游戏之寻路算法
玩游戏的人，都知道游戏中有自动寻路功能，鼠标点击想要到达的终点，主角则会自动走最短的一条路当然同时躲避障碍物，好了，不用多说，直接看效果吧（直观）。
绿色表示起点，红色表示终点，蓝色表示障碍物，而会动的表示从起点运动到终点的轨迹。
上面用的是寻路算法之曼哈顿算法，具体的表述可以参看http://hi.baidu.com/myfcag/blog/item/48bd91fd012a0bf6fd037fc5.html。别人翻译的很好，完全可以根据他的表述实现自己的寻路算法。下面再贴一张游戏的截面（特别申明：图中的素材全部来源于网络 ）
截图的效果不太好，不过可以看到主角在后面的移动中可以穿过草丛，因为这里还没加上障碍物的定位和寻路代码，这一部分主要是看看效果，在以后的时间里会贴出完整的代码。（是不是发现游戏的人物是仙剑二中的主角，
仙剑经典啊！）
贴上完整的寻路代码（下面的代码加入了一些在实际应用中的限制程序，理解主要的思想就OK了）：
代码
///
<summary>
/// 寻路
/// </summary>
public List < Point > PathFinding(Point startPos, Point endPos)
{
List < Point > ps = new List < Point > ();
int width = Matrix.GetLength( 0 );
int height = Matrix.GetLength( 1 );
// 起点
startEB = new Entity(startPos);
startEB.Par = null ;
// 终点
endEB = new Entity(endPos);
// 起点加入到开始列表中
startList.Add(startEB.Pos, startEB);
Entity s = startList[startEB.Pos]; // 起点
if (s.Pos == endEB.Pos) return ps;
// 起点的八方向（为代码方便阅读，将8个方向单独处理）
Entity temp = new Entity();
Point point = new Point();
bool upBarrier = false ;
bool downBarrier = false ;
bool leftBarrier = false ;
bool rightBarrier = false ;
while (s != null )
{
#region 初始化
upBarrier = false ;
downBarrier = false ;
leftBarrier = false ;
rightBarrier = false ;
#endregion
// ****右
point = new Point(s.Pos.X + 1 , s.Pos.Y);
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point); // (*待判断是否越界)
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else // 格子已经包括在开始列表中
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point)) // 右边有障碍物
{
rightBarrier = true ;
}
}
// ****上
point = new Point(s.Pos.X, s.Pos.Y - 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point)) // 上边有障碍物
{
upBarrier = true ;
}
}
// ****左
point = new Point(s.Pos.X - 1 , s.Pos.Y);
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point)) // 左边有障碍物
{
leftBarrier = true ;
}
}
// ****下
point = new Point(s.Pos.X, s.Pos.Y + 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point))
{
downBarrier = true ;
}
}
// ****右上
point = new Point(s.Pos.X + 1 , s.Pos.Y - 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! rightBarrier && ! upBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity( new Point(s.Pos.X + 1 , s.Pos.Y - 1 ));
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// ****右下
point = new Point(s.Pos.X + 1 , s.Pos.Y + 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! rightBarrier && ! downBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// ****左上
point = new Point(s.Pos.X - 1 , s.Pos.Y - 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! leftBarrier && ! upBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// ****左下
point = new Point(s.Pos.X - 1 , s.Pos.Y + 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! leftBarrier && ! downBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// 从开始列表中删除起点，并将其加到关闭列表中
if (startList.ContainsKey(s.Pos))
{
startList.Remove(s.Pos);
}
if ( ! closeList.ContainsKey(s.Pos))
{
closeList.Add(s.Pos, s);
}
// 寻找F值最低的
double fMin = Double.MaxValue ;
foreach (KeyValuePair < Point, Entity > key in startList)
{
if (key.Value.F <= fMin)
{
fMin = key.Value.F;
temp = key.Value;
}
}
// 将最低的从开始列表中删除，加载到关闭列表中
if (startList.ContainsKey(temp.Pos))
{
startList.Remove(temp.Pos);
}
if ( ! closeList.ContainsKey(temp.Pos))
{
closeList.Add(temp.Pos, temp);
}
// 判断是否需要继续查找
if (closeList.ContainsKey(endEB.Pos) || startList.Count <= 0 )
{
// 如果F值最低的点就是目标点，停止查找
s = null ;
}
else
{
s = temp;
}
}
// 返回值
return ps;
}
/// 寻路
/// </summary>
public List < Point > PathFinding(Point startPos, Point endPos)
