[fix] resolve failures in the WGC→DXGI→GDI fallback chain

src/screen_capturer/windows/screen_capturer_wgc.cpp

@@ -56,8 +56,6 @@ BOOL WINAPI EnumMonitorProc(HMONITOR hmonitor, [[maybe_unused]] HDC hdc,
     }
   }
 
-  if (monitor_info_.dwFlags == DISPLAY_DEVICE_MIRRORING_DRIVER) return true;
-
   return true;
 }
 
@@ -165,6 +163,8 @@ int ScreenCapturerWgc::Start(bool show_cursor) {
     return 4;
   }
 
+  bool any_started = false;
+  int last_error = 0;
   for (int i = 0; i < sessions_.size(); i++) {
     if (sessions_[i].inited_ == false) {
       LOG_ERROR("Session {} not inited", i);
@@ -174,17 +174,27 @@ int ScreenCapturerWgc::Start(bool show_cursor) {
     if (sessions_[i].running_) {
       LOG_ERROR("Session {} is already running", i);
     } else {
-      sessions_[i].session_->Start(show_cursor);
+      int ret = sessions_[i].session_->Start(show_cursor);
+      if (ret != 0) {
+        LOG_ERROR("Session {} start failed, ret={}", i, ret);
+        last_error = ret;
+        continue;
+      }
 
       if (i != 0) {
         sessions_[i].session_->Pause();
         sessions_[i].paused_ = true;
       }
       sessions_[i].running_ = true;
+      any_started = true;
     }
-    running_ = true;
+    running_ = running_ || any_started;
   }
 
+  if (!any_started) {
+    LOG_ERROR("WGC: no session started successfully");
+    return last_error != 0 ? last_error : -1;
+  }
   return 0;
 }
 

src/screen_capturer/windows/screen_capturer_wgc.h

@@ -57,8 +57,8 @@ class ScreenCapturerWgc : public ScreenCapturer,
 
   std::vector<WgcSessionInfo> sessions_;
 
-  std::atomic_bool running_;
-  std::atomic_bool inited_;
+  std::atomic_bool running_{false};
+  std::atomic_bool inited_{false};
 
   int fps_ = 60;
 

src/screen_capturer/windows/screen_capturer_win.cpp

@@ -1,6 +1,9 @@
 #include "screen_capturer_win.h"
 
+#include <cmath>
 #include <memory>
+#include <string>
+#include <vector>
 
 #include "rd_log.h"
 #include "screen_capturer_dxgi.h"
@@ -14,7 +17,26 @@ ScreenCapturerWin::~ScreenCapturerWin() { Destroy(); }
 
 int ScreenCapturerWin::Init(const int fps, cb_desktop_data cb) {
   fps_ = fps;
-  cb_ = cb;
+  cb_orig_ = cb;
+  cb_ = [this](unsigned char* data, int size, int w, int h,
+               const char* display_name) {
+    std::string mapped_name;
+    {
+      std::lock_guard<std::mutex> lock(alias_mutex_);
+      auto it = label_alias_.find(display_name);
+      if (it != label_alias_.end())
+        mapped_name = it->second;
+      else
+        mapped_name = display_name;
+    }
+    {
+      std::lock_guard<std::mutex> lock(alias_mutex_);
+      if (canonical_labels_.find(mapped_name) == canonical_labels_.end()) {
+        return;
+      }
+    }
+    if (cb_orig_) cb_orig_(data, size, w, h, mapped_name.c_str());
+  };
 
   int ret = -1;
 
@@ -22,6 +44,7 @@ int ScreenCapturerWin::Init(const int fps, cb_desktop_data cb) {
   ret = impl_->Init(fps_, cb_);
   if (ret == 0) {
     LOG_INFO("Windows capturer: using WGC");
+    BuildCanonicalFromImpl();
     return 0;
   }
 
@@ -32,6 +55,7 @@ int ScreenCapturerWin::Init(const int fps, cb_desktop_data cb) {
   ret = impl_->Init(fps_, cb_);
   if (ret == 0) {
     LOG_INFO("Windows capturer: using DXGI Desktop Duplication");
+    BuildCanonicalFromImpl();
     return 0;
   }
 
@@ -42,6 +66,7 @@ int ScreenCapturerWin::Init(const int fps, cb_desktop_data cb) {
   ret = impl_->Init(fps_, cb_);
   if (ret == 0) {
     LOG_INFO("Windows capturer: using GDI BitBlt");
+    BuildCanonicalFromImpl();
     return 0;
   }
 
