Java
Eu usei uma abordagem baseada em diagramas recursivos de Voronoi. As saídas não parecem muito realistas, mas acho que estão bem.
Aqui estão alguns exemplos de imagens (redimensionadas para 250x250 para não preencher a tela inteira):
0:
1:
Mais detalhes sobre o algoritmo:
Todas as imagens nesta seção estão usando a mesma semente.
O algoritmo começa gerando um diagrama de Voronoi com 5 pontos:
Se olharmos para as imagens originais no desafio, podemos ver que as linhas não são todas retas assim, então pesamos a distância por um valor aleatório, com base no ângulo do ponto, além disso, ângulos mais próximos fornecem valores mais próximos :
Agora, desenhamos recursivamente esses tipos de diagramas de Voronoi dentro de cada região, com linhas mais finas e transparentes, e removemos o fundo, com uma profundidade de recursão máxima de 3, e obtemos:
Agora, basta adicionar o fundo marrom claro e pronto!
Código:
O código consiste em três classes Main.java, VoronoiPoint.javae Vector.java:
Main.java:
import java.awt.Desktop;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Random;
import javax.imageio.ImageIO;
public class Main {
public static int WIDTH = 500;
public static int HEIGHT = 500;
public static int RECURSION_LEVELS = 3;
public static int AMOUNT_OF_POINTS = 5;
public static int ROTATION_RESOLUTION = 600;
public static int ROTATION_SMOOTHNESS = 10;
public static int BACKGROUND = 0xFFE0CBAD;
public static Random RAND;
public static void main(String[] args) {
int seed = new Random().nextInt(65536);
if (args.length == 1) {
System.out.println(Arrays.toString(args));
seed = Integer.parseInt(args[0]);
} else {
System.out.println("Generated seed: " + seed);
}
RAND = new Random(seed);
ArrayList<Vector> points = new ArrayList<Vector>();
for (int x = 0; x < WIDTH; x++) {
for (int y = 0; y < HEIGHT; y++) {
points.add(new Vector(x, y));
}
}
BufferedImage soil = generateSoil(WIDTH, HEIGHT, seed, points, AMOUNT_OF_POINTS, RECURSION_LEVELS);
BufferedImage background = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_ARGB);
for (int x = 0; x < background.getWidth(); x++) {
for (int y = 0; y < background.getHeight(); y++) {
background.setRGB(x, y, BACKGROUND ^ (RAND.nextInt(10) * 0x010101));
}
}
Graphics g = background.getGraphics();
g.drawImage(soil, 0, 0, null);
g.dispose();
String fileName = "soil";
File output = new File(fileName + ".png");
for (int i = 0; output.exists(); i++) {
output = new File(fileName + i + ".png");
}
try {
ImageIO.write(background, "png", output);
Desktop.getDesktop().open(output);
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("Done. Saved as " + output);
}
private static BufferedImage generateSoil(int width, int height, int seed, ArrayList<Vector> drawPoints,
int amountOfPoints, int recursionLevel) {
BufferedImage result = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
ArrayList<VoronoiPoint> points = new ArrayList<VoronoiPoint>();
for (int i = 0; i < amountOfPoints; i++) {
points.add(new VoronoiPoint(drawPoints.get(RAND.nextInt(drawPoints.size()))));
}
HashMap<Integer, ArrayList<Vector>> pointMaps = new HashMap<Integer, ArrayList<Vector>>();
for (VoronoiPoint point : points) {
pointMaps.put(point.hashCode(), new ArrayList<Vector>());
}
System.out.println(pointMaps);
System.out.println(points);
for (Vector v : drawPoints) {
VoronoiPoint closest = null;
VoronoiPoint secondClosest = null;
for (VoronoiPoint point : points) {
double distance = point.getMultiplicativeDistanceTo(v);
if (closest == null || distance < closest.getMultiplicativeDistanceTo(v)) {
secondClosest = closest;
closest = point;
} else if (secondClosest == null || distance < secondClosest.getMultiplicativeDistanceTo(v)) {
secondClosest = point;
}
}
int col = 0;
if (Math.abs(closest.getMultiplicativeDistanceTo(v)
- secondClosest.getMultiplicativeDistanceTo(v)) < (recursionLevel * 5 / RECURSION_LEVELS)) {
col = 0x01000000 * (recursionLevel * 255 / RECURSION_LEVELS);
} else {
pointMaps.get(closest.hashCode()).add(v);
}
result.setRGB((int) v.getX(), (int) v.getY(), col);
}
Graphics g = result.getGraphics();
if (recursionLevel > 0) {
for (ArrayList<Vector> pixels : pointMaps.values()) {
if (pixels.size() > 10) {
BufferedImage img = generateSoil(width, height, seed, pixels, amountOfPoints,
