public void Initialize(IHeightMapSource heightMap)
{
// Build the quadtree.
var createDescription = new CreateDescription
{
Settings = settings,
HeightMap = heightMap
};
quadTree.Build(ref createDescription);
// Initialize a height map texture.
InitializeHeightMapTexture(heightMap);
}
public Node(int x, int y, int size, ref CreateDescription createDescription)
{
this.x = x;
this.y = y;
this.size = size;
if (size == createDescription.Settings.LeafNodeSize)
{
int limitX = Math.Min(createDescription.HeightMap.Width, x + size + 1);
int limitY = Math.Min(createDescription.HeightMap.Height, y + size + 1);
// this is a leaf node.
createDescription.HeightMap.GetAreaMinMaxHeight(x, y, limitX - x, limitY - y, out minHeight, out maxHeight);
}
else
{
int childSize = size / 2;
childTopLeft = new Node(x, y, childSize, ref createDescription);
minHeight = childTopLeft.minHeight;
maxHeight = childTopLeft.maxHeight;
if (x + childSize < createDescription.HeightMap.Width - 1)
{
childTopRight = new Node(x + childSize, y, childSize, ref createDescription);
minHeight = MathHelper.Min(minHeight, childTopRight.minHeight);
maxHeight = MathHelper.Max(maxHeight, childTopRight.maxHeight);
}
if (y + childSize < createDescription.HeightMap.Height - 1)
{
childBottomLeft = new Node(x, y + childSize, childSize, ref createDescription);
minHeight = MathHelper.Min(minHeight, childBottomLeft.minHeight);
maxHeight = MathHelper.Max(maxHeight, childBottomLeft.maxHeight);
}
if (x + childSize < createDescription.HeightMap.Width - 1 &&
y + childSize < createDescription.HeightMap.Height - 1)
{
childBottomRight = new Node(x + childSize, y + childSize, childSize, ref createDescription);
minHeight = MathHelper.Min(minHeight, childBottomRight.minHeight);
maxHeight = MathHelper.Max(maxHeight, childBottomRight.maxHeight);
}
level = childTopLeft.level + 1;
}
}
public void Build(ref CreateDescription createDescription)
{
var topNodeSize = createDescription.Settings.LeafNodeSize;
for (int i = 1; i < createDescription.Settings.LevelCount; i++)
topNodeSize *= 2;
topNodeCountX = (int) Math.Ceiling((createDescription.HeightMap.Width - 1) / (float) topNodeSize);
topNodeCountY = (int) Math.Ceiling((createDescription.HeightMap.Height - 1) / (float) topNodeSize);
topNodes = new Node[topNodeCountX, topNodeCountY];
for (int y = 0; y < topNodeCountY; y++)
{
for (int x = 0; x < topNodeCountX; x++)
{
topNodes[x, y] = new Node(x * topNodeSize, y * topNodeSize, topNodeSize, ref createDescription);
}
}
}