Fix: For critical exclusive mode work, disconnect secondary monitors or set them to the same refresh rate. Historically, exclusive mode was the gold standard. However, Microsoft has been pushing DXGI Flip Model and Borderless Windowed Optimizations . In Windows 11 22H2 and later, a well-coded borderless window can achieve near-exclusive latency.
Fix: Implement a WM_ACTIVATEAPP handler (Win32) that forces ResetViewport() and re-issues the exclusive command when the window regains focus. If your viewerframe is on Monitor A (144Hz) and Monitor B (60Hz) has a video playing, the DWM may force shared mode on both to sync composition timing. viewerframe mode exclusive
Fix: Ensure your rendering resolution matches the screen's native resolution exactly (e.g., 1920x1080 on a 1920x1080 panel). When you alt+tab from an exclusive viewerframe, the GPU must tear down the exclusive context and rebuild the DWM surface. This causes a 1-3 second "black flash." That is normal. However, some engines fail to reacquire exclusive mode on return. Fix: For critical exclusive mode work, disconnect secondary
How does exclusive mode interact with a viewerframe? In Windows 11 22H2 and later, a well-coded
Typically, a standard application has a main frame (the window) and a viewer (the rendering region). In shared mode, you can resize the viewerframe, drag it, or overlay UI on top of it.
To force classic exclusive mode: