From 5a746525693d63866ef79884e25a84f687283704 Mon Sep 17 00:00:00 2001
From: Rindbee <idleman@yeah.net>
Date: Sat, 16 Jul 2022 13:23:33 +0800
Subject: [PATCH] Fix getting wrong focus neighbor when the control is in
 `ScrollContainer`
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Exclude controls inside a `ScrollContainer` that are outside the visible area of ​​
the `ScrollContainer` when looking for focus neighbors.
---
 scene/gui/control.cpp | 30 ++++++++++++++++++++++--------
 scene/gui/control.h   |  2 +-
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/scene/gui/control.cpp b/scene/gui/control.cpp
index c8318e1d9db1..e81e3c552616 100644
--- a/scene/gui/control.cpp
+++ b/scene/gui/control.cpp
@@ -35,6 +35,7 @@
 #include "core/math/geometry_2d.h"
 #include "core/os/os.h"
 #include "core/string/translation_server.h"
+#include "scene/gui/scroll_container.h"
 #include "scene/main/canvas_layer.h"
 #include "scene/main/window.h"
 #include "scene/theme/theme_db.h"
@@ -2327,7 +2328,9 @@ Control *Control::_get_focus_neighbor(Side p_side, int p_count) {
 		return nullptr;
 	}
 
-	_window_find_focus_neighbor(vdir, base, points, maxd, dist, &result);
+	Rect2 clamp = Rect2(Point2(-1e7, -1e7), Size2(2e7, 2e7));
+
+	_window_find_focus_neighbor(vdir, base, points, clamp, maxd, dist, &result);
 
 	return result;
 }
@@ -2336,14 +2339,14 @@ Control *Control::find_valid_focus_neighbor(Side p_side) const {
 	return const_cast<Control *>(this)->_get_focus_neighbor(p_side);
 }
 
-void Control::_window_find_focus_neighbor(const Vector2 &p_dir, Node *p_at, const Point2 *p_points, real_t p_min, real_t &r_closest_dist, Control **r_closest) {
+void Control::_window_find_focus_neighbor(const Vector2 &p_dir, Node *p_at, const Point2 *p_points, Rect2 &p_clamp, real_t p_min, real_t &r_closest_dist, Control **r_closest) {
 	if (Object::cast_to<Viewport>(p_at)) {
 		return; //bye
 	}
 
 	Control *c = Object::cast_to<Control>(p_at);
 
-	if (c && c != this && c->get_focus_mode() == FOCUS_ALL && c->is_visible_in_tree()) {
+	if (c && c != this && c->get_focus_mode() == FOCUS_ALL && c->is_visible_in_tree() && p_clamp.intersects(c->get_global_rect())) {
 		Point2 points[4];
 
 		Transform2D xform = c->get_global_transform();
@@ -2371,16 +2374,16 @@ void Control::_window_find_focus_neighbor(const Vector2 &p_dir, Node *p_at, cons
 			closest_center = closest_xform.xform(0.5 * closest->get_size());
 		}
 
-		real_t min = 1e7;
+		real_t max = -1e7;
 
 		for (int i = 0; i < 4; i++) {
 			real_t d = p_dir.dot(points[i]);
-			if (d < min) {
-				min = d;
+			if (d > max) {
+				max = d;
 			}
 		}
 
-		if (min > (p_min - CMP_EPSILON)) {
+		if (max > (p_min + CMP_EPSILON)) {
 			for (int i = 0; i < 4; i++) {
 				Vector2 la = p_points[i];
 				Vector2 lb = p_points[(i + 1) % 4];
@@ -2406,13 +2409,24 @@ void Control::_window_find_focus_neighbor(const Vector2 &p_dir, Node *p_at, cons
 		}
 	}
 
+	ScrollContainer *sc = Object::cast_to<ScrollContainer>(c);
+	Rect2 intersection = p_clamp;
+	if (sc) {
+		if (!sc->is_following_focus() || !sc->is_ancestor_of(this)) {
+			intersection = p_clamp.intersection(sc->get_global_rect());
+			if (!intersection.has_area()) {
+				return;
+			}
+		}
+	}
+
 	for (int i = 0; i < p_at->get_child_count(); i++) {
 		Node *child = p_at->get_child(i);
 		Control *childc = Object::cast_to<Control>(child);
 		if (childc && childc->data.RI) {
 			continue; //subwindow, ignore
 		}
-		_window_find_focus_neighbor(p_dir, p_at->get_child(i), p_points, p_min, r_closest_dist, r_closest);
+		_window_find_focus_neighbor(p_dir, p_at->get_child(i), p_points, intersection, p_min, r_closest_dist, r_closest);
 	}
 }
 
diff --git a/scene/gui/control.h b/scene/gui/control.h
index 23190381f3f4..970f5740ca67 100644
--- a/scene/gui/control.h
+++ b/scene/gui/control.h
@@ -314,7 +314,7 @@ class Control : public CanvasItem {
 
 	// Focus.
 
-	void _window_find_focus_neighbor(const Vector2 &p_dir, Node *p_at, const Point2 *p_points, real_t p_min, real_t &r_closest_dist, Control **r_closest);
+	void _window_find_focus_neighbor(const Vector2 &p_dir, Node *p_at, const Point2 *p_points, Rect2 &p_clamp, real_t p_min, real_t &r_closest_dist, Control **r_closest);
 	Control *_get_focus_neighbor(Side p_side, int p_count = 0);
 
 	// Theming.