@@ -55,12 +80,52 @@ int ScreenCapturerWin::Destroy() {
     impl_->Destroy();
     impl_.reset();
   }
+  {
+    std::lock_guard<std::mutex> lock(alias_mutex_);
+    label_alias_.clear();
+    handle_to_canonical_.clear();
+    canonical_labels_.clear();
+  }
   return 0;
 }
 
 int ScreenCapturerWin::Start(bool show_cursor) {
   if (!impl_) return -1;
-  return impl_->Start(show_cursor);
+  int ret = impl_->Start(show_cursor);
+  if (ret == 0) return 0;
+
+  LOG_WARN("Windows capturer: Start failed (ret={}), trying fallback", ret);
+
+  auto try_init_start = [&](std::unique_ptr<ScreenCapturer> cand) -> bool {
+    int r = cand->Init(fps_, cb_);
+    if (r != 0) return false;
+    int s = cand->Start(show_cursor);
+    if (s == 0) {
+      impl_ = std::move(cand);
+      RebuildAliasesFromImpl();
+      return true;
+    }
+    return false;
+  };
+
+  if (dynamic_cast<ScreenCapturerWgc*>(impl_.get())) {
+    if (try_init_start(std::make_unique<ScreenCapturerDxgi>())) {
+      LOG_INFO("Windows capturer: fallback to DXGI");
+      return 0;
+    }
+    if (try_init_start(std::make_unique<ScreenCapturerGdi>())) {
+      LOG_INFO("Windows capturer: fallback to GDI");
+      return 0;
+    }
+  } else if (dynamic_cast<ScreenCapturerDxgi*>(impl_.get())) {
+    if (try_init_start(std::make_unique<ScreenCapturerGdi>())) {
+      LOG_INFO("Windows capturer: fallback to GDI");
+      return 0;
+    }
+  }
+
+  LOG_ERROR("Windows capturer: all fallbacks failed to start");
+  return ret;
 }
 
 int ScreenCapturerWin::Stop() {
@@ -88,4 +153,46 @@ std::vector<DisplayInfo> ScreenCapturerWin::GetDisplayInfoList() {
   return impl_->GetDisplayInfoList();
 }
 
+void ScreenCapturerWin::BuildCanonicalFromImpl() {
+  std::lock_guard<std::mutex> lock(alias_mutex_);
+  handle_to_canonical_.clear();
+  label_alias_.clear();
+  canonical_displays_ = impl_->GetDisplayInfoList();
+  canonical_labels_.clear();
+  for (const auto& di : canonical_displays_) {
+    handle_to_canonical_[di.handle] = di.name;
+    canonical_labels_.insert(di.name);
+  }
+}
+
+void ScreenCapturerWin::RebuildAliasesFromImpl() {
+  std::lock_guard<std::mutex> lock(alias_mutex_);
+  label_alias_.clear();
+  auto current = impl_->GetDisplayInfoList();
+  auto similar = [&](const DisplayInfo& a, const DisplayInfo& b) {
+    int dl = std::abs(a.left - b.left);
+    int dt = std::abs(a.top - b.top);
+    int dw = std::abs(a.width - b.width);
+    int dh = std::abs(a.height - b.height);
+    return dl <= 10 && dt <= 10 && dw <= 20 && dh <= 20;
+  };
+  for (const auto& di : current) {
+    std::string canonical;
+    auto it = handle_to_canonical_.find(di.handle);
+    if (it != handle_to_canonical_.end()) {
+      canonical = it->second;
+    } else {
+      for (const auto& c : canonical_displays_) {
+        if (similar(di, c) || (di.is_primary && c.is_primary)) {
+          canonical = c.name;
+          break;
+        }
+      }
+    }
+    if (!canonical.empty() && canonical != di.name) {
+      label_alias_[di.name] = canonical;
+    }
+  }
+}
+
 }  // namespace crossdesk

src/screen_capturer/windows/screen_capturer_win.h

@@ -8,6 +8,9 @@
 #define _SCREEN_CAPTURER_WIN_H_
 
 #include <memory>
+#include <mutex>
+#include <unordered_map>
+#include <unordered_set>
 #include <vector>
 
