// Read through lists to find the path.
public void FindPath(AiBotBase bot, Player plr, Level level)
{
if (data.Count == 0)
return;
path = new List<Coord2>();
int lowest = int.MaxValue;
Coord2 currentPos = new Coord2(-1, -1);
Coord2 nextPos = new Coord2(bot.GridPosition.X, bot.GridPosition.Y);
while (Math.Abs(plr.GridPosition.X - currentPos.X) > 1 || Math.Abs(plr.GridPosition.Y - currentPos.Y) > 1)//(new Coord2(plr.GridPosition.X, plr.GridPosition.Y-1) != currentPos)
{
currentPos = nextPos;
if (data[(plr.GridPosition.X) * level.GridSizeX + plr.GridPosition.Y].ElementAt((currentPos.X) * level.GridSizeY + (currentPos.Y)) != 0 ||
data[(plr.GridPosition.X) * level.GridSizeX + plr.GridPosition.Y].ElementAt((currentPos.X) * level.GridSizeY + (currentPos.Y)) < int.MaxValue)
{
for (int i = -1; i <= 1; i++)
for (int j = -1; j <= 1; j++)
if (level.ValidPosition(new Coord2(currentPos.X + i, currentPos.Y + j)))
if (data[plr.GridPosition.X * 40 + plr.GridPosition.Y].ElementAt((currentPos.X + i) * 40 + (currentPos.Y + j)) < lowest)
//if (i == 0 || j == 0)
if (new Coord2(currentPos.X + i, currentPos.Y + j) != new Coord2(currentPos.X, currentPos.Y))
{
lowest = data[plr.GridPosition.X * 40 + plr.GridPosition.Y].ElementAt((currentPos.X + i) * 40 + (currentPos.Y + j));
nextPos = new Coord2(currentPos.X + i, currentPos.Y + j);
}
}
if (lowest == int.MaxValue)
break;
path.Add(nextPos);
}
}
protected override void ChooseNextGridLocation(Level level, Player plr)
{
//your code will go here.
Coord2 position;
position = GridPosition;
if(plr.GridPosition.X < position.X)//if player position X less than bot position X move back on the X axis
{
//position.X -= 1;
}
if (plr.GridPosition.X > position.X)//if player position X greater then bot position X move forward on the X axis.
{
//position.X += 1;
}
if (plr.GridPosition.Y < position.Y)//if player position Y less than bot position Y move down on the Y axis.
{
//position.Y -= 1;
}
if (plr.GridPosition.Y > position.Y)//if player position Y greater than bot position Y move up on the Y axis.
{
//position.Y += 1;
}
SetNextGridPosition(position, level);//sets position of bot.
level.ValidPosition(position);//checks for walls.
}
protected override void ChooseNextGridLocation(Level level, Player plr)
{
bool ok = false;
Coord2 pos;// = new Coord2();
while (!ok)
{
pos = GridPosition;
int x = rnd.Next(0,4);
switch (x)
{
case (0):
pos.X += 1;
break;
case (1):
pos.X -= 1;
break;
case (2):
pos.Y += 1;
break;
case (3):
pos.Y -= 1;
break;
}
ok = SetNextGridPosition(pos, level);
}
}
protected override void ChooseNextGridLocation(Level level, Player plr)
{
double currentDistance = GetDistance(plr.GridPosition, GridPosition);
Coord2 testPosition = new Coord2(GridPosition.X, GridPosition.Y);
for (int i = -1; i <= 1; i++)
{
for (int j = -1; j <= 1; j++)
{
if (i == 0 || j == 0)
{
testPosition = new Coord2(GridPosition.X + i, GridPosition.Y + j);
if (currentDistance > GetDistance(plr.GridPosition, testPosition))
{
currentDistance = GetDistance(plr.GridPosition, testPosition);
SetNextGridPosition(testPosition, level);
currentDirection = testPosition - GridPosition;
}
}
}
}
if (!level.ValidPosition(GridPosition + currentDirection))
{
currentDirection = new Coord2(currentDirection.Y, currentDirection.X);
SetNextGridPosition(GridPosition + currentDirection, level);
}
}
//Handles animation moving from current grid position (gridLocation) to next grid position (targetLocation)
//When target location is reached, sets grid location to targetLocation, and then calls ChooseNextGridLocation
//and resets animation timer
public void Update(GameTime gameTime, Level level, Player plr)
{
timerMs -= gameTime.ElapsedGameTime.Milliseconds;
if (timerMs <= 0)
{
