While the focus change happens, Windows appears to reset the cursor clip rectangle, and then restore it if the application that has focus has the clip rectangle set.
This fixes resetting the clip rectangle while changing focus between windows in the same application, e.g. the Source 2 editor.
Alter the video driver grab/confinement function signatures to return an int, set and return an error if the grab request fails, and clear the grab flags from the window if the mouse and/or keyboard wasn't actually grabbed.
This better reflects how HDR content is actually used, e.g. most content is in the SDR range, with specular highlights and bright details beyond the SDR range, in the HDR headroom.
This more closely matches how HDR is handled on Apple platforms, as EDR.
This also greatly simplifies application code which no longer has to think about color scaling. SDR content is rendered at the appropriate brightness automatically, and HDR content is scaled to the correct range for the display HDR headroom.
When an app makes a fullscreen window on Windows, the window is really just resized to the monitor dimensions and positioned at 0, 0 and positioned on top of everything, including the taskbar. Added disabling rounded corners and some new DWM controlled border color (which seems to be defaulted to 1px transparent, but can be set to the theme color by users). Previous settings are restored when exiting fullscreen mode.
We don't need to use the hack of setting a timer and waiting for a timer message, MsgWaitForMultipleObjects() will allow us to wait for input directly with a timeout.
Before this change, sleeping for 20 ms would actually sleep for around 30 ms, with this change the sleep time is pretty accurate at 20-21 ms.
Windows doesn't inform applications if the window is in the docked/tiled state, so let windows manage the window size when restoring from a fixed-size state, unless the application explicitly requested a new size/position.
Fixes the video_getSetWindowState test.
WM_WINDOWPOSCHANGING needs to return 0 when a resize was initiated programmatically
Checking the SWP_NOMOVE and SWP_NOSIZE flags in the WINDOWPOS struct when handling WM_WINDOWPOSCHANGED to avoid sending redundant resize and move events is unreliable, as they can be set even when the window has moved or changed size, such as when leaving fullscreen, or programmatically resizing a window without STYLE_RESIZABLE set.
Fixes the video_getSetWindowSize and video_setWindowCenteredOnDisplay tests.
Applications might override WM_WINDOWPOSCHANGING which would prevent us from getting the correct window state.
This also fixes cases where the window doesn't get WM_SHOWWINDOW, as described in Raymond Chen's blog post:
https://devblogs.microsoft.com/oldnewthing/20080115-00/?p=23813
It turns out that when you enable raw input and then process Windows messages, you'll get the currently pending input in GetRawInputBuffer(), and you'll get any new input that occurs while processing messages as WM_INPUT.
The fix for this is to create a dedicated thread to handle raw input and only use GetRawInputBuffer() in that thread. A nice side effect of this is that we'll get mouse input at the lowest latency possible, but raw mouse events will now occur on a separate thread, outside of the normal event loop processing.
Improved fix for https://github.com/libsdl-org/SDL/issues/8756
