/// <summary>
/// Calculates the distance between each node
/// </summary>
/// <param name="from">The node to calculate from</param>
/// <param name="to">The Node to calculate to </param>
/// <returns>The distance in number of nodes away times 10</returns>
/// <example>
/// From 1,1 to 2,2 Returns 14 as the the hypotenus/distance of 1,1 is 1.4
/// then we multiply this by 10
/// </example>
public int distanceBetweenNodes(Node from, Node to)
{
int horDist = Math.Abs(to.positionX - from.positionX) / 32;
int vertDist = Math.Abs(to.positionY - from.positionY) / 32;
return (int)(Math.Sqrt(horDist * horDist + vertDist * vertDist)*10);
}
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
//Create a map of nodes
map = new Node[Window.ClientBounds.Width/32,Window.ClientBounds.Height/32];
for (int y = 0; y < map.GetLength(1); y++)
{
for (int x = 0; x < map.GetLength(0); x++)
{
map[x, y] = new Node(false, x*32, y*32, Color.Gray);
}
}
startNode = map[0, 0];
endNode = map[1, 1];
path = new List<Node>();
}
/// <summary>
/// Generate the heurstic value from node to end
/// </summary>
/// <param name="node">The node of which to generate the value</param>
/// <returns>The heuristic value</returns>
/// <remarks>Uses eucalean heuristic</remarks>
public int Heuristic(Node node)
{
int horDist = Math.Abs(endNode.positionX - node.positionX) / 32;
int vertDist = Math.Abs(endNode.positionY - node.positionY) / 32;
//return (int)Math.Sqrt(horDist * horDist + vertDist * vertDist)*10;
return ((horDist + vertDist != 0) ? (horDist + vertDist - 1) : 0)*10;
}
/// <summary>
/// Gets the neighboors of a node
/// </summary>
/// <param name="node">The node to find parent of</param>
/// <returns>An array containing arrays that are adjacent of the node</returns>
private Node[] getNeighboors(Node node)
{
int nodeIndexX = node.positionX/32;
int nodeIndexY = node.positionY/32;
List<Node> nodesAsNeighboors = new List<Node>();
for (int y = -1; y < 2; y++)
{
for (int x = -1; x < 2; x++)
{
//dont include ourselves
if (x == 0 && y == 0)
continue;
int xx = nodeIndexX + x;
int yy = nodeIndexY + y;
if (xx >= 0 && xx < map.GetLength(0) && yy >= 0 && yy < map.GetLength(1))
{
nodesAsNeighboors.Add(map[xx, yy]);
}
}
}
return nodesAsNeighboors.ToArray();
}
/// <summary>
/// Allows the game to run logic such as updating the world,
/// checking for collisions, gathering input, and playing audio.
/// </summary>
/// <param name="gameTime">Provides a snapshot of timing values.</param>
protected override void Update(GameTime gameTime)
{
this.gameTime = gameTime;
currentMouseState = Mouse.GetState();
currentKeyboard = Keyboard.GetState();
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
//Adds a wall
if (currentMouseState.LeftButton == ButtonState.Pressed &&
previousMouseState.LeftButton == ButtonState.Released)
{
int gridX = (int)MathHelper.Clamp(currentMouseState.X / 32,0,map.GetLength(0)-1);
int gridY = (int)MathHelper.Clamp(currentMouseState.Y / 32, 0, map.GetLength(1)-1);
map[gridX, gridY].color = Color.Black;
if (map[gridX, gridY].isWall)
{
map[gridX, gridY].isWall = false;
}
else
{
map[gridX, gridY].isWall = true;
}
}
//Change start and stop
if (currentMouseState.RightButton == ButtonState.Pressed &&
previousMouseState.RightButton == ButtonState.Released)
{
int gridX = currentMouseState.X / 32;
int gridY = currentMouseState.Y / 32;
startNode = map[gridX, gridY];
}
if (currentMouseState.MiddleButton == ButtonState.Pressed &&
previousMouseState.MiddleButton == ButtonState.Released)
{
int gridX = currentMouseState.X / 32;
int gridY = currentMouseState.Y / 32;
endNode = map[gridX, gridY];
}
//Generate map
if (currentKeyboard.IsKeyDown(Keys.Space) && previousKeyboard.IsKeyUp(Keys.Space))
{
generatePath();
}
//Reset the map
if (currentKeyboard.IsKeyDown(Keys.R) && previousKeyboard.IsKeyUp(Keys.R))
{
foreach (Node n in map)
{
n.isWall = false;
}
openNodes.Clear();
closedNodes.Clear();
path.Clear();
}
previousMouseState = Mouse.GetState();
previousKeyboard = Keyboard.GetState();
base.Update(gameTime);
}
