DOCS: Update UI Support with project wide actions (#1815)

* CHANGE: Update public docs with updated information on how to customise UITK integration using project wide actions.

---------

Co-authored-by: Ben Pitt <benp@unity3d.com>
Co-authored-by: Håkan Sidenvall <hakan.sidenvall@unity3d.com>

Author: 3 people

Packages/com.unity.inputsystem/Documentation~/Images/ProjectSettingsInputActionsUIActionMap.png

@@ -13,14 +13,30 @@ uid: input-system-ui-support
 * [UI and game input](#ui-and-game-input)
 * [UI Toolkit support](#ui-toolkit-support)
 
-You can use the Input System package to control any in-game UI created with the [Unity UI package](https://docs.unity3d.com/Manual/UISystem.html). The integration between the Input System and the UI system is handled by the [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) component.
+You can use the Input System package to control any in-game UI bindings created with the [Unity UI package](https://docs.unity3d.com/Manual/UISystem.html).
 
->[!NOTE]
->The Input System package does not support IMGUI. If you have `OnGUI` methods in your player code (Editor code is unaffected), Unity does not receive any input events in those methods when the **Active Input Handling** [Player Setting](https://docs.unity3d.com/Manual/class-PlayerSettings.html) is set to **Input System Package**. To restore functionality you can change the setting to **Both**, but this means that Unity processes the input twice.
+
+From **Unity 2023.2** onwards, the Input System and UI Toolkit are fully integrated with each other. To configure UI Input you can configure the UI action map of [project-wide actions](Workflow-Actions.html) in **Project Settings > Input System Package > Input Actions**.
+
+For older versions of Unity, the integration between the Input System and the UI system is handled by the [Input System UI Input Module](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) component.
+
+
+> **Note:** The Input System package does not support [Immediate Mode GUI](https://docs.unity3d.com/Manual/GUIScriptingGuide.html) (IMGUI). If you have `OnGUI` methods in your player code (Editor code is unaffected), Unity does not receive any input events in those methods when the **Active Input Handling** [Player Setting](https://docs.unity3d.com/Manual/class-PlayerSettings.html) is set to **Input System Package**. To restore functionality you can change the setting to **Both**, but this means that Unity processes the input twice.
 
 ## Setting up UI input
 
-The [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) component acts as a drop-in replacement for the [StandaloneInputModule](https://docs.unity3d.com/Manual/script-StandaloneInputModule.html) component that the Unity UI package. [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) provides the same functionality as  [StandaloneInputModule](https://docs.unity3d.com/Manual/script-StandaloneInputModule.html), but it uses the Input System instead of the legacy Input Manager to drive UI input.
+When using [project-wide actions](Workflow-Actions.html) in Unity 2023.2 and newer, you can configure the UI action map in **Project Settings > Input System Package > Input Actions**.
+
+![ProjectSettingsInputActionsUIActionMap](Images/ProjectSettingsInputActionsUIActionMap.png)
+
+You can modify, add, or remove bindings to the named actions in the UI action map to suit your project, however in order to remain compatible with UI Toolkit, the name of the action map ("UI") and the names of the actions it contains ("Navigate", "Submit", "Cancel", etc) and their respective *Action Types* must remain the same to be compatible with expectations indirectly defined by the [UI Input Module](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) class.
+
+You can also reset the UI action map to its default bindings by selecting **Reset** from the **More (⋮)** menu, at the top right of the actions editor window. However, this will reset both the 'Player' and 'UI' action maps to their default bindings.
+
+> **Note:**
+> If you have an instance of the [Input System UI Input Module](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) component in your scene, the settings on that component takes priority and are used instead of the UI settings in your project-wide actions.
+
+For versions of Unity prior to Unity 2023.2, the [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) component acts as a drop-in replacement for the [StandaloneInputModule](https://docs.unity3d.com/Manual/script-StandaloneInputModule.html) component that the Unity UI package has. [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) provides the same functionality as  [StandaloneInputModule](https://docs.unity3d.com/Manual/script-StandaloneInputModule.html), but it uses the Input System package instead of the legacy Input Manager to drive UI input.
 
