Add gaussian methods to UtilMath

Plugins/Mineplex.Core.Common.Base/src/mineplex/core/common/util/UtilMath.java

@@ -6,6 +6,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
 import java.util.Random;
+import java.util.concurrent.ThreadLocalRandom;
 
 import org.bukkit.Location;
 import org.bukkit.entity.Entity;
@@ -13,6 +14,8 @@ import org.bukkit.util.Vector;
 
 public class UtilMath
 {
+	public static final double TAU = Math.PI * 2D;
+
 	public static double trim(int degree, double d)
 	{
 		String format = "#.#";
@@ -332,4 +335,119 @@ public class UtilMath
 		
 		return min;
 	}
+
+	/**
+	 * Creates an array of points, arranged in a circle normal to a vector.
+	 *
+	 * @param center The center of the circle.
+	 * @param normal A vector normal to the circle.
+	 * @param radius The radius of the circle.
+	 * @param points How many points to make up the circle.
+	 *
+	 * @return An array of points of the form <code>double[point #][x=0, y=1, z=3]</code>.
+	 */
+	public static double[][] normalCircle(Location center, Vector normal, double radius, int points)
+	{
+		return normalCircle(center.toVector(), normal, radius, points);
+	}
+
+	/**
+	 * Creates an array of points, arranged in a circle normal to a vector.
+	 *
+	 * @param center The center of the circle.
+	 * @param normal A vector normal to the circle.
+	 * @param radius The radius of the circle.
+	 * @param points How many points to make up the circle.
+	 *
+	 * @return An array of points of the form <code>double[point #][x=0, y=1, z=3]</code>.
+	 */
+	public static double[][] normalCircle(Vector center, Vector normal, double radius, int points)
+	{
+		Vector n = normal.clone().normalize();
+		Vector a = n.clone().add(new Vector(1, 1, 1)).crossProduct(n).normalize();
+		Vector b = n.getCrossProduct(a).normalize();
+
+		double[][] data = new double[points][3];
+
+		double interval = TAU / points;
+		double theta = 0;
+
+		for (int i = 0; i < points; i++)
+		{
+			data[i][0] = center.getX() + (radius * ((Math.cos(theta) * a.getX()) + (Math.sin(theta) * b.getX())));
+			data[i][1] = center.getY() + (radius * ((Math.cos(theta) * a.getY()) + (Math.sin(theta) * b.getY())));
+			data[i][2] = center.getZ() + (radius * ((Math.cos(theta) * a.getZ()) + (Math.sin(theta) * b.getZ())));
+			theta += interval;
+		}
+
+		return data;
+	}
+
+	/**
+	 * Slightly randomize a location with a standard deviation of one.
+	 *
+	 * @param location The location to randomize.
+	 *
+	 * @return The original location, now gaussian-randomized.
+	 */
+	public static Location gauss(Location location)
+	{
+		return gauss(location, 1, 1, 1);
+	}
+
+	/**
+	 * Slightly randomize a vector with a standard deviation of one.
+	 *
+	 * @param vector The location to randomize.
+	 *
+	 * @return The randomized vector, now gaussian-randomized.
+	 */
+	public static Vector gauss(Vector vector)
+	{
+		return gauss(vector, 1, 1, 1);
+	}
+
+	/**
+	 * Slightly randomize a location with a standard deviation of one. <br>
+	 *
+	 * <b>This method only accepts positive values for all of its arguments.</b> <br>
+	 *
+	 * A good parameter set for small offsets is (loc, 10, 10, 10).
+	 *
+	 * @param location The location to randomize.
+	 * @param x A granularity control for the x-axis, higher numbers = less randomness
+	 * @param y A granularity control for the y-axis, higher numbers = less randomness
+	 * @param z A granularity control for the z-axis, higher numbers = less randomness
+	 *
+	 * @return The original location, now gaussian-randomized
+	 */
+	public static Location gauss(Location location, double x, double y, double z)
+	{
+		return location.clone().add(
+				x <= 0 ? 0 : (ThreadLocalRandom.current().nextGaussian() / x),
+				y <= 0 ? 0 : (ThreadLocalRandom.current().nextGaussian() / y),
+				z <= 0 ? 0 : (ThreadLocalRandom.current().nextGaussian() / z));
+	}
+
+	/**
+	 * Slightly randomize a vector with a standard deviation of one. <br>
+	 *
+	 * <b>This method only accepts positive values for all of its arguments.</b> <br>
+	 *
+	 * A good parameter set for small offsets is (loc, 10, 10, 10).
+	 *
+	 * @param vector The location to randomize.
+	 * @param x A granularity control for the x-axis, higher numbers = less randomness
+	 * @param y A granularity control for the y-axis, higher numbers = less randomness
+	 * @param z A granularity control for the z-axis, higher numbers = less randomness
+	 *
+	 * @return The randomized vector, now gaussian-randomized
+	 */
+	public static Vector gauss(Vector vector, double x, double y, double z)
+	{
+		return vector.clone().add(new Vector(
+				x <= 0 ? 0 : (ThreadLocalRandom.current().nextGaussian() / x),
+				y <= 0 ? 0 : (ThreadLocalRandom.current().nextGaussian() / y),
+				z <= 0 ? 0 : (ThreadLocalRandom.current().nextGaussian() / z)));
+	}
 }