Script:Backpack
From Roll20 Wiki
API Script
Author: Ken L.
Version: 1.25
Last Modified: 2015-6-24
Code: NA
Dependencies: None
Conflicts: Unknown
Contents |
Backpack is a journal based inventory system that updates the 'bio' section of a journal to represent a graphic inventory interface. This allows GMs whom implement this script to allow players to manage a graphic representation of their inventory. Once setup, you can move, give, drop, and pickup items through the use of the API button interface as well as buy and sell from shops and stores should they be prepared.
To use this script requires quite a bit of setup on the part of the GM preparing the asset and item databases. The asset database is simply a list of available item types/subtypes and their associated images. The item database is a list of parsable item definitions which can be short hand written to loot drops or any backpack compatible journal entry.
Getting Started
Once you load the backpack.js and backpack_tmp.js scripts into your campaign, you'll need to at least create an asset database.
After creating an asset database, you're ready to populate backpack compatible journal entries as inventories, stores, or loot cache drops.
General Use
TODO
Item Definitions
Item definitions are the format in which entries of items are parsed into the script. They consist of several parts.
[quantity] <name>;<type> [weight] [value] [description] [use] [maxcharge] [enigma]
Formally:[quantity]
name
type
[optionals]
[quantity]
name
type
subtype
[optionals]
name
→ Name of the item, see name
type
→ Existing type in backpack_tmp.js, see type
sybtype
→ Existing subtype defined in the asset database, see subtype
quantity
→ Optional quantity of the item, see quantity
weight
→ Optional weight of the item in lbs, see weight
value
→ Optional value of the item, see value
description
→ Optional description of the item, see description
use
→ Optional use argument to be executed, see use
maxcharge
→ Optional max charges of the item, see charges
enigma
→ Optional enigma arguments, see enigmas
name
The name parameter is essential to the item definition and must be unique for this item. Names of items are case insensitive and considered first class citizens along with enigma names. Names can contain any character including numbers but cannot start with a number else that number will be considered a quantity.
Names have a special suffix case where if it has a suffix of [<number>]
it can denote charges. In this case the name of the item is everything preceding this suffix. For the example of 'Wand of Bless[50]'
, 'Wand of Bless'
is the base item name, and '[50]'
is parsed out as the number of charges this item has. This is such that items of the same charge amount can stack and separate in quantity as they're used. Clearly an item named 'Staff of bots'
and 'Staff of bolts[10]'
would be seen as the same item; but one definition denotes that the item has charges, and the other does not, 'Staff of bolts'
is not the same as 'Staff of bolts[0]'
despite having the same name identifier. For the purposes of charging this item, 'Staff of bolts[0]'
could be charged and 'Staff of bolts'
could not.
If there are multiple items with the same name identifier the combined result of the receiving location will have its quantity increased even if the donating location's item definition is different in other areas from the receiving location's definition.
An example would be moving a 'flute' from A → B where say A has 5 flutes and B has 2 flutes. The difference between A and B's flutes despite having the same name is that they have different descriptions or weights despite having the same primary identifier as 'flute'. If you move 1 flute A → B then B would have 3 flutes and A 4 as expected, but B will simply have it's quantity altered, as opposed to another 'flute' item being generated matching A's flute definition.
A simple resolution to this to have the name be more descriptive such as 'Alfreds Flute' and 'Bernard's Flute'. Special care must be taken such that these names do not conflict with introduced enigma names
type
The type parameter is essential to the item definition as it connects the item definition to a display template that exists in backpack_tmp.js as well as an image for the type. A legal type is defined within the script, therefore only a fixed number of types exist. This can be extended upon by editing backpack_tmp.js, see customizing for details. All types are case sensitive and can only include characters [A-Za-z] plus '-' and '_'.
Type name | Description |
---|---|
potion | template for potions |
weapon | template for weapons |
armor | template for armor |
wand | template for potions |
staff | template for staves |
ring | template for rings |
scroll | template for scrolls |
misc | template for miscellaneous |
food | template for food |
treasure | template for treasure |
gem | template for gems |
No item definition can exist without a valid type, compared to subtypes which are optional, and enumerable within the asset database .
subtype
The subtype is not essential to to the item definition so long as the type it branches off exists. Subtypes exist primarily for the purpose of image enumeration categorized by type. For example from scroll:scroll_ancient
we can extract scroll
as the type and scroll_ancient
as the subtype. scroll:scroll_ancient
could refer to a withered image of parchment where as scroll:scroll_empowered
could refer to an image of a glowing scroll. There are no naming conventions other than what is a legal type name so weapon:greataxe
is valid as well.
Types (type and subtype) as presented by this script are used to
A.) Provide a template for the item
B.) Allow propagation for item images related to the base type
quantity
The quantity of an item is optional to the item definition but is never left undefined. If not provided it represents an infinite pool of the item for backpack journals configured as stores, but otherwise defaults to 1 for all other purposes.
weight
The weight of an item is optional and considered 0, or weightless if not provided.
value
description
use
charges
enigmas
Asset Database
The asset database is a journal entry that contains within its gmnotes section the library of images to be used for item definitions through their type and subtype
The asset database has a simple format where each line is a single asset entry (blank lines between groups of entries are fine).
Each asset entry is in either of the following formats:
<type>:<link>
<type>:<subtype>:<link>
Formally:
type
subtype
link
type
link
type
→ Existing type in backpack_tmp.js
sybtype
→ Anything except ε
link
→ HTML link to the image source, must start with 'http' case insensitive
Item Database
TODO
Customizing
TODO
Changelog
TODO