 If you have a [StandaloneInputModule](https://docs.unity3d.com/Manual/script-StandaloneInputModule.html) component on a GameObject, and the Input System is installed, Unity shows a button in the Inspector offering to automatically replace it with a [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) for you. The [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) is pre-configured to use default Input Actions to drive the UI, but you can override that configuration to suit your needs.
 
@@ -66,12 +82,12 @@ For each of these types of input, input is sourced and combined from a specific
 
 To the UI, a pointer is a position from which clicks and scrolls can be triggered to interact with UI elements at the pointer's position. Pointer-type input is sourced from [point](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_point), [leftClick](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_leftClick), [rightClick](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_rightClick), [middleClick](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_middleClick), and [scrollWheel](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_scrollWheel).
 
->[!NOTE]
+>**Note:**
 >The UI input module does not have an association between pointers and cursors. In general, the UI is oblivious to whether a cursor exists for a particular pointer. However, for mouse and pen input, the UI input module will respect [Cusor.lockState](https://docs.unity3d.com/ScriptReference/Cursor-lockState.html) and pin the pointer position at `(-1,-1)` whenever the cursor is locked. This behavior can be changed through the [Cursor Lock Behavior](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_cursorLockBehavior) property of the [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html).
 
 Multiple pointer Devices may feed input into a single UI input module. Also, in the case of [Touchscreen](../api/UnityEngine.InputSystem.Touchscreen.html), a single Device can have the ability to have multiple concurrent pointers (each finger contact is one pointer).
 
->[!IMPORTANT]
+>**Important:**
 >Because multiple pointer Devices can feed into the same set of Actions, it is important to set the [action type](./RespondingToActions.md#action-types) to [PassThrough](../api/UnityEngine.InputSystem.InputActionType.html#UnityEngine_InputSystem_InputActionType_PassThrough). This ensures that no filtering is applied to input on these actions and that instead every input is relayed as is.
 
 From the perspective of [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html), each [InputDevice](../api/UnityEngine.InputSystem.InputDevice.html) that has one or more controls bound to one of the pointer-type actions is considered a unique pointer. Also, for each [Touchscreen](../api/UnityEngine.InputSystem.Touchscreen.html) devices, each separate [TouchControl](../api/UnityEngine.InputSystem.Controls.TouchControl.html) that has one or more of its controls bound to the those actions is considered its own unique pointer as well. Each pointer receives a unique [pointerId](https://docs.unity3d.com/Packages/com.unity.ugui@1.0/api/UnityEngine.EventSystems.PointerEventData.html#UnityEngine_EventSystems_PointerEventData_pointerId) which generally corresponds to the [deviceId](../api/UnityEngine.InputSystem.InputDevice.html#UnityEngine_InputSystem_InputDevice_deviceId) of the pointer. However, for touch, this will be a combination of [deviceId](../api/UnityEngine.InputSystem.InputDevice.html#UnityEngine_InputSystem_InputDevice_deviceId) and [touchId](../api/UnityEngine.InputSystem.Controls.TouchControl.html#UnityEngine_InputSystem_Controls_TouchControl_touchId). Use [ExtendedPointerEventData.touchId](../api/UnityEngine.InputSystem.UI.ExtendedPointerEventData.html#UnityEngine_InputSystem_UI_ExtendedPointerEventData_touchId) to find the ID for a touch event.
@@ -84,7 +100,7 @@ You can influence how the input module deals with concurrent input from multiple
 |[Single Unified Pointer](../api/UnityEngine.InputSystem.UI.UIPointerBehavior.html#UnityEngine_InputSystem_UI_UIPointerBehavior_SingleUnifiedPointer)|All pointer input is unified such that there is only ever a single pointer. This includes touch and tracked input. This means, for example, that regardless how many devices feed input into [Point](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_point), only the last such input in a frame will take effect and become the current UI pointer's position.|
 |[All Pointers As Is](../api/UnityEngine.InputSystem.UI.UIPointerBehavior.html#UnityEngine_InputSystem_UI_UIPointerBehavior_AllPointersAsIs)|The UI input module will not unify any pointer input. Any device, including touch and tracked devices that feed input pointer-type actions, will be its own pointer (or multiple pointers for touch input).<br><br>Note: This might mean that there will be an arbitrary number of pointers in the UI, and several objects might be pointed at concurrently.|
 
->[!NOTE]
+>**Note:**
 >If you bind a device to a pointer-type action such as [Left Click](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_leftClick) without also binding it to [Point](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_point), the UI input module will recognize the device as not being able to point and try to route its input into that of another pointer. For example, if you bind [Left Click](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_leftClick) to the `Space` key and [Point](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_point) to the position of the mouse, then pressing the space bar will result in a left click at the current position of the mouse.
 
