game_stat

game_stat is a small Rust library for handling stats that can change with modifiers. Equipped an epic sword? Then your attack stats could increase by 40. Received a debuff? Your movement speed could decrease by 50%.

Example code

let mut armor_stat: Stat<2> = Stat::new(10f32);
{
    let _modifier_handle = armor_stat.add_modifier(StatModifier::Flat(5f32));
    println!("armor_stat is: {} it should be 15!", armor_stat.value());
}
println!("armor_stat is: {}, It should be 10!", armor_stat.value());

This code creates a Stat<2>, meaning it can hold a maximum of 2 modifiers (a design decision explained later).
armor_stat.value() returns our stat value based on what modifiers are active.
We add a flat modifier, it is valid as long as the _modifier_key exists, which is why our value goes back to 10 when it gets dropped from the stack.

Features

Say goodbye to stat.remove_modifier(). This library has no such feature, instead a modifier is valid as long as a handle to it exists. It's a cool idea, but I don't know yet if this design choice will be practical.
Everything lives on the stack. (blessing or curse, you tell me... I just wanted to experiment with const generics). This is achieved by stating in stat creation what the max modifier count is Stat<4>.
Customizable Modifier order (optional), some games might require a more customizable Modifier application, use stat.add_modifier_with_order() instead of stat.add_modifier().

Is it battle ready?

I have not used this library in any real project yet. My design choices sounds good on paper, but is it useful? Time will tell.

API design goals

Tiny, laser focused. no external dependencies (except for std)

License

gamestat is free and open source! All code in this repository is dual-licensed under either:

MIT License (LICENSE-MIT or http://opensource.org/licenses/MIT)
Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)

at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

sclausen / game_stat