diff --git a/glm/gtx/matrix_interpolation.inl b/glm/gtx/matrix_interpolation.inl
index bd58d2f3..28c3e816 100644
--- a/glm/gtx/matrix_interpolation.inl
+++ b/glm/gtx/matrix_interpolation.inl
@@ -78,10 +78,18 @@ namespace glm
 		if (glm::abs(s) < T(0.001))
 			s = static_cast<T>(1);
 		T const angleCos = (m[0][0] + m[1][1] + m[2][2] - static_cast<T>(1)) * static_cast<T>(0.5);
-		if(abs(angleCos - static_cast<T>(1)) < epsilon)
-			angle = pi<T>() * static_cast<T>(0.25);
+		if(angleCos >= static_cast<T>(1.0))
+		{
+			angle = static_cast<T>(0.0);
+		}
+		else if (angleCos <= static_cast<T>(-1.0))
+		{
+			angle = pi<T>();
+		}
 		else
+		{
 			angle = acos(angleCos);
+		}
 		axis.x = (m[1][2] - m[2][1]) / s;
 		axis.y = (m[2][0] - m[0][2]) / s;
 		axis.z = (m[0][1] - m[1][0]) / s;