private bool IsOpen(AStarGridNode node)
{
IEnumerator enumerator = mOpenTable.GetEnumerator();
try
{
while (enumerator.MoveNext())
{
AStarGridNode current = (AStarGridNode)enumerator.Current;
if (current.Equals(node))
{
return(true);
}
}
}
finally
{
IDisposable disposable = enumerator as IDisposable;
if (disposable == null)
{
}
disposable.Dispose();
}
return(false);
}
/// <summary>
/// 构建路径信息
/// </summary>
private void BuildPath()
{
Path.Clear();
for (AStarGridNode node = Grid.EndNode; false == node.Equals(Grid.StartNode); node = node.ParentNode)
{
Path.Add(node);
}
}
private bool Search()
{
AStarGridNode startNode = Grid.StartNode;
// 还没有遍历到最后一个节点
while (false == startNode.Equals(Grid.EndNode))
{
int num = (int)Math.Max((float)0f, (float)(startNode.Position.x - 1f));
int num2 = (int)Math.Min((float)(Grid.NumCols - 1), startNode.Position.x + 1f);
int num3 = (int)Math.Max((float)0f, (float)(startNode.Position.y - 1f));
int num4 = (int)Math.Min((float)(Grid.NumRows - 1), startNode.Position.y + 1f);
for (int i = num; i <= num2; i++)
{
for (int j = num3; j <= num4; j++)
{
AStarGridNode nodeAtPosition = Grid.GetNodeAtPosition(i, j);
// 剔除重复的节点
if (false == nodeAtPosition.Equals(startNode) && nodeAtPosition.Walkable)
{
double straightCost = mStraightCost;
if ((startNode.Position.x != nodeAtPosition.Position.x) && (startNode.Position.y != nodeAtPosition.Position.y))
{
straightCost = mDiagonalCost;
}
double num8 = startNode.G + (straightCost * nodeAtPosition.Cost);
double heruistic = GetHeruistic(nodeAtPosition);
double num10 = num8 + heruistic;
// 已经在open或者close表中
if (IsOpen(nodeAtPosition) || IsClosed(nodeAtPosition))
{
if (nodeAtPosition.F > num10)
{
nodeAtPosition.F = num10;
nodeAtPosition.G = num8;
nodeAtPosition.H = heruistic;
nodeAtPosition.ParentNode = startNode;
}
}
// 不在这些表中
else
{
nodeAtPosition.F = num10;
nodeAtPosition.G = num8;
nodeAtPosition.H = heruistic;
nodeAtPosition.ParentNode = startNode;
mOpenTable.Add(nodeAtPosition);
}
}
}
}
// 已经走过该节点
mClosedTable.Add(startNode);
// 检查是否没有需要走的节点了
if (mOpenTable.Count == 0)
{
return(false);
}
// 排序open表提高效率
mOpenTable.Sort(new AStarComparer());
// 获取第一个节点然后从open表中删除
startNode = (AStarGridNode)mOpenTable[0];
mOpenTable.RemoveAt(0);
}
BuildPath();
return(true);
}
