package squidpony.squidgrid;
import squidpony.squidmath.*;
import java.util.ArrayList;
import java.util.Set;
/**
* A randomized flood-fill implementation that can be used for level generation (e.g. filling ponds and lakes), for
* gas propagation, or for all sorts of fluid-dynamics-on-the-cheap.
* Created by Tommy Ettinger on 4/7/2015.
*
* @see Splash An alternative implementation with a lighter API
*/
public class Spill {
/**
* The type of heuristic to use.
*/
public enum Measurement {
/**
* The distance it takes when only the four primary directions can be
* moved in. The default.
*/
MANHATTAN,
/**
* The distance it takes when diagonal movement costs the same as
* cardinal movement.
*/
CHEBYSHEV,
/**
* The distance it takes as the crow flies.
*/
EUCLIDEAN
}
/**
* This affects how distance is measured on diagonal directions vs. orthogonal directions. MANHATTAN should form a
* diamond shape on a featureless map, while CHEBYSHEV and EUCLIDEAN will form a square. If you only call
* Spill.start() once, you should strongly prefer MANHATTAN, even if the rest of the game uses another
* measurement, because CHEBYSHEV and EUCLIDEAN can produce odd, gap-filled flood-fills. Any case where you have
* too many gaps can be corrected to varying extent by calling start() more than once with slowly increasing values.
* Because start() will extend from the existing area of the Spill, holes are likely to be filled after a few calls,
* but if the last call to start() tries to fill too many more cells than the previous one, it can cause holes on
* the periphery of the Spill area.
*/
public Measurement measurement = Measurement.MANHATTAN;
/**
* Stores which parts of the map are accessible (with a value of true) and which are not (with a value of false,
* including both walls and unreachable sections of the map). Should not be changed unless the actual physical
* terrain has changed. You should call initialize() with a new map instead of changing this directly.
*/
public boolean[][] physicalMap;
/**
* The cells that are filled by the Spill when it reaches its volume or limits will be true; others will be false.
*/
public boolean[][] spillMap;
/**
* The list of points that the Spill will randomly fill, starting with what is passed to start(), in order of when
* they are reached.
*/
public ArrayList<Coord> spreadPattern;
/**
* Height of the map. Exciting stuff. Don't change this, instead call initialize().
*/
public int height;
/**
* Width of the map. Exciting stuff. Don't change this, instead call initialize().
*/
public int width;
/**
* The amount of cells filled by this Spill, which may be less than the volume passed to start() if the boundaries
* are reached on all sides and the Spill has no more room to fill.
*/
public int filled = 0;
private OrderedSet<Coord> fresh;
/**
* The RNG used to decide which one of multiple equally-short paths to take.
*/
public StatefulRNG rng;
/**
* The LightRNG used as a RandomnessSource for the RNG this object uses. Can have its state read and set.
*/
public LightRNG lrng;
private boolean initialized = false;
/**
* Construct a Spill without a level to actually scan. If you use this constructor, you must call an
* initialize() method before using this class.
*/
public Spill() {
lrng = new LightRNG();
rng = new StatefulRNG(lrng);
fresh = new OrderedSet<>();
}
/**
* Construct a Spill without a level to actually scan. This constructor allows you to specify an RNG, but the actual
* RandomnessSource the RNG that this object uses will not be identical to the one passed as random (64 bits will
* be requested from the passed RNG, and that will be used to seed this class' RNG).
*
* If you use this constructor, you must call an initialize() method before using this class.
*/
public Spill(RNG random) {
lrng = new LightRNG(random.nextLong());
rng = new StatefulRNG(lrng);
fresh = new OrderedSet<>();
}
/**
* Construct a Spill without a level to actually scan. This constructor allows you to specify a RandomnessSource
* in the form of a LightRNG, which will be referenced in this class (if the state of random changes because this
* object needed a random number, the state change will be reflected in the code that passed random to here).
*
* If you use this constructor, you must call an initialize() method before using this class.
*/
public Spill(LightRNG random) {
lrng = random;
rng = new StatefulRNG(lrng);
fresh = new OrderedSet<>();
}
/**
* Used to construct a Spill from the output of another.
* @param level
*/
public Spill(final boolean[][] level) {
lrng = new LightRNG();
rng = new StatefulRNG(lrng);
initialize(level);
}
/**
* Used to construct a Spill from the output of another, specifying a distance calculation.
