burlap.domain.singleagent.blockdude

Class BlockDudeModel

java.lang.Object

burlap.domain.singleagent.blockdude.BlockDudeModel

All Implemented Interfaces:

FullStateModel, SampleStateModel

public class BlockDudeModel
extends java.lang.Object
implements FullStateModel

Author:

James MacGlashan.

Nested Class Summary

Nested classes/interfaces inherited from interface burlap.mdp.singleagent.model.statemodel.FullStateModel

FullStateModel.Helper

Field Summary

Fields

Modifier and Type	Field and Description
protected int	maxx
protected int	maxy

Constructor Summary

Constructors

Constructor and Description
BlockDudeModel(int maxx, int maxy)

Method Summary

Modifier and Type	Method and Description
protected BlockDudeCell	getBlockAt(BlockDudeState s, int x, int y) Finds a block object in the State located at the provided position and returns it
int	greatestHeightBelow(BlockDudeState s, int[][] map, int xWidth, int x, int maxY) Returns the maximum height of the world at the provided x coordinate that is <= the value maxY.
protected void	moveCarriedBlockToNewAgentPosition(BlockDudeState s, BlockDudeAgent agent, int ax, int ay, int nx, int ny) Moves a carried block to a new position of the agent
void	moveHorizontally(BlockDudeState s, int dx) Modifies state s to be the result of a horizontal movement.
void	moveUp(BlockDudeState s) Modifies state s to be the result of a vertical movement, that will result in the agent onto the platform adjacent to its current location in the direction the agent is facing, provided that there is room for the agent (and any block it's holding) to step onto it.
void	pickupBlock(BlockDudeState s) Modifies state s to be the result of the pick up action.
void	putdownBlock(BlockDudeState s) Modifies state s to put down the block the agent is holding.
State	sample(State s, Action a) Samples and returns a State from a state transition function.
java.util.List<StateTransitionProb>	stateTransitions(State s, Action a) Returns the set of possible transitions when Action is applied in State s.

Methods inherited from class java.lang.Object

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

Field Detail

maxx

protected int maxx

maxy

protected int maxy

Constructor Detail

BlockDudeModel

public BlockDudeModel(int maxx,
                      int maxy)

Method Detail

stateTransitions

public java.util.List<StateTransitionProb> stateTransitions(State s,
                                                            Action a)

Description copied from interface: FullStateModel

Returns the set of possible transitions when Action is applied in State s. The returned list only needs to include transitions that have non-zero probability of occurring.

Specified by:

stateTransitions in interface FullStateModel

Parameters:

s - the source state

a - the action to be applied in the source state

Returns:

the probability distribution of the state transition function specified as a list of StateTransitionProb objects.

sample

public State sample(State s,
                    Action a)

Description copied from interface: SampleStateModel

Samples and returns a State from a state transition function.

Specified by:

sample in interface SampleStateModel

Parameters:

s - the source state

a - the action to be executed in the source state

Returns:

a sample State

moveHorizontally

public void moveHorizontally(BlockDudeState s,
                             int dx)

Modifies state s to be the result of a horizontal movement. This method will also move any held blocks by the agent and cause the agent (and its held block) to fall if it walks off a cliff. The agent will not be able to move to an x position < 0 or >= the maximum x dimensionality

Parameters:

s - the state to modify

dx - the change in x direction; should only be +1 (east) or -1 (west).

moveUp

public void moveUp(BlockDudeState s)

Modifies state s to be the result of a vertical movement, that will result in the agent onto the platform adjacent to its current location in the direction the agent is facing, provided that there is room for the agent (and any block it's holding) to step onto it.

Parameters:

s - the state to modify.

pickupBlock

public void pickupBlock(BlockDudeState s)

Modifies state s to be the result of the pick up action. If no block that is clear (i.e., no block on top of it) is in front of the agent, then a block is not picked up.

Parameters:

s - the state to modify.

putdownBlock

public void putdownBlock(BlockDudeState s)

Modifies state s to put down the block the agent is holding. If the agent is not holding a block or there is not a clear place to put the block, then the action does nothing.

Parameters:

s - the state to modify

moveCarriedBlockToNewAgentPosition

protected void moveCarriedBlockToNewAgentPosition(BlockDudeState s,
                                                  BlockDudeAgent agent,
                                                  int ax,
                                                  int ay,
                                                  int nx,
                                                  int ny)

Moves a carried block to a new position of the agent

Parameters:

s - the state to modify

agent - the agent

ax - the previous x position of the agent

ay - the previous y position of the agent

nx - the new x position of the *agent*

ny - the new y position of the *agent*

getBlockAt

protected BlockDudeCell getBlockAt(BlockDudeState s,
                                   int x,
                                   int y)

Finds a block object in the State located at the provided position and returns it

Parameters:

s - the state to check

x - the x position

y - the y position

Returns:

the BlockDudeCell for the corresponding block object in the state at the given position or null if one does not exist.

greatestHeightBelow

public int greatestHeightBelow(BlockDudeState s,
                               int[][] map,
                               int xWidth,
                               int x,
                               int maxY)

Returns the maximum height of the world at the provided x coordinate that is <= the value maxY. The height is based on either the highest brick at x and y <= maxY, or the highest block at x and y <= maxY.

Parameters:

s - the state to search

map - the brick map

xWidth - the maximum x dimensionality of the world

x - the x position to search

maxY - the y position under which the highest point is searched

Returns:

the maximum height or zero if there are no bricks or blocks at x, y <= maxY.