org.luaj.platform.J2meMidp20Cldc11Platform Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of luaj-j2me Show documentation

Luaj 1.0.5 for the j2me platform

There is a newer version: 1.0.5

package org.luaj.platform;

import javax.microedition.midlet.MIDlet;

import org.luaj.lib.MathLib;
import org.luaj.vm.LDouble;
import org.luaj.vm.LNumber;

public class J2meMidp20Cldc11Platform extends J2meMidp10Cldc10Platform {
    public J2meMidp20Cldc11Platform(MIDlet midlet) {
        super(midlet);
    }
	
    public LNumber mathPow(LNumber base, LNumber exp) {
        return LDouble.numberOf(dpow(base.toJavaDouble(),exp.toJavaDouble()));
    }

	public LNumber mathop(int id, LNumber la, LNumber lb) {
		double a = la.toJavaDouble();
		double b = lb.toJavaDouble();
		double z = 0;
		switch ( id ) {
		default: return unsupportedMathOp();
		//case MathLib.ATAN2: z =
		//	b>0? Math.atan(a/b):
		//	b<0? (a>=0? Math.PI-Math.atan(a/-b): -Math.PI-Math.atan(a/-b)):
		//	(a>0? Math.PI/2: a<0? -Math.PI/2: 0);
		//	break;
		case MathLib.FMOD: z = a - (b * ((int)(a/b))); break;
		case MathLib.POW: z = dpow(a, b); break;
		}
		return LDouble.numberOf(z);
	}
	

	public LNumber mathop(int id, LNumber lx) {
		double x = lx.toJavaDouble();
		double z = 0;
		switch ( id ) {
		default: return unsupportedMathOp();
		case MathLib.ABS:   z = Math.abs(x); break;
		//case MathLib.ACOS:  z = Math.acos(x); break;
		//case MathLib.ASIN:  z = Math.asin(x); break;
		//case MathLib.ATAN:  z = Math.atan(x); break;
		case MathLib.COS:   z = Math.cos(x); break;
		//case MathLib.COSH:  z = (Math.exp(x) + Math.exp(-x)) / 2; break;
		case MathLib.DEG:   z = Math.toDegrees(x); break;
		//case MathLib.EXP:   z = Math.exp(x); break;
		//case MathLib.LOG:   z = Math.log(x); break;
		//case MathLib.LOG10: z = Math.log10(x); break;
		case MathLib.RAD:   z = Math.toRadians(x); break;
		case MathLib.SIN:   z = Math.sin(x); break;
		//case MathLib.SINH:  z = (Math.exp(x) - Math.exp(-x)) / 2; break;
		case MathLib.SQRT:  z = Math.sqrt(x); break;
		case MathLib.TAN:   z = Math.tan(x); break;
		//case MathLib.TANH: {
		//	double e = Math.exp(2*x);
		//	z = (e-1) / (e+1); 
		//	break;
		//}
		}
		return LDouble.numberOf(z);
	}

	public static double dpow(double a, double b) {
		if ( b < 0 )
			return 1 / dpow( a, -b );
		double p = 1;
		int whole = (int) b;
		for ( double v=a; whole > 0; whole>>=1, v*=v )
			if ( (whole & 1) != 0 )
				p *= v;
		if ( (b -= whole) > 0 ) {
			int frac = (int) (0x10000 * b);
			for ( ; (frac&0xffff)!=0; frac<<=1 ) {
				a = Math.sqrt(a);
				if ( (frac & 0x8000) != 0 )
					p *= a;
			}
		}
		return p;
	}
	
}