[dxgi] Pass display refresh in windowed mode if latency sleep is enabled

src/dxgi/dxgi_swapchain.cpp

@@ -43,6 +43,14 @@ namespace dxvk {
 
     // Ensure that RGBA16 swap chains are scRGB if supported
     UpdateColorSpace(m_desc.Format, m_colorSpace);
+
+    // Somewhat hacky way to determine whether to forward the
+    // display refresh rate in windowed mode even with a sync
+    // interval of 1.
+    if (!m_is_d3d12) {
+      auto instance = pFactory->GetDXVKInstance();
+      m_hasLatencyControl = instance->options().latencySleep == Tristate::True;
+    }
   }
   
   
@@ -1000,10 +1008,12 @@ namespace dxvk {
     // Engage the frame limiter with large sync intervals even in windowed
     // mode since we want to avoid double-presenting to the swap chain.
     if (SyncInterval != m_frameRateSyncInterval && m_descFs.Windowed) {
+      bool engageLimiter = (SyncInterval > 1u) || (SyncInterval && m_hasLatencyControl);
+
       m_frameRateSyncInterval = SyncInterval;
       m_frameRateRefresh = 0.0f;
 
-      if (SyncInterval > 1 && wsi::isWindow(m_window)) {
+      if (engageLimiter && wsi::isWindow(m_window)) {
         wsi::WsiMode mode = { };
 
         if (wsi::getCurrentDisplayMode(wsi::getWindowMonitor(m_window), &mode)) {

src/dxgi/dxgi_swapchain.h

@@ -205,6 +205,7 @@ namespace dxvk {
     DXGI_COLOR_SPACE_TYPE           m_colorSpace = DXGI_COLOR_SPACE_RGB_FULL_G22_NONE_P709;
 
     uint32_t                        m_globalHDRStateSerial = 0;
+    bool                            m_hasLatencyControl = false;
     
     HRESULT EnterFullscreenMode(
             IDXGIOutput1            *pTarget);