A fast and simple zig native ECS.
Builds against zig 0.11.0+
Define your components in a container
const std = @import("std");
const ecs = @import("coyote-ecs");
const World = ecs.World;
const Cast = ecs.Cast;
const Systems = ecs.Systems;
//Container name is configured in ECS constants
pub const Components = struct {
pub const Apple = struct {
color: u32 = 0,
ripe: bool = false,
harvested: bool = false,
};
pub const Orange = struct {
color: u32 = 0,
ripe: bool = false,
harvested: bool = false,
};
};Create some entities and components in a world
pub fn main() !void {
//Create a world
var world = try World.create();
defer world.deinit();
//Create an entity
var anOrange = try world.entities.create();
var anApple = try world.entities.create();
std.log.info("Created an Orange ID: {}", .{anOrange.id});
//Create a unique component
var orangeComponent = try world.components.create(Components.Orange);
var appleComponent = try world.components.create(Components.Apple);
//Attach and assign a component. Do not use an anonymous struct.
try anOrange.attach(orangeComponent, Components.Orange{.color = 0, .ripe = false, .harvested = false});
try anApple.attach(appleComponent, Components.Apple{.color = 0, .ripe = false, .harvested = false});
//Create 1k entities and attach 1k unique components
var i: usize = 0;
while(i < 1000) : (i += 1) {
var anEntity = try world.entities.create();
var anOrangeComponent = try world.components.create(Components.Orange);
try anEntity.attach(anOrangeComponent, Components.Orange{.color = 1, .ripe = false, .harvested = false});
}
//Filter components by type
var it = world.components.iteratorFilter(Components.Orange);
i = 0;
while(it.next()) |_| : (i += 1) {
//...
}
std.log.info("Orange components: {}", .{i});
//Filter entities by type
var it2 = world.entities.iteratorFilter(Components.Apple);
i = 0;
while(it2.next()) |_| : (i += 1) {
//...
}
std.log.info("Apple entities: {}", .{i});
try Systems.run(Grow, .{world});
try Systems.run(Harvest, .{world});
try Systems.run(Raze, .{world});
std.log.info("Entities: {}", .{world.entities.count()});
std.log.info("Components: {}", .{world.components.count()});
}Create some systems
pub fn Grow(world: *World) void {
var it = world.components.iterator();
var i: u32 = 0;
while(it.next()) |component| : (i += 1) {
if(component.is(Components.Orange)) {
try component.set(Components.Orange, .{.ripe = true});
}
if(component.is(Components.Apple)) {
try component.set(Components.Apple, .{.ripe = true});
}
//Fruits fall from the tree
component.detach();
}
std.log.info("Fruits grown: {}", .{i});
}
pub fn Harvest(world: *World) void {
var it = world.components.iterator();
var i: u32 = 0;
wh
5FAC
ile(it.next()) |component| {
if(component.is(Components.Orange)) {
if(Cast(Components.Orange).get(component).ripe == true) {
try component.set(Components.Orange, .{.harvested = true});
i += 1;
}
}
if(component.is(Components.Apple)) {
if(Cast(Components.Apple).get(component).ripe == true) {
try component.set(Components.Apple, .{.harvested = true});
i += 1;
}
}
component.destroy();
}
std.log.info("Fruits harvested: {}", .{i});
}
pub fn Raze(world: *World) void {
var it = world.entities.iterator();
var i: u32 = 0;
while(it.next()) |entity| {
entity.destroy();
i += 1;
}
std.log.info("Entities destroyed: {}", .{i});
}