Inverse Square

float Q_rsqrt( float number )
{
	long i;
	float x2, y;
	const float threehalfs = 1.5F;

	x2 = number * 0.5F;
	y  = number;
	i  = * ( long * ) &y;                       // evil floating point bit level hacking
	i  = 0x5f3759df - ( i >> 1 );               // what the fuck? 
	y  = * ( float * ) &i;
	y  = y * ( threehalfs - ( x2 * y * y ) );   // 1st iteration
//	y  = y * ( threehalfs - ( x2 * y * y ) );   // 2nd iteration, this can be removed

	return y;
}

Source: en.wikipedia.org

Similar codes

-2 votes286 views1 answer
How to make custom domain extension
C++
7 votes249 views4 answers
C++ hide console
C++
2 votes265 views1 answer
For loop reverse C++
C++
5 votes259 views1 answer
How to use comparator funtion in priority queue in c++
C++
17 votes273 views4 answers
How to reference a child gameobject unity
C++
1 vote277 views1 answer
C++ check if debug or release visual studio
C++
0 vote246 views1 answer
C++ add everything in a vector
C++
2 votes253 views2 answers
Run cmd command c++
C++
0 vote281 views1 answer
Get rest of a stringstream c++
C++
0 vote290 views1 answer
What is imposter syndrome
C++