Fix Determining Window for Touchscreen

DisplayServer::screen_is_touchscreen will likely never utilize its
parameter p_screen.
This PR replaces this function by DisplayServer::is_touchscreen_available()
with the same functionality.
This solves the problem, that a SubViewport was used for determining
the screen, which resulted in error messages.

4 files changed, 6 insertions, 6 deletions

diff --git a/scene/2d/touch_screen_button.cpp b/scene/2d/touch_screen_button.cpp
index a02f322ef1..e99821e9b9 100644
--- a/scene/2d/touch_screen_button.cpp
+++ b/scene/2d/touch_screen_button.cpp
@@ -100,7 +100,7 @@ void TouchScreenButton::_notification(int p_what) {
 			if (!is_inside_tree()) {
 				return;
 			}
-			if (!Engine::get_singleton()->is_editor_hint() && !!DisplayServer::get_singleton()->screen_is_touchscreen(DisplayServer::get_singleton()->window_get_current_screen(get_viewport()->get_window_id())) && visibility == VISIBILITY_TOUCHSCREEN_ONLY) {
+			if (!Engine::get_singleton()->is_editor_hint() && !!DisplayServer::get_singleton()->is_touchscreen_available() && visibility == VISIBILITY_TOUCHSCREEN_ONLY) {
 				return;
 			}
 
@@ -137,7 +137,7 @@ void TouchScreenButton::_notification(int p_what) {
 		} break;
 
 		case NOTIFICATION_ENTER_TREE: {
-			if (!Engine::get_singleton()->is_editor_hint() && !!DisplayServer::get_singleton()->screen_is_touchscreen(DisplayServer::get_singleton()->window_get_current_screen(get_viewport()->get_window_id())) && visibility == VISIBILITY_TOUCHSCREEN_ONLY) {
+			if (!Engine::get_singleton()->is_editor_hint() && !!DisplayServer::get_singleton()->is_touchscreen_available() && visibility == VISIBILITY_TOUCHSCREEN_ONLY) {
 				return;
 			}
 			queue_redraw();
diff --git a/scene/gui/scroll_bar.cpp b/scene/gui/scroll_bar.cpp
index 6899178885..a44ddff507 100644
--- a/scene/gui/scroll_bar.cpp
+++ b/scene/gui/scroll_bar.cpp
@@ -550,7 +550,7 @@ void ScrollBar::_drag_node_input(const Ref<InputEvent> &p_input) {
 			drag_node_accum = Vector2();
 			last_drag_node_accum = Vector2();
 			drag_node_from = Vector2(orientation == HORIZONTAL ? get_value() : 0, orientation == VERTICAL ? get_value() : 0);
-			drag_node_touching = DisplayServer::get_singleton()->screen_is_touchscreen(DisplayServer::get_singleton()->window_get_current_screen(get_viewport()->get_window_id()));
+			drag_node_touching = DisplayServer::get_singleton()->is_touchscreen_available();
 			drag_node_touching_deaccel = false;
 			time_since_motion = 0;
 
diff --git a/scene/gui/scroll_container.cpp b/scene/gui/scroll_container.cpp
index 531226f938..73d30b7568 100644
--- a/scene/gui/scroll_container.cpp
+++ b/scene/gui/scroll_container.cpp
@@ -164,8 +164,8 @@ void ScrollContainer::gui_input(const Ref<InputEvent> &p_gui_input) {
 			}
 		}
 
-		bool screen_is_touchscreen = DisplayServer::get_singleton()->screen_is_touchscreen(DisplayServer::get_singleton()->window_get_current_screen(get_viewport()->get_window_id()));
-		if (!screen_is_touchscreen) {
+		bool is_touchscreen_available = DisplayServer::get_singleton()->is_touchscreen_available();
+		if (!is_touchscreen_available) {
 			return;
 		}
 
diff --git a/scene/gui/tree.cpp b/scene/gui/tree.cpp
index c0990211aa..3996d2d65d 100644
--- a/scene/gui/tree.cpp
+++ b/scene/gui/tree.cpp
@@ -3671,7 +3671,7 @@ void Tree::gui_input(const Ref<InputEvent> &p_event) {
 					drag_accum = 0;
 					//last_drag_accum=0;
 					drag_from = v_scroll->get_value();
-					drag_touching = DisplayServer::get_singleton()->screen_is_touchscreen(DisplayServer::get_singleton()->window_get_current_screen(get_viewport()->get_window_id()));
+					drag_touching = DisplayServer::get_singleton()->is_touchscreen_available();
 					drag_touching_deaccel = false;
 					if (drag_touching) {
 						set_physics_process_internal(true);