diff --git a/src/lol/math/geometry.h b/src/lol/math/geometry.h
index e3932397..03fb100d 100644
--- a/src/lol/math/geometry.h
+++ b/src/lol/math/geometry.h
@@ -184,7 +184,7 @@ vec3 ProjPointOnPlane(vec3 const &point, vec3 const &planeP, vec3 const &planeN)
 bool RayIsectPlane(vec3 const &rayP0, vec3 const &rayP1,
                    vec3 const &planeP, vec3 const &planeN,
                    vec3 &vIsec, bool test_line_only = false);
-
+bool TestPointInFrustum(const vec3& point, const mat4& frustum, vec3* result_point=nullptr);
 } /* namespace lol */
 
 #endif // __LOL_MATH_GEOMETRY_H__
diff --git a/src/math/geometry.cpp b/src/math/geometry.cpp
index 376b55f8..25644f02 100644
--- a/src/math/geometry.cpp
+++ b/src/math/geometry.cpp
@@ -289,5 +289,18 @@ namespace lol
         return true;
     }
 
+    //--
+    bool TestPointInFrustum(const vec3& point, const mat4& frustum, vec3* result_point)
+    {
+        vec4 proj_point = frustum * vec4(point, 1.f);
+        proj_point /= proj_point.w;
+
+        if (result_point)
+            *result_point = proj_point.xyz;
+        for (int i = 0; i < 3; i++)
+            if (lol::abs(proj_point[i]) > 1.f)
+                return false;
+        return true;
+    }
 } /* namespace lol */