diff --git a/libs/geom/include/psemek/geom/math.hpp b/libs/geom/include/psemek/geom/math.hpp
index b74dc013..8e3d832d 100644
--- a/libs/geom/include/psemek/geom/math.hpp
+++ b/libs/geom/include/psemek/geom/math.hpp
@@ -155,15 +155,17 @@ namespace psemek::geom
 	}
 
 	template <typename T>
-	T idiv(T x, T m)
+	T imod(T x, T m)
 	{
-		return (x >= 0) ? (x / m) : -((- x + m - 1) / m);
+		static_assert(std::is_integral_v<T>);
+		return ((x % m) + m) % m;
 	}
 
 	template <typename T>
-	T imod(T x, T m)
+	T idiv(T x, T m)
 	{
-		return x - m * idiv(x, m);
+		static_assert(std::is_integral_v<T>);
+		return (x - imod(x, m)) / m;
 	}
 
 	template <typename T>