A general purpose grided entity library meant to support tilemap libraries, or other libraries that require accessing entities in a grid based manner built on top of the aery relations crate. The goal is to keep the API surface as simple and intuitive as possible, and to avoid deferred operations/states where possible to make the structures more intuitive work with (ex: an update in one system should be seen by the following system, not the following frame.).

Features

Currently, bevy_cells supports the following:

• Automatic chunking (including access to chunk entities)
• Automatic map creation
• Hierarchical despawning of chunks and maps
• N-dimensional map support
• Map based quiries
• Spatial queries
• Batched operations for better performance on large groups of cells or chunks

Upcoming features:

• Automatigically handle hierarchical deletes (via aery support or supported directly in this crate)
• Sort cells in memory based on chunk and map (will require bevy API additions in the future)

API

The basic API revolves around CellQuery's, CellCommands, and CellMapLabel's as seen below.

struct GameLayer;

impl CellMapLabel for GameLayer {
    const CHUNK_SIZE: usize = 16;
}

fn move_character(
    keyboard_input: Res<Input<KeyCode>>,
    mut commands: Commands,
    character: CellQuery<GameLayer, CellCoord, With<Character>>,
    walls: CellQuery<GameLayer, (), With<Block>>,
) {
    let mut cell_commands = commands.cells::<GameLayer, 2>();

    let mut x = if keyboard_input.just_pressed(KeyCode::A) {
        -1
    } else {
        0
    };

    x += if keyboard_input.just_pressed(KeyCode::D) {
        1
    } else {
        0
    };

    let char_c = character.single();
    let new_coord = [char_c[0] + x, char_c[1] + y];

    if walls.get_at(new_coord).is_none() {
        cell_commands.move_cell(*char_c, new_coord);
    }
}

More examples can be found in the examples folder!

Versions