zest_core/
event.rs

1//! Runtime input and output events.
2
3use embedded_graphics::prelude::*;
4
5/// State of a non-touch button-like input.
6#[derive(Copy, Clone, Debug, PartialEq, Eq)]
7pub enum ButtonState {
8    /// The input was pressed.
9    Pressed,
10    /// The input was released.
11    Released,
12    /// The input repeated while held.
13    Repeated,
14}
15
16/// Keyboard key identifier.
17#[derive(Copy, Clone, Debug, PartialEq, Eq)]
18pub enum Key {
19    /// Printable character input.
20    Char(char),
21    /// Enter / return.
22    Enter,
23    /// Escape / back.
24    Escape,
25    /// Tab.
26    Tab,
27    /// Backspace.
28    Backspace,
29    /// Delete.
30    Delete,
31    /// Left arrow.
32    Left,
33    /// Right arrow.
34    Right,
35    /// Up arrow.
36    Up,
37    /// Down arrow.
38    Down,
39    /// Home.
40    Home,
41    /// End.
42    End,
43    /// Page up.
44    PageUp,
45    /// Page down.
46    PageDown,
47}
48
49/// Keyboard input delivered to screens.
50#[derive(Copy, Clone, Debug, PartialEq, Eq)]
51pub struct KeyEvent {
52    /// Which key changed.
53    pub key: Key,
54    /// Press/release/repeat state.
55    pub state: ButtonState,
56}
57
58/// Rotary encoder step input.
59#[derive(Copy, Clone, Debug, PartialEq, Eq)]
60pub struct EncoderEvent {
61    /// Signed step delta. Positive and negative directions are backend-defined.
62    pub delta: i32,
63}
64
65/// Semantic UI action independent of any particular hardware input.
66#[derive(Copy, Clone, Debug, PartialEq, Eq)]
67pub enum UiAction {
68    /// Activate the focused control.
69    Activate,
70    /// Cancel, dismiss, or go back.
71    Cancel,
72    /// Move focus forward.
73    FocusNext,
74    /// Move focus backward.
75    FocusPrevious,
76    /// Increase a value or move right/down in a control-specific way.
77    Increment,
78    /// Decrease a value or move left/up in a control-specific way.
79    Decrement,
80    /// Move focus or selection left.
81    NavigateLeft,
82    /// Move focus or selection right.
83    NavigateRight,
84    /// Move focus or selection up.
85    NavigateUp,
86    /// Move focus or selection down.
87    NavigateDown,
88    /// Open a surface such as a dropdown or menu.
89    Open,
90    /// Close a surface such as a dropdown or menu.
91    Close,
92}
93
94/// Touch event delivered to screens.
95///
96/// Re-exported so apps don't need a separate crate for the touch type.
97/// Apps that already have their own `TouchEvent` (e.g. from a touch driver
98/// crate) can implement `From` into this one.
99#[derive(Copy, Clone, Debug, PartialEq, Eq)]
100pub struct TouchEvent {
101    /// Screen-space coordinates of the touch.
102    pub point: Point,
103    /// Whether this is a touch-down, ongoing, or release.
104    pub phase: TouchPhase,
105}
106
107/// Phase of a touch event.
108#[derive(Copy, Clone, Debug, PartialEq, Eq)]
109pub enum TouchPhase {
110    /// Finger just landed on the screen.
111    Down,
112    /// Finger is still on the screen (moved).
113    Moved,
114    /// Finger left the screen.
115    Up,
116}
117
118/// Input from the platform main loop into the [`Runtime`](crate::runtime::Runtime).
119#[derive(Copy, Clone, Debug, PartialEq, Eq)]
120pub enum InputEvent {
121    /// A touch event.
122    Touch(TouchEvent),
123    /// A key event.
124    Key(KeyEvent),
125    /// A rotary encoder event.
126    Encoder(EncoderEvent),
127    /// A semantic UI action.
128    Action(UiAction),
129}
130
131/// What the runtime did this tick, instructing the platform main loop on
132/// next steps.
133#[derive(Copy, Clone, Debug, PartialEq, Eq)]
134pub enum TickResult {
135    /// Nothing changed; the platform can sleep until the next event.
136    Idle,
137    /// Visual changed; redraw and flush.
138    NeedsRedraw,
139    /// Layout changed (and so the visual); a full layout + draw pass is
140    /// required. The runtime handles this internally; the platform just
141    /// needs to redraw and flush.
142    NeedsLayout,
143}
144
145impl TickResult {
146    /// True iff the runtime wants the platform to call `draw` this tick.
147    #[must_use]
148    pub fn wants_draw(self) -> bool {
149        matches!(self, Self::NeedsRedraw | Self::NeedsLayout)
150    }
151}
zest_core/event.rs

zest_core/
event.rs
