From d73726b0a701c6cb56765b311662f51b4c0ae52c Mon Sep 17 00:00:00 2001
From: Callan Barrett <callan@zoocar.org>
Date: Mon, 31 Aug 2026 10:16:31 +0800
Subject: [PATCH] fix(zaparoo): restore menu static background

---
 support/zaparoo/alt_launcher.cpp | 11 +++++++++++
 support/zaparoo/alt_launcher.h   |  2 ++
 user_io.cpp                      |  1 +
 3 files changed, 14 insertions(+)

diff --git a/support/zaparoo/alt_launcher.cpp b/support/zaparoo/alt_launcher.cpp
index 892b99671..746d22647 100644
--- a/support/zaparoo/alt_launcher.cpp
+++ b/support/zaparoo/alt_launcher.cpp
@@ -297,6 +297,14 @@ static void zero_native_crt_words(void)
 	shmem_unmap(p, map_size);
 }
 
+// The menu core's native video reader activates on any non-zero control word
+// at 0x3A000000 and that core no longer clears DDR on startup, so a previous
+// core's leftovers make it scan out garbage instead of its noise background.
+void zaparoo_native_video_release(void)
+{
+	zero_native_crt_words();
+}
+
 static void clear_launcher_tty(void)
 {
 	int tty_fd = open(s_tty_path, O_WRONLY | O_CLOEXEC);
@@ -1015,6 +1023,9 @@ void alt_launcher_poll(void)
 void alt_launcher_shutdown(void)
 {
 	fflush(stdout);
+	// Every FPGA reconfiguration passes through here, so the incoming core
+	// cannot inherit a stale native video control block.
+	zero_native_crt_words();
 	if (!s_pid)
 	{
 		if (alt_launcher_configured()) kill_stale_frontends();
diff --git a/support/zaparoo/alt_launcher.h b/support/zaparoo/alt_launcher.h
index 13485ce13..4333956ac 100644
--- a/support/zaparoo/alt_launcher.h
+++ b/support/zaparoo/alt_launcher.h
@@ -44,3 +44,5 @@ bool zaparoo_is_native_core(void);
 void zaparoo_alt_launcher_init_for_core(void);
 void zaparoo_alt_launcher_init_for_menu(void);
 void zaparoo_alt_launcher_start_for_menu(void);
+// Parks the menu core on its own background until a writer publishes frames.
+void zaparoo_native_video_release(void);
diff --git a/user_io.cpp b/user_io.cpp
index a897b7b8e..a7f9d05b4 100644
--- a/user_io.cpp
+++ b/user_io.cpp
@@ -1573,6 +1573,7 @@ void user_io_init(const char *path, const char *xml)
 			else if (is_menu())
 			{
 				user_io_status_set("[4]", (cfg.menu_pal) ? 1 : 0);
+				zaparoo_native_video_release();
 				if (alt_launcher_configured())
 				{
 					if (rbf_path[0] || !zaparoo_is_native_core()) zaparoo_alt_launcher_init_for_menu();