Speedup for microcontrast, issue #3867

2017-05-08 18:42:13 +02:00
parent af09d56b3b
commit 8b44ed0fd8
2 changed files with 166 additions and 253 deletions
--- a/rtengine/rt_math.h
+++ b/rtengine/rt_math.h
@@ -87,6 +87,13 @@ constexpr T CLIP(const T& a)
    return LIM(a, static_cast<T>(0), static_cast<T>(MAXVAL));
 }

+template <typename T>
+constexpr T SGN(const T& a)
+{
+    // returns -1 for a < 0, 0 for a = 0 and +1 for a > 0
+    return (T(0) < a) - (a < T(0));
+}
+
 template<typename T>
 constexpr T intp(T a, T b, T c)
 {