Bevy UI layout (docs-first stub)
Not a full port. Docs-first stub. Godot counterpart: godot-ui-containers.
When to use
Load this when laying out HUD or menu nodes. Text content stays on bevy-ui-text. Colors and widget styling stay on bevy-ui-theming.
ECS shape
- Crate text (opened): spawn UI with
widget::Button,ImageNode,Text, andNode. Layout uses Flexbox and CSS Grid. - Components named:
Node,BackgroundColor,BorderColor,BorderRadius,ComputedNode,GridPlacement,GridTrack,GlobalZIndex. - Feature:
bevy_uiis a custom ECS-driven UI framework. - Systems: layout and update systems are engine-owned (
bevy::ui::updateexists). Do not write a second layout pass.
Godot idea to Bevy idiom
| Idea | Bevy idiom (idea only) |
|---|---|
| Container | A Node entity. Children are child entities, not Control nodes. |
| Button | widget::Button as named in the crate summary. |
| Image | ImageNode as named in the crate summary. |
| Grid | GridTrack and GridPlacement. |
Gaps
- Flex property field names on
Nodewere not opened. Do not inventjustify_contentspellings. bevy_feathersis a styled widget collection for editors. Its widget list was not opened. Do not treat it as game HUD theme.
Expert Knowledge Delta
Library target in prose: Bevy 0.20.0. Lattice URLs stay unversioned.
Opened canon only: Component, Resource, Query, Commands, Startup, Update, Fixed / FixedMain (bevy::time), .chain(), Plugin, DefaultPlugins, MinimalPlugins. Messages and observers are an ownership slot. This file does not invent their struct APIs. Systems run in parallel unless .chain() orders the ones that conflict.
Who owns state
| Piece | Owner | Who may mutate | Schedule |
|---|---|---|---|
| Data on one entity | Component | One system via Query | Update or FixedMain |
| One value for the whole app | Resource | One system | Startup to insert, then the schedule that reads it |
| Spawn | Commands | The spawning system | Startup for the initial world; later schedules for runtime spawn |
| Order that must not race | .chain() | The chained systems only | Same schedule |
| Plugin boundary | Plugin | build registers systems and resources | Before the app runs |
Borrow rule: two systems that both mutably query the same component must be ordered (.chain()) or split so only one writes. Unrelated systems stay parallel. That is the ECS page rule, not a guess at a system-set API.
Decision
| If you need | Do this | Do not |
|---|---|---|
| Per-entity data | Component + Query | A Godot node script |
| App-wide config or clock | Resource | Copy the value onto every entity |
| Stable simulation step | FixedMain and the Fixed clock | Tie simulation to raw frame Update |
| Startup spawn | Commands in Startup | Spawn from a render system |
| Cross-system notice that is not shared state | Message or observer slot in bevy-events-messaging | A new event type invented in this file |
| An API this skill did not open | A Gaps row | A fabricated crate (solver, navmesh module, net, XR) |
Load references/a-gate-notes.md for the same table plus the gap rule.
NEVER
-
Do not put
/0.20.0/in lattice URLs. WHY: permalinks stay onlatest. The 0.20.0 pin belongs in prose once. -
Do not mutably query the same component from two unordered systems. WHY: the schedule runs systems in parallel unless
.chain()orders them. -
Do not invent a physics, navigation, networking, or XR crate here. WHY: those rows are gaps, blocked, or revisit.
-
No Godot Control, Container, or anchor types. WHY: a Godot port, an unopened API, or a public lie fails the docs-first bar.
-
No Godot types in Bevy code. WHY: a Godot port, an unopened API, or a public lie fails the docs-first bar.
-
No invented APIs or unnamed third-party crates as the chosen solver. WHY: a Godot port, an unopened API, or a public lie fails the docs-first bar.
-
No Creation Station content. WHY: a Godot port, an unopened API, or a public lie fails the docs-first bar.
-
No umbrella skill over Godot and Bevy. WHY: a Godot port, an unopened API, or a public lie fails the docs-first bar.
-
Do not mark this row
ported. It isdocs_mapped. WHY: a Godot port, an unopened API, or a public lie fails the docs-first bar.
Reference
docs.rs links use the unversioned latest permalink. The library pin on bevy-master stays 0.20.0.
Official Documentation
- Migration guides - Unversioned hop index.
- bevy crate - Unversioned API index. Feature list opened for 0.20.0.
- Assets - Official asset catalog. No third-party crate was selected.
- Examples - Example tree on the
latestbranch. - ECS -
Component, systems,Query,Startup,Update, and.chain(). - Plugins -
Plugin,DefaultPlugins,MinimalPlugins, andadd_plugins. - bevy::ui -
Node, Flexbox and CSS Grid,widget::Button,ImageNode,Text.
Related Skills
Prerequisites
- bevy-master - Hub and schedules.
- bevy-ecs-composition - Components and systems.
Complements
- bevy-ui-text - Text on a node.
- bevy-ui-theming - Colors and backgrounds.
- godot-ui-containers - Godot counterpart. Source idea only.
Downstream / consumers
- bevy-ui-text - Consumes layout nodes.
Master
- bevy-master - Bevy router.


