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Codechange: Replace custom rounded square root logic with standard library functions

pull/12200/head
c-mon 2024-03-01 18:00:22 +01:00
parent f0a891c4f7
commit 364bafc38d
1 changed files with 1 additions and 21 deletions
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22
src/core/math_func.cpp
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@ -37,28 +37,8 @@ int DivideApprox(int a, int b)
* Compute the integer square root. * Compute the integer square root.
* @param num Radicand. * @param num Radicand.
* @return Rounded integer square root. * @return Rounded integer square root.
* @note Algorithm taken from http://en.wikipedia.org/wiki/Methods_of_computing_square_roots
*/ */
uint32_t IntSqrt(uint32_t num) uint32_t IntSqrt(uint32_t num)
{ {
uint32_t res = 0; return (uint32_t)round(sqrt(num));
uint32_t bit = 1UL << 30; // Second to top bit number.
/* 'bit' starts at the highest power of four <= the argument. */
while (bit > num) bit >>= 2;
while (bit != 0) {
if (num >= res + bit) {
num -= res + bit;
res = (res >> 1) + bit;
} else {
res >>= 1;
}
bit >>= 2;
}
/* Arithmetic rounding to nearest integer. */
if (num > res) res++;
return res;
} }