Lootr

Lootr \lutʁ\ is a simple RPG-like looting system.

Lootr provides a way to organize data commonly named loot in a gameplay context. It helps you to manage which items can be found, in a generic and statisticaly controlled system.

It is heavily inspired from the work of Bob Nystrom http://journal.stuffwithstuff.com/2014/07/05/dropping-loot

A JS version is available here https://github.com/vincent/lootr A C# version is available here https://github.com/Sparox/LootrCsharp

In Lootr, lootables are organized in a tree of categories and items.

Then, a collection of Drops describe how items are yield from a loot action.

equipment: 50% chances, stack of 2

This might yield 2 items in the equipment tree, for example 1 Gloves + 1 Boots

Create a loot bag

Create items.

use lootr::{Lootr, item::Item};
let mut loot = Lootr::default();

loot.add(
    Item::a("Berries")
);

Items can have properties.

use lootr::{Lootr, item::{Item, Props}};
let mut loot = Lootr::default();

loot.add(
    Item::from("crown", Props::from([
        ("strength", "10"),
        ("charisma", "+100")
    ]))
);

Each level is composed by a list of .items and nested .branchs.

Organize the loot repository by adding branchs

use lootr::Lootr;
let mut loot = Lootr::default();

let weapons = loot.add_branch("weapons", Lootr::default());
let armor = loot.add_branch("armor", Lootr::default());

Optionnaly with items

use lootr::{Lootr, item::Item};
let mut loot = Lootr::default();

loot.add_branch("weapons", Lootr::from(vec![
    Item::a("Staff"),
    Item::an("Uzi")
]));

loot.add_branch("armor", Lootr::from(vec![
    Item::a("Boots"),
    Item::a("Socks")
]));

loot.branch_mut("armor")
    .unwrap()
    .add_branch("leather", Lootr::from(vec![
        Item::a("Belt"),
        Item::a("Hat")
    ]));

Looting

Loot against a loot table, described by a like the following.

use lootr::{ROOT, drops::Drop};

let drops = [
    Drop { path: ROOT, depth: 1, luck: 1.0, stack: 1..=1, modify: false },
];

A builder pattern is also available to ease drops creation.

• path() selects the root of this drop
• depth() max depth to consider
• luck() the luck we start with, will decrease at each sub tree
• stack() the range of copies to yield

use lootr::{Lootr, item::Item, drops::DropBuilder};
let mut loot = Lootr::default();

loot.add_branch("weapons", Lootr::from(vec![
    Item::a("Staff"),
    Item::an("Uzi")
]));

loot.add_branch("armor", Lootr::from(vec![
    Item::a("Boots"),
    Item::a("Socks")
]));

let drops = [
    DropBuilder::new()
        .path("armor")
        .luck(1.0)
        .build(),

    DropBuilder::new()
        .path("weapons")
        .luck(1.0)
        .stack(1..=3)
        .build(),
];

// Loot your reward from a dead monster
let rewards = loot.loot(&drops);

// rewards = [ "Berries", "Plates", "Uzi", "Uzi", "Staff" ]

Modifiers

The library includes a basic modifiers system.

Add some modifiers to affect the properties of each looted item with addModifiers.

• name modifier will be used as simple suffixes. Or, if it contains one or more $property, each property name will be replaced.
• other properties will be handled as the following

loot.add({ name: "Staff", color: "golden" })
loot.addModifiers([
    { name:    "from the shadows" },
    { name:    "A $color $name from the gods" },
    { agility: 5 },
    { force:   "*2" },
    { intell:  "2-10" },
    { name:    "A $color $name from the gods", force: "+4" }
])

Then, at loot time:

deadMonster.drops = [
    {from: "/equipment", stack:2, modify:true }
]

// Loot your reward from a dead monster
var rewards = loot.loot(deadMonster.drops)

rewards = [
    // some of these could drop
    {name:"Staff from the shadows"},
    {name:"Staff", intell: 6},
    {name:"A golden staff from the gods"},
    {name:"A golden staff from the gods", force:4 }
]

Tests

cargo test