public Algorithm(TileWorld.TileWorld world)
{
this.world = world;
// Find the start and goalNode.
int startX = 0;
int startY = 0;
int goalX = 0;
int goalY = 0;
for (int x = 0; x < world.getWidth(); x++)
{
for (int y = 0; y < world.getHeight(); y++)
{
if (world.getTileType(x, y) == eTileType.START)
{
startX = x;
startY = y;
}
if (world.getTileType(x, y) == eTileType.END)
{
goalX = x;
goalY = y;
}
}
}
startNode = GetNode(startX, startY, world.getTileType(startX, startY));
goalNode = GetNode(goalX, goalY, world.getTileType(goalX, goalY));
startNode.cost = 0;
startNode.heuristic = CalculateHeuristic(startNode);
open.Add(startNode);
notDiscoveredYet.Add(goalNode);
}
/// <summary>
/// Returns a list with all the neighbours of the given node.
/// </summary>
/// <param name="node"></param>
/// <returns>List of neighbouring nodes</returns>
protected ArrayList GetNeighbourNodes(Node node)
{
ArrayList neighbours = new ArrayList();
/* Straight neightbours */
// If the node has a left neighbour.
if (node.x > 0)
{
int neighbourX = node.x - 1;
int neighbourY = node.y;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
// If the node has a right neighbour.
if (node.x < world.getWidth() - 1)
{
int neighbourX = node.x + 1;
int neighbourY = node.y;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
// If the node has a top neighbour.
if (node.y > 0)
{
int neighbourX = node.x;
int neighbourY = node.y - 1;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
// If the node has a bottom neighbour.
if (node.y < world.getHeight() - 1)
{
int neighbourX = node.x;
int neighbourY = node.y + 1;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
/* Diagonal neighbours */
// If the node has an upper left neighbour.
if (node.x > 0 && node.y > 0)
{
int neighbourX = node.x - 1;
int neighbourY = node.y - 1;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
// If the node has an upper right neighbour.
if (node.x < world.getWidth() - 1 && node.y > 0)
{
int neighbourX = node.x + 1;
int neighbourY = node.y - 1;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
// If the node has a bottom left neighbour.
if (node.x > 0 && node.y < world.getHeight() - 1)
{
int neighbourX = node.x - 1;
int neighbourY = node.y + 1;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
// If the node has a bottom right neighbour.
if (node.x < world.getWidth() - 1 && node.y < world.getHeight() - 1)
{
int neighbourX = node.x + 1;
int neighbourY = node.y + 1;
if (world.getTileType(neighbourX, neighbourY) != eTileType.NONWALKABLE)
{
neighbours.Add(GetNode(neighbourX, neighbourY, world.getTileType(neighbourX, neighbourY)));
}
}
return(neighbours);
}
