Unity UI and New Input System
Unity UI can invoke methods in monobehaviour targets using Unity events. That's not useful if you want, say, a button click to send a message to a tile.
If you're using the New Input System it can be handly to translate a mouse click or some other Action to locate and message a tile.
TpGuidToAction
This component can be used as a target for a Unity UI control, it just sends a message to a tile that's specified by a GUID. You can see how to use this in the AnimatedTiles demo (Animation-UnityUI scene).
TpInputActionToTile
This component converts New Input System actions into TPT tile locations and can send a message to a target tile if you click on it. An example can be found in the AnimatedTilesDemo (Animation-MouseClicksDirect) and in the Layout demo. It's also used for the 'UI system'
This component is an easy to use front-end for a TpActionToTile scriptable object instance. Check out the source code for this class if you'd like to dig into what's going on. But generally the component is a better way to use this feature.
This is a Ui-Elements custom inspector that expands and contracts fields as needed depending on how you set it up.
There's a lot to unpack:
The very top section is an area where you can specify one or more pairs of Camera and Tilemap. Cameras and Tilemaps go together since both of those components are needed in order to translate from screen coordinates to tilemap coordinates. You can have multiple pairs as needed, and a priority value can be used to select a tile target when two tiles overlap the same position.
The priority value is used when you have multiple tilemaps unless Use Renderer Sort is checked.
- If checked, priority is set with the Tilemaps' Sorting Layers and Order in Layer values.
If No Messaging is checked then evaluation stops prior to sending a message for Clicks (only) and only the OnBeforeMessageSent or OnNoMessageSent callbacks are used for this Tilemap.
If Use Position Db is checked then the PositionDb Service is used to locate tiles. This is useful when you have tiles with scaled sprites or if you're tweening position and/or scale.
In the image, Enable Hover is unchecked so the HoverAction name field isn't shown. Normally you don't care about Hover.
Click On Mouse Down a click = mouse down. If not, a click = mouse up (i.e., after button released).
Handle Events: If checked, handle all events in this component. This only works for cases where ALL of the event response is dictated by Event or Zone actions that can automatically be invoked by TpEvents.ProcessEvents.
Emit Events: If checked, the message sent to the tile specifies that it can post an event if that's appropriate.
The optional Sound Controls section lets you add audio feedback.
The Ui/Messaging section lets you add direction info to packets and show a prefab at the click position.
Add Direction 4 and Add Direction 8 : this is a little harder to explain.
These are used when you want to know where in the tile the mouse pointer actually was. This may sound strange but consider that a tile with an unscaled sprite essentially occupies one Tilemap unit. But the mouse click can be anywhere within that space.
The ActionToTile packet sent by this component includes an offset which is the Vector2 distance from the center of the tile to where the click actually was.
If an add box is checked then that Vector2 position is converted into an angle and then into a value from the Position4 (up/right/down/left) or Position8 (up, upright, right ....). The Center Dead Zone describes what part of the sprite's area is considered as None from the two Position enums.
So what does all that mean? If you enable this feature then a message recipient can determine if it was clicked in the center area or on one of the edges.
You can see this at work in the Oddities/Jumper demo, where clicking on the edges of a tile moves it in the direction of where it was clicked.
When using PositionDb this feature works correctly for scaled or position-shifted sprites, even if they no longer overlap the actual tile position.
Another way of thinking about this feature:
The packets have information about where within the tile the click actually occurred as well as 4 or 8-way direction info (meaning you don't usually have to evaluate the position within the tile).
The direction info is evaluated as a rotation clockwise from straight up. E.G. one can interpret DirectionType4.Right as 'move this tile to the right' or DirectionType8.RightUp as move diagonally up and to the right.