diff --git a/src/collision.c b/src/collision.c
index 15bd2d9..dfe646c 100644
--- a/src/collision.c
+++ b/src/collision.c
@@ -86,8 +86,7 @@ int _internal_collision_get_overlap(PhysicsEntity self, PhysicsEntity other, Col
 
     RigidBody* rba = self.tc->get_rigidbody(self.data);
     RigidBody* rbb = other.tc->get_rigidbody(other.data);
-    Vector velocity = rigidbody_get_velocity(rba);
-    velocity = vsubf(velocity, rigidbody_get_velocity(rbb));
+    Vector velocity = vsubf(rigidbody_get_velocity(rba), rigidbody_get_velocity(rbb));
 
     *out = (Collision) {
         .other = other,