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use crate::Event;
#[derive(Debug, Default, Clone, Copy, PartialEq, Eq)]
pub struct Modifiers {
pub ctrl: bool,
pub alt: bool,
pub shift: bool,
pub logo: bool,
}
#[derive(Debug, Clone)]
pub struct Keyboard<Key, Mods>
where
Key: Copy + PartialEq,
Mods: Copy + Default,
{
modifiers: Mods,
keys_down: Vec<Key>,
keys_pressed: Vec<Key>,
keys_released: Vec<Key>,
}
impl<Key, Mods> Default for Keyboard<Key, Mods>
where
Key: Copy + PartialEq,
Mods: Copy + Default,
{
fn default() -> Self {
Keyboard {
modifiers: Default::default(),
keys_down: Vec::with_capacity(4),
keys_pressed: Vec::with_capacity(4),
keys_released: Vec::with_capacity(4),
}
}
}
impl<Key, Mods> Keyboard<Key, Mods>
where
Key: Copy + PartialEq,
Mods: Copy + Default,
{
pub fn new() -> Self {
Default::default()
}
pub fn modifiers(&self) -> Mods {
self.modifiers
}
pub fn begin_frame_input(&mut self) -> KeyboardInput<Key, Mods> {
self.keys_pressed.clear();
self.keys_released.clear();
KeyboardInput { keyboard: self }
}
pub fn down(&self, key: Key) -> bool {
self.keys_down.iter().any(|&k| k == key)
}
pub fn pressed(&self, key: Key) -> bool {
self.keys_pressed.iter().any(|&k| k == key)
}
pub fn released(&self, key: Key) -> bool {
self.keys_released.iter().any(|&k| k == key)
}
}
pub struct KeyboardInput<'a, Key, Mods>
where
Key: Copy + PartialEq + 'a,
Mods: Copy + Default + 'a,
{
keyboard: &'a mut Keyboard<Key, Mods>,
}
impl<'a, Key, Mods> KeyboardInput<'a, Key, Mods>
where
Key: Copy + PartialEq,
Mods: Copy + Default,
{
pub fn press(&mut self, key: Key) -> &mut Self {
if !self.keyboard.down(key) {
self.keyboard.keys_down.push(key);
}
if !self.keyboard.pressed(key) {
self.keyboard.keys_pressed.push(key);
}
self
}
pub fn release(&mut self, key: Key) -> &mut Self {
self.keyboard.keys_down.retain(|&k| k != key);
if !self.keyboard.released(key) {
self.keyboard.keys_released.push(key);
}
self
}
pub fn set_modifiers(&mut self, modifiers: Mods) -> &mut Self {
self.keyboard.modifiers = modifiers;
self
}
pub fn handle_event<E: Event<Self>>(&mut self, event: &E) -> &mut Self {
event.handle(self);
self
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn key_not_pressed_or_released_by_default() {
let keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
assert!(!keyboard.down(10));
assert!(!keyboard.pressed(10));
assert!(!keyboard.released(10));
}
#[test]
fn key_down_when_pressed() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().press(10);
}
assert!(keyboard.down(10));
}
#[test]
fn key_not_down_when_released() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().press(10).release(10);
}
assert!(!keyboard.down(10));
}
#[test]
fn key_pressed_after_pressing() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().press(10);
}
assert!(keyboard.pressed(10));
}
#[test]
fn key_released_after_releasing() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().release(10);
}
assert!(keyboard.released(10));
}
#[test]
fn key_can_be_pressed_and_released_on_same_frame() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().press(10).release(10);
}
assert!(keyboard.pressed(10));
assert!(keyboard.released(10));
}
#[test]
fn key_pressed_resets_at_start_of_frame() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().press(10);
}
{
keyboard.begin_frame_input();
}
assert!(!keyboard.pressed(10));
}
#[test]
fn key_released_resets_at_start_of_frame() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().release(10);
}
{
keyboard.begin_frame_input();
}
assert!(!keyboard.pressed(10));
}
#[test]
fn key_down_persists_across_frames() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().press(10);
}
{
keyboard.begin_frame_input();
}
assert!(keyboard.down(10));
}
#[test]
fn modifiers_empty_by_default() {
let keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
assert_eq!(keyboard.modifiers(), Modifiers::default());
}
#[test]
fn can_set_modifiers() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().set_modifiers(Modifiers {
ctrl: true,
alt: true,
shift: true,
logo: true,
});
}
assert_eq!(
keyboard.modifiers(),
Modifiers {
ctrl: true,
alt: true,
shift: true,
logo: true,
}
)
}
#[test]
fn modifiers_persisit_over_frames() {
let mut keyboard: Keyboard<usize, Modifiers> = Keyboard::new();
{
keyboard.begin_frame_input().set_modifiers(Modifiers {
ctrl: true,
alt: true,
shift: true,
logo: true,
});
}
{
keyboard.begin_frame_input();
}
assert_eq!(
keyboard.modifiers(),
Modifiers {
ctrl: true,
alt: true,
shift: true,
logo: true,
}
)
}
}