Improve documentation for tooltip-related methods

doc/classes/Control.xml

@@ -113,7 +113,7 @@
 			<param index="0" name="at_position" type="Vector2" />
 			<description>
 				Virtual method to be implemented by the user. Returns the tooltip text for the position [param at_position] in control's local coordinates, which will typically appear when the cursor is resting over this control. See [method get_tooltip].
-				[b]Note:[/b] If this method returns an empty [String], no tooltip is displayed.
+				[b]Note:[/b] If this method returns an empty [String] and [method _make_custom_tooltip] is not overridden, no tooltip is displayed.
 			</description>
 		</method>
 		<method name="_gui_input" qualifiers="virtual">
@@ -164,11 +164,12 @@
 			<return type="Object" />
 			<param index="0" name="for_text" type="String" />
 			<description>
-				Virtual method to be implemented by the user. Returns a [Control] node that should be used as a tooltip instead of the default one. The [param for_text] includes the contents of the [member tooltip_text] property.
+				Virtual method to be implemented by the user. Returns a [Control] node that should be used as a tooltip instead of the default one. [param for_text] is the return value of [method get_tooltip].
 				The returned node must be of type [Control] or Control-derived. It can have child nodes of any type. It is freed when the tooltip disappears, so make sure you always provide a new instance (if you want to use a pre-existing node from your scene tree, you can duplicate it and pass the duplicated instance). When [code]null[/code] or a non-Control node is returned, the default tooltip will be used instead.
 				The returned node will be added as child to a [PopupPanel], so you should only provide the contents of that panel. That [PopupPanel] can be themed using [method Theme.set_stylebox] for the type [code]"TooltipPanel"[/code] (see [member tooltip_text] for an example).
 				[b]Note:[/b] The tooltip is shrunk to minimal size. If you want to ensure it's fully visible, you might want to set its [member custom_minimum_size] to some non-zero value.
 				[b]Note:[/b] The node (and any relevant children) should have their [member CanvasItem.visible] set to [code]true[/code] when returned, otherwise, the viewport that instantiates it will not be able to calculate its minimum size reliably.
+				[b]Note:[/b] If overridden, this method is called even if [method get_tooltip] returns an empty string. When this happens with the default tooltip, it is not displayed. To copy this behavior, return [code]null[/code] in this method when [param for_text] is empty.
 				[b]Example:[/b] Use a constructed node as a tooltip:
 				[codeblocks]
 				[gdscript]
@@ -553,7 +554,7 @@
 			<description>
 				Returns the tooltip text for the position [param at_position] in control's local coordinates, which will typically appear when the cursor is resting over this control. By default, it returns [member tooltip_text].
 				This method can be overridden to customize its behavior. See [method _get_tooltip].
-				[b]Note:[/b] If this method returns an empty [String], no tooltip is displayed.
+				[b]Note:[/b] If this method returns an empty [String] and [method _make_custom_tooltip] is not overridden, no tooltip is displayed.
 			</description>
 		</method>
 		<method name="grab_click_focus">
@@ -1065,7 +1066,8 @@
 			[b]Note:[/b] Tooltips customized using [method _make_custom_tooltip] do not use this auto translate mode automatically.
 		</member>
 		<member name="tooltip_text" type="String" setter="set_tooltip_text" getter="get_tooltip_text" default="&quot;&quot;">
-			The default tooltip text. The tooltip appears when the user's mouse cursor stays idle over this control for a few moments, provided that the [member mouse_filter] property is not [constant MOUSE_FILTER_IGNORE]. The time required for the tooltip to appear can be changed with the [member ProjectSettings.gui/timers/tooltip_delay_sec] option. See also [method get_tooltip].
+			The default tooltip text. The tooltip appears when the user's mouse cursor stays idle over this control for a few moments, provided that the [member mouse_filter] property is not [constant MOUSE_FILTER_IGNORE]. The time required for the tooltip to appear can be changed with the [member ProjectSettings.gui/timers/tooltip_delay_sec] setting.
+			This string is the default return value of [method get_tooltip]. Override [method _get_tooltip] to generate tooltip text dynamically. Override [method _make_custom_tooltip] to customize the tooltip interface and behavior.
 			The tooltip popup will use either a default implementation, or a custom one that you can provide by overriding [method _make_custom_tooltip]. The default tooltip includes a [PopupPanel] and [Label] whose theme properties can be customized using [Theme] methods with the [code]"TooltipPanel"[/code] and [code]"TooltipLabel"[/code] respectively. For example:
 			[codeblocks]
 			[gdscript]