Want to use interface for lootable items but don't know where to start

[Kurt-Dekker]

Sounds like there’s not one interface.

A creature or chest might be ILootable

As a result it might return an ILoot object

An ILoot object might contain items, which might express the IItem interface.

Or an ILoot object might just contain currency, perhaps expressing an ICurrency interface.

Just know that ALL of this sort of “abstractery” behavior is DEEP into advanced coding territory, especially inventories.

Below is my Inventory blurb and my Interfaces blurb:

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These things (inventory, shop systems, character customization, dialog tree systems, crafting, etc) are fairly tricky hairy beasts, definitely deep in advanced coding territory.

Inventory code never lives “all by itself.” All inventory code is EXTREMELY tightly bound to prefabs and/or assets used to display and present and control the inventory. Problems and solutions must consider both code and assets as well as scene / prefab setup and connectivity.

Inventories / shop systems / character selectors all contain elements of:

• a database of items that you may possibly possess / equip
• a database of the items that you actually possess / equip currently
• perhaps another database of your “storage” area at home base?
• persistence of this information to storage between game runs
• presentation of the inventory to the user (may have to scale and grow, overlay parts, clothing, etc)
• interaction with items in the inventory or on the character or in the home base storage area
• interaction with the world to get items in and out
• dependence on asset definition (images, etc.) for presentation

Just the design choices of such a system can have a lot of complicating confounding issues, such as:

• can you have multiple items? Is there a limit?
• if there is an item limit, what is it? Total count? Weight? Size? Something else?
• are those items shown individually or do they stack?
• are coins / gems stacked but other stuff isn’t stacked?
• do items have detailed data shown (durability, rarity, damage, etc.)?
• can users combine items to make new items? How? Limits? Results? Messages of success/failure?
• can users substantially modify items with other things like spells, gems, sockets, etc.?
• does a worn-out item (shovel) become something else (like a stick) when the item wears out fully?
• etc.

Your best bet is probably to write down exactly what you want feature-wise. It may be useful to get very familiar with an existing game so you have an actual example of each feature in action.

Once you have decided a baseline design, fully work through two or three different inventory tutorials on Youtube, perhaps even for the game example you have chosen above.

Breaking down a large problem such as inventory:

Weapon Inventory and how to script weapons.

You’re welcome of course. One thing you could try to really get a “feel” for what happens in this case is make a simple script that is just one cell of your inventory. Put this into a script that you can access through an “inventory API” that does certain things to a cell. These functions might be: “Set the type of item” “Query the type and quantity of item in this cell” “Add 1 item to this cell.” “Add N number of items to this cell.” “Remove N item from this cell.” Then you can have pr…

If you want to see most of the steps involved, make a “micro inventory” in your game, something whereby the player can have (or not have) a single item, and display that item in the UI, and let the user select that item and do things with it (take, drop, use, wear, eat, sell, buy, etc.).

Everything you learn doing that “micro inventory” of one item will apply when you have any larger more complex inventory, and it will give you a feel for what you are dealing with.

Breaking down large problems in general:

Options for implementing mining/digging in an asteroid belt game?

Whenever engineering seems too much to tackle, it's always best to see if you can break the problem down. What you describe above is by no means simple, as just the different ways all of it could be implemented are complex: does the camera rotate with the player on the asteroid? Do the player's controls rotate as they walk around the asteroid? Does the camera lock to the rotating asteroid? What does the camera do if the player digs down a ways? If the player digs a tunnel into the asteroid,…

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Using Interfaces in Unity3D:

How can I detect/catch the SendMessageOptions.RequireReceiver error message?

SendMessage is kind of antiquated. The way to do things today is to make an interface. That way you say “is there this interface?” and check if it’s not null, then call the method you want if it is. Don’t be afraid, it’s pretty simple, and it’s way more powerful. Here, soooper-quickly: // stick this in its own file, usually IMyInterface.cs public interface IMyInterface { void MyMethod( int arg1, string arg2); } Now, in whatever Monobehaviors you have, you implement that interface, which ba…

Manager classes

Looks reasonable... you might get some benefit by extracting common methods into some kind of interface, which is a pattern that works really well with Unity and MonoBehaviors. MBs can then implement specific interfaces and be found because they implement those interfaces. For instance, you might have an IAttackable interface that can represent a target that can be attacked. Some of its methods might be "what can hurt you?" and "you have been attacked by ..." This also means when a projectile …

Check Youtube for other tutorials about interfaces and working in Unity3D. It’s a pretty powerful combination.