recursionLevel - 1);
g.drawImage(img, 0, 0, null);
}
}
}
g.dispose();
return result;
}
public static int modInts(int a, int b) {
return (int) mod(a, b);
}
public static double mod(double a, double b) {
a = a % b;
while (a < 0)
a += b;
return a;
}
}
VoronoiPoint.java:
public class VoronoiPoint {
private Vector pos;
private double[] distances;
public VoronoiPoint(Vector pos) {
this.pos = pos;
distances = new double[Main.ROTATION_RESOLUTION];
for (int i = 0; i < distances.length; i++)
distances[i] = Main.RAND.nextFloat() / 2 + 0.51;
for (int iter = 0; iter < Main.ROTATION_SMOOTHNESS; iter++) {
for (int i = 0; i < distances.length; i++) {
distances[i] = (distances[Main.modInts(i - Main.RAND.nextInt(4) - 2, distances.length)] + distances[i]
+ distances[Main.modInts(i + Main.RAND.nextInt(4) - 2, distances.length)]) / 3;
}
}
}
public Vector getPos() {
return pos;
}
public double getRotationFromAngle(double radians) {
return distances[(int) (Main.mod(Math.toDegrees(radians) / 360, 1) * distances.length)];
}
public double getRotationFromVector(Vector vec) {
return getRotationFromAngle(Math.atan2(pos.getY() - vec.getY(), -(pos.getX() - vec.getX())));
}
public double getMultiplicativeDistanceTo(Vector other) {
return pos.getLengthTo(other) * getRotationFromVector(other);
}
public String toString() {
return "VoronoiPoint(pos=[" + pos.getX() + ", " + pos.getY() + "])";
}
public int hashCode() {
return distances.hashCode() ^ pos.hashCode();
}
}
Vector.java: (Esta classe é copiada de um dos meus outros projetos, portanto, contém algum código desnecessário)
package com.loovjo.soil;
import java.util.ArrayList;
import java.util.Random;
public class Vector {
private static final float SMALL = 1f / Float.MAX_EXPONENT * 100;
private float x, y;
public Vector(float x, float y) {
this.setX(x);
this.setY(y);
}
public Vector(int x, int y) {
this.setX(x);
this.setY(y);
}
public Vector(double x, double y) {
this.setX((float) x);
this.setY((float) y);
}
public float getY() {
return y;
}
public void setY(float y) {
this.y = y;
}
public float getX() {
return x;
}
public void setX(float x) {
this.x = x;
}
/*
* Gets the length ^ 2 This is faster than getting the length.
*/
public float getLengthToSqrd(float x, float y) {
return (float) ((this.x - x) * (this.x - x) + (this.y - y) * (this.y - y));
}
public float getLengthToSqrd(Vector v) {
return getLengthToSqrd(v.x, v.y);
}
public float getLengthSqrd() {
return getLengthToSqrd(0, 0);
}
public float getLengthTo(float x, float y) {
return (float) Math.sqrt(getLengthToSqrd(x, y));
}
public float getLengthTo(Vector v) {
return getLengthTo(v.x, v.y);
}
public float getLength() {
return getLengthTo(0, 0);
}
public Vector setLength(float setLength) {
float length = getLength();
x *= setLength / length;
y *= setLength / length;
return this;
}
public float getFastLengthTo(float x, float y) {
return getFastLengthTo(new Vector(x, y));
}
public float getFastLengthTo(Vector v) {
float taxiLength = getTaxiCabLengthTo(v);
float chebyDist = getChebyshevDistanceTo(v);
return Float.min(taxiLength * 0.7f, chebyDist);
}
public float getFastLength() {
return getLengthTo(0, 0);
}
public Vector setFastLength(float setLength) {
float length = getFastLength();
x *= setLength / length;
y *= setLength / length;
return this;
}
public float getTaxiCabLengthTo(float x, float y) {
return Math.abs(this.x - x) + Math.abs(this.y - y);
}
public float getTaxiCabLengthTo(Vector v) {
return getTaxiCabLengthTo(v.x, v.y);
}
public float getTaxiCabLength() {
return getTaxiCabLengthTo(0, 0);
}
public Vector setTaxiCabLength(float setLength) {
float length = getTaxiCabLength();
x *= setLength / length;
y *= setLength / length;
return this;
}
public Vector absIfBoth() {
if (x < 0 && y < 0)
return new Vector(-x, -y);
return this;
}
public Vector abs() {
return new Vector(x < 0 ? -x : x, y < 0 ? -y : y);
}
public float getChebyshevDistanceTo(float x, float y) {
return Math.max(Math.abs(this.x - x), Math.abs(this.y - y));
}
public float getChebyshevDistanceTo(Vector v) {
return getChebyshevDistanceTo(v.x, v.y);
}
public float getChebyshevDistance() {
return getChebyshevDistanceTo(0, 0);
}
public Vector setChebyshevLength(float setLength) {