gridPosition = targetPosition;
ChooseNextGridLocation(level, plr);
timerMs = moveTime;
}
//calculate screen position
screenPosition = (gridPosition * 15) + ((((targetPosition * 15) - (gridPosition * 15)) * (moveTime - timerMs)) / moveTime);
}
protected override void ChooseNextGridLocation(Level level, Player plr)
{
Coord2 position;
position = GridPosition;
if (plr.GridPosition.X < position.X)
{
position.X -= 1;
}
if (plr.GridPosition.X > position.X)
{
position.X += 1;
}
if (plr.GridPosition.Y < position.Y)
{
position.Y -= 1;
}
if (plr.GridPosition.Y > position.Y)
{
position.Y += 1;
}
if (!level.ValidPosition(position))
{
if (plr.GridPosition.Y < position.Y)
{
position = GridPosition;
position.Y -= 1;
SetNextGridPosition(position, level);
}
if (plr.GridPosition.Y > position.Y)
{
position = GridPosition;
position.Y += 1;
SetNextGridPosition(position, level);
}
if (plr.GridPosition.X > position.X)
{
position = GridPosition;
position.X -= 1;
SetNextGridPosition(position, level);
}
if (plr.GridPosition.X < position.X)
{
position = GridPosition;
position.X += 1;
SetNextGridPosition(position, level);
}
}
SetNextGridPosition(position, level);//sets position of bot.
}
protected override void ChooseNextGridLocation(Level level, Player plr)
{
Coord2 CurrentPos;
if(level.build_astar == true)
{
CurrentPos = GridPosition;
//sets new position for the bot.
if (GridPosition != plr.GridPosition)
{
CurrentPos = level.astar.astar_path[index];
}
SetNextGridPosition(CurrentPos, level);
index++;
}
}
protected override void ChooseNextGridLocation(Map level, Player plr)
{
try
{
if (level.pathfinder.GetAlgorithm() != PathfinderAlgorithm.ScentMap)
throw new Exception("Wrong bot used for pathfinding algorithm.");
// Get a copy of the scent map
ScentMap map = (level.pathfinder as ScentMap);
// Get neighbouring coordinates
Coord2[] neighbours = GetNeighbours();
Coord2 highest = new Coord2(0, 0);
bool validFound = false;
for (int i = 0; i < neighbours.Length; i++) // Ensures a valid position is initially selected
{
if (level.ValidPosition(neighbours[i]))
{
highest = neighbours[i];
validFound = true;
break;
}
}
if (validFound) // Only update if at least one neighbouring positon is in fact valid on the map
{
// Find the highest neighbouring coorindate
for (int i = 0; i < neighbours.Length; i++)
{
if (level.ValidPosition(neighbours[i]))
{
if (map.Scents.data[neighbours[i].X, neighbours[i].Y] > map.Scents.data[highest.X, highest.Y])
highest = neighbours[i];
}
}
SetNextGridPosition(highest, level);
}
}
catch (Exception e)
{
Console.WriteLine("Bot Exception: " + e.Message);
}
}
// Create a text file by flooding Dijkstra's for every cell.
public void Calculate(Level level)
{
int firstTile = level.tiles[0][0];
level.tiles[0][0] = 1;
Dijkstra dijkstra = new Dijkstra(level);
AiBotSimple bot = new AiBotSimple(0,0);
Player player = new Player(level.GridSizeX-1, level.GridSizeY-1);
Coord2 current = new Coord2(-1, -1);
dijkstra.Build(level, bot, player);
StreamWriter writer = new StreamWriter("precompute.txt", true);
for (int x = 0; x < level.GridSize; x++)
{
for (int y = 0; y < level.GridSize; y++)
{
for (int i = 0; i < level.GridSize; i++)
{
for (int j = 0; j < level.GridSize; j++)
{
if (new Coord2(i, j) == player.GridPosition)
writer.Write(0);
else if (level.ValidPosition(new Coord2(i, j)) && dijkstra.cost[i,j].ToString() != "2.147484E+09")
writer.Write(dijkstra.cost[i, j].ToString());
else
writer.Write("-");
string tab = "\t";
writer.Write(tab);
}
}
writer.WriteLine();
bot = new AiBotSimple(x, y);
player = new Player(0, 0);
dijkstra = new Dijkstra(level);
dijkstra.Build(level, bot, player);
}
}
writer.Close();
level.tiles[0][0] = firstTile;
}
// Read base class's input class and follow through.
