/* Copyright (c) 2012-2013 Jesper Öqvist <jesper@llbit.se>
*
* This file is part of Chunky.
*
* Chunky is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Chunky is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with Chunky. If not, see <http://www.gnu.org/licenses/>.
*/
package se.llbit.math;
/**
* Quick math utility methods.
*
* @author Jesper Öqvist <jesper@llbit.se>
*/
public class QuickMath {
public static final double HALF_PI = Math.PI / 2;
public static final double TAU = Math.PI * 2;
/**
* @return The floor of d
*/
public static long floor(double d) {
long i = (long) d;
return d < i ? i - 1 : i;
}
/**
* @return The ceil of d
*/
public static long ceil(double d) {
long i = (long) d;
return d > i ? i + 1 : i;
}
/**
* Get the next power of two.
*
* @return The next power of two
*/
public static int nextPow2(int x) {
x--;
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
x |= x >> 8;
x |= x >> 16;
return x + 1;
}
/**
* @return 2-logarithm of x
*/
public static int log2(int x) {
int v = 0;
while ((x >>>= 1) != 0) {
v += 1;
}
return v;
}
/**
* @return The sign of x
*/
public static int signum(double x) {
return x < 0 ? -1 : 1;
}
/**
* @return The sign of x
*/
public static int signum(float x) {
return x < 0 ? -1 : 1;
}
/**
* Convert radians to degrees
*
* @param rad Radians
* @return Degrees
*/
public static double radToDeg(double rad) {
return 180 * (rad / Math.PI);
}
/**
* @return Value modulo mod
*/
public static double modulo(double value, double mod) {
return ((value % mod) + mod) % mod;
}
/**
* Convert degrees to radians
*
* @param deg Degrees
* @return Radians
*/
public static double degToRad(double deg) {
return (deg * Math.PI) / 180;
}
/**
* @return value clamped to min and max
*/
public static double clamp(double value, double min, double max) {
return value < min ? min : value > max ? max : value;
}
/**
* NB not NaN-correct
*
* @return maximum value of a and b
*/
public static double max(double a, double b) {
return (a > b) ? a : b;
}
/**
* NB not NaN-correct
*
* @return maximum value of a and b
*/
public static float max(float a, float b) {
return (a > b) ? a : b;
}
/**
* NB disregards NaN. Don't use if a or b can be NaN
*
* @return minimum value of a and b
*/
public static double min(double a, double b) {
return (a < b) ? a : b;
}
/**
* NB disregards NaN. Don't use if a or b can be NaN
*
* @return minimum value of a and b
*/
public static float min(float a, float b) {
return (a < b) ? a : b;
}
/**
* NB disregards +-0
*
* @return absolute value of x
*/
public static float abs(float x) {
return (x < 0.f) ? -x : x;
}
/**
* NB disregards +-0
*
* @return absolute value of x
*/
public static double abs(double x) {
return (x < 0.0) ? -x : x;
}
}