inline short int GetHeadingFromVector(float dx,float dz)
{
	float h;
	//printf("(%.2f,%.2f)\n",dx,dz);
	if(dz!=0){
		float d=dx/dz;
		if(d > 1){
			h=(PI/2) - d/(d*d + 0.28f);
		} else if (d < -1){
			h=-(PI/2) - d/(d*d + 0.28f);
		}else{
			h=d/(1 + 0.28f * d*d);
		}
		if (dz<0) {
		  if (dx>0)
		    h+=PI;
		  else
		    h-=PI;
		}

	} else {
		if(dx>0)
			h=PI/2;
		else
			h=-PI/2;
	}

	h*=SHORTINT_MAXVALUE/PI;

	// Prevents h from going beyond SHORTINT_MAXVALUE.
	// If h goes beyond SHORTINT_MAXVALUE, the following 
	// conversion to a short int crashes.
//	if (h > SHORTINT_MAXVALUE) h=SHORTINT_MAXVALUE;
//	return (short int) h;

	int ih = (int) h;
	ih %= SHORTINT_MAXVALUE;
	return (short int)ih;

/*
	float wantedHeading;

	if(dz!=0)
		wantedHeading=atanf(dx/dz);
	else
		wantedHeading=PI;
	if(dz<0)
		wantedHeading+=PI;

	wantedHeading*=32768/PI;

	return wantedHeading;*/
}
struct shortint2{
	short int x,y;
};

//vec should be normalized
inline shortint2 GetHAndPFromVector(const float3& vec)
{
	shortint2 ret;

	// Prevents ret.y from going beyond SHORTINT_MAXVALUE.
	// If h goes beyond SHORTINT_MAXVALUE, the following 
	// conversion to a short int crashes.
	//this change destroys the whole meaning with using short ints....
	int iy = (int) (asin(vec.y)*(SHORTINT_MAXVALUE/PI));
	iy %= SHORTINT_MAXVALUE;
	ret.y=(short int) iy;
	ret.x=GetHeadingFromVector(vec.x, vec.z);
	return ret;
}