protected override void ChooseNextGridLocation(Level level, Player plr)
{
if (path == null)
{
if (dijkstra != null)
path = dijkstra.path;
else if (aStar != null)
path = aStar.path;
else if (level.precompute != null)
{
path = level.precompute.path;
path.Reverse();
}
}
else if (path.Count > 0)
{
SetNextGridPosition(path[path.Count-1], level);
path.RemoveAt(path.Count - 1);
}
}
protected override void ChooseNextGridLocation(Map level, Player plr)
{
//Coord2[] neighbours = GetNeighbours();
//int cVal = 0;
//Coord2 cPos = new Coord2(0, 0);
//for (int i = 0; i < neighbours.Length; i++)
//{
// if(level.ValidPosition(neighbours[i]))
// {
// int lVal = level.scentMap.Buffer1.data[neighbours[i].X, neighbours[i].Y];
// if (lVal > cVal)
// {
// cVal = lVal;
// cPos = new Coord2(neighbours[i].X, neighbours[i].Y);
// }
// }
//}
//SetNextGridPosition(cPos, level);
}
//this function is filled in by a derived class: must use SetNextGridLocation to actually move the bot
protected override void ChooseNextGridLocation(Map level, Player plr)
{
try
{
if (level.pathfinder.GetAlgorithm() != PathfinderAlgorithm.AStar && level.pathfinder.GetAlgorithm() != PathfinderAlgorithm.Dijkstra)
throw new Exception("Wrong bot used for pathfinding algorithm.");
List<Coord2> path = level.pathfinder.GetPath();
if (path.Count > 0 && currentPathIndex != path.Count - 1)
{
SetNextGridPosition(path[currentPathIndex], level);
currentPathIndex++;
}
else
currentPathIndex = 0;
}
catch(Exception e)
{
Console.WriteLine("Bot Exception: " + e.Message);
}
}
// Follow the highest adjacent scent value.
protected override void ChooseNextGridLocation(Level level, Player plr)
{
if (GridPosition == plr.GridPosition)
return;
Coord2 next = new Coord2(-1, -1);
int highest = 0;
for (int i = -1; i <= 1; i++)
{
for (int j = -1; j <= 1; j++)
{
if (level.ValidPosition(new Coord2(GridPosition.X+i, GridPosition.Y+j)) &&
plr.GetScent(GridPosition.X + i, GridPosition.Y + j) > highest && (i == 0 || j == 0))
{
if (i == 0 && j == 0)
continue;
highest = plr.GetScent(GridPosition.X + i, GridPosition.Y + j);
next = new Coord2(GridPosition.X + i, GridPosition.Y + j);
}
}
}
SetNextGridPosition(next, level);
}
protected override void ChooseNextGridLocation(Level level, Player plr)
{
Coord2 CurrentPos;
CurrentPos = GridPosition;
//checks bot surrounding nodes.
if(GridPosition != plr.GridPosition)
{
for (int f = -1; f <= 1; f++)
{
for (int g = -1; g <= 1; g++)
{
//changes bot position.
if (level.scentmap.buffer1[GridPosition.X + f, GridPosition.Y + g] > level.scentmap.buffer1[GridPosition.X, GridPosition.Y])
{
CurrentPos = new Coord2(GridPosition.X + f, GridPosition.Y + g);
level.path_count ++;
}
SetNextGridPosition(CurrentPos, level);
}
}
}
}
public void Update(Level level, Player plr)
{
try
{
sourceValue++;
}
catch
{
throw new Exception("A billion years passed and this somehow overflowed.");
}
// Make buffers identical.
