implement cgutmans ideas

src/platform/windows/display_base.cpp

@@ -6,6 +6,7 @@
 #include <initguid.h>
 #include <thread>
 
+#include <boost/algorithm/string/join.hpp>
 #include <boost/process.hpp>
 
 // We have to include boost/process.hpp before display.h due to WinSock.h,
@@ -363,8 +364,10 @@ namespace platf::dxgi {
   // we spawn a helper tool to probe for us before we set our own GPU preference.
   bool
   probe_for_gpu_preference(const std::string &display_name) {
-    // If we've already been through here, there's nothing to do this time.
     static bool set_gpu_preference = false;
+    static bool verify_frame_capture = true;
+
+    // If we've already been through here, there's nothing to do this time.
     if (set_gpu_preference) {
       return true;
     }
@@ -378,17 +381,22 @@ namespace platf::dxgi {
     for (int i = 1; i < 5; i++) {
       // Run the probe tool. It returns the status of DuplicateOutput().
       //
-      // Arg format: [GPU preference] [Display name]
+      // Arg format: [GPU preference] [Display name] [--verify--frame-capture]
       HRESULT result;
+      std::vector<std::string> args = { std::to_string(i), display_name };
       try {
-        result = bp::system(cmd, std::to_string(i), display_name, bp::std_out > bp::null, bp::std_err > bp::null);
+        if (verify_frame_capture) {
+          args.push_back("--verify-frame-capture");
+        }
+        result = bp::system(cmd, bp::args(args), bp::std_out > bp::null, bp::std_err > bp::null);
       }
       catch (bp::process_error &e) {
         BOOST_LOG(error) << "Failed to start ddprobe.exe: "sv << e.what();
         return false;
       }
 
-      BOOST_LOG(info) << "ddprobe.exe ["sv << i << "] ["sv << display_name << "] returned: 0x"sv << util::hex(result).to_string_view();
+      BOOST_LOG(info) << "ddprobe.exe " << boost::algorithm::join(args, " ") << "returned 0x"
+                      << util::hex(result).to_string_view();
 
       // E_ACCESSDENIED can happen at the login screen. If we get this error,
       // we know capture would have been supported, because DXGI_ERROR_UNSUPPORTED
@@ -410,6 +418,8 @@ namespace platf::dxgi {
     }
 
     // If none of the manual options worked, leave the GPU preference alone
+    // And set the verify frame capture option to false, just in case there is a chance for a false negative.
+    verify_frame_capture = false;
     return false;
   }
 

tools/ddprobe.cpp

@@ -121,7 +121,7 @@ is_valid_frame(const D3D11_MAPPED_SUBRESOURCE &mappedResource, const D3D11_TEXTU
  *
  * @param dup A reference to the DXGI output duplication object (`dxgi::dup_t&`) used to acquire frames.
  * @param device A ComPtr to the ID3D11Device interface representing the device associated with the Direct3D context.
- * @return HRESULT Returns `S_OK` if a non-empty frame is captured successfully, `S_FALSE` if all frames are empty, or an error code if any failure occurs during the process.
+ * @return HRESULT Returns `S_OK` if a non-empty frame is captured successfully, `E_FAIL` if all frames are empty, or an error code if any failure occurs during the process.
  */
 HRESULT
 test_frame_capture(dxgi::dup_t &dup, ComPtr<ID3D11Device> device) {
@@ -188,11 +188,11 @@ test_frame_capture(dxgi::dup_t &dup, ComPtr<ID3D11Device> device) {
   }
 
   // All frames were empty, indicating potential capture issues.
-  return S_FALSE;
+  return E_FAIL;
 }
 
 HRESULT
-test_dxgi_duplication(dxgi::adapter_t &adapter, dxgi::output_t &output) {
+test_dxgi_duplication(dxgi::adapter_t &adapter, dxgi::output_t &output, bool verify_frame_capture) {
   D3D_FEATURE_LEVEL featureLevels[] {
     D3D_FEATURE_LEVEL_11_1,
     D3D_FEATURE_LEVEL_11_0,
@@ -239,13 +239,16 @@ test_dxgi_duplication(dxgi::adapter_t &adapter, dxgi::output_t &output) {
     return result;
   }
 
-  // If duplication is successful, test frame capture
-  HRESULT captureResult = test_frame_capture(dup, device_ptr.Get());
-  if (FAILED(captureResult)) {
-    std::cout << "Frame capture test failed [0x"sv << util::hex(captureResult).to_string_view() << "]" << std::endl;
-    return captureResult;
+  // To prevent false negatives, we'll make it optional to test for frame capture.
+  if (verify_frame_capture) {
+    HRESULT captureResult = test_frame_capture(dup, device_ptr.Get());
+    if (FAILED(captureResult)) {
+      std::cout << "Frame capture test failed [0x"sv << util::hex(captureResult).to_string_view() << "]" << std::endl;
+      return captureResult;
+    }
   }
 
+
   return S_OK;
 }
 
@@ -253,20 +256,34 @@ int
 main(int argc, char *argv[]) {
   HRESULT status;
 
-  // Display name may be omitted
-  if (argc != 2 && argc != 3) {
-    std::cout << "ddprobe.exe [GPU preference value] [display name]"sv << std::endl;
+  // Usage message
+  if (argc < 2 || argc > 4) {
+    std::cout << "Usage: ddprobe.exe [GPU preference value] [display name] [--verify-frame-capture]"sv << std::endl;
     return -1;
   }
 
   std::wstring display_name;
-  if (argc == 3) {
-    std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>, wchar_t> converter;
-    display_name = converter.from_bytes(argv[2]);
+  bool verify_frame_capture = false;
+
+  // Parse GPU preference value (required)
+  int gpu_preference = atoi(argv[1]);
+
+  // Parse optional arguments
+  for (int i = 2; i < argc; ++i) {
+    std::string arg = argv[i];
+
+    if (arg == "--verify-frame-capture") {
+      verify_frame_capture = true;
+    }
+    else {
+      // Assume any other argument is the display name
+      std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>, wchar_t> converter;
+      display_name = converter.from_bytes(arg);
+    }
   }
 
   // We must set the GPU preference before making any DXGI/D3D calls
-  status = set_gpu_preference(atoi(argv[1]));
+  status = set_gpu_preference(gpu_preference);
   if (status != ERROR_SUCCESS) {
     return status;
   }
@@ -310,7 +327,7 @@ main(int argc, char *argv[]) {
       }
 
       // We found the matching output. Test it and return the result.
-      return test_dxgi_duplication(adapter, output);
+      return test_dxgi_duplication(adapter, output, verify_frame_capture);
     }
   }