempBB.max.y > nodeBox.max.y)
{
nodeBox.max.y = tempBB.max.y;
}
if (tempBB.max.z > nodeBox.max.z)
{
nodeBox.max.z = tempBB.max.z;
}
}
ArrayList[] childSceneNodes = new ArrayList[8];
for (int i = 0; i < 8; i++)
{
childSceneNodes[i] = new ArrayList();
}
double halfX = ((nodeBox.max.x - nodeBox.min.x) / 2) + nodeBox.min.x;
double halfY = ((nodeBox.max.y - nodeBox.min.y) / 2) + nodeBox.min.y;
double halfZ = ((nodeBox.max.z - nodeBox.min.z) / 2) + nodeBox.min.z;
foreach (SceneNode node in sceneNodes)
{
BoundingBox tempBB = node.GetBoundingBox();
int zMod = 0;
if (tempBB.min.z > halfZ)
{
zMod = 4;
}
if (tempBB.min.x <= halfX && tempBB.min.y <= halfY)
{
childSceneNodes[zMod].Add(node);
}
if (tempBB.min.x > halfX && tempBB.min.y <= halfY)
{
childSceneNodes[zMod + 1].Add(node);
}
if (tempBB.min.x <= halfX && tempBB.min.y > halfY)
{
childSceneNodes[zMod + 2].Add(node);
}
if (tempBB.min.x > halfX && tempBB.min.y > halfY)
{
childSceneNodes[zMod + 3].Add(node);
}
}
for (int i = 0; i < 8; i++)
{
if (childSceneNodes[i].Count > 0)
{
OcttreeNode tempNode = new OcttreeNode(childSceneNodes[i], depth, maxDepth);
childNodes.Add(tempNode);
}
}
}
public void BuildTree(int maxDepth)
{
rootNode = new OcttreeNode(nodes, 0, maxDepth);
boundingBox = rootNode.GetBoundingBox();
}