dualroids
Class Asteroid

java.lang.Object
  |
  +--dualroids.SpatialObject
        |
        +--dualroids.Asteroid

All Implemented Interfaces:

Serializable

public class Asteroid

extends SpatialObject

The representation of an asteroid in the model.

The Layout of the Asteroid Table

The length of the asteroid table is required to be a multiple of 7. The first large asteroid is at index 0. The second is at 7, etc.

When a large asteroid is at index i, its residual medium-sized asteroids are at indeces i + 1 and i + 4.

When a medium-sized asteroid is at index i, its residual small asteroids are at indeces i + 1 and i + 2.

A Note About Thread Safety

The setters of an Asteroid may be used from multiple threads. Also, the getters may be used from a single thread safely even when there are other thread using the setters. However, there may not be multiple threads calling getTransformedShape. It is designed to be used from a single thread only.

Also, that thread should not retain references to objects returned by getTransformedShape across the method calls. When the method is called the object it returned previously will no longer be valid.

See Also:

Serialized Form

Field Summary

private double	angle The rotation angle (in radians) of the spatial object at the moment indicated by timestamp.
private double	angularVelocity The angular velocity (radians per millisecond) of the asteroid.
private float[]	centers An array for storing the coordinates of the centers of the edges of this asteroid.
static float	COLOR_STEP The amount of time used for one outline color in an explosion.
static float	DEBRIS_LIFETIME The lifetime of asteroid debris.
static float	DEBRIS_VELOCITY_FACTOR Constant used when calculating the movement of asteroid debris.
private boolean	exploding A boolean indicating whether the asteroid is currently exploding (that is, whether debris is visible).
private int	hitsToExplosion The number of hits it takes to make this asteroid explode.
static int	LARGE Constant for indicating that the asteroid is large
static double	LARGE_EXPLOSION_EXTRA Constant used when modeling the extra energy released when a large asteroid explodes.
static int	MEDIUM Constant for indicating that the asteroid is medium-sized
static double	MEDIUM_EXPLOSION_EXTRA Constant used when modeling the extra energy released when a medium-sized asteroid explodes.
private int	outlineColor the outline color as an index to SpatialObject.COLOR_TABLE
private int	points
private int	size The size of the asteroid.
static int	SMALL Constant for indicating that the asteroid is small
private float[]	vertices An array for storing the coordinates of the vertices of this asteroid.
private boolean	visible A boolean indicating whether the asteroid is visible.

Fields inherited from class dualroids.SpatialObject

COLOR_TABLE, COLOR_TABLE_BLACK, COLOR_TABLE_GRAY_50, COLOR_TABLE_WHITE, geometry, locationX, locationY, timestamp, transform, velocityX, velocityY

Constructor Summary

Asteroid(double locationX, double locationY, double velocityX, double velocityY, long timestamp, int size)
Contructs a new asteroid.

Method Summary

static void	blowUpAsteroid(Asteroid[] asteroids, int index, double locationX, double locationY, long timestamp, boolean onServer) Makes an asteroid explode and initalizes the residual asteroids accordingly.
void	explode(long time) Tells the asteroid to explode.
void	explodeOnServer() Tells the asteroid to explode withou debris effects.
static void	generateResidualAsteroids(Asteroid[] asteroids) Generates residual asteroids in the array of asteroids passed as the argument.
double	getLocationX(long time) Returns the x coordinate of the location of the asteroid at time.
double	getLocationY(long time) Returns the y coordinate of the location of the asteroid at time.
Color	getOutlineColor() Returns the outline color of the asteroid.
int	getPoints() Returns the points awarded for blowing up this asteroid.
int	getSize() Indicates the size of the asteroid.
Shape	getTransformedShape(long time) Returns a properly transformed Shape representing the spatial object at time
boolean	isVisible() Indicates whether the asteroid is visible.
void	makeVisible() Makes the asteroid visible.
private void	readObject(ObjectInputStream in) Deserializes the asteroid on the client side.
boolean	registerHit() Registers a bullet hit to the asteroid and checks whether it explodes.
void	setLocationAndAngle(double locationX, double locationY, double angle, long timestamp) Sets the location and angle of this asteroid.
void	updateLocationAndAngle(long time) Updates the location and angle of this asteroid to the values corresponding to a moment in time given as the argument.
private void	writeObject(ObjectOutputStream out) Serializes the asteroid for sending to the clients.
void	writeToConnector(int thisIndex, ServerModelConnector connector) Writes the state of this asteroid to a ServerModelConnector.

Methods inherited from class dualroids.SpatialObject

moveToRangeX, moveToRangeY

Methods inherited from class java.lang.Object

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

Field Detail

SMALL

public static final int SMALL

Constant for indicating that the asteroid is small

MEDIUM

public static final int MEDIUM

Constant for indicating that the asteroid is medium-sized

LARGE

public static final int LARGE

Constant for indicating that the asteroid is large

LARGE_EXPLOSION_EXTRA

public static final double LARGE_EXPLOSION_EXTRA

Constant used when modeling the extra energy released when a large asteroid explodes.

MEDIUM_EXPLOSION_EXTRA

public static final double MEDIUM_EXPLOSION_EXTRA

Constant used when modeling the extra energy released when a medium-sized asteroid explodes.

DEBRIS_VELOCITY_FACTOR

public static final float DEBRIS_VELOCITY_FACTOR

Constant used when calculating the movement of asteroid debris.

DEBRIS_LIFETIME

public static final float DEBRIS_LIFETIME

The lifetime of asteroid debris.

