From 6f34bb050ab1d636177ef08df487dcd5fcfc5a17 Mon Sep 17 00:00:00 2001
From: Luke Street <luke@street.dev>
Date: Wed, 22 Apr 2026 00:14:41 -0600
Subject: [PATCH] Call J3DModel::diff in mDoExt_modelEntryDL when interpolating

Fixes #355
---
 src/m_Do/m_Do_ext.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/m_Do/m_Do_ext.cpp b/src/m_Do/m_Do_ext.cpp
index 84bf51ecf5..fc8952e91d 100644
--- a/src/m_Do/m_Do_ext.cpp
+++ b/src/m_Do/m_Do_ext.cpp
@@ -351,8 +351,13 @@ void mDoExt_modelUpdateDL(J3DModel* i_model) {
 
 void mDoExt_modelEntryDL(J3DModel* i_model) {
 #if TARGET_PC
-    if (!dusk::frame_interp::is_sim_frame())
+    if (!dusk::frame_interp::is_sim_frame()) {
+        // FRAME INTERP NOTE: This fixes issue #355 where some lights would flicker.
+        // This is likely better solved by updating J3DMaterial::needsInterpCallBack,
+        // but it's unclear what exactly needs to be added.
+        i_model->diff();
         return;
+    }
 #endif
 
     modelMtxErrorCheck(i_model);