[feat] add HarmonyOS desktop and mobile clients，issue #117

apps/harmony/native/capture_surface.h

@@ -0,0 +1,37 @@
+/*
+ * @Author: DI JUNKUN
+ * @Date: 2026-10-15
+ * Copyright (c) 2026 by DI JUNKUN, All Rights Reserved.
+ */
+
+#ifndef _CAPTURE_SURFACE_H_
+#define _CAPTURE_SURFACE_H_
+
+#include <condition_variable>
+#include <cstdint>
+#include <functional>
+#include <mutex>
+#include <thread>
+#include <native_image/native_image.h>
+
+namespace crossdesk::harmony {
+// Owns the capture texture and its EGL context on one worker. Some graphics
+// drivers expose GPU-backed capture buffers that cannot be read via mmap.
+class CaptureSurface {
+ public:
+  using Frame = std::function<void(const uint8_t*, int, int, int)>;
+  ~CaptureSurface() { Stop(); }
+  OHNativeWindow* Start(int width, int height, Frame frame);
+  void Stop();
+ private:
+  void Run(int width, int height, Frame frame);
+  std::mutex mutex_;
+  std::condition_variable ready_;
+  bool prepared_ = false, stopping_ = true;
+  unsigned pending_ = 0;
+  OHNativeWindow* window_ = nullptr; // Owned by the worker's OH_NativeImage.
+  std::thread thread_;
+};
+}
+
+#endif