Use a high priority dispatch queue for GCKeyboard and GCMouse events for the lowest latency possible
This appears to reduce latency between 1-4 ms on an iPad Pro.
diff --git a/src/video/uikit/SDL_uikitevents.m b/src/video/uikit/SDL_uikitevents.m
index 8206d74..06cb4f1 100644
--- a/src/video/uikit/SDL_uikitevents.m
+++ b/src/video/uikit/SDL_uikitevents.m
@@ -90,6 +90,10 @@
{
SDL_SendKeyboardKey(pressed ? SDL_PRESSED : SDL_RELEASED, (SDL_Scancode)keyCode);
};
+
+ dispatch_queue_t queue = dispatch_queue_create( "org.libsdl.input.keyboard", DISPATCH_QUEUE_SERIAL );
+ dispatch_set_target_queue( queue, dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_HIGH, 0 ) );
+ keyboard.handlerQueue = queue;
}
static void OnGCKeyboardDisconnected(GCKeyboard *keyboard) API_AVAILABLE(macos(11.0), ios(14.0), tvos(14.0))
@@ -221,6 +225,10 @@
SDL_SendMouseMotion(SDL_GetMouseFocus(), mouseID, SDL_TRUE, (int)deltaX, -(int)deltaY);
};
+ dispatch_queue_t queue = dispatch_queue_create( "org.libsdl.input.mouse", DISPATCH_QUEUE_SERIAL );
+ dispatch_set_target_queue( queue, dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_HIGH, 0 ) );
+ mouse.handlerQueue = queue;
+
++mice_connected;
}
@@ -279,7 +287,7 @@
void SDL_QuitGCMouse(void)
{
@autoreleasepool {
- if (@available(iOS 14.0, tvOS 14.0, *)) {
+ if (@available(iOS 14.1, tvOS 14.1, *)) {
NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
if (mouse_connect_observer) {
