From 097ded1bd06c66b2940025d2fa01e53310757358 Mon Sep 17 00:00:00 2001
From: Zeno Rogue <zeno@attnam.com>
Date: Mon, 7 Aug 2023 20:04:17 +0200
Subject: [PATCH] fix for nil model-changed christoffel

---
 nonisotropic.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/nonisotropic.cpp b/nonisotropic.cpp
index 3af86511..f233f350 100644
--- a/nonisotropic.cpp
+++ b/nonisotropic.cpp
@@ -803,10 +803,10 @@ EX namespace nilv {
       convert_tangent_ref(P, V, model_used, nmHeis);
       convert_tangent_ref(P, T, model_used, nmHeis);
       auto res = christoffel(P, V, T, nmHeis);
-      convert_tangent_ref(P, res, nmHeis, model_used);
-      // this is acceleration, not tangent, so:
-      res[2] += (model_used-nmHeis) * V[0] * V[1];
-      return res;
+
+      auto T1 = T + res;
+      convert_tangent_ref(P + V, T1, nmHeis, model_used);
+      return T1 - Transported;
       }
     }