 #include "screen_capturer.h"
@@ -36,7 +39,16 @@ class ScreenCapturerWin : public ScreenCapturer {
   std::unique_ptr<ScreenCapturer> impl_;
   int fps_ = 60;
   cb_desktop_data cb_;
+  cb_desktop_data cb_orig_;
+
+  std::unordered_map<void*, std::string> handle_to_canonical_;
+  std::unordered_map<std::string, std::string> label_alias_;
+  std::mutex alias_mutex_;
+  std::vector<DisplayInfo> canonical_displays_;
+  std::unordered_set<std::string> canonical_labels_;
+
+  void BuildCanonicalFromImpl();
+  void RebuildAliasesFromImpl();
 };
 }  // namespace crossdesk
-
 #endif

src/screen_capturer/windows/wgc_session_impl.cpp

@@ -7,6 +7,8 @@
 #include <iostream>
 #include <memory>
 
+#include "rd_log.h"
+
 #define CHECK_INIT                            \
   if (!is_initialized_) {                     \
     std::cout << "AE_NEED_INIT" << std::endl; \
@@ -64,6 +66,7 @@ int WgcSessionImpl::Start(bool show_cursor) {
 
   CHECK_INIT;
   try {
+    last_show_cursor_ = show_cursor;
     if (!capture_session_) {
       auto current_size = capture_item_.Size();
       capture_framepool_ =
@@ -89,13 +92,12 @@ int WgcSessionImpl::Start(bool show_cursor) {
     // we need to test the performance later
     // loop_ = std::thread(std::bind(&WgcSessionImpl::message_func, this));
 
-    capture_session_.StartCapture();
-
     capture_session_.IsCursorCaptureEnabled(show_cursor);
+    capture_session_.StartCapture();
 
     error = 0;
   } catch (winrt::hresult_error) {
-    std::cout << "AE_WGC_CREATE_CAPTURER_FAILED" << std::endl;
+    LOG_ERROR("AE_WGC_CREATE_CAPTURER_FAILED");
     return 86;
   } catch (...) {
     return 86;
@@ -246,8 +248,15 @@ void WgcSessionImpl::OnFrame(
       auto frame_captured =
           GetDXGIInterfaceFromObject<ID3D11Texture2D>(frame.Surface());
 
-      if (!d3d11_texture_mapped_ || is_new_size)
-        CreateMappedTexture(frame_captured);
+      if (!d3d11_texture_mapped_ || is_new_size) {
+        HRESULT tex_hr = CreateMappedTexture(frame_captured);
+        if (FAILED(tex_hr)) {
+          OutputDebugStringW(
+              (L"CreateMappedTexture failed: " + std::to_wstring(tex_hr))
+                  .c_str());
+          return;
+        }
+      }
 
       d3d11_device_context_->CopyResource(d3d11_texture_mapped_.get(),
                                           frame_captured.get());
@@ -262,6 +271,7 @@ void WgcSessionImpl::OnFrame(
       if (FAILED(hr)) {
         OutputDebugStringW(
             (L"map resource failed: " + std::to_wstring(hr)).c_str());
+        return;
       }
 
       // copy data from map_result.pData
@@ -290,7 +300,24 @@ void WgcSessionImpl::OnFrame(
 void WgcSessionImpl::OnClosed(
     winrt::Windows::Graphics::Capture::GraphicsCaptureItem const&,
     winrt::Windows::Foundation::IInspectable const&) {
-  OutputDebugStringW(L"WgcSessionImpl::OnClosed");
+  std::lock_guard locker(lock_);
+  try {
+    CleanUp();
+    is_initialized_ = false;
+    if (Initialize() == 0) {
+      int ret = Start(last_show_cursor_);
+      if (ret == 0) {
+        OutputDebugStringW(L"WgcSessionImpl::OnClosed: auto recovered");
+      } else {
+        OutputDebugStringW(L"WgcSessionImpl::OnClosed: recover Start failed");
+      }
+    } else {
+      OutputDebugStringW(
+          L"WgcSessionImpl::OnClosed: recover Initialize failed");
+    }
+  } catch (...) {
+    OutputDebugStringW(L"WgcSessionImpl::OnClosed: exception during recover");
+  }
 }
 
 int WgcSessionImpl::Initialize() {
@@ -313,7 +340,7 @@ int WgcSessionImpl::Initialize() {
     d3d11_device->GetImmediateContext(d3d11_device_context_.put());
 
   } catch (winrt::hresult_error) {
-    std::cout << "AE_WGC_CREATE_CAPTURER_FAILED" << std::endl;
+    LOG_ERROR("AE_WGC_CREATE_CAPTURER_FAILED");
     return 86;
   } catch (...) {
     return 86;

src/screen_capturer/windows/wgc_session_impl.h

@@ -79,6 +79,7 @@ class WgcSessionImpl : public WgcSession {
   bool is_initialized_ = false;
   bool is_running_ = false;
   bool is_paused_ = false;
+  bool last_show_cursor_ = false;
 
   wgc_session_observer* observer_ = nullptr;