diff --git a/inc/hgl/math/Vector.h b/inc/hgl/math/Vector.h
index 9d44301..04a1ce9 100644
--- a/inc/hgl/math/Vector.h
+++ b/inc/hgl/math/Vector.h
@@ -106,6 +106,14 @@ namespace hgl
         return Vector3f(src.x,src.y,z);
     }
 
+    template<typename T>
+    inline T clamp(const T &v,const T &min_v,const T &max_v)
+    {
+        if(v<min_v)return min_v;
+        if(v>max_v)return max_v;
+        return v;
+    }
+
     template<typename T>
     inline T normalized(const T &v)
     {
@@ -130,6 +138,12 @@ namespace hgl
         return v1.Dot(v2);
     }
 
+    template<typename T>
+    inline float dot2(const T &v)
+    {
+        return v.Dot(v);
+    }
+
     inline float ray_angle_cos(const Ray &ray,const vec &pos)
     {
         return ray.dir.Dot((pos-ray.pos).Normalized());