Latte: Serialize screenshot requests

src/Cafe/HW/Latte/Renderer/Metal/MetalRenderer.cpp

@@ -413,6 +413,9 @@ void MetalRenderer::HandleScreenshotRequest(LatteTextureView* texView, bool padV
 	}
 	else
 		m_screenshot_state = ScreenshotState::None;
+	const auto screenshotRequestId = GetActiveScreenshotRequestId();
+	if (screenshotRequestId == 0)
+		return;
 
 	auto texMtl = static_cast<LatteTextureMtl*>(texView->baseTexture);
 
@@ -460,7 +463,7 @@ void MetalRenderer::HandleScreenshotRequest(LatteTextureView* texView, bool padV
 	}
 
 	if (formatValid)
-		SaveScreenshot(rgb_data, width, height, !padView);
+		SaveScreenshot(screenshotRequestId, rgb_data, width, height, !padView);
 }
 
 void MetalRenderer::DrawBackbufferQuad(LatteTextureView* texView, RendererOutputShader* shader, bool useLinearTexFilter,

src/Cafe/HW/Latte/Renderer/OpenGL/OpenGLRenderer.cpp

@@ -536,6 +536,9 @@ void OpenGLRenderer::HandleScreenshotRequest(LatteTextureView* texView, bool pad
 	}
 	else
 		m_screenshot_state = ScreenshotState::None;
+	const auto screenshotRequestId = GetActiveScreenshotRequestId();
+	if (screenshotRequestId == 0)
+		return;
 
 	int screenshotWidth, screenshotHeight;
 	glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
@@ -577,7 +580,7 @@ void OpenGLRenderer::HandleScreenshotRequest(LatteTextureView* texView, bool pad
 		}
 	}
 
-	SaveScreenshot(rgb_data, screenshotWidth, screenshotHeight, !padView);
+	SaveScreenshot(screenshotRequestId, rgb_data, screenshotWidth, screenshotHeight, !padView);
 }
 
 void OpenGLRenderer::DrawBackbufferQuad(LatteTextureView* texView, RendererOutputShader* shader, bool useLinearTexFilter, sint32 imageX, sint32 imageY, sint32 imageWidth, sint32 imageHeight, bool padView, bool clearBackground)

src/Cafe/HW/Latte/Renderer/Renderer.cpp

@@ -109,24 +109,70 @@ uint8 Renderer::RGBComponentToSRGB(uint8 cli)
 	return (uint8)(cs * 255.0f);
 }
 
-void Renderer::RequestScreenshot(ScreenshotSaveFunction onSaveScreenshot)
+std::optional<Renderer::ScreenshotRequestId> Renderer::RequestScreenshot(
+	ScreenshotSaveFunction onSaveScreenshot, std::optional<bool> mainWindow)
 {
+	std::lock_guard lock(m_screenshot_mutex);
+	if (!onSaveScreenshot || m_screenshot_active_request_id != 0 ||
+		m_screenshot_requested.load(std::memory_order_acquire) ||
+		m_screenshot_state.load(std::memory_order_acquire) != ScreenshotState::None)
+		return std::nullopt;
+	auto requestId = m_screenshot_next_request_id++;
+	if (requestId == 0)
+		requestId = m_screenshot_next_request_id++;
+	m_screenshot_active_request_id = requestId;
+	m_on_save_screenshot = std::move(onSaveScreenshot);
+	m_screenshot_main_window = mainWindow;
 	m_screenshot_requested = true;
-	m_on_save_screenshot = onSaveScreenshot;
+	return requestId;
+}
+
+bool Renderer::CancelScreenshotRequest(ScreenshotRequestId requestId)
+{
+	std::lock_guard lock(m_screenshot_mutex);
+	if (requestId == 0 || m_screenshot_active_request_id != requestId)
+		return false;
+	m_screenshot_requested = false;
+	m_on_save_screenshot = {};
+	m_screenshot_main_window.reset();
+	m_screenshot_active_request_id = 0;
+	return true;
 }
 
 void Renderer::CancelScreenshotRequest()
 {
+	std::lock_guard lock(m_screenshot_mutex);
 	m_screenshot_requested = false;
 	m_on_save_screenshot = {};
+	m_screenshot_main_window.reset();
+	m_screenshot_active_request_id = 0;
 }
 
