Inventory quality-of-life improvements

[balloonpopper]

Is your feature request related to a problem? Please describe. I've been playing around with the inventory items, and I would like to request a refactor. I've found that the inventory is currently not intuitive and is hard / confusing to use. Things don't work how I'd expect them to, and the error messages aren't helpful.

Describe the solution you'd like Here's my thoughts after trying to update room 5 of the demo:

• There should be a global set of commands that work with all inventory items (eg. use / give). I shouldn't have to fill in "Combine when selected action is in" for each inventory item.
• All inventory items should be able to perform these actions against every ESCitem. (e.g. I should be able to try to use the wrench or the pen on the player or the button without having to code specific interations)
• There should be a set of default responses that are chosen (either at random or sequentially - developers choice) when a specific interaction hasn't been programmed. e.g. "use pen on button" would respond with "That doesn't work" or "No, I don't think so" if I haven't programmed that interaction.
• "Combine is one way" needs to be clarified as it's not mentioned in the documentation that I can find. I am not sure with "one-way combines" which of the two objects needs to have this selected (if I'm combining pen with paper, and I can't combine paper with pen, is the pen or the paper or both the one that I select "one way combine" on?)
• Documentation is updated to include how to combine items (including step-by-step guide)
• Documentation covers combining a combined item with another item. 'Pen' with 'paper', then the (new) 'filled-in piece of paper' with 'folder'.
• Items have a quantity.
• Items can be shown as a group or individually in the inventory (developers choice?) e.g if I pick up 2 coins, do I see 2 inventory slots containing a coin each, or do I see a single inventory slot containing 2 coins (in which case the inventory needs a quantity indicator for each slot)
• If the inventory supports quantities, commands would be needed to check the quantity, and add/subtract an amount. This would allow me to have 30 gold pieces, and pay 5 of them for an item for example.
• If the inventory supports quantities, the quantity is possibly shown in a tooltip
• If the combine is not one-way, either object should be able to have the combine commands (e.g. if I combine 'pen' with 'paper' I should be able to have either ":use pen" in "paper"'s script, or ":use paper" in "pen"'s script but both shouldn't be required)

If the above doesn't go ahead (or possibly in addition to the above but as short term goals)

• The error messages at the moment aren't intuitive. The error messages should tell me
  • When I can't use an inventory item as it doesn't have "use" set up in "Combine when selected action is in"
  • When I can't use the inventory item as the destination object doesn't have the correct "use" code for this object
  • When the combined item is missing from the autoregister folder
• The documentation needs to mention what you need to do to allow items to be merged (you need a scene in the autoregister folder, "Combine when selected action is in" needs "use", and it needs to say which item needs the one-way button selected)
• The documentation should mention that inventory_add will instantiate the scene from the autoregister folder automatically into your inventory

[dploeger]

There's a lot in here that should go into separate features, I'd say. @StraToN @BHSDuncan We should discuss the different points. But I'd say, this should be targeted at future, because the inventory basically works.