diff options
author | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-05-12 02:17:50 +0300 |
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committer | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-05-22 00:08:13 +0300 |
commit | 8fc157a4be20a98dd412dc8ebf2149c97b775711 (patch) | |
tree | 94b642928960f550ae3395a0606318bf67f32380 | |
parent | 4ed368e68d4ba749fc0fe7cb0ef4568350aaa9aa (diff) |
Simplifying fast_atan2f()
-rw-r--r-- | src/analysis.c | 22 |
1 files changed, 8 insertions, 14 deletions
diff --git a/src/analysis.c b/src/analysis.c index fae0c660..95e79964 100644 --- a/src/analysis.c +++ b/src/analysis.c @@ -115,26 +115,20 @@ static const int extra_bands[NB_TOT_BANDS+1] = { #define cE ((float)M_PI/2) static OPUS_INLINE float fast_atan2f(float y, float x) { float x2, y2; - /* Should avoid underflow on the values we'll get */ - if (ABS16(x)+ABS16(y)<1e-9f) - { - x*=1e12f; - y*=1e12f; - } x2 = x*x; y2 = y*y; + /* For very small values, we don't care about the answer, so + we can just return 0. */ + if (x2 + y2 < 1e-18f) + { + return 0; + } if(x2<y2){ float den = (y2 + cB*x2) * (y2 + cC*x2); - if (den!=0) - return -x*y*(y2 + cA*x2) / den + (y<0 ? -cE : cE); - else - return (y<0 ? -cE : cE); + return -x*y*(y2 + cA*x2) / den + (y<0 ? -cE : cE); }else{ float den = (x2 + cB*y2) * (x2 + cC*y2); - if (den!=0) - return x*y*(x2 + cA*y2) / den + (y<0 ? -cE : cE) - (x*y<0 ? -cE : cE); - else - return (y<0 ? -cE : cE) - (x*y<0 ? -cE : cE); + return x*y*(x2 + cA*y2) / den + (y<0 ? -cE : cE) - (x*y<0 ? -cE : cE); } } |