Attach points allow you to dynamically attach object models to characters, tiles, or even other objects during the game (for example, to place a sword into a character's hand, a torch onto a dungeon wall, or a book onto a table).
Attach points for models can be created with the “Create Attach Point” tool in the Voxel Editor. This tool can be selected using the shortcut key of “F8” or by clicking on the tool button with the “link” icon on the Model Tools panel. While active, left-clicking a voxel will place an attach point at that coordinate. The attach point's location can be adjusted later using the offset sliders (see next section).
After left-clicking a voxel, the editor will prompt for an attach point ID. Each attach point within a model frame must have an ID that is unique to that frame. Once added, a white cube with a “link” icon will be displayed at the new attach point's location.
To change the ID for an attach point, selected the desired ID from the “Attach Points” dropdown on the Model Properties Panel, then click the “pencil” button to the right of the dropdown. A popup dialog will be displayed prompting for the new ID.
To remove a previously created attach point, select the desired ID from the “Attach Points” dropdown on the Model Properties panel, then click the red “X” button to the right of the dropdown. A popup dialog will be displayed to confirm its removal.
There are several properties that can be adjusted for attach points from the Model Properties panel: offset, rotation, and scale. These properties affect an object's appearance when attached to that particular attach point. The settings for these properties can be assigned per frame, allowing attached objects to be animated along with the parent model.
| Property | Description |
|---|---|
| Offset | The offset values define the position of the attach point within the frame and is relative to the model grid's center (at ground level). When an object model (the “child”) is attached to an entity (the “parent”), the attach points for the parent and child models will be connected together at their respective attach point locations. |
| Rotation | The rotation values determine the angle of an attached object. This can be used, for example, to angle a sword downward along with the swinging of a character's arm during an attack animation. |
| Scale Factor | The scale factor value determines the size of an object when attached to an attach point. A scale factor of 1 will keep the model's original size, whereas a value of 2 will double the model's size. The default scale factor of 1.05 will enlarge models slightly to help prevent z-fighting. |
Once you've set up any necessary attach points for your objects and the models to which they will be attached, you can use the Attach Object scripting function to trigger an object to be attached to a target entity in-game, for example to attach a torch to a wall tile when the player interacts with it.
The example below will attach the “sword” object model's “handle” attach point to the player's “right_hand” attach point.
attach_object("sword", player, "handle", "right_hand");
Alternately, you can create attach points for the sword object and player character using the same ID (e.g. “hand”) and leave out the function's fourth parameter.
attach_object("sword", player, "hand");
To detach a previously attached object, you can use the Detach Object scripting function, for example to remove a book from a table when the player interacts with the table.
The example below will detach the object currently attached to the player's “right_hand” attach point.
detach_object(player, "right_hand");
You can reference the object that's currently attached to an attach point using the “attachment” property with the desired attach point ID. In the example below, the “glow” animation will be played for the object attached to the player's “right_hand” attach point.
play_animation(player.attachment["right_hand"], "glow");
Although most of the equipment system is yet to be implemented, there is some experimental functionality that can be used to automatically attach models to a character whenever an item is equipped. The steps below can be followed to create an equippable item with a corresponding object model.
1) Toggle the “Equippable” setting to “On” for the item in the Item Editor.
2) Assign an object model to the item in the Item Editor.
3) Create an attach point for both the character and object that matches the equipment slot ID (e.g. “right_hand”).
4) Call the Equip Item scripting function to equip the item to the appropriate slot (e.g. “right_hand”) and the object will automatically be attached to the corresponding attach point.
equip_item(player, "right_hand", "ITEM_0001");
With this setup, calling the Unequip Item scripting function will automatically detach the object model associated with the item that is unequipped.
unequip_item(player, "right_hand");