* @param level
* @param measurement
*/
public Spill(final boolean[][] level, Measurement measurement) {
lrng = new LightRNG();
rng = new StatefulRNG(lrng);
this.measurement = measurement;
initialize(level);
}
/**
* Constructor meant to take a char[][] returned by DungeonBoneGen.generate(), or any other
* char[][] where '#' means a wall and anything else is a walkable tile. If you only have
* a map that uses box-drawing characters, use DungeonUtility.linesToHashes() to get a
* map that can be used here.
*
* @param level
*/
public Spill(final char[][] level) {
lrng = new LightRNG();
rng = new StatefulRNG(lrng);
initialize(level);
}
/**
* Constructor meant to take a char[][] returned by DungeonBoneGen.generate(), or any other
* char[][] where one char means a wall and anything else is a walkable tile. If you only have
* a map that uses box-drawing characters, use DungeonUtility.linesToHashes() to get a
* map that can be used here. You can specify the character used for walls.
*
* @param level
*/
public Spill(final char[][] level, char alternateWall) {
lrng = new LightRNG();
rng = new StatefulRNG(lrng);
initialize(level, alternateWall);
}
/**
* Constructor meant to take a char[][] returned by DungeonBoneGen.generate(), or any other
* char[][] where '#' means a wall and anything else is a walkable tile. If you only have
* a map that uses box-drawing characters, use DungeonUtility.linesToHashes() to get a
* map that can be used here. This constructor specifies a distance measurement.
*
* @param level
* @param measurement
*/
public Spill(final char[][] level, Measurement measurement) {
lrng = new LightRNG();
rng = new StatefulRNG(lrng);
this.measurement = measurement;
initialize(level);
}
/**
* Constructor meant to take a char[][] returned by DungeonBoneGen.generate(), or any other
* char[][] where '#' means a wall and anything else is a walkable tile. If you only have
* a map that uses box-drawing characters, use DungeonUtility.linesToHashes() to get a
* map that can be used here. This constructor specifies a distance measurement.
*
* This constructor allows you to specify an RNG, but the actual RandomnessSource the RNG that this object uses
* will not be identical to the one passed as random (64 bits will be requested from the passed RNG, and that will
* be used to seed this class' RNG).
*
* @param level
* @param measurement
*/
public Spill(final char[][] level, Measurement measurement, RNG random) {
lrng = new LightRNG(random.nextLong());
rng = new StatefulRNG(lrng);
this.measurement = measurement;
initialize(level);
}
/**
* Constructor meant to take a char[][] returned by DungeonBoneGen.generate(), or any other
* char[][] where '#' means a wall and anything else is a walkable tile. If you only have
* a map that uses box-drawing characters, use DungeonUtility.linesToHashes() to get a
* map that can be used here. This constructor specifies a distance measurement.
*
* This constructor allows you to specify a RandomnessSource in the form of a LightRNG, which will be referenced in
* this class (if the state of random changes because this object needed a random number, the state change will be
* reflected in the code that passed random to here).
* @param level
* @param measurement
*/
public Spill(final char[][] level, Measurement measurement, LightRNG random) {
lrng = random;
rng = new StatefulRNG(lrng);
this.measurement = measurement;
initialize(level);
}
/**
* Used to initialize or re-initialize a Spill that needs a new PhysicalMap because it either wasn't given
* one when it was constructed, or because the contents of the terrain have changed permanently (not if a
* creature moved; for that you pass the positions of creatures that block paths to scan() or findPath() ).
* @param level
* @return
*/
public Spill initialize(final boolean[][] level) {
fresh = new OrderedSet<>();
width = level.length;
height = level[0].length;
spillMap = new boolean[width][height];
physicalMap = new boolean[width][height];
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
spillMap[x][y] = level[x][y];
physicalMap[x][y] = level[x][y];
}
}
initialized = true;
return this;
}
/**
* Used to initialize or re-initialize a Spill that needs a new PhysicalMap because it either wasn't given
* one when it was constructed, or because the contents of the terrain have changed permanently (not if a
* creature moved; for that you pass the positions of creatures that block paths to scan() or findPath() ).
* @param level
* @return
*/
public Spill initialize(final char[][] level) {
fresh = new OrderedSet<>();
width = level.length;
height = level[0].length;
spillMap = new boolean[width][height];
physicalMap = new boolean[width][height];
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
spillMap[x][y] = false;
physicalMap[x][y] = level[x][y] != '#';
}
}
initialized = true;
return this;
}
/**
* Used to initialize or re-initialize a Spill that needs a new PhysicalMap because it either wasn't given
* one when it was constructed, or because the contents of the terrain have changed permanently (not if a
* creature moved; for that you pass the positions of creatures that block paths to scan() or findPath() ). This
* initialize() method allows you to specify an alternate wall char other than the default character, '#' .
