diff --git a/interfaces/Crafter.Math-Ray.cppm b/interfaces/Crafter.Math-Ray.cppm
index cadbe3e..e9a8ac1 100755
--- a/interfaces/Crafter.Math-Ray.cppm
+++ b/interfaces/Crafter.Math-Ray.cppm
@@ -23,7 +23,7 @@ import std;
 
 namespace Crafter {
     export template<typename T>
-	T IntersectionTestRayTriangle(Vector<T, 3, 0> vert0, Vector<T, 3, 0> vert1, Vector<T, 3, 0> vert2, Vector<T, 3, 0> rayOrigin, Vector<T, 3, 0> rayDir) {
+	constexpr T IntersectionTestRayTriangle(Vector<T, 3, 0> vert0, Vector<T, 3, 0> vert1, Vector<T, 3, 0> vert2, Vector<T, 3, 0> rayOrigin, Vector<T, 3, 0> rayDir) {
         constexpr float EPSILON = 0.0000001;
         Vector<T, 3, 0> edge1 = vert1 - vert0;
         Vector<T, 3, 0> edge2 = vert2 - vert0;