Math: make type traits aware of long double.

src/Math/MathTypeTraits.h

@@ -32,6 +32,14 @@
 #define DOUBLE_EQUALITY_PRECISION 1.0e-12
 #endif
 
+/**
+@brief Precision when testing long doubles for equality
+@todo some proper value please
+*/
+#ifndef LONG_DOUBLE_EQUALITY_PRECISION
+#define LONG_DOUBLE_EQUALITY_PRECISION 1.0e-18
+#endif
+
 namespace Magnum { namespace Math {
 
 /**
@@ -152,6 +160,11 @@ template<> struct MathTypeTraits<double>: Implementation::MathTypeTraitsFloating
 
     inline constexpr static double epsilon() { return DOUBLE_EQUALITY_PRECISION; }
 };
+template<> struct MathTypeTraits<long double>: Implementation::MathTypeTraitsFloatingPoint<long double> {
+    typedef long double FloatingPointType;
+
+    inline constexpr static long double epsilon() { return LONG_DOUBLE_EQUALITY_PRECISION; }
+};
 #endif
 
 }}