From 35a06ed175af5e070cbbd3cebde2906c24e2c50f Mon Sep 17 00:00:00 2001
From: toaster <rollerorbital@gmail.com>
Date: Mon, 18 Sep 2023 17:32:25 +0100
Subject: [PATCH] P_SetupSignObject: Set old_z to fix interp on spawning

---
 src/p_spec.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/p_spec.c b/src/p_spec.c
index 79cb28377..a9dc3760f 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -4488,6 +4488,7 @@ static void P_SetupSignObject(mobj_t *sign, mobj_t *pmo, boolean error)
 
 	sign->movefactor = sign->z;
 	sign->z += (576*sign->scale) * P_MobjFlip(sign);
+	sign->old_z = sign->z; // interp hijack
 	sign->movecount = 1;
 	sign->extravalue1 = AngleFixed(sign->angle) >> FRACBITS;