[idd] capture: add forced indirect copy

doc/idd_configuration.rst

@@ -71,6 +71,13 @@ Force full direct frame copies
    disabled unless you encounter corruption. Changing it requests a driver
    reload.
 
+Force indirect copy
+   Disables direct D3D12 access to the shared transport heap and instead
+   copies each frame through a CPU-mapped readback resource. Enable this only
+   to work around a GPU driver that corrupts direct transport writes: it adds
+   a CPU copy and significantly reduces throughput. It takes precedence over
+   the direct-copy preference and requests a driver reload when changed.
+
 Unlike mode-list edits, preference checkboxes are saved when clicked.
 
 Software processing

idd/LGIdd/config/CSettings.h

@@ -101,6 +101,11 @@ class CSettings
       return ReadBoolValue(L"ForceFullDirectCopy");
     }
 
+    static bool ShouldForceIndirectCopy()
+    {
+      return ReadBoolValue(L"ForceIndirectCopy");
+    }
+
   private:
     static const wchar_t * RegistryKey()
     {

idd/LGIdd/d3d/CD3D12Device.cpp

@@ -19,6 +19,7 @@
  */
 
 #include "d3d/CD3D12Device.h"
+#include "config/CSettings.h"
 #include "CDebug.h"
 
 bool CD3D12Device::s_directHeapFailed = false;
@@ -66,8 +67,12 @@ CD3D12Device::InitResult CD3D12Device::Init(
 {
   HRESULT hr;
 
+  const bool forceIndirectCopy = CSettings::ShouldForceIndirectCopy();
   m_computeEnabled = enableCompute;
-  m_indirectCopy   = !directMemory || s_directHeapFailed;
+  m_indirectCopy   = !directMemory || s_directHeapFailed || forceIndirectCopy;
+
+  if (forceIndirectCopy)
+    DEBUG_INFO("Forcing indirect transport copies");
 
   hr = CreateDXGIFactory2(m_debug ? DXGI_CREATE_FACTORY_DEBUG : 0, IID_PPV_ARGS(&m_factory));  
   if (FAILED(hr))

idd/LGIddHelper/CConfigWindow.cpp

@@ -55,6 +55,7 @@ CConfigWindow::CConfigWindow() : m_scale(1)
     m_noGPU = m_settings.getNoGPU();
     m_exclusive = m_settings.getExclusiveMonitor();
     m_forceFullDirectCopy = m_settings.getForceFullDirectCopy();
+    m_forceIndirectCopy = m_settings.getForceIndirectCopy();
   }
 
   if (!CreateWindowEx(0, MAKEINTATOM(s_atom), L"Looking Glass IDD Configuration",
@@ -96,6 +97,7 @@ void CConfigWindow::updateFont()
     *m_defRefreshLabel, *m_defRefresh, *m_defRefreshHz, *m_modeSave, *m_modeRevert,
     *m_prefGroup, *m_prefNoGPU, *m_prefExclusive,
     *m_prefForceFullDirectCopy,
+    *m_prefForceIndirectCopy,
   }))
     SendMessage(child, WM_SETFONT, (WPARAM)m_font.Get(), 1);
 }
@@ -191,6 +193,8 @@ LRESULT CConfigWindow::onCreate()
   m_prefExclusive.reset(new CCheckbox(L"Make LG the only monitor", 0, m_hwnd));
   m_prefForceFullDirectCopy.reset(new CCheckbox(
     L"Force full direct frame copies", 0, m_hwnd));
+  m_prefForceIndirectCopy.reset(new CCheckbox(
+    L"Force indirect copy", 0, m_hwnd));
 
   if (m_noGPU)
     m_prefNoGPU->setChecked(*m_noGPU);
@@ -201,6 +205,9 @@ LRESULT CConfigWindow::onCreate()
   if (m_forceFullDirectCopy)
     m_prefForceFullDirectCopy->setChecked(*m_forceFullDirectCopy);
 
+  if (m_forceIndirectCopy)
+    m_prefForceIndirectCopy->setChecked(*m_forceIndirectCopy);
+
   LONG width, height;
   getMinimumSize(width, height);
   SetWindowPos(m_hwnd, NULL, 0, 0, width, height, SWP_NOMOVE | SWP_NOZORDER);
@@ -240,10 +247,11 @@ LRESULT CConfigWindow::onResize(DWORD width, DWORD height)
   pos.pinBottomLeft(*m_modeSave, 20, 20, 132, 24);
   pos.pinBottomLeft(*m_modeRevert, 154, 20, 50, 24);
 
