package com.intellectualcrafters.plot.util;
public class MathMan {
private static final int ATAN2_BITS = 7;
private static final int ATAN2_BITS2 = ATAN2_BITS << 1;
private static final int ATAN2_MASK = ~(-1 << ATAN2_BITS2);
private static final int ATAN2_COUNT = ATAN2_MASK + 1;
private static final int ATAN2_DIM = (int) Math.sqrt(ATAN2_COUNT);
private static final float INV_ATAN2_DIM_MINUS_1 = 1.0f / (ATAN2_DIM - 1);
private static final float[] atan2 = new float[ATAN2_COUNT];
private static final int[] table = {
0, 16, 22, 27, 32, 35, 39, 42, 45, 48, 50, 53, 55, 57,
59, 61, 64, 65, 67, 69, 71, 73, 75, 76, 78, 80, 81, 83,
84, 86, 87, 89, 90, 91, 93, 94, 96, 97, 98, 99, 101, 102,
103, 104, 106, 107, 108, 109, 110, 112, 113, 114, 115, 116, 117, 118,
119, 120, 121, 122, 123, 124, 125, 126, 128, 128, 129, 130, 131, 132,
133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 144, 145,
146, 147, 148, 149, 150, 150, 151, 152, 153, 154, 155, 155, 156, 157,
158, 159, 160, 160, 161, 162, 163, 163, 164, 165, 166, 167, 167, 168,
169, 170, 170, 171, 172, 173, 173, 174, 175, 176, 176, 177, 178, 178,
179, 180, 181, 181, 182, 183, 183, 184, 185, 185, 186, 187, 187, 188,
189, 189, 190, 191, 192, 192, 193, 193, 194, 195, 195, 196, 197, 197,
198, 199, 199, 200, 201, 201, 202, 203, 203, 204, 204, 205, 206, 206,
207, 208, 208, 209, 209, 210, 211, 211, 212, 212, 213, 214, 214, 215,
215, 216, 217, 217, 218, 218, 219, 219, 220, 221, 221, 222, 222, 223,
224, 224, 225, 225, 226, 226, 227, 227, 228, 229, 229, 230, 230, 231,
231, 232, 232, 233, 234, 234, 235, 235, 236, 236, 237, 237, 238, 238,
239, 240, 240, 241, 241, 242, 242, 243, 243, 244, 244, 245, 245, 246,
246, 247, 247, 248, 248, 249, 249, 250, 250, 251, 251, 252, 252, 253,
253, 254, 254, 255
};
static {
for (int i = 0; i < ATAN2_DIM; i++) {
for (int j = 0; j < ATAN2_DIM; j++) {
float x0 = (float) i / ATAN2_DIM;
float y0 = (float) j / ATAN2_DIM;
atan2[(j * ATAN2_DIM) + i] = (float) Math.atan2(y0, x0);
}
}
}
public static long pairInt(int x, int y) {
return (((long)x) << 32) | (y & 0xffffffffL);
}
public static int unpairIntX(long pair) {
return (int)(pair >> 32);
}
public static int unpairIntY(long pair) {
return (int)pair;
}
public static byte pair16(byte x, byte y) {
return (byte) (x + (y << 4));
}
public static byte unpair16x(byte value) {
return (byte) (value & 0xF);
}
public static byte unpair16y(byte value) {
return (byte) ((value >> 4) & 0xF);
}
public static long inverseRound(double val) {
long round = Math.round(val);
return (long) (round + Math.signum(val - round));
}
public static int sqrt(int x) {
int xn;
if (x >= 0x10000) {
if (x >= 0x1000000) {
if (x >= 0x10000000) {
if (x >= 0x40000000) {
xn = table[x >> 24] << 8;
} else {
xn = table[x >> 22] << 7;
}
} else {
if (x >= 0x4000000) {
xn = table[x >> 20] << 6;
} else {
xn = table[x >> 18] << 5;
}
}
xn = (xn + 1 + (x / xn)) >> 1;
xn = (xn + 1 + (x / xn)) >> 1;
return ((xn * xn) > x) ? --xn : xn;
} else {
if (x >= 0x100000) {
if (x >= 0x400000) {
xn = table[x >> 16] << 4;
} else {
xn = table[x >> 14] << 3;
}
} else {
if (x >= 0x40000) {
xn = table[x >> 12] << 2;
} else {
xn = table[x >> 10] << 1;
}
}
xn = (xn + 1 + (x / xn)) >> 1;
return ((xn * xn) > x) ? --xn : xn;
}
} else {
if (x >= 0x100) {
if (x >= 0x1000) {
if (x >= 0x4000) {
xn = (table[x >> 8]) + 1;
} else {
xn = (table[x >> 6] >> 1) + 1;
}
} else {
if (x >= 0x400) {
xn = (table[x >> 4] >> 2) + 1;
