#stats #gamedev #modifier #change #increase #attack #epic

game_stat

a library for handling stats that can change with modifiers, most commonly seen in games

5 releases

0.2.2 May 29, 2023
0.2.1 May 29, 2023
0.2.0 May 29, 2023
0.1.1 Mar 15, 2022
0.1.0 Mar 13, 2022

#247 in Game dev

24 downloads per month

MIT/Apache

33KB
239 lines

Crates.io docs.rs MIT/Apache 2.0 Crates.io

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());
  • Stat<2> This library uses TinyVec internally to hold modifiers (for optimization). A value of 2 means we can hold 2 modifiers on the stack, if exceeded we'll internally move them to the heap.
  • 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_handle 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.
  • 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?

No major project has been completed with this yet. I'm not sure of it's stability/performance, considering I'm internally using mutex with sync feature enabled, and interior mutability. I'm currently testing this library for a tower defence game. Time will tell :)

License

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

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.

Dependencies

~200–440KB
~14K SLoC