package gl_engine;

import gl_engine.vec.Vec2d;
import gl_engine.vec.Vec3d;

public class MathHelpers
{
	public static final double FallSpeed = 0.00098;
	
	public static double nextPowerOf(double x, double n)
	{
		double i = 1;
		
		while(i < x) {
			i *= n;
		}
		
		return i;
	}
	
	public static int nextPowerOf(double x, int n)
	{
		int i = 1;
		
		while(i < x) {
			i *= n;
		}
		
		return i;
	}
	
	public static double squared(double x) {
		return x*x;
	}
	
	public static double pow(int c, double x)
	{
		double res = 1;
		
		for(int i=0;i<c;i++) {
			res *= x;
		}
		
		return res;
	}
	
	public static double distance3d(double x1, double y1, double z1, double x2, double y2, double z2) {
		return Math.sqrt( squared(x2 - x1) + squared(y2 - y1) + squared(z2 - z1) );
	}
	
	public static double distance2d(double x1, double y1, double x2, double y2) {
		return Math.sqrt( squared(x2 - x1) + squared(y2 - y1) );
	}
	
	public static double map(double x, double in_min, double in_max, double out_min, double out_max) {
		return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
	}
	
	public static Vec2d moveTowards2(double amount, double angle) {
		return new Vec2d(Math.sin(angle) * amount, Math.cos(angle) * amount);
	}
	
	public static Vec3d moveTowards3(double amount, Vec2d angles)
	{
		// Create some varibles
	    Vec3d points = new Vec3d(0, 0, 0);
	    double m;
	    
	    points.z = Math.sin(angles.y) * amount;
	    m = Math.cos(angles.y);
	    points.x = Math.sin(angles.x) * m * amount;
	    m = Math.cos(angles.x) * m;
	    points.y = m * amount;

	    return points;
	}
	
	public static double mod(double a, double b) {
		return (((a % b) + b) % b);
	}
	
	public static int mod(int a, int b) {
		return (((a % b) + b) % b);
	}
	
	public static int floor(double a)
	{
		if((int)a == a) {
			return (int) a;
		}
		
		else if(a < 0) {
			return (int)(a - 1);
		}
		
		else {
			return (int)a;
		}
	}
	
	public static double positive(double a) {
		if(a < 0) return -a;
		else return a;
	}
	
	public static int positive(int a) {
		if(a < 0) return -a;
		else return a;
	}
	
	public static Vec2d rotate2(Vec2d pos, double angle)
	{
		// Calculate 2 sin and cos values
		double s = Math.sin(angle);
		double c = Math.cos(angle);
		
		// Return and calculate the new positions
		return new Vec2d(
				pos.x * c - pos.y * s,
				pos.x * s + pos.y * c);
	}
	
	public static double biggest(double a, double b)
	{
		if(a > b) return a;
		else return b;
	}
	
	public static double smallest(double a, double b)
	{
		if(a < b) return a;
		else return b;
	}
}