From 1fc942e47a5038cdc0b26ae380a22389617f19f2 Mon Sep 17 00:00:00 2001
From: James R <justsomejames2@gmail.com>
Date: Tue, 6 Apr 2021 18:17:04 -0700
Subject: [PATCH] Fix tilting on backward slopes

---
 src/p_mobj.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/p_mobj.c b/src/p_mobj.c
index d912d61cf..49165162d 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -1674,7 +1674,9 @@ void P_XYMovement(mobj_t *mo)
 						mo->momz = transfermomz;
 						mo->standingslope = NULL;
 						P_SetPitchRoll(mo, ANGLE_90,
-								transferslope->xydirection);
+								transferslope->xydirection
+								+ (transferslope->zangle
+									& ANGLE_180));
 						if (player)
 						{
 							player->powers[pw_justlaunched] = 2;