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use crate::types::{KeyCode, MouseButton};
use std::collections::VecDeque;
#[derive(Debug, Clone)]
pub struct InputSnapshot {
pub timestamp: f64,
// Store minimal state delta or full state? Full state is safer for now.
// To minimize allocations, we might want bitsets or simplified structures.
// For MVP, we'll store active keys/buttons.
pub active_keys: Vec<KeyCode>,
pub mouse_pos: (f32, f32),
pub mouse_buttons: Vec<MouseButton>,
// Gamepad state could be large, store simplified or just what changed?
// Let's store specific gamepad states if needed, skipping for MVP/focus on Mouse/Keyboard latency first
// usually Mouse is critical for FPS.
}
pub struct HighFrequencyInputPoller {
target_hz: u32,
samples: VecDeque<InputSnapshot>,
last_poll_time: f64,
}
impl HighFrequencyInputPoller {
pub fn new(target_hz: u32) -> Self {
Self {
target_hz,
samples: VecDeque::with_capacity((target_hz / 60) as usize * 2),
last_poll_time: 0.0,
}
}
pub fn target_interval(&self) -> f64 {
1.0 / self.target_hz as f64
}
pub fn should_poll(&self, current_time: f64) -> bool {
current_time - self.last_poll_time >= self.target_interval()
}
pub fn record_snapshot(&mut self, snapshot: InputSnapshot) {
self.samples.push_back(snapshot);
self.last_poll_time = self.samples.back().unwrap().timestamp;
// Keep buffer manageable (e.g. 1 second worth, or just last few frames?)
// Realistically we only need history for the current frame + maybe some prediction history
if self.samples.len() > 1000 {
self.samples.pop_front();
}
}
/// Retrieve inputs relevant for the current frame logic.
/// This could aggregate sub-frame moves (e.g. mouse delta accumulation).
pub fn get_aggregated_mouse_delta(&self, from_time: f64) -> (f32, f32) {
let mut delta_x = 0.0;
let mut delta_y = 0.0;
// Iterate relevant samples
// We assume samples are sorted by time.
// We find the first sample >= from_time
let mut previous_pos: Option<(f32, f32)> = None;
// Efficiently finding start index could be done with binary search if VecDeque supports it well or just linear scan from back
for sample in self.samples.iter() {
if sample.timestamp < from_time {
previous_pos = Some(sample.mouse_pos);
continue;
}
if let Some(prev) = previous_pos {
delta_x += sample.mouse_pos.0 - prev.0;
delta_y += sample.mouse_pos.1 - prev.1;
}
previous_pos = Some(sample.mouse_pos);
}
(delta_x, delta_y)
}
}