examples/queries/
query_group_by.rs

1use crate::z_ignore_test_common::*;
2
3use flecs_ecs::prelude::*;
4
5#[derive(Debug, Component)]
6pub struct Position {
7    pub x: f32,
8    pub y: f32,
9}
10
11#[derive(Component)]
12pub struct Tag;
13
14#[derive(Component)]
15pub struct First;
16
17#[derive(Component)]
18pub struct Second;
19
20#[derive(Component)]
21pub struct Third;
22
23#[derive(Component)]
24pub struct Group;
25
26fn main() {
27    let world = World::new();
28
29    world.component::<First>();
30    world.component::<Second>();
31    world.component::<Third>();
32
33    let query = world.query::<&Position>().group_by(Group).build();
34
35    world
36        .entity()
37        .add((Group, Third))
38        .set(Position { x: 1.0, y: 1.0 });
39    world
40        .entity()
41        .add((Group, Second))
42        .set(Position { x: 2.0, y: 2.0 });
43    world
44        .entity()
45        .add((Group, First))
46        .set(Position { x: 3.0, y: 3.0 });
47
48    world
49        .entity()
50        .add((Group, Third))
51        .set(Position { x: 4.0, y: 4.0 })
52        .add(Tag);
53    world
54        .entity()
55        .add((Group, Second))
56        .set(Position { x: 5.0, y: 5.0 })
57        .add(Tag);
58    world
59        .entity()
60        .add((Group, First))
61        .set(Position { x: 6.0, y: 6.0 })
62        .add(Tag);
63
64    println!();
65
66    query.run(|mut it| {
67        while it.next() {
68            let group = world.entity_from_id(it.group_id());
69            let pos = it.field::<Position>(0);
70
71            println!(
72                "Group: {:?} - Table: [{:?}]",
73                group.path().unwrap(),
74                it.archetype()
75            );
76
77            for i in it.iter() {
78                println!(" [{:?}]", pos[i]);
79            }
80
81            println!();
82        }
83    });
84
85    // Output:
86    //  Group: "::First" - Table: [Position, (Group,First)]
87    //  [Position { x: 3.0, y: 3.0 }]
88    //
89    //  Group: "::First" - Table: [Position, Tag, (Group,First)]
90    //  [Position { x: 6.0, y: 6.0 }]
91    //
92    //  Group: "::Second" - Table: [Position, (Group,Second)]
93    //  [Position { x: 2.0, y: 2.0 }]
94    //
95    //  Group: "::Second" - Table: [Position, Tag, (Group,Second)]
96    //  [Position { x: 5.0, y: 5.0 }]
97    //
98    //  Group: "::Third" - Table: [Position, (Group,Third)]
99    //  [Position { x: 1.0, y: 1.0 }]
100    //
101    //  Group: "::Third" - Table: [Position, Tag, (Group,Third)]
102    //  [Position { x: 4.0, y: 4.0 }]
103}
104
105#[cfg(feature = "flecs_nightly_tests")]
106#[test]
107fn test() {
108    let output_capture = OutputCapture::capture().unwrap();
109    main();
110    output_capture.test("query_group_by".to_string());
111}
examples/queries/query_group_by.rs

examples/queries/
query_group_by.rs