-  pos.pinTopLeft(*m_prefGroup, 224, 40, 200, 92);
+  pos.pinTopLeft(*m_prefGroup, 224, 40, 200, 112);
   pos.pinTopLeft(*m_prefNoGPU, 236, 64, 176, 20);
   pos.pinTopLeft(*m_prefExclusive, 236, 84, 176, 20);
   pos.pinTopLeft(*m_prefForceFullDirectCopy, 236, 104, 188, 20);
+  pos.pinTopLeft(*m_prefForceIndirectCopy, 236, 124, 188, 20);
   return 0;
 }
 
@@ -368,6 +376,22 @@ LRESULT CConfigWindow::onCommand(WORD id, WORD code, HWND hwnd)
     m_prefForceFullDirectCopy->setChecked(value);
     sendSettingChange();
   }
+  else if (m_prefForceIndirectCopy &&
+           hwnd == *m_prefForceIndirectCopy && code == BN_CLICKED &&
+           m_forceIndirectCopy)
+  {
+    const bool value = !*m_forceIndirectCopy;
+    const LSTATUS result = m_settings.setForceIndirectCopy(value);
+    if (result != ERROR_SUCCESS)
+    {
+      DEBUG_ERROR_HR(result, "Failed to save ForceIndirectCopy");
+      return 0;
+    }
+
+    *m_forceIndirectCopy = value;
+    m_prefForceIndirectCopy->setChecked(value);
+    sendSettingChange();
+  }
   else if (m_modeSave && hwnd == *m_modeSave && code == BN_CLICKED)
   {
     bool updated = false;

idd/LGIddHelper/CConfigWindow.h

@@ -65,6 +65,7 @@ class CConfigWindow : public CWindow
   std::unique_ptr<CCheckbox> m_prefNoGPU;
   std::unique_ptr<CCheckbox> m_prefExclusive;
   std::unique_ptr<CCheckbox> m_prefForceFullDirectCopy;
+  std::unique_ptr<CCheckbox> m_prefForceIndirectCopy;
 
   std::function<void()> m_onDestroy;
   std::function<void()> m_onSettingChange;
@@ -77,6 +78,7 @@ class CConfigWindow : public CWindow
   std::optional<bool> m_noGPU;
   std::optional<bool> m_exclusive;
   std::optional<bool> m_forceFullDirectCopy;
+  std::optional<bool> m_forceIndirectCopy;
 
   void getMinimumSize(LONG &width, LONG &height);
   void updateFont();

idd/LGIddHelper/CRegistrySettings.cpp

@@ -290,3 +290,28 @@ LSTATUS CRegistrySettings::setForceFullDirectCopy(bool forceFullCopy)
   return RegSetValueEx(hKey, L"ForceFullDirectCopy", 0, REG_DWORD,
     (LPBYTE)&dwValue, sizeof(DWORD));
 }
+
+std::optional<bool> CRegistrySettings::getForceIndirectCopy()
+{
+  DWORD result, cbData = sizeof result;
+
+  LSTATUS status = RegGetValue(hKey, nullptr, L"ForceIndirectCopy",
+    RRF_RT_REG_DWORD, nullptr, &result, &cbData);
+  switch (status)
+  {
+  case ERROR_SUCCESS:
+    return !!result;
+  case ERROR_FILE_NOT_FOUND:
+    return false;
+  default:
+    DEBUG_ERROR_HR(status, "RegGetValue(ForceIndirectCopy)");
+    return {};
+  }
+}
+
+LSTATUS CRegistrySettings::setForceIndirectCopy(bool forceIndirectCopy)
+{
+  DWORD dwValue = forceIndirectCopy;
+  return RegSetValueEx(hKey, L"ForceIndirectCopy", 0, REG_DWORD,
+    (LPBYTE)&dwValue, sizeof(DWORD));
+}

idd/LGIddHelper/CRegistrySettings.h

@@ -59,4 +59,7 @@ public:
 
   std::optional<bool> getForceFullDirectCopy();
   LSTATUS setForceFullDirectCopy(bool forceFullCopy);
+
+  std::optional<bool> getForceIndirectCopy();
+  LSTATUS setForceIndirectCopy(bool forceIndirectCopy);
 };