float length = getChebyshevDistance();
x *= setLength / length;
y *= setLength / length;
return this;
}
public Vector sub(Vector v) {
return new Vector(this.x - v.getX(), this.y - v.getY());
}
public Vector add(Vector v) {
return new Vector(this.x + v.getX(), this.y + v.getY());
}
public Vector mul(Vector v) {
return new Vector(this.x * v.getX(), this.y * v.getY());
}
public Vector mul(float f) {
return mul(new Vector(f, f));
}
public Vector div(Vector v) {
return new Vector(this.x / v.getX(), this.y / v.getY());
}
public Vector div(float f) {
return div(new Vector(f, f));
}
public Vector mod(Vector v) {
return new Vector(this.x % v.getX(), this.y % v.getY());
}
public Vector mod(int a, int b) {
return mod(new Vector(a, b));
}
public Vector mod(int a) {
return mod(a, a);
}
public String toString() {
return "Vector(" + getX() + ", " + getY() + ")";
}
/*
* Returns a list with vectors, starting with this, ending with to, and each
* one having length between them
*/
public ArrayList<Vector> loop(Vector to, float length) {
Vector delta = this.sub(to);
float l = delta.getLength();
ArrayList<Vector> loops = new ArrayList<Vector>();
for (float i = length; i < l; i += length) {
delta.setLength(i);
loops.add(delta.add(to));
}
loops.add(this);
return loops;
}
public boolean intersects(Vector pos, Vector size) {
pos.sub(this);
if (pos.getX() < getX())
return false;
if (pos.getY() < getY())
return false;
return true;
}
public Vector copy() {
return new Vector(x, y);
}
public void distort(float d) {
x += Math.random() * d - d / 2;
y += Math.random() * d - d / 2;
}
@Override
public boolean equals(Object o) {
if (o instanceof Vector) {
Vector v = (Vector) o;
return getLengthToSquared(v) < SMALL * SMALL;
}
return false;
}
private float getLengthToSquared(Vector v) {
return sub(v).getLengthSquared();
}
private float getLengthSquared() {
return x * x + y * y;
}
public boolean kindaEquals(Vector o, int i) {
if (o.x + i < x)
return false;
if (o.x - i > x)
return false;
if (o.y + i < y)
return false;
if (o.y - i > y)
return false;
return true;
}
/*
* Gets the direction, from 0 to 8.
*/
public int getDirection() {
return (getDirectionInDegrees()) / (360 / 8);
}
/*
* Gets the direction in degrees.
*/
public int getDirectionInDegrees() {
return (int) positize((float) Math.toDegrees(Math.atan2(x, -y)), 360f);
}
private float positize(float f, float base) {
while (f < 0)
f += base;
return f;
}
// 0 = north,
// 1 = northeast,
// 2 = east,
// 3 = southeast,
// 4 = south,
// 5 = southwest,
// 6 = west,
// 7 = northwest
public Vector moveInDir(int d) {
d = d % 8;
d = (int) positize(d, 8);
if (d == 0)
return this.add(new Vector(0, -1));
if (d == 1)
return this.add(new Vector(1, -1));
if (d == 2)
return this.add(new Vector(1, 0));
if (d == 3)
return this.add(new Vector(1, 1));
if (d == 4)
return this.add(new Vector(0, 1));
if (d == 5)
return this.add(new Vector(-1, 1));
if (d == 6)
return this.add(new Vector(-1, 0));
if (d == 7)
return this.add(new Vector(-1, -1));
return this;
}
/*
* Gets the angle in degrees to o.
*/
public float getRotationTo(Vector o) {
float d = (float) Math.toDegrees((Math.atan2(y - o.y, -(x - o.x))));
while (d < 0)
d += 360;
while (d > 360)
d -= 360;
return d;
}
public float getRotation() {
return getRotationTo(new Vector(0, 0));
}
/*
* In degrees
*/
public Vector rotate(double n) {
n = Math.toRadians(n);
float rx = (float) ((this.x * Math.cos(n)) - (this.y * Math.sin(n)));
float ry = (float) ((this.x * Math.sin(n)) + (this.y * Math.cos(n)));
return new Vector(rx, ry);
}
public int hashCode() {
int xx = (int) x ^ (int)(x * Integer.MAX_VALUE);
int yy = (int) y ^ (int)(y * Integer.MAX_VALUE);
return new Random(12665 * xx).nextInt() ^ new Random(5349 * yy).nextInt() + new Random((30513 * xx) ^ (19972 * yy)).nextInt();
}
public boolean isPositive() {
return x >= 0 && y >= 0;
}
public Vector clone() {
return new Vector(x, y);
}
}
Mas não quero compilar um monte de classes Java!
Aqui está um arquivo JAR que você pode executar para gerar essas imagens você mesmo. Corra como java -jar Soil.jar number, onde numberestá a semente (pode ser qualquer coisa até 2 31 -1), ou corra como java -jar Soil.jar, e escolhe uma semente por si só. Haverá alguma saída de depuração.