* @param level
* @param alternateWall
* @return
*/
public Spill initialize(final char[][] level, char alternateWall) {
fresh = new OrderedSet<>();
width = level.length;
height = level[0].length;
spillMap = new boolean[width][height];
physicalMap = new boolean[width][height];
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
spillMap[x][y] = false;
physicalMap[x][y] = level[x][y] != alternateWall;
}
}
initialized = true;
return this;
}
/**
* Resets the spillMap to being empty.
*/
public void resetMap() {
if(!initialized) return;
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
spillMap[x][y] = false;
}
}
}
/**
* Resets this Spill to a state with an empty spillMap and an empty spreadPattern.
*/
public void reset() {
resetMap();
spreadPattern.clear();
fresh.clear();
}
/**
* Reverts a cell to an unfilled state (false in spillMap).
* @param x
* @param y
*/
public void resetCell(int x, int y) {
if(!initialized) return;
spillMap[x][y] = false;
}
/**
* Reverts a cell to an unfilled state (false in spillMap).
* @param pt
*/
public void resetCell(Coord pt) {
if(!initialized) return;
spillMap[pt.x][pt.y] = false;
}
protected void setFresh(int x, int y) {
if(!initialized) return;
fresh.add(Coord.get(x, y));
}
protected void setFresh(final Coord pt) {
if(!initialized) return;
fresh.add(pt);
}
/**
* Recalculate the spillMap and return the spreadPattern. The cell corresponding to entry will be true,
* the cells near that will be true if chosen at random from all passable cells adjacent to a
* filled (true) cell, and all other cells will be false. This takes a total number of cells to attempt
* to fill (the volume parameter), and will fill less if it has completely exhausted all passable cells.
* If the measurement this Spill uses is anything other than MANHATTAN, you can expect many gaps in the first
* filled area. Subsequent calls to start() with the same entry and a higher volume will expand the area
* of the Spill, and are likely to fill any gaps after a few subsequent calls. Increasing the volume slowly
* is the best way to ensure that gaps only exist on the very edge if you use a non-MANHATTAN measurement.
*
* @param entry The first cell to spread from, which should really be passable.
* @param volume The total number of cells to attempt to fill, which must be non-negative.
* @param impassable A Set of Position keys representing the locations of moving obstacles to a
* path that cannot be moved through; this can be null if there are no such obstacles.
* @return An ArrayList of Points that this will enter, in order starting with entry at index 0, until it
* reaches its volume or fills its boundaries completely.
*/
public ArrayList<Coord> start(Coord entry, int volume, Set<Coord> impassable) {
if(!initialized) return null;
if(impassable == null)
impassable = new OrderedSet<>();
if(!physicalMap[entry.x][entry.y] || impassable.contains(entry))
return null;
spreadPattern = new ArrayList<>(volume);
spillMap[entry.x][entry.y] = true;
Coord temp;
for(int x = 0; x < spillMap.length; x++)
{
for(int y = 0; y < spillMap[x].length; y++)
{
temp = Coord.get(x, y);
if(spillMap[x][y] && !impassable.contains(temp))
fresh.add(temp);
}
}
Direction[] dirs = (measurement == Measurement.MANHATTAN) ? Direction.CARDINALS : Direction.OUTWARDS;
while (!fresh.isEmpty() && spreadPattern.size() < volume) {
Coord cell = fresh.randomItem(rng);//toArray(new Coord[fresh.size()])[rng.nextInt(fresh.size())];
spreadPattern.add(cell);
spillMap[cell.x][cell.y] = true;
for (int d = 0; d < dirs.length; d++) {
Coord adj = cell.translate(dirs[d].deltaX, dirs[d].deltaY);
double h = heuristic(dirs[d]);
if (physicalMap[adj.x][adj.y] && !spillMap[adj.x][adj.y] && !impassable.contains(adj) && rng.nextDouble() <= 1.0 / h) {
setFresh(adj);
}
}
fresh.remove(cell);
}
filled = spreadPattern.size();
return spreadPattern;
}
private static final double root2 = Math.sqrt(2.0);
private double heuristic(Direction target) {
switch (measurement) {
case MANHATTAN:
case CHEBYSHEV:
return 1.0;
case EUCLIDEAN:
switch (target) {
case DOWN_LEFT:
case DOWN_RIGHT:
case UP_LEFT:
case UP_RIGHT:
return root2;
default:
return 1.0;
}
}
return 1.0;
}
}