Array.Copy(bufferOne, bufferTwo, bufferTwo.Length);
bufferOne[plr.GridPosition.X, plr.GridPosition.Y] = sourceValue;
bufferTwo[plr.GridPosition.X, plr.GridPosition.Y] = sourceValue;
// Iterate through cells, using one buffer for comparison and another for updating.
for (int x = 0; x < level.GridSize; x++)
{
for (int y = 0; y < level.GridSize; y++)
{
for (int i = -1; i <= 1; i++)
{
for (int j = -1; j <= 1; j++)
{
if (level.ValidPosition(new Coord2(x + i, y + j))
&& (level.ValidPosition(new Coord2(x+i, y)) && level.ValidPosition(new Coord2(x, y+j))))
{
if ((bufferOne[x, y] < bufferTwo[x + i, y + j]))
bufferOne[x, y] = bufferTwo[x+i,y+j] - 1;
}
}
}
}
}
}
//this function is filled in by a derived class: must use SetNextGridLocation to actually move the bot protected abstract void ChooseNextGridLocation(Level level, Player plr);
protected override void ChooseNextGridLocation(Level level, Player plr)
{
}
public Game1()
{
//program settings.
Window.Title = "GAL11266257_CGP3001M_Assignment 2";
graphics = new GraphicsDeviceManager(this);
graphics.PreferredBackBufferHeight = BackBufferHeight;
graphics.PreferredBackBufferWidth = BackBufferWidth;
Content.RootDirectory = "../../../Content";
TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / TargetFrameRate);
//loads map.
level = new Level();
level.Loadmap("../../../Content/0.txt");
//loads player.
player = new Player(125, 67);
}
//generates path.
public void Build(Level level, AiBotBase bot, Player plr)
{
//starts timing the algorithm.
var watch = Stopwatch.StartNew();
astar_is_built = true;
astar_built = true;
//fill nodes with default value.
for (int i = 0; i < map_size; i++)
{
for (int j = 0; j < map_size; j++)
{
closed[i, j] = false;
cost[i, j] = 999999;
link[i, j] = new Coord2(-1, -1);
inPath[i, j] = false;
}
}
open_locations.Add(bot.GridPosition);
Coord2 lowest_location = new Coord2(-1, -1);
float lowest_cost = 999999;
float newcost = 999999;
closed[bot.GridPosition.X, bot.GridPosition.Y] = false;
cost[bot.GridPosition.X, bot.GridPosition.Y] = 0;
//heuristic calculation
for (int i = 0; i < map_size; i++)
{
for (int j = 0; j < map_size; j++)
{
if (level.manhatten == true)
{
heuristic[i, j] = Math.Abs(i - plr.GridPosition.X) + Math.Abs(j - plr.GridPosition.Y);//manhatten.
}
else if (level.diagonal == true)
{
heuristic[i, j] = Math.Max(Math.Abs(i - plr.GridPosition.X), Math.Abs(j - plr.GridPosition.Y));//diagonal.
}
else if (level.euclidian == true)
{
heuristic[i, j] = (int)Math.Sqrt(Math.Pow(i - plr.GridPosition.X, 2) + Math.Pow(j - plr.GridPosition.Y, 2));//euclidian.
}
else
{
heuristic[i, j] = Math.Abs(i - plr.GridPosition.X) + Math.Abs(j - plr.GridPosition.Y);//manhatten is the default heuristic.
}
}
}
while (!closed[plr.GridPosition.X, plr.GridPosition.Y])
{
lowest_cost = 999999;
//unoptomised astar.
if (level.astar_unoptomised_chosen == true)
{
for (int x = 0; x < map_size; x++)
{
for (int y = 0; y < map_size; y++)
{
if (cost[x, y] + heuristic[x, y] < lowest_cost && !closed[x, y])
{
lowest_cost = cost[x, y] + heuristic[x, y];
lowest_location = new Coord2(x, y);
}
}
}
}
else
{
//optomised astar, only checks open locations.
