Fix NumberEquals with unsigned

Former-commit-id: 30b573278e84991a9d76604a359bd3110f13d87c

include/Nazara/Math/Algorithm.hpp

@@ -16,6 +16,10 @@
 #define M_PI 3.141592653589793238462643
 #endif
 
+#ifndef M_PI_2
+#define M_PI_2  1.5707963267948966192313217
+#endif
+
 #ifndef M_SQRT2
 #define M_SQRT2 1.4142135623730950488016887
 #endif

include/Nazara/Math/Algorithm.inl

@@ -223,10 +223,10 @@ T NzNormalizeAngle(T angle)
 template<typename T>
 bool NzNumberEquals(T a, T b, T maxDifference)
 {
-	T diff = a - b;
-	if (diff < F(0.0))
-		diff = -diff;
+	if (b > a)
+		std::swap(a, b);
 
+	T diff = a - b;
 	return diff <= maxDifference;
 }