iOS: Pass through touches near the task switcher only in-game. Makes the UI better behaved.

Common/System/System.h

@@ -229,6 +229,7 @@ enum class SystemNotification {
 	TEST_JAVA_EXCEPTION,
 	KEEP_SCREEN_AWAKE,
 	ACTIVITY,
+	UI_STATE_CHANGED,
 };
 
 // I guess it's not super great architecturally to centralize this, since it's not general - but same with a lot of

Core/System.cpp

@@ -128,6 +128,7 @@ void UpdateUIState(GlobalUIState newState) {
 	if (globalUIState != newState && globalUIState != UISTATE_EXIT) {
 		globalUIState = newState;
 		System_Notify(SystemNotification::DISASSEMBLY);
+		System_Notify(SystemNotification::UI_STATE_CHANGED);
 		System_SetKeepScreenBright(globalUIState == UISTATE_INGAME);
 	}
 }

ios/ViewController.mm

@@ -392,7 +392,22 @@ void GLRenderLoop(IOSGLESContext *graphicsContext) {
 // Enables tapping for edge area.
 -(UIRectEdge)preferredScreenEdgesDeferringSystemGestures
 {
-	return UIRectEdgeAll;
+	if (GetUIState() == UISTATE_INGAME) {
+		// In-game, we need all the control we can get. Though, we could possibly
+		// allow the top edge?
+		INFO_LOG(SYSTEM, "Defer system gestures on all edges");
+		return UIRectEdgeAll;
+	} else {
+		INFO_LOG(SYSTEM, "Allow system gestures on the bottom");
+		// Allow task switching gestures to take precedence, without causing
+		// scroll events in the UI.
+		return UIRectEdgeTop | UIRectEdgeLeft | UIRectEdgeRight;
+	}
+}
+
+- (void)uiStateChanged
+{
+	[self setNeedsUpdateOfScreenEdgesDeferringSystemGestures];
 }
 
 - (UIView *)getView {

ios/ViewControllerCommon.h

@@ -20,6 +20,8 @@
 - (void)didBecomeActive;
 - (void)willResignActive;
 
+- (void)uiStateChanged;
+
 @end
 
 extern id <PPSSPPViewController> sharedViewController;

ios/ViewControllerMetal.mm

@@ -477,7 +477,22 @@ extern float g_safeInsetBottom;
 // Enables tapping for edge area.
 -(UIRectEdge)preferredScreenEdgesDeferringSystemGestures
 {
-	return UIRectEdgeAll;
+	if (GetUIState() == UISTATE_INGAME) {
+		// In-game, we need all the control we can get. Though, we could possibly
+		// allow the top edge?
+		INFO_LOG(SYSTEM, "Defer system gestures on all edges");
+		return UIRectEdgeAll;
+	} else {
+		INFO_LOG(SYSTEM, "Allow system gestures on the bottom");
+		// Allow task switching gestures to take precedence, without causing
+		// scroll events in the UI.
+		return UIRectEdgeTop | UIRectEdgeLeft | UIRectEdgeRight;
+	}
+}
+
+- (void)uiStateChanged
+{
+	[self setNeedsUpdateOfScreenEdgesDeferringSystemGestures];
 }
 
 - (void)bindDefaultFBO

ios/main.mm

@@ -386,7 +386,15 @@ bool System_GetPropertyBool(SystemProperty prop) {
 
 void System_Notify(SystemNotification notification) {
 	switch (notification) {
-	default: break;
+	case SystemNotification::UI_STATE_CHANGED:
+		dispatch_async(dispatch_get_main_queue(), ^{
+			if (sharedViewController) {
+				[sharedViewController uiStateChanged];
+			}
+		});
+		break;
+	default:
+		break;
 	}
 }