feat: add wallpaper transitions, store crop in database per-wallpaper, move CUDA context creation to async thread

Plugins/ZShell/Internal/videoplayer.cpp

@@ -184,9 +184,13 @@ void VideoPlayer::closeDecoder() {
 	m_streamIndex = -1;
 }
 
-void VideoPlayer::decodeLoop(const QString& path) {
+void VideoPlayer::decodeLoop(const QString& path, uint32_t generation) {
+	if (!m_threadRunning.load(std::memory_order_acquire) ||
+		m_generation.load(std::memory_order_acquire) != generation)
+		return;
+
 	if (!openDecoder(path)) {
-		m_threadRunning = false;
+		m_threadRunning.store(false);
 		return;
 	}
 
@@ -198,13 +202,14 @@ void VideoPlayer::decodeLoop(const QString& path) {
 
 	AVFrame* frame = av_frame_alloc();
 	if (!frame) {
-		m_threadRunning = false;
+		m_threadRunning.store(false);
 		return;
 	}
 
 	AVPacket pkt{};
 
-	while (m_threadRunning) {
+	while (m_threadRunning.load(std::memory_order_acquire) &&
+		   m_generation.load(std::memory_order_acquire) == generation) {
 		int ret = av_read_frame(m_fmt, &pkt);
 		if (ret == AVERROR_EOF) {
 			if (avformat_seek_file(
@@ -230,7 +235,9 @@ void VideoPlayer::decodeLoop(const QString& path) {
 		}
 		av_packet_unref(&pkt);
 
-		while (m_threadRunning && avcodec_receive_frame(m_codec, frame) == 0) {
+		while (m_threadRunning.load(std::memory_order_acquire) &&
+			   m_generation.load(std::memory_order_acquire) == generation &&
+			   avcodec_receive_frame(m_codec, frame) == 0) {
 			bool wasEmpty = false;
 			{
 				std::lock_guard<std::mutex> lock(m_mtx);
@@ -251,21 +258,34 @@ void VideoPlayer::decodeLoop(const QString& path) {
 
 	av_frame_free(&frame);
 	closeDecoder();
-	m_threadRunning = false;
+	m_threadRunning.store(false);
 }
 
 bool VideoPlayer::start(const QString& path) {
-	stop();
+	const uint32_t generation =
+		m_generation.fetch_add(1, std::memory_order_acq_rel) + 1;
+	m_threadRunning.store(true);
 
-	if (!ensureCudaContext()) return false;
+	std::thread previous = std::move(m_thread);
+	m_thread = std::thread(
+		[this, path, generation, previous = std::move(previous)]() mutable {
+			if (previous.joinable()) previous.join();
+			closeDecoder();
+
+			if (!ensureCudaContext()) {
+				m_threadRunning.store(false);
+				return;
+			}
+
+			decodeLoop(path, generation);
+		});
 
-	m_threadRunning = true;
-	m_thread = std::thread([this, path]() { decodeLoop(path); });
 	return true;
 }
 
 void VideoPlayer::stop() {
-	m_threadRunning = false;
+	m_generation.fetch_add(1, std::memory_order_acq_rel);
+	m_threadRunning.store(false);
 	if (m_thread.joinable()) m_thread.join();
 
 	closeDecoder();