/// <summary>
/// Removes an item from <see cref="QuadTree{T}"/> at a specific location.
/// </summary>
/// <param name="item">Item that has moved.</param>
/// <param name="x">Old X coordinate.</param>
/// <param name="y">Old Y coordinate.</param>
/// <returns>True if successful, false if not.</returns>
protected bool removeAt(T item, float x, float y)
{
if (rootTree.RemoveAt(item, x, y))
{
itemDictionary.Remove(item);
return(true);
}
return(false);
}
/// <summary>
/// Recursively removes an item that changed position.
/// </summary>
/// <param name="item">Item that has changed position</param>
/// <param name="x">Old X coordinate.</param>
/// <param name="y">Old Y coordinate.</param>
/// <returns>Item that was removed.</returns>
public virtual bool RemoveAt(T item, float x, float y)
{
if (!Boundary.ContainsPoint(new XY(x, y)))
{
return(false);
}
if (items.Remove(item))
{
return(true);
}
if (northWest == null)
{
return(false);
}
bool removed = false;
if (northWest.RemoveAt(item, x, y))
{
removed = true;
}
else if (northEast.RemoveAt(item, x, y))
{
removed = true;
}
else if (southWest.RemoveAt(item, x, y))
{
removed = true;
}
else if (southEast.RemoveAt(item, x, y))
{
removed = true;
}
// If a change was made, check if child trees are empty, if so then remove them.
if (removed)
{
clean();
return(true);
}
return(false);
}