 
-void Renderer::SaveScreenshot(const std::vector<uint8>& rgb_data, int width, int height, bool mainWindow)
+Renderer::ScreenshotRequestId Renderer::GetActiveScreenshotRequestId()
 {
+	std::lock_guard lock(m_screenshot_mutex);
+	return m_screenshot_active_request_id;
+}
+
+void Renderer::SaveScreenshot(ScreenshotRequestId requestId, const std::vector<uint8>& rgb_data,
+	int width, int height, bool mainWindow)
+{
+	ScreenshotSaveFunction onSaveScreenshot;
+	{
+		std::lock_guard lock(m_screenshot_mutex);
+		if (requestId == 0 || requestId != m_screenshot_active_request_id)
+			return;
+		if (m_screenshot_main_window.has_value() && m_screenshot_main_window.value() != mainWindow)
+			return;
+		m_screenshot_main_window.reset();
+		m_screenshot_requested = false;
+		onSaveScreenshot = std::move(m_on_save_screenshot);
+		m_screenshot_active_request_id = 0;
+	}
 	std::thread(
-		[=, screenshotRequested = std::exchange(m_screenshot_requested, false), onSaveScreenshot = std::exchange(m_on_save_screenshot, {})]() {
-			if (screenshotRequested && onSaveScreenshot)
+		[=, onSaveScreenshot = std::move(onSaveScreenshot)]() {
+			if (onSaveScreenshot)
 			{
 				auto notificationMessage = onSaveScreenshot(rgb_data, width, height, mainWindow);
 				if (notificationMessage.has_value())

src/Cafe/HW/Latte/Renderer/Renderer.h

@@ -68,7 +68,10 @@ public:
 	virtual void SwapBuffers(bool swapTV, bool swapDRC) = 0;
 
 	using ScreenshotSaveFunction = std::function<std::optional<std::string>(const std::vector<uint8>&, int, int, bool)>;
-	void RequestScreenshot(ScreenshotSaveFunction onSaveScreenshot);
+	using ScreenshotRequestId = uint64;
+	[[nodiscard]] std::optional<ScreenshotRequestId> RequestScreenshot(
+		ScreenshotSaveFunction onSaveScreenshot, std::optional<bool> mainWindow = {});
+	bool CancelScreenshotRequest(ScreenshotRequestId requestId);
 	void CancelScreenshotRequest();
 
 	virtual void HandleScreenshotRequest(LatteTextureView* texView, bool padView){}
@@ -175,11 +178,17 @@ protected:
 		Main,
 		Pad,
 	};
-	ScreenshotState m_screenshot_state = ScreenshotState::None;
-	bool m_screenshot_requested = false;
+	std::atomic<ScreenshotState> m_screenshot_state{ScreenshotState::None};
+	std::atomic_bool m_screenshot_requested{false};
+	std::mutex m_screenshot_mutex;
+	ScreenshotRequestId m_screenshot_next_request_id{1};
+	ScreenshotRequestId m_screenshot_active_request_id{};
 	ScreenshotSaveFunction m_on_save_screenshot;
+	std::optional<bool> m_screenshot_main_window;
 
-	void SaveScreenshot(const std::vector<uint8>& rgb_data, int width, int height, bool mainWindow);
+	[[nodiscard]] ScreenshotRequestId GetActiveScreenshotRequestId();
+	void SaveScreenshot(ScreenshotRequestId requestId, const std::vector<uint8>& rgb_data,
+		int width, int height, bool mainWindow);
 
 
 	ImFontAtlas* imguiFontAtlas{};

src/Cafe/HW/Latte/Renderer/Vulkan/VulkanRenderer.cpp

@@ -1022,6 +1022,9 @@ void VulkanRenderer::HandleScreenshotRequest(LatteTextureView* texView, bool pad
 	}
 	else
 		m_screenshot_state = ScreenshotState::None;
+	const auto screenshotRequestId = GetActiveScreenshotRequestId();
+	if (screenshotRequestId == 0)
+		return;
 
 	auto texViewVk = (LatteTextureViewVk*)texView;
 	auto baseImageTex = texViewVk->GetBaseImage();
@@ -1268,7 +1271,7 @@ void VulkanRenderer::HandleScreenshotRequest(LatteTextureView* texView, bool pad
 		vkFreeMemory(m_logicalDevice, imageMemory, nullptr);
 
 	if (formatValid)
-		SaveScreenshot(rgb_data, width, height, !padView);
+		SaveScreenshot(screenshotRequestId, rgb_data, width, height, !padView);
 }
 
 static const float kQueuePriority = 1.0f;

src/gui/wxgui/input/HotkeySettings.cpp

@@ -192,7 +192,7 @@ void HotkeySettings::Init(MainWindow* mainWindowFrame)
 		 }},
 		{&s_cfgHotkeys.takeScreenshot, [](void) {
 			 if (g_renderer)
-				 g_renderer->RequestScreenshot(SaveScreenshot);
+				 (void)g_renderer->RequestScreenshot(SaveScreenshot);
 		 }},
 		{&s_cfgHotkeys.toggleFastForward, [](void) {
 			 ActiveSettings::SetTimerShiftFactor((ActiveSettings::GetTimerShiftFactor() < 3) ? 3 : 1);