dev.roanh.convexmerger.game

Class PlayfieldGenerator

java.lang.Object

dev.roanh.convexmerger.game.PlayfieldGenerator

public class PlayfieldGenerator
extends java.lang.Object

Generator to generate a playfield of randomly placed convex objects on a rectangular plane. The plane has size 0~1600 on the x-axis and 0~900 on the y-axis. Generated playfields will never contain overlapping objects and objects will be distributed evenly. Each of the convex objects will be defined by 3 to 4 points and all convex objects will have roughly the same area.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	PlayfieldGenerator.GeneratorProgressListener Listener interface for classes that want to informed of playfield generation progress.

Field Summary

Fields

Modifier and Type	Field and Description
private static int	AREA_DIV_NUM The area of the base triangle is divided this to set the minimum required area for an object
private float	coverage Desired playfield coverage.
private int	coverageNum Coverage value in range 0-255.
private static double	DIAGONAL_LENGTH_RATIO Ratio between the length of both diagonals in an object (recommended between 1.0 and 1.8).
private PlayfieldGenerator.GeneratorProgressListener	listener Listener to notify of generation progress.
private java.util.Random	random Local random instance to use the generate the playfield.
private int	rangeMax Maximum object size.
private int	rangeMin Minimum object size.
private float	scale Object scaling factor.
private int	scaleNum Scaling value in range 0-255.
private long	seed The random seed for this playfield generator.

Constructor Summary

Constructors

Constructor and Description
PlayfieldGenerator() Constructs a new playfield generator with a random seed, range of 0-100, coverage of 0.2745 and scale of 0.78.
PlayfieldGenerator(java.lang.String seed) Constructs a new playfield generate with the given seed.

Method Summary

Modifier and Type	Method and Description
private double	areaObject(int rMax) Function to determine the approximate minimum area for an object
java.util.List<ConvexObject>	generatePlayfield() Generates a new game playfield with convex objects made up of 3 to 4 points.
int	getCoverage() Gets the coverage number for this generator.
int	getRangeMax() Gets the minimum size range for this generator.
int	getRangeMin() Gets the maximum size range for this generator.
int	getScaling() Gets the scaling number for this generator.
java.lang.String	getSeed() Gets the seed that describes this random generator.
private static boolean	hasSeedMarker(long high) Checks if the given high order bits of a seed represent a valid game seed.
private void	init(long seed, int rangeMin, int rangeMax, int coverageNum, int scaleNum) Initialises the internal generator state.
static boolean	isValidSeed(java.lang.String seed) Tests if the given seed is a valid game seed.
void	setCoverage(int coverage) Sets the minimum total area of the whole playfield that should be covered by convex objects before scaling.
void	setProgressListener(PlayfieldGenerator.GeneratorProgressListener listener) Sets the listener to notify of playfield generation progress.
void	setRange(int min, int max) Sets the size range of generated objects.
void	setScaling(int scaling) Sets the factor by with which to scale all objects after generation.
void	setSeed(java.lang.String seed) Sets the seed of this generator to the given seed.

Methods inherited from class java.lang.Object

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

Field Detail

AREA_DIV_NUM

private static final int AREA_DIV_NUM

The area of the base triangle is divided this to set the minimum required area for an object

See Also:

Constant Field Values

DIAGONAL_LENGTH_RATIO

private static final double DIAGONAL_LENGTH_RATIO

Ratio between the length of both diagonals in an object (recommended between 1.0 and 1.8).

See Also:

Constant Field Values

random

private java.util.Random random

Local random instance to use the generate the playfield.

seed

private long seed

The random seed for this playfield generator.

rangeMin

private int rangeMin

Minimum object size.

rangeMax

private int rangeMax

Maximum object size.

coverageNum

private int coverageNum

Coverage value in range 0-255.

See Also:

coverage

scaleNum

private int scaleNum

Scaling value in range 0-255.

See Also:

scale

coverage

private float coverage

Desired playfield coverage.

scale

private float scale

Object scaling factor.

listener

private PlayfieldGenerator.GeneratorProgressListener listener

Listener to notify of generation progress.

