Conveyor Items
Items have two sides to them:
Conveyor ItemandConveyor Item Descriptor.
Descriptors will describe an item type, while items will be the individual items running on conveyors.
In This Page:
Conveyor Item Descriptor
Any UObject can be a descriptor, but it is suggested that data assets (UDataAsset or UPrimaryDataAsset) are used.
In order for an object to be considered a descriptor, it must implement Conveyor Item Interface and it must override the GetItemDescriptor() function.
Included in the plugin is a data asset type, Conveyor Item Data, which implements the logic in the simplest way possible.
The data required is a Conveyor Item Descriptor struct, which is composed as follows:
| Property | Type | Description |
|---|---|---|
| Mesh | Static Mesh | The visual mesh for the item. |
| Local Mesh Transform | Transform | The local transform of the mesh. |
| Material Overrides | Material Interface Array | (Optional) Material overrides for the mesh. |
You can manually register item types with the system using the Register Conveyor Item Type function from the Conveyor Statics library. This will allow the system to keep the object reference alive for the duration of the level-s lifetime. While this is not required, it is recommended to do so to avoid garbage collection issues, especially if the item types is dynamically generated (not a data asset).
The function returns true if the item type was successfully registered, false otherwise (if the passed object does not implement the required interface or if the object is invalid).
Conveyor Item
Conveyor items are simple structures. They store a Conveyor Item Interface object reference (in the form of a TScriptInterface) and a Payload which you can use to stora any custom data you need in the form of a FInstancedStruct.
Creating and invalidating items is as simple as setting the Item Data property to whatever you want, null if you want to invalidate the item (Or use the Invalidate Conveyor Item function from the Conveyor Statics library).
Item payloads will not be seen by Unreal’s Garbage Collection, so you shouldn’t store UObject references in them unless you are keeping them alive elsewhere.