From b43abd201556a307f4099445c1c04fcf6fd5d9d2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Henrik=20Rydg=C3=A5rd?= <hrydgard@gmail.com>
Date: Thu, 17 Oct 2024 21:09:04 +0200
Subject: [PATCH] Fix issues with savestates and non-buffered rendering

---
 Core/SaveState.cpp | 16 ++++++++++------
 Core/SaveState.h   |  2 +-
 Core/System.cpp    |  1 -
 UI/EmuScreen.cpp   |  6 ++++++
 4 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/Core/SaveState.cpp b/Core/SaveState.cpp
index 9b713943c3..bc3950e15c 100644
--- a/Core/SaveState.cpp
+++ b/Core/SaveState.cpp
@@ -913,25 +913,26 @@ namespace SaveState
 		return Status::SUCCESS;
 	}
 
-	void Process()
-	{
+	// NOTE: This can cause ending of the current renderpass, due to the readback needed for the screenshot.
+	bool Process() {
 		rewindStates.Process();
 
 		if (!needsProcess)
-			return;
+			return false;
 		needsProcess = false;
 
 		if (!__KernelIsRunning())
 		{
 			ERROR_LOG(Log::SaveState, "Savestate failure: Unable to load without kernel, this should never happen.");
-			return;
+			return false;
 		}
 
 		std::vector<Operation> operations = Flush();
 		SaveStart state;
 
-		for (size_t i = 0, n = operations.size(); i < n; ++i)
-		{
+		bool readbackImage = false;
+
+		for (size_t i = 0, n = operations.size(); i < n; ++i) {
 			Operation &op = operations[i];
 			CChunkFileReader::Error result;
 			Status callbackResult;
@@ -1068,6 +1069,7 @@ namespace SaveState
 				} else {
 					screenshotFailures = 0;
 				}
+				readbackImage = true;
 				break;
 			}
 			default:
@@ -1083,6 +1085,8 @@ namespace SaveState
 			// Avoid triggering frame skipping due to slowdown
 			__DisplaySetWasPaused();
 		}
+
+		return readbackImage;
 	}
 
 	void NotifySaveData() {
diff --git a/Core/SaveState.h b/Core/SaveState.h
index b059725d52..32431218ef 100644
--- a/Core/SaveState.h
+++ b/Core/SaveState.h
@@ -104,7 +104,7 @@ namespace SaveState
 	bool IsOldVersion();
 
 	// Check if there's any save stating needing to be done.  Normally called once per frame.
-	void Process();
+	bool Process();
 
 	// Notify save state code that new save data has been written.
 	void NotifySaveData();
diff --git a/Core/System.cpp b/Core/System.cpp
index 155c3bbba3..9bca1c1705 100644
--- a/Core/System.cpp
+++ b/Core/System.cpp
@@ -623,7 +623,6 @@ void PSP_RunLoopWhileState() {
 }
 
 void PSP_RunLoopUntil(u64 globalticks) {
-	SaveState::Process();
 	if (coreState == CORE_POWERDOWN || coreState == CORE_BOOT_ERROR || coreState == CORE_RUNTIME_ERROR) {
 		return;
 	} else if (coreState == CORE_STEPPING) {
diff --git a/UI/EmuScreen.cpp b/UI/EmuScreen.cpp
index f374228b64..202dc5052a 100644
--- a/UI/EmuScreen.cpp
+++ b/UI/EmuScreen.cpp
@@ -1445,6 +1445,12 @@ ScreenRenderFlags EmuScreen::render(ScreenRenderMode mode) {
 	uint32_t clearColor = 0;
 	if (!blockedExecution) {
 		PSP_BeginHostFrame();
+		if (SaveState::Process()) {
+			// We might have lost the framebuffer bind if we had one, due to a readback.
+			if (framebufferBound) {
+				draw->BindFramebufferAsRenderTarget(nullptr, { RPAction::CLEAR, RPAction::CLEAR, RPAction::CLEAR, clearColor }, "EmuScreen_SavestateRebind");
+			}
+		}
 		PSP_RunLoopWhileState();
 
 		flags |= ScreenRenderFlags::HANDLED_THROTTLING;