Dominik Reichardt
Exult (http://exult.info) has an editor app that uses GTK+2. Up to now we were using X's drag'n'drop to allow dropping of assets from the editor onto Exult.
There is now an experimental branch that makes use of SDL_DROPFILE. That works under X, dropping in Exult's SDL2 window puts the asset right at the spot you dropped at.
On macOS with native Exult and Quartz GTK+2 this doesn't work, the location of the drop is where the mouse was last tracked before you left the window (usually one of the edges, unless you tabbed out).
All we tried out pointed to the fact that the location update needs to be done by the dropfile event in SDL2, not by our own (which always only worked after the Exult window getting focus).
This patch adds this to SDL_cocoawindow.m and it works perfectly, passing the correct coordinates to our code (SDL_GetMouseState()).
- explicitly use UNICODE versions of DrawText, EnumDisplaySettings,
EnumDisplayDevices, and CreateDC: the underlying structures have
WCHAR strings.
- change WIN_UpdateDisplayMode and WIN_GetDisplayMode() to accept
LPCWSTR instead of LPCTSTR for the same reason.
- change WIN_StringToUTF8 and WIN_UTF8ToString to the explicit 'W'
versions where appropriate.
i.e. where the string is known guaranteed to be WCHAR*, in:
- SDL_dinputjoystick.c (WIN_IsXInputDevice): VARIANT->var is BSTR (WCHAR*)
- SDL_rawinputjoystick.c (RAWINPUT_AddDevice): string is WCHAR*
- SDL_windows_gaming_input.c (IEventHandler_CRawGameControllerVtbl_InvokeAdded):
string is WCHAR*
There should be more of these..
_InterlockedExchange_rel() is required for correctness on ARM because
the _ReadWriteBarrier() macro is only a compiler memory barrier, not a
hardware memory barrier. Due to ARM's relaxed memory model, this means
the '*lock = 0' write may be observed before the operations inside the
lock, causing possible corruption of data protected by the lock.
_InterlockedExchange_acq() is more efficient on ARM because it avoids an
expensive full memory barrier that _InterlockedExchange() does.
C.W. Betts
I tested building commit http://hg.libsdl.org/SDL/rev/7adf3fdc19f3 on Mac Catalyst and found some issues:
* MTLFeatureSet_iOS_* enums aren't available under Mac Catalyst.
* OpenGL ES is unavailable under Mac Catalyst.
* Some Metal features are available under Catalyst but not iOS, such as displaySyncEnabled.
* Set Metal as the default renderer on Mac Catalyst
Attaching a patch that will make SDL2 build for Mac Catalyst.
This is unsafe because the event is auto-reset, therefore the call to
WaitForSingleObject() resets the event which GetOverlappedResult() will
try to wait on.
Even though the overlapped operation is guaranteed to be completed at
the point we call GetOverlappedResult(), it will still wait on the event
handle for a short time to trigger the reset for auto-reset events. This
amounts to roughly a 100 ms sleep each time GetOverlappedResult() is called
for a completed I/O with a non-signalled event.
In the context of HIDAPI, this extra sleep means that callers that loop
on hid_read_timeout() with timeout=0 will loop forever, since the 100 ms
sleep each iteration ensures ReadFile() will always have new data.