Add option to swap Alt+scroll zooming behavior in 2D editor

Update doc/classes/EditorSettings.xml

Co-authored-by: Hugo Locurcio <hugo.locurcio@hugo.pro>

doc/classes/EditorSettings.xml

@@ -237,6 +237,9 @@
 		<member name="editors/2d/smart_snapping_line_color" type="Color" setter="" getter="">
 			The color to use when drawing smart snapping lines in the 2D editor. The smart snapping lines will automatically display when moving 2D nodes if smart snapping is enabled in the Snapping Options menu at the top of the 2D editor viewport.
 		</member>
+		<member name="editors/2d/use_integer_zoom_by_default" type="bool" setter="" getter="">
+			If [code]true[/code], the 2D editor will snap to integer zoom values while not holding the [kbd]Alt[/kbd] key and powers of two while holding it. If [code]false[/code], this behavior is swapped.
+		</member>
 		<member name="editors/2d/viewport_border_color" type="Color" setter="" getter="">
 			The color of the viewport border in the 2D editor. This border represents the viewport's size at the base resolution defined in the Project Settings. Objects placed outside this border will not be visible unless a [Camera2D] node is used, or unless the window is resized and the stretch mode is set to [code]disabled[/code].
 		</member>

editor/editor_settings.cpp

@@ -686,6 +686,7 @@ void EditorSettings::_load_defaults(Ref<ConfigFile> p_extra_config) {
 	_initial_set("editors/2d/bone_outline_color", Color(0.35, 0.35, 0.35, 0.5));
 	_initial_set("editors/2d/bone_outline_size", 2);
 	_initial_set("editors/2d/viewport_border_color", Color(0.4, 0.4, 1.0, 0.4));
+	_initial_set("editors/2d/use_integer_zoom_by_default", false);
 
 	// Panning
 	// Enum should be in sync with ControlScheme in ViewPanner.

editor/plugins/canvas_item_editor_plugin.cpp

@@ -1289,7 +1289,13 @@ void CanvasItemEditor::_zoom_callback(float p_zoom_factor, Vector2 p_origin, Ref
 	if (mb.is_valid()) {
 		// Special behvior for scroll events, as the zoom_by_increment method can smartly end up on powers of two.
 		int increment = p_zoom_factor > 1.0 ? 1 : -1;
-		zoom_widget->set_zoom_by_increments(increment, mb->is_alt_pressed());
+		bool by_integer = mb->is_alt_pressed();
+
+		if (EDITOR_GET("editors/2d/use_integer_zoom_by_default")) {
+			by_integer = !by_integer;
+		}
+
+		zoom_widget->set_zoom_by_increments(increment, by_integer);
 	} else {
 		zoom_widget->set_zoom(zoom_widget->get_zoom() * p_zoom_factor);
 	}