for (int x = 0; x < open_locations.Count(); x++)
{
if ((cost[open_locations[x].X, open_locations[x].Y] + heuristic[open_locations[x].X, open_locations[x].Y]) < lowest_cost && !closed[open_locations[x].X, open_locations[x].Y])
{
lowest_cost = cost[open_locations[x].X, open_locations[x].Y] + heuristic[open_locations[x].X, open_locations[x].Y];
lowest_location = new Coord2(open_locations[x].X, open_locations[x].Y);
}
}
}
closed[lowest_location.X, lowest_location.Y] = true;
open_locations.Remove(lowest_location);
//counts nodes closed.
if (closed[lowest_location.X, lowest_location.Y] == true)
{
isClosed ++;
}
for (int f = -1; f <= 1; f++)
{
for (int g = -1; g <= 1; g++)
{
//assigns a cost to each location surrounding the current path node.
if (level.ValidPosition(new Coord2(lowest_location.X + f, lowest_location.Y + g)))
{
newcost = 999999;
Coord2 neighbour_location;
neighbour_location = new Coord2(lowest_location.X + f, lowest_location.Y + g);
if (f != 0 ^ g != 0)
{
//horizontal cost.
newcost = 1f;
}
else if (f != 0 && g != 0)
{
//diagonal cost.
newcost = 1.4f;
}
if (!open_locations.Contains(neighbour_location) && neighbour_location != bot.GridPosition)
{
open_locations.Add(neighbour_location);
}
if (newcost < cost[lowest_location.X + f, lowest_location.Y + g] && level.ValidPosition(new Coord2(lowest_location.X + f, lowest_location.Y + g)) && !closed[lowest_location.X + f, lowest_location.Y + g])
{
cost[lowest_location.X + f, lowest_location.Y + g] = newcost;//assigns current cost to the new cost.
link[lowest_location.X + f, lowest_location.Y + g] = new Coord2(lowest_location.X, lowest_location.Y);//assigns current link to lowest location.
}
}
}
}
}
bool done = false;
Coord2 nextclosed = plr.GridPosition;
while (done == false)
{
//adds next step to path.
astar_path.Add(nextclosed);
inPath[nextclosed.X, nextclosed.Y] = true;
nextclosed = link[nextclosed.X, nextclosed.Y];
if (nextclosed == bot.GridPosition)
{
astar_path.Add(bot.GridPosition);//adds path to the bot.
done = true;
}
}
astar_path.Reverse();//reverse path for reading.
watch.Stop();
elapsedMS = watch.ElapsedMilliseconds;
}
public Level(Map map, Player plr, AiBotBase bot)
{
this.map = map;
this.player = plr;
this.bot = bot;
}
protected override void ChooseNextGridLocation(Map level, Player plr)
{
SetNextGridPosition(gridPosition, level);
}
// Generate the path.
public void Build(Level level, AiBotBase bot, Player plr)
{
cost[bot.GridPosition.X, bot.GridPosition.Y] = 0;
Coord2 currentPosition = bot.GridPosition;
closed[bot.GridPosition.X, bot.GridPosition.Y] = true;
while (!closed[plr.GridPosition.X, plr.GridPosition.Y])
{
// Open adjacent cells.
for (int i = -1; i <= 1; i++)
{
for (int j = -1; j <= 1; j++)
{
if (level.ValidPosition(new Coord2(currentPosition.X + i, currentPosition.Y + j)) && !closed[currentPosition.X + i, currentPosition.Y + j]
&& (i != 0 || j != 0) && (currentPosition.X + i < level.GridSize && currentPosition.Y + j < level.GridSize && currentPosition.X + i >= 0 && currentPosition.Y + j >= 0)
&& (level.ValidPosition(new Coord2(currentPosition.X + i, currentPosition.Y)) && level.ValidPosition(new Coord2(currentPosition.X, currentPosition.Y + j))))
{
if (i == 0 || j == 0)
SetCost(currentPosition, level, i, j, false);
else
SetCost(currentPosition, level, i, j, true);
}
}
}
float lowestCost = int.MaxValue;
Coord2 nextPosition = currentPosition;
// Iterate through the list to check open cells for valid movements.