 For pointer-type input (as well as for [tracked-type input](#tracked-type input)), [InputSystemUIInputModule](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html) will send [ExtendedPointerEventData](../api/UnityEngine.InputSystem.UI.ExtendedPointerEventData.html) instances which are an extended version of the base `PointerEventData`. These events contain additional data such as the [device](../api/UnityEngine.InputSystem.UI.ExtendedPointerEventData.html#UnityEngine_InputSystem_UI_ExtendedPointerEventData_device) and [pointer type](../api/UnityEngine.InputSystem.UI.ExtendedPointerEventData.html#UnityEngine_InputSystem_UI_ExtendedPointerEventData_pointerType) which the event has been generated from.
@@ -97,7 +113,7 @@ Navigation-type input controls the current selection based on motion read from t
 
 Unlike with [pointer-type](#pointer-type input), where multiple pointer inputs may exist concurrently (think two touches or left- and right-hand tracked input), navigation-type input does not have multiple concurrent instances. In other words, only a single [move](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_move) vector and a single [submit](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_submit) and [cancel](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_cancel) input will be processed by the UI module each frame. However, these inputs need not necessarily come from one single Device always. Arbitrary many inputs can be bound to the respective actions.
 
->[!IMPORTANT]
+>**Important:**
 >While, [move](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_move) should be set to [PassThrough](../api/UnityEngine.InputSystem.InputActionType.html#UnityEngine_InputSystem_InputActionType_PassThrough) Action type, it is important that [submit](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_submit) and
 [cancel](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_cancel) be set to the [Button](../api/UnityEngine.InputSystem.InputActionType.html#UnityEngine_InputSystem_InputActionType_Button) Action type.
 
@@ -107,7 +123,7 @@ Navigation input is non-positional, that is, unlike with pointer-type input, the
 
 Input from [tracked devices](../api/UnityEngine.InputSystem.TrackedDevice.html) such as [XR controllers](../api/UnityEngine.InputSystem.XR.XRController.html) and [HMDs](../api/UnityEngine.InputSystem.XR.XRHMD.html) essentially behaves like [pointer-type input](#pointer-type-input). The main difference is that the world-space device position and orientation sourced from  [trackedDevicePosition](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_trackedDevicePosition) and  [trackedDeviceOrientation](../api/UnityEngine.InputSystem.UI.InputSystemUIInputModule.html#UnityEngine_InputSystem_UI_InputSystemUIInputModule_trackedDeviceOrientation) is translated into a screen-space position via raycasting.
 
->[!IMPORTANT]
+> **Important:**
 >Because multiple tracked Devices can feed into the same set of Actions, it is important to set the [action type](./RespondingToActions.md#action-types) to [PassThrough](../api/UnityEngine.InputSystem.InputActionType.html#UnityEngine_InputSystem_InputActionType_PassThrough). This ensures that no filtering is applied to input on these actions and that instead every input is relayed as is.
 
 For this raycasting to work, you need to add [TrackedDeviceRaycaster](../api/UnityEngine.InputSystem.UI.TrackedDeviceRaycaster.html) to the `GameObject` that has the UI's `Canvas` component. This `GameObject` will usually have a `GraphicRaycaster` component which, however, only works for 2D screen-space raycasting. You can put [TrackedDeviceRaycaster](../api/UnityEngine.InputSystem.UI.TrackedDeviceRaycaster.html) alongside `GraphicRaycaster` and both can be enabled at the same time without advserse effect.
@@ -130,12 +146,12 @@ The properties of the [MultiplayerEventSystem](../api/UnityEngine.InputSystem.UI
 
 ## Virtual mouse cursor control
 
->[!NOTE]
+> **Note:**
 >While pointer input generated from a `VirtualMouseInput` component is received in UI Toolkit, the `VirtualMouseInput` component is not officially supported for use with [UI Toolkit](#ui-toolkit-support). At the moment, it only works in combination with the [Unity UI](https://docs.unity3d.com/Manual/com.unity.ugui.html) system.
 
