Trait GraphicsFlow 

pub trait GraphicsFlow<S, E: Send> {
    // Provided methods
    fn on_init(&mut self, _ctx: &mut Context, _state: &mut S) -> Out<S, E> { ... }
    fn on_click(
        &mut self,
        _ctx: &Context,
        _state: &mut S,
        _id: PickId,
    ) -> Out<S, E> { ... }
    fn on_update(
        &mut self,
        _ctx: &Context,
        _state: &mut S,
        _dt: Duration,
    ) -> Out<S, E> { ... }
    fn on_tick(&mut self, _ctx: &Context, _state: &mut S) -> Out<S, E> { ... }
    fn on_device_events(
        &mut self,
        _ctx: &Context,
        _state: &mut S,
        _event: &DeviceEvent,
    ) -> Out<S, E> { ... }
    fn on_window_events(
        &mut self,
        _ctx: &Context,
        _state: &mut S,
        _event: &WindowEvent,
    ) -> Out<S, E> { ... }
    fn on_custom_events(
        &mut self,
        _ctx: &Context,
        _state: &mut S,
        event: E,
    ) -> Option<E> { ... }
    fn on_render<'pass>(&self) -> Render<'_, 'pass> { ... }
}

Trait for implementing a renderable scene or game state.

A GraphicsFlow manages a self-contained portion of the application: rendering, input handling, animations, and state updates. The engine coordinates multiple flows, passes events to them, and composes their renders.

Lifecycle

1. on_init() is called once when the flow is created; configure context (camera, clear color, etc.)
2. on_window_events() and on_device_events() are called for each winit input event
3. on_update() is called every frame
4. on_tick() is called every tick_duration_millis
5. on_click() is called when an object with this flow’s ID is clicked
6. on_custom_events() is called for custom application events
7. on_render() is called each frame and specifies how to render self

Provided Methods

fn on_init(&mut self, _ctx: &mut Context, _state: &mut S) -> Out<S, E>

Initialize the flow and configure the context.

This is the only place to modify the Context and configure things such as the default background colour or camera start position.

fn on_click(&mut self, _ctx: &Context, _state: &mut S, _id: PickId) -> Out<S, E>

Handle a click on an object rendered by this flow.

on_click is triggered when something on the screen (rendered by self) was clicked on.

id is the ID that correlates to a specific mesh set via on_render. It is advised to use a unique u32 id for each element that should be selectable

When the render type Custom is used then also picking has to be implemented by the caller. See flow_ngin::pick::draw_to_pick_buffer for more information about custom picking. picking; see [crate::pick::draw_to_pick_buffer] for details.

fn on_update( &mut self, _ctx: &Context, _state: &mut S, _dt: Duration, ) -> Out<S, E>

Update state every frame.

Called every frame with the elapsed time dt. Use for animations, physics updates, and other per-frame logic.

fn on_tick(&mut self, _ctx: &Context, _state: &mut S) -> Out<S, E>

Update state periodically.

Called every tick_duration_millis milliseconds (configurable via context). Use for discrete game logic that doesn’t need to run every frame.

fn on_device_events( &mut self, _ctx: &Context, _state: &mut S, _event: &DeviceEvent, ) -> Out<S, E>

Handle raw device events (keyboard, mouse hardware input).

fn on_window_events( &mut self, _ctx: &Context, _state: &mut S, _event: &WindowEvent, ) -> Out<S, E>

Handle window events (keyboard, mouse, window resizing, etc.).

fn on_custom_events( &mut self, _ctx: &Context, _state: &mut S, event: E, ) -> Option<E>

Handle custom application events.

Returns the event if it was not consumed, allowing it to be passed to the next flow. Returning None means the event was consumed.

fn on_render<'pass>(&self) -> Render<'_, 'pass>

Return renderable objects for this flow.

Called each frame. Collect your objects into a Render and return it. The engine will batch and render all flows’ renders in optimal order.

Trait Implementations

impl<State, Event> Debug for dyn GraphicsFlow<State, Event> + 'static

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

Implementors