} else {
xn = (table[x >> 2] >> 3) + 1;
}
}
return ((xn * xn) > x) ? --xn : xn;
} else {
if (x >= 0) {
return table[x] >> 4;
}
}
}
throw new IllegalArgumentException("Invalid number:" + x);
}
public static double getMean(int[] array) {
double count = 0;
for (int i : array) {
count += i;
}
return count / array.length;
}
public static double getMean(double[] array) {
double count = 0;
for (double i : array) {
count += i;
}
return count / array.length;
}
public static int pair(short x, short y) {
return (x << 16) | (y & 0xFFFF);
}
public static final int average(int a, int b) {
return (a&b) + (a^b)/2;
}
public static short unpairX(int hash) {
return (short) (hash >> 16);
}
public static short unpairY(int hash) {
return (short) (hash & 0xFFFF);
}
/**
* Returns [x, y, z]
* @param yaw
* @param pitch
* @return
*/
public static float[] getDirection(float yaw, float pitch) {
double pitch_sin = Math.sin(pitch);
return new float[]{(float) (pitch_sin * Math.cos(yaw)), (float) (pitch_sin * Math.sin(yaw)), (float) Math.cos(pitch)};
}
public static int roundInt(double value) {
return (int) (value < 0 ? (value == (int) value) ? value : value - 1 : value);
}
/**
* Returns [ pitch, yaw ]
* @param x
* @param y
* @param z
* @return
*/
public static float[] getPitchAndYaw(float x, float y, float z) {
float distance = sqrtApprox((z * z) + (x * x));
return new float[]{atan2(y, distance), atan2(x, z)};
}
public static final float atan2(float y, float x) {
float add;
float mul;
if (x < 0.0f) {
if (y < 0.0f) {
x = -x;
y = -y;
mul = 1.0f;
} else {
x = -x;
mul = -1.0f;
}
add = -3.141592653f;
} else {
if (y < 0.0f) {
y = -y;
mul = -1.0f;
} else {
mul = 1.0f;
}
add = 0.0f;
}
float invDiv = 1.0f / (((x < y) ? y : x) * INV_ATAN2_DIM_MINUS_1);
int xi = (int) (x * invDiv);
int yi = (int) (y * invDiv);
return (atan2[(yi * ATAN2_DIM) + xi] + add) * mul;
}
public static float sqrtApprox(float f) {
return f * Float.intBitsToFloat(0x5f375a86 - (Float.floatToIntBits(f) >> 1));
}
public static double sqrtApprox(double d) {
return Double.longBitsToDouble(((Double.doubleToLongBits(d) - (1L << 52)) >> 1) + (1L << 61));
}
public static float invSqrt(float x) {
float xhalf = 0.5f * x;
int i = Float.floatToIntBits(x);
i = 0x5f3759df - (i >> 1);
x = Float.intBitsToFloat(i);
x = x * (1.5f - (xhalf * x * x));
return x;
}
public static int getPositiveId(int i) {
if (i < 0) {
return (-i * 2) - 1;
}
return i * 2;
}
public static boolean isInteger(String str) {
if (str == null) {
return false;
}
int length = str.length();
if (length == 0) {
return false;
}
int i = 0;
if (str.charAt(0) == '-') {
if (length == 1) {
return false;
}
i = 1;
}
for (; i < length; i++) {
char c = str.charAt(i);
if ((c <= '/') || (c >= ':')) {
return false;
}
}
return true;
}
public static double getSD(double[] array, double av) {
double sd = 0;
for (double element : array) {
sd += Math.pow(Math.abs(element - av), 2);
}
return Math.sqrt(sd / array.length);
}
public static double getSD(int[] array, double av) {
double sd = 0;
for (int element : array) {
sd += Math.pow(Math.abs(element - av), 2);
}
return Math.sqrt(sd / array.length);
}
public static int mod(int x, int y) {
if (isPowerOfTwo(y)) {
return x & (y - 1);
}
return x % y;
}
public static int unsignedmod(int x, int y) {
if (isPowerOfTwo(y)) {
return x & (y - 1);
}
return x % y;
}
public static boolean isPowerOfTwo(int number) {
return (number & (number - 1)) == 0;
}
}