for (int i = 0; i < level.GridSize; i++)
{
for (int j = 0; j < level.GridSize; j++)
{
if (!closed[i, j] && level.ValidPosition(new Coord2(i, j)) && cost[i, j] < lowestCost)
{
lowestCost = cost[i, j];
nextPosition = new Coord2(i, j);
}
}
}
if (currentPosition == nextPosition)
break;
closed[nextPosition.X, nextPosition.Y] = true;
currentPosition = nextPosition;
}
bool done = false;
Coord2 nextClose = plr.GridPosition;
while (!done)
{
if (nextClose.X == -1)
break;
if (nextClose == bot.GridPosition)
{
playerPos = plr.GridPosition;
done = true;
}
inPath[nextClose.X, nextClose.Y] = true;
path.Add(new Coord2(nextClose.X, nextClose.Y));
nextClose = link[nextClose.X, nextClose.Y];
}
}
public Game1()
{
//constructor
graphics = new GraphicsDeviceManager(this);
graphics.PreferredBackBufferHeight = BackBufferHeight;
graphics.PreferredBackBufferWidth = BackBufferWidth;
Window.Title = "Pathfinder";
Content.RootDirectory = "Content";
this.IsMouseVisible = true;
this.IsFixedTimeStep = false;
elapsedTime = 0;
frameCounter = 0;
FPS = 60;
mouseState = Mouse.GetState();
lastMouseState = mouseState;
mouseClickPos = new Coord2(-1, -1);
scrollOffset = Vector2.Zero;
textColour = Color.BlueViolet;
//set frame rate
TargetElapsedTime = TimeSpan.FromTicks(TimeSpan.TicksPerSecond / TargetFrameRate);
//load level map
level = new Level();
string mapName = mapNumber.ToString();
//mapName = "eighty";
level.Loadmap("Content/" + mapName + ".txt");
//instantiate bot and player objects
BackBufferWidth = level.gridSquareSize * level.GridSizeX;
BackBufferHeight = level.GridSizeY * level.GridSquareSize;
graphics.PreferredBackBufferHeight = BackBufferHeight;
graphics.PreferredBackBufferWidth = BackBufferWidth;
graphics.ApplyChanges();
graphics.GraphicsDevice.Reset();
SetCharacters();
//bots = new List<AiBotBase>();
#if ASTARTEST
string heuristic = "Euclidean";
StreamWriter r = new StreamWriter("astarTest-" + mapName + "-" + heuristic + ".txt");
r.WriteLine("A Star Test values with " + heuristic);
r.WriteLine("Map size: {0}x{1}", level.GridSizeX, level.GridSizeY);
r.WriteLine("Times per build, in ms");
AStar aStar = new AStar(level);
aStar = new AStar(level);
Stopwatch timer = new Stopwatch();
Coord2 start = new Coord2(1, 1);
Coord2 end = new Coord2(level.GridSizeX-1, level.GridSizeY-1);
for (int i = 0; i < 1000; i++)
{
timer.Restart();
aStar.Build(level, start, end, false, heuristic);
timer.Stop();
r.WriteLine("{0:N3}", timer.Elapsed.TotalMilliseconds);
}
r.Close();
#endif
#if DIJKSTRASTEST
StreamWriter r = new StreamWriter("dijkstrasTest-" + mapName + ".txt");
string mapDescription = "";
r.WriteLine("Dijkstra's Test values");
r.WriteLine("Map size: {0}x{1}", level.GridSizeX, level.GridSizeY);
r.WriteLine(mapDescription);
r.WriteLine("Times per build, in ms");
Dijkstra dijkstras = new Dijkstra(level);
dijkstras = new Dijkstra(level);
Stopwatch timer = new Stopwatch();
AiBotAlgorithm bot = new AiBotAlgorithm(1, 1);
Player player = new Player(level.GridSizeX - 1, level.GridSizeY - 1);
for (int i = 0; i < 1000; i++)
{
timer.Restart();
dijkstras.Build(level, bot, player);
timer.Stop();
r.WriteLine("{0:N3}", timer.Elapsed.TotalMilliseconds);
}
r.Close();
#endif
#if PRECOMPUTETEST