{
List < Point > ps = new List < Point > ();
int width = Matrix.GetLength( 0 );
int height = Matrix.GetLength( 1 );
// 起点
startEB = new Entity(startPos);
startEB.Par = null ;
// 终点
endEB = new Entity(endPos);
// 起点加入到开始列表中
startList.Add(startEB.Pos, startEB);
Entity s = startList[startEB.Pos]; // 起点
if (s.Pos == endEB.Pos) return ps;
// 起点的八方向（为代码方便阅读，将8个方向单独处理）
Entity temp = new Entity();
Point point = new Point();
bool upBarrier = false ;
bool downBarrier = false ;
bool leftBarrier = false ;
bool rightBarrier = false ;
while (s != null )
{
#region 初始化
upBarrier = false ;
downBarrier = false ;
leftBarrier = false ;
rightBarrier = false ;
#endregion
// ****右
point = new Point(s.Pos.X + 1 , s.Pos.Y);
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point); // (*待判断是否越界)
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else // 格子已经包括在开始列表中
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point)) // 右边有障碍物
{
rightBarrier = true ;
}
}
// ****上
point = new Point(s.Pos.X, s.Pos.Y - 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point)) // 上边有障碍物
{
upBarrier = true ;
}
}
// ****左
point = new Point(s.Pos.X - 1 , s.Pos.Y);
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point)) // 左边有障碍物
{
leftBarrier = true ;
}
}
// ****下
point = new Point(s.Pos.X, s.Pos.Y + 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1 < exist.G)
{
exist.Par = s;
exist.G = 1 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
else
{
if (barrier.ContainsKey(point))
{
downBarrier = true ;
}
}
// ****右上
point = new Point(s.Pos.X + 1 , s.Pos.Y - 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! rightBarrier && ! upBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity( new Point(s.Pos.X + 1 , s.Pos.Y - 1 ));
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// ****右下
point = new Point(s.Pos.X + 1 , s.Pos.Y + 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! rightBarrier && ! downBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// ****左上
point = new Point(s.Pos.X - 1 , s.Pos.Y - 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! leftBarrier && ! upBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// ****左下
point = new Point(s.Pos.X - 1 , s.Pos.Y + 1 );
if ( ! barrier.ContainsKey(point) && ! closeList.ContainsKey(point) && (point.X < width && point.Y < height)) // 排除障碍物
{
if ( ! leftBarrier && ! downBarrier)
{
if ( ! startList.ContainsKey(point))
{
temp = new Entity(point);
temp.Par = s;
temp.G = 1.4 ;
temp.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
temp.F = temp.G + temp.H;
startList.Add(point, temp);
}
else
{
Entity exist = startList[point];
if (s.G + 1.4 < exist.G)
{
exist.Par = s;
exist.G = 1.4 ;
exist.H = Math.Abs(point.X - endEB.Pos.X) + Math.Abs(point.Y - endEB.Pos.Y);
exist.F = exist.G + exist.H;
}
}
}
}
// 从开始列表中删除起点，并将其加到关闭列表中
if (startList.ContainsKey(s.Pos))
{
startList.Remove(s.Pos);
}
if ( ! closeList.ContainsKey(s.Pos))
{
closeList.Add(s.Pos, s);
}
// 寻找F值最低的
double fMin = Double.MaxValue ;
foreach (KeyValuePair < Point, Entity > key in startList)
{
if (key.Value.F <= fMin)
{
fMin = key.Value.F;
temp = key.Value;
}
}
// 将最低的从开始列表中删除，加载到关闭列表中
if (startList.ContainsKey(temp.Pos))
{
startList.Remove(temp.Pos);
}
if ( ! closeList.ContainsKey(temp.Pos))
{
closeList.Add(temp.Pos, temp);
}
// 判断是否需要继续查找
if (closeList.ContainsKey(endEB.Pos) || startList.Count <= 0 )
{
// 如果F值最低的点就是目标点，停止查找
s = null ;
}
else
{
s = temp;
}
}
// 返回值
return ps;
}
由于实际需要，在代码中加了少许的修改，理解主要实现的思路即可！！！