diff options
Diffstat (limited to 'indra/llmath')
| -rw-r--r-- | indra/llmath/llmath.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/indra/llmath/llmath.h b/indra/llmath/llmath.h index ad8ced9e1a..5fd365086f 100644 --- a/indra/llmath/llmath.h +++ b/indra/llmath/llmath.h @@ -79,6 +79,27 @@ inline BOOL is_approx_equal(F32 x, F32 y) return (abs((S32) ((U32&)x - (U32&)y) ) < COMPARE_MANTISSA_UP_TO_BIT); } +inline BOOL is_approx_equal_fraction(F32 x, F32 y, U32 frac_bits) +{ + BOOL ret = TRUE; + F32 diff = (F32) fabs(x - y); + + S32 diffInt = (S32) diff; + S32 diffFracTolerance = (S32) ((diff - (F32) diffInt) * (1 << frac_bits)); + + // if integer portion is not equal, not enough bits were used for packing + // so error out since either the use case is not correct OR there is + // an issue with pack/unpack. should fail in either case. + // for decimal portion, make sure that the delta is no more than 1 + // based on the number of bits used for packing decimal portion. + if (diffInt != 0 || diffFracTolerance > 1) + { + ret = FALSE; + } + + return ret; +} + inline S32 llabs(const S32 a) { return S32(labs(a)); |