COLOR_STEP

public static final float COLOR_STEP

The amount of time used for one outline color in an explosion.

outlineColor

private transient int outlineColor

the outline color as an index to SpatialObject.COLOR_TABLE

angularVelocity

private double angularVelocity

The angular velocity (radians per millisecond) of the asteroid.

size

private int size

The size of the asteroid. SMALL, MEDIUM or LARGE

visible

private boolean visible

A boolean indicating whether the asteroid is visible.

exploding

private boolean exploding

A boolean indicating whether the asteroid is currently exploding (that is, whether debris is visible).

angle

private double angle

The rotation angle (in radians) of the spatial object at the moment indicated by timestamp.

hitsToExplosion

private transient int hitsToExplosion

The number of hits it takes to make this asteroid explode.

vertices

private float[] vertices

An array for storing the coordinates of the vertices of this asteroid. The array is in the format accepted by AffineTransform: x0, y0, ... xn, yn.

points

private transient int points

centers

private transient float[] centers

An array for storing the coordinates of the centers of the edges of this asteroid. The array is in the format accepted by AffineTransform: x0, y0, ... xn, yn.

Constructor Detail

Asteroid

public Asteroid(double locationX,
                double locationY,
                double velocityX,
                double velocityY,
                long timestamp,
                int size)

Contructs a new asteroid. The geometry is created automatically. The angular velocity is chosen automatically. Large asteroids are visible initially. Other asteroids are invisible by default.

Parameters:

locationX - the x coordinate of the initial location

locationY - the y coordinate of the initial location

velocityX - the x component of the velocity

velocityY - the y component of the velocity

timestamp - the moment in game (server) time for which the location is valid

size - the size of the asteroid: SMALL, MEDIUM or LARGE

Method Detail

generateResidualAsteroids

public static void generateResidualAsteroids(Asteroid[] asteroids)

Generates residual asteroids in the array of asteroids passed as the argument.

Parameters:

asteroids - the asteroid table

blowUpAsteroid

public static void blowUpAsteroid(Asteroid[] asteroids,
                                  int index,
                                  double locationX,
                                  double locationY,
                                  long timestamp,
                                  boolean onServer)

Makes an asteroid explode and initalizes the residual asteroids accordingly.

Parameters:

asteroids - the asteroid table

index - the index of the asteroid to be blown up

locationX - the x coordinate of the asteroid at the time of the explosion

locationY - the y coordinate of the asteroid at the time of the explosion

timestamp - the point in time when the explosion happens

onServer - a boolean indicating whether this method is called from the server thread

getTransformedShape

public Shape getTransformedShape(long time)

Returns a properly transformed Shape representing the spatial object at time

Overrides:

getTransformedShape in class SpatialObject

Parameters:

time - the moment in game (server) time for which the representation is requested

Returns:

the Shape representation at time or null if the object isn't visible

setLocationAndAngle

public void setLocationAndAngle(double locationX,
                                double locationY,
                                double angle,
                                long timestamp)

Sets the location and angle of this asteroid. This method is supposed to be called from ClientModelController.

Parameters:

locationX - the x coordinate of the new location

locationY - the y coordinate of the new location

angle - the new angle

timestamp - the moment in game (server) time for which at which the other values were valid.

updateLocationAndAngle

public void updateLocationAndAngle(long time)

Updates the location and angle of this asteroid to the values corresponding to a moment in time given as the argument. The timestamp is updated accordingly.

Parameters:

time - the new timestamp

makeVisible

public final void makeVisible()

Makes the asteroid visible. used when a larger asteroid explodes. Be sure to call setLocationAndAngle first.

explode

public final void explode(long time)

Tells the asteroid to explode. It is up to the caller to make residual asteroids visible appropriately.

Parameters:

time - the point in time when the explosion starts

explodeOnServer

public void explodeOnServer()

Tells the asteroid to explode withou debris effects. It is up to the caller to make residual asteroids visible appropriately.

isVisible

public final boolean isVisible()

Indicates whether the asteroid is visible.

Returns:

a boolean indicating visibility

registerHit

public boolean registerHit()

Registers a bullet hit to the asteroid and checks whether it explodes.

Returns:

true if the hit causes the asteroid to explode and false otherwise

getSize

public final int getSize()

Indicates the size of the asteroid.

Returns:

the size of the asteroid

getOutlineColor

public final Color getOutlineColor()

Returns the outline color of the asteroid.

Returns:

the outline color of the asteroid

getLocationX

public final double getLocationX(long time)

Returns the x coordinate of the location of the asteroid at time.

Parameters:

time - the point in time for which the x coordinate is requested

Returns:

the x coordinate of the location of the asteroid at time

getLocationY

public final double getLocationY(long time)

Returns the y coordinate of the location of the asteroid at time.

Parameters:

time - the point in time for which the y coordinate is requested

Returns:

the y coordinate of the location of the asteroid at time

getPoints

public final int getPoints()

Returns the points awarded for blowing up this asteroid.

Returns:

the points awarded for blowing up this asteroid

writeToConnector

public final void writeToConnector(int thisIndex,
                                   ServerModelConnector connector)

Writes the state of this asteroid to a ServerModelConnector.

Parameters:

thisIndex - the index of this asteroid

connector - the target ServerModelConnector

writeObject

private void writeObject(ObjectOutputStream out)
                  throws IOException

Serializes the asteroid for sending to the clients.

Parameters:

out - the target stream

readObject

private void readObject(ObjectInputStream in)
                 throws IOException,
                        ClassNotFoundException

Deserializes the asteroid on the client side.

Parameters:

in - the source stream