示例#1
0
        protected void InvalidateNeighbors(AvlNode <MutablePoint> pointPrevious, AvlNode <MutablePoint> pointNew, AvlNode <MutablePoint> pointNext)
        {
            bool invalidPoint;

            if (pointPrevious != null)
            {
                AvlNode <MutablePoint> previousPrevious = pointPrevious.GetPreviousNode();
                for (; ;)
                {
                    if (previousPrevious == null)
                    {
                        break;
                    }

                    invalidPoint = !this.IsPointToTheRightOfOthers(previousPrevious.Item, pointNew.Item, pointPrevious.Item);
                    if (!invalidPoint)
                    {
                        break;
                    }

                    MutablePoint pointPrevPrev = previousPrevious.Item;
                    this.RemoveNode(pointPrevious);
                    pointPrevious    = this.GetNode(pointPrevPrev);
                    previousPrevious = pointPrevious.GetPreviousNode();
                }
            }

            // Invalidate next(s)
            if (pointNext != null)
            {
                AvlNode <MutablePoint> nextNext = pointNext.GetNextNode();
                for (; ;)
                {
                    if (nextNext == null)
                    {
                        break;
                    }

                    invalidPoint = !this.IsPointToTheRightOfOthers(pointNew.Item, nextNext.Item, pointNext.Item);
                    if (!invalidPoint)
                    {
                        break;
                    }

                    MutablePoint pointNextNext = nextNext.Item;
                    this.RemoveNode(pointNext);
                    pointNext = this.GetNode(pointNextNext);
                    nextNext  = pointNext.GetNextNode();
                }
            }
        }
        /// <summary>
        /// Iterate over each points to see if we can add it has a ConvexHull point.
        /// It is specific by Quadrant to improve efficiency.
        /// </summary>
        /// <param name="point">a point</param>
        //// [MethodImpl(MethodImplOptions.AggressiveInlining)]
        internal override void ProcessPoint(ref MutablePoint point)
        {
            this.CurrentNode = this.Root;
            AvlNode <MutablePoint> currentPrevious = null;
            AvlNode <MutablePoint> currentNext     = null;

            while (this.CurrentNode != null)
            {
                var insertionSide = Side.Unknown;
                if (point.X > this.CurrentNode.Item.X)
                {
                    if (this.CurrentNode.Left != null)
                    {
                        this.CurrentNode = this.CurrentNode.Left;
                        continue;
                    }

                    currentPrevious = this.CurrentNode.GetPreviousNode();
                    if (CanQuickReject(ref point, ref currentPrevious.Item))
                    {
                        return;
                    }

                    if (!this.IsPointToTheRightOfOthers(currentPrevious.Item, this.CurrentNode.Item, point))
                    {
                        return;
                    }

                    // Ensure to have no duplicate
                    if (this.CurrentNode.Item == point)
                    {
                        return;
                    }

                    insertionSide = Side.Left;
                }
                else if (point.X < this.CurrentNode.Item.X)
                {
                    if (this.CurrentNode.Right != null)
                    {
                        this.CurrentNode = this.CurrentNode.Right;
                        continue;
                    }

                    currentNext = this.CurrentNode.GetNextNode();
                    if (CanQuickReject(ref point, ref currentNext.Item))
                    {
                        return;
                    }

                    if (!this.IsPointToTheRightOfOthers(this.CurrentNode.Item, currentNext.Item, point))
                    {
                        return;
                    }

                    // Ensure to have no duplicate
                    if (this.CurrentNode.Item == point)
                    {
                        continue;
                    }

                    insertionSide = Side.Right;
                }
                else
                {
                    if (point.Y <= this.CurrentNode.Item.Y)
                    {
                        return; // invalid point
                    }

                    // Replace CurrentNode point with point
                    this.CurrentNode.Item = point;
                    this.InvalidateNeighbors(this.CurrentNode.GetPreviousNode(), this.CurrentNode, this.CurrentNode.GetNextNode());
                    return;
                }

                // We should insert the point
                // Try to optimize and verify if can replace a node instead insertion to minimize tree balancing
                if (insertionSide == Side.Right)
                {
                    currentPrevious = this.CurrentNode.GetPreviousNode();
                    if (currentPrevious != null && !this.IsPointToTheRightOfOthers(currentPrevious.Item, point, this.CurrentNode.Item))
                    {
                        this.CurrentNode.Item = point;
                        this.InvalidateNeighbors(currentPrevious, this.CurrentNode, currentNext);
                        return;
                    }

                    var nextNext = currentNext.GetNextNode();
                    if (nextNext != null && !this.IsPointToTheRightOfOthers(point, nextNext.Item, currentNext.Item))
                    {
                        currentNext.Item = point;
                        this.InvalidateNeighbors(null, currentNext, nextNext);
                        return;
                    }
                }
                else
                {
                    // Left
                    currentNext = this.CurrentNode.GetNextNode();
                    if (currentNext != null && !this.IsPointToTheRightOfOthers(point, currentNext.Item, this.CurrentNode.Item))
                    {
                        this.CurrentNode.Item = point;
                        this.InvalidateNeighbors(currentPrevious, this.CurrentNode, currentNext);
                        return;
                    }

                    var previousPrevious = currentPrevious.GetPreviousNode();
                    if (previousPrevious != null && !this.IsPointToTheRightOfOthers(previousPrevious.Item, point, currentPrevious.Item))
                    {
                        currentPrevious.Item = point;
                        this.InvalidateNeighbors(previousPrevious, currentPrevious, null);
                        return;
                    }
                }

                // Should insert but no invalidation is required. (That's why we need to insert... can't replace an adjacent neighbor)
                AvlNode <MutablePoint> newNode = new AvlNode <MutablePoint>();
                if (insertionSide == Side.Right)
                {
                    newNode.Parent         = this.CurrentNode;
                    newNode.Item           = point;
                    this.CurrentNode.Right = newNode;
                    this.AddBalance(newNode.Parent, -1);
                }
                else
                {
                    // Left
                    newNode.Parent        = this.CurrentNode;
                    newNode.Item          = point;
                    this.CurrentNode.Left = newNode;
                    this.AddBalance(newNode.Parent, 1);
                }

                return;
            }
        }
示例#3
0
        /// <summary>
        /// Copies to an array
        /// </summary>
        /// <param name="array">The array to copy to</param>
        /// <param name="index">start point</param>
        /// <param name="count">number of items to copy</param>
        public void CopyTo(T[] array, int index, int count)
        {
            if (array == null)
            {
                throw new ArgumentNullException("'array' can't be null");
            }

            if (index < 0)
            {
                throw new ArgumentException("'index' can't be null");
            }

            if (count < 0)
            {
                throw new ArgumentOutOfRangeException("'count' should be greater or equal to 0");
            }

            if (index > array.Length || count > array.Length - index)
            {
                throw new ArgumentException("The array size is not big enough to get all items");
            }

            if (count == 0)
            {
                return;
            }

            int indexIter  = 0;
            int indexArray = 0;

            AvlNode <T> current = this.GetFirstNode();

            while (current.GetNextNode() != null)
            {
                if (indexIter >= index)
                {
                    array[indexArray] = current.Item;
                    indexArray++;
                    count--;
                    if (count == 0)
                    {
                        return;
                    }
                }

                indexIter++;
            }

            /*
             * foreach (AvlNode<T> node in this.Nodes())
             * {
             *  if (indexIter >= index)
             *  {
             *      array[indexArray] = node.Item;
             *      indexArray++;
             *      count--;
             *      if (count == 0)
             *      {
             *          return;
             *      }
             *  }
             *
             *  indexIter++;
             * }*/
        }