Constructor Detail

PlayfieldGenerator

public PlayfieldGenerator()

Constructs a new playfield generator with a random seed, range of 0-100, coverage of 0.2745 and scale of 0.78.

PlayfieldGenerator

public PlayfieldGenerator(java.lang.String seed)
                   throws java.lang.IllegalArgumentException

Constructs a new playfield generate with the given seed.

Parameters:

seed - The seed to use.

Throws:

java.lang.IllegalArgumentException - When the given seed is invalid

Method Detail

setProgressListener

public void setProgressListener(PlayfieldGenerator.GeneratorProgressListener listener)

Sets the listener to notify of playfield generation progress.

Parameters:

listener - The listener to register.

See Also:

PlayfieldGenerator.GeneratorProgressListener

init

private void init(long seed,
                  int rangeMin,
                  int rangeMax,
                  int coverageNum,
                  int scaleNum)

Initialises the internal generator state.

Parameters:

seed - Random number generator seed.

rangeMin - Minimum object size.

rangeMax - Maximum object size.

coverageNum - Playfield coverage.

scaleNum - Object scaling.

setSeed

public void setSeed(java.lang.String seed)
             throws java.lang.IllegalArgumentException

Sets the seed of this generator to the given seed.

Parameters:

seed - The new seed.

Throws:

java.lang.IllegalArgumentException - When the seed is invalid.

See Also:

isValidSeed(String)

getRangeMin

public int getRangeMin()

Gets the maximum size range for this generator.

Returns:

The maximum object size range.

See Also:

setRange(int, int)

getRangeMax

public int getRangeMax()

Gets the minimum size range for this generator.

Returns:

The minimum object size range.

See Also:

setRange(int, int)

getCoverage

public int getCoverage()

Gets the coverage number for this generator.

Returns:

The coverage number for this generator.

See Also:

setCoverage(int)

getScaling

public int getScaling()

Gets the scaling number for this generator.

Returns:

The scaling number.

See Also:

setScaling(int)

getSeed

public java.lang.String getSeed()

Gets the seed that describes this random generator.

Returns:

The seed for this random generator.

setRange

public void setRange(int min,
                     int max)
              throws java.lang.IllegalArgumentException

Sets the size range of generated objects.

Parameters:

min - The minimum size range for convex objects (at least 0).

max - The maximum size range for convex objects. Small values for this parameter may resulting in generating the playfield taking longer, values larger than 20 are recommended (at most 255).

Throws:

java.lang.IllegalArgumentException - When the given range is invalid.

setCoverage

public void setCoverage(int coverage)
                 throws java.lang.IllegalArgumentException

Sets the minimum total area of the whole playfield that should be covered by convex objects before scaling. High values for this parameter may result in extremely long or even infinite generation times. It is recommended to use a value such that coverage / 255 is 0.5 or less (so at most 127).

Parameters:

coverage - The new coverage value.

Throws:

java.lang.IllegalArgumentException - When the given value is out of range (0 - 255).

setScaling

public void setScaling(int scaling)
                throws java.lang.IllegalArgumentException

Sets the factor by with which to scale all objects after generation.

Parameters:

scaling - The scaling factor, computed as scaling / 255.

Throws:

java.lang.IllegalArgumentException - When the given value is out of range (0 - 255).

areaObject

private double areaObject(int rMax)

Function to determine the approximate minimum area for an object

Parameters:

rMax - The maximum range for an object.

Returns:

The computed minimum area for an object.

generatePlayfield

public java.util.List<ConvexObject> generatePlayfield()

Generates a new game playfield with convex objects made up of 3 to 4 points. The objects will have coordinates within 0~ on the x-axis and within 0~ on the y-axis. In addition they will be evenly distributed across this plane. Objects will also not overlap and all have approximately the same area and conform to the set parameters.

Returns:

A list of convex objects representing the generated playfield.

isValidSeed

public static boolean isValidSeed(java.lang.String seed)

Tests if the given seed is a valid game seed.

Parameters:

seed - The seed to test.

Returns:

True if the seed is a valid game seed.

hasSeedMarker

private static boolean hasSeedMarker(long high)

Checks if the given high order bits of a seed represent a valid game seed.

Parameters:

high - The high order seed bits.

Returns:

True if the high order bits represent a valid seed.