StreamWriter r = new StreamWriter("precomputeTest-" + mapName + ".txt");
string mapDescription = "";
r.WriteLine("Precompute's Test values");
r.WriteLine("Map size: {0}x{1}", level.GridSizeX, level.GridSizeY);
r.WriteLine(mapDescription);
r.WriteLine("Times per build, in ms");
Precompute precompute = new Precompute(mapName);
precompute = new Precompute(mapName);
Stopwatch timer = new Stopwatch();
AiBotAlgorithm bot = new AiBotAlgorithm(1, 1);
Player player = new Player(level.GridSizeX - 1, level.GridSizeY - 1);
for (int i = 0; i < 1; i++)
{
timer.Restart();
precompute.Calculate(level);
timer.Stop();
r.WriteLine("{0:N3}", timer.Elapsed.TotalMilliseconds);
}
r.Close();
#endif
}
private void SetCharacters(int bX = 1, int bY = 1, int pX = 10, int pY = 10)
{
bots = new List<AiBotBase>();
//bots[0] = new AiBotStill(bX, bY);
bots.Add(new AiBotStill(bX, bY));
bots[0].dijkstra = null;
bots[0].aStar = null;
player = new Player(pX, pY);
methodText = "None";
}
//generates path.
public void Build(Level level, AiBotBase bot, Player plr)
{
//starts timing the algorithm.
var watch = Stopwatch.StartNew();
dijkstra_is_built = true;
dijkstra_built = true;
//fill nodes with default value.
for (int i = 0; i < map_size; i++)
{
for (int j = 0; j < map_size; j++)
{
closed[i, j] = false;
cost[i, j] = float.MaxValue;
link[i, j] = new Coord2(-1, -1);
inPath[i, j] = false;
}
}
Coord2 lowest_location = new Coord2 (-1, -1);
float lowest_cost = float.MaxValue;
closed[bot.GridPosition.X, bot.GridPosition.Y] = false;
cost[bot.GridPosition.X, bot.GridPosition.Y] = 0;
while (!closed[plr.GridPosition.X, plr.GridPosition.Y])
{
lowest_cost = float.MaxValue;
for (int x = 0; x < map_size; x++)
{
for (int y = 0; y < map_size; y++)
{
//sets new lowest cost.
if(cost[x,y] <= lowest_cost && !closed[x, y])
{
lowest_cost = cost[x, y];
lowest_location = new Coord2(x, y);
}
}
}
//closes that node.
closed[lowest_location.X, lowest_location.Y] = true;
//counts nodes closed.
if(closed[lowest_location.X, lowest_location.Y] == true)
{
isClosed ++;
}
for (int f = -1; f <= 1; f++)
{
for (int g = -1; g <= 1; g++)
{
//assigns a cost to each location surrounding the current path node.
if(level.ValidPosition(new Coord2(lowest_location.X + f, lowest_location.Y + g)))
{
float newcost = float.MaxValue;
if(f != 0 ^ g != 0)
{
//horizontal cost.
newcost = lowest_cost + 1f;
}
else if (f != 0 && g != 0)
{
//diagonal cost.
newcost = lowest_cost + 1.4f;
}
if(newcost < cost[lowest_location.X + f, lowest_location.Y + g] && level.ValidPosition(new Coord2(lowest_location.X + f, lowest_location.Y + g)))
{
cost[lowest_location.X + f, lowest_location.Y + g] = newcost;//assigns current cost to the new cost.
link[lowest_location.X + f, lowest_location.Y + g] = new Coord2(lowest_location.X, lowest_location.Y);//assigns current link to lowest location.
}
}
}
}
}
bool done = false;
nextclosed = plr.GridPosition;
while (done == false)
{
//adds next step to path.
dijkstra_path.Add(nextclosed);
inPath[nextclosed.X, nextclosed.Y] = true;
nextclosed = link[nextclosed.X, nextclosed.Y];
if (nextclosed == bot.GridPosition)
{
dijkstra_path.Add(bot.GridPosition);//adds path to the bot.
done = true;
}
}
dijkstra_path.Reverse();//reverse path for reading.
elapsedMS = watch.ElapsedMilliseconds;
}