return modf function

headers/vmath.hpp/vmath_fun.hpp

@@ -78,6 +78,12 @@ namespace vmath_hpp
         return std::fmod(x, y);
     }
 
+    template < typename T >
+    [[nodiscard]] std::enable_if_t<std::is_floating_point_v<T>, T>
+    modf(T x, T* y) noexcept {
+        return std::modf(x, y);
+    }
+
     template < typename T >
     [[nodiscard]] std::enable_if_t<std::is_floating_point_v<T>, T>
     copysign(T x, T s) noexcept {

headers/vmath.hpp/vmath_vec_fun.hpp

@@ -505,6 +505,20 @@ namespace vmath_hpp
         return map_join([](T x, T y) { return fmod(x, y); }, xs, ys);
     }
 
+    namespace impl
+    {
+        template < typename T, std::size_t Size, std::size_t... Is >
+        VMATH_HPP_FORCE_INLINE
+        vec<T, Size> modf_impl(const vec<T, Size>& xs, vec<T, Size>* is, std::index_sequence<Is...>) {
+            return { modf(xs[Is], &(*is)[Is])... };
+        }
+    }
+
+    template < typename T, std::size_t Size >
+    vec<T, Size> modf(const vec<T, Size>& xs, vec<T, Size>* is) {
+        return impl::modf_impl(xs, is, std::make_index_sequence<Size>{});
+    }
+
     template < typename T, std::size_t Size >
     [[nodiscard]] vec<T, Size> copysign(const vec<T, Size>& xs, T s) {
         return map_join([s](T x) { return copysign(x, s); }, xs);