Implement universal translation of touch to mouse

Now generating mouse events from touch is optional (on by default) and it's performed by `InputDefault` instead of having each OS abstraction doing it. (*)

The translation algorithm waits for a touch index to be pressed and tracks it translating its events to mouse events until it is raised, while ignoring other pointers.

Furthermore, to avoid an stuck "touch mouse", since not all platforms may report touches raised when the window is unfocused, it checks if touches are still down by the time it's focused again and if so it resets the state of the emulated mouse.

*: In the case of Windows, since it already provides touch-to-mouse translation by itself, "echo" mouse events are filtered out to have it working like the rest.

On X11 a little hack has been needed to avoid a case of a spurious mouse motion event that is generated during touch interaction.

Plus: Improve/fix tracking of current mouse position.

** Summary of changes to settings: **

- `display/window/handheld/emulate_touchscreen` becomes `input/pointing_devices/emulate_touch_from_mouse`
- New setting: `input/pointing_devices/emulate_mouse_from_touch`

1 files changed, 15 insertions, 24 deletions

diff --git a/platform/windows/os_windows.cpp b/platform/windows/os_windows.cpp
index 9c37b65d77..363f54fc7b 100644
--- a/platform/windows/os_windows.cpp
+++ b/platform/windows/os_windows.cpp
@@ -342,6 +342,14 @@ LRESULT OS_Windows::WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 		} break;
 		case WM_MOUSEMOVE: {
 
+			if (input->is_emulating_mouse_from_touch()) {
+				// Universal translation enabled; ignore OS translation
+				LPARAM extra = GetMessageExtraInfo();
+				if (IsPenEvent(extra)) {
+					break;
+				}
+			}
+
 			if (outside) {
 				//mouse enter
 
@@ -367,18 +375,6 @@ LRESULT OS_Windows::WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 			// Don't calculate relative mouse movement if we don't have focus in CAPTURED mode.
 			if (!window_has_focus && mouse_mode == MOUSE_MODE_CAPTURED)
 				break;
-			/*
-			LPARAM extra = GetMessageExtraInfo();
-			if (IsPenEvent(extra)) {
-
-				int idx = extra & 0x7f;
-				_drag_event(idx, uMsg, wParam, lParam);
-				if (idx != 0) {
-					return 0;
-				};
-				// fallthrough for mouse event
-			};
-			*/
 
 			Ref<InputEventMouseMotion> mm;
 			mm.instance();
@@ -448,18 +444,13 @@ LRESULT OS_Windows::WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 			/*case WM_XBUTTONDOWN:
 		case WM_XBUTTONUP: */ {
 
-				/*
-			LPARAM extra = GetMessageExtraInfo();
-			if (IsPenEvent(extra)) {
-
-				int idx = extra & 0x7f;
-				_touch_event(idx, uMsg, wParam, lParam);
-				if (idx != 0) {
-					return 0;
-				};
-				// fallthrough for mouse event
-			};
-			*/
+				if (input->is_emulating_mouse_from_touch()) {
+					// Universal translation enabled; ignore OS translation
+					LPARAM extra = GetMessageExtraInfo();
+					if (IsPenEvent(extra)) {
+						break;
+					}
+				}
 
 				Ref<InputEventMouseButton> mb;
 				mb.instance();