path
Class GridNode

java.lang.Object
  path.AStarNode
      path.GridNode

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable

public class GridNode
extends AStarNode

Node that represents a square in the walkable area grid. This node is then used for A* path finding.

Author:

Frank Bruns

See Also:

Serialized Form

Constructor Summary

GridNode(double x, double y, int width, int height)
Creates a new grid node with the specified parameters

Method Summary

void	addNeighbor(GridNode node) Adds a neighbour to the list of neighbours of this grid node
boolean	containsPoint(double x, double y) Checks, if the specified coordinates lay in this grid node's bounds
float	getCost(AStarNode node) Gets the cost between this node and the specified adjacent (aka "neighbor" or "child") node.
float	getEstimatedCost(AStarNode node) Gets the estimated cost between this node and the specified node.
int	getHeight() Returns the height of the grid node
double	getMidX() Returns the x coordinate of the center point of the grid node
double	getMidY() Returns the y coordinate of the center point of the grid node
java.util.List<GridNode>	getNeighbors() Gets the children (aka "neighbors" or "adjacent nodes") of this node.
int	getWidth() Returns the width of the grid node
double	getX() Returns the x coordinate of the grid node
double	getY() Returns the y coordinate of the grid node
boolean	isNeighbor(GridNode node) Determines whether the grid node is a neighbour of the specified node.
boolean	isWalkable() Determines whether the grid node is walkable
void	setWalkable(boolean walkable) Sets the walkable status for the grid node

Methods inherited from class path.AStarNode

compareTo, getCost, sign

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GridNode

public GridNode(double x,
                double y,
                int width,
                int height)

Creates a new grid node with the specified parameters

Parameters:

x - x coordinate of the grid node

y - y coordinate of the grid node

width - width of the grid node

height - height of the grid node

Method Detail

setWalkable

public void setWalkable(boolean walkable)

Sets the walkable status for the grid node

Parameters:

walkable - set walkable? --> true=yes, false=no

getMidX

public double getMidX()

Returns the x coordinate of the center point of the grid node

Returns:

center point's x coordinate

getMidY

public double getMidY()

Returns the y coordinate of the center point of the grid node

Returns:

center point's y coordinate

containsPoint

public boolean containsPoint(double x,
                             double y)

Checks, if the specified coordinates lay in this grid node's bounds

Parameters:

x - x coordinates

y - y coordinates

Returns:

are coordinates within grid node's bounds? --> true=yes, false=no

isNeighbor

public boolean isNeighbor(GridNode node)

Determines whether the grid node is a neighbour of the specified node.

Parameters:

node - node to check, if naighbour

Returns:

is neighbour? --> true=yes, false=no

getHeight

public int getHeight()

Returns the height of the grid node

Returns:

height of the grid node

getWidth

public int getWidth()

Returns the width of the grid node

Returns:

width of the grid node

getX

public double getX()

Returns the x coordinate of the grid node

Returns:

x coordinate of the grid node

getY

public double getY()

Returns the y coordinate of the grid node

Returns:

y coordinate of the grid node

isWalkable

public boolean isWalkable()

Determines whether the grid node is walkable

Returns:

is grid node walkable? --> true=yes, false=no

addNeighbor

public void addNeighbor(GridNode node)

Adds a neighbour to the list of neighbours of this grid node

Parameters:

node - grid node neighbour node to add

getCost

public float getCost(AStarNode node)

Description copied from class: AStarNode

Gets the cost between this node and the specified adjacent (aka "neighbor" or "child") node.

Specified by:

getCost in class AStarNode

getEstimatedCost

public float getEstimatedCost(AStarNode node)

Description copied from class: AStarNode

Gets the estimated cost between this node and the specified node. The estimated cost should never exceed the true cost. The better the estimate, the more effecient the search.

Specified by:

getEstimatedCost in class AStarNode

getNeighbors

public java.util.List<GridNode> getNeighbors()

Description copied from class: AStarNode

Gets the children (aka "neighbors" or "adjacent nodes") of this node.

Specified by:

getNeighbors in class AStarNode