 If your application uses gamepads and joysticks as an input, you can use the [navigation Actions](#navigation-type-input) to operate the UI. However, it usually involves extra work to make the UI work well with navigation. An alternative way to operate the UI is to allow gamepads and joysticks to drive the cursor from a "virtual mouse cursor".
 
->[!TIP]
+> **Tip:**
 >To see an example of a [VirtualMouseInput](../api/UnityEngine.InputSystem.UI.VirtualMouseInput.html) setup, see the [Gamepad Mouse Cursor sample](Installation.md#installing-samples) included with the Input System package.
 
 To set this up, follow these steps:
@@ -145,7 +161,7 @@ To set this up, follow these steps:
 3. If you want the virtual mouse to control the system mouse cursor, set [Cursor Mode](../api/UnityEngine.InputSystem.UI.VirtualMouseInput.html#UnityEngine_InputSystem_UI_VirtualMouseInput_cursorMode) to `Hardware Cursor If Available`. In this mode, the `Cursor Graphic` is hidden when a system `Mouse` is present and you use [Mouse.WarpCursorPosition](../api/UnityEngine.InputSystem.Mouse.html#UnityEngine_InputSystem_Mouse_WarpCursorPosition_UnityEngine_Vector2_) to move the system mouse cursor instead of the software cursor. The transform linked through `Cursor Transform` is not updated in that case.
 4. To configure the input to drive the virtual mouse, either add  bindings on the various actions (such as `Stick Action`), or enable `Use Reference` and link existing actions from an `.inputactions` asset.
 
->[!IMPORTANT]
+> **Important:**
 >Make sure that the `InputSystemUIInputModule` on the UI's `EventSystem` does not receive navigation input from the same devices that feed into `VirtualMouseInput`. If, for example, `VirtualMouseInput` is set up to receive input from gamepads, and `Move`, `Submit`, and `Cancel` on `InputSystemUIInputModule` are also linked to the gamepad, then the UI receives input from the gamepad on two channels.
 
 ![VirtualMouseInput](Images/VirtualMouseInput.png)
@@ -195,11 +211,18 @@ An explicit mode switch is implemented by temporarily switching to UI control wh
 
 As of Unity 2021.2, [UI Toolkit](https://docs.unity3d.com/Manual/UIElements.html) is supported as an alternative to the [Unity UI](https://docs.unity3d.com/Manual/com.unity.ugui.html) system for implementing UIs in players.
 
+### Unity 2023.2 and onwards
+
+As mentioned in the [beginning of this document](#ui-support), from Unity 2023.2 and onwards, the Input System and UI Toolkit are fully integrated with each other.
+
+
+### Unity 2023.1 and earlier
+
 Input support for both [Unity UI](https://docs.unity3d.com/Manual/com.unity.ugui.html) and [UI Toolkit](https://docs.unity3d.com/Manual/UIElements.html) is based on the same [EventSystem](https://docs.unity3d.com/Packages/com.unity.ugui@1.0/manual/EventSystem.html) and [BaseInputModule](https://docs.unity3d.com/Packages/com.unity.ugui@1.0/manual/InputModules.html) subsystem. In other words, the same input setup based on [InputSystemUIInputModule](#setting-up-ui-input) supports input in either UI solution and nothing extra needs to be done.
 
 Internally, UI Toolkit installs an event listener in the form of the `PanelEventHandler` component which intercepts events that `InputSystemUIInputModule` sends and translates them into UI Toolkit-specific events that are then routed into the visual tree. If you employ `EventSystem.SetUITookitEventSystemOverride`, this default mechanism is bypassed.
 
->[!NOTE]
+>**Note:**
 >XR ([tracked-type input](#tracked-type-input)) is not yet supported in combination with UI Toolkit. This means that you cannot use devices such as VR controllers to operate interfaces created with UI Toolkit.
 
 There are some additional things worth noting: