3 files changed, 49 insertions(+), 1 deletions(-)

A crates/unified/src/client/interpolation.rs
M crates/unified/src/client/mod.rs
M crates/unified/src/client/parts.rs

@@ 0,0 1,38 @@
+use std::time::{Duration};
+use avian2d::parry::transformation::utils::transform;
+use crate::prelude::*;
+
+pub fn interpolation_plugin(app: &mut App) {
+    app
+        .add_systems(Update, update_interpolation_info)
+        .add_systems(Update, do_interpolation);
+}
+
+#[derive(Component, Debug)]
+pub struct TransformInterpolationInfo {
+    pub last_dt: Duration,
+    pub this_tick_start: bevy::platform::time::Instant,
+    pub latest_transform: Transform,
+    pub last_transform: Transform,
+}
+
+fn update_interpolation_info(
+    mut interpolation_query: Query<(&Transform, &mut TransformInterpolationInfo), Changed<Transform>>,
+    time: Res<Time>,
+) {
+    for (transform, mut info) in interpolation_query.iter_mut() {
+        info.last_dt = info.this_tick_start.elapsed();
+        info.this_tick_start = bevy::platform::time::Instant::now();
+        info.last_transform = info.latest_transform;
+        info.latest_transform = transform.clone();
+    }
+}
+fn do_interpolation(
+    mut interpolation_query: Query<(&mut Transform, &TransformInterpolationInfo)>,
+) {
+    for (mut transform, info) in &mut interpolation_query {
+        let dt = bevy::platform::time::Instant::now() - info.this_tick_start;
+        let progress = dt.as_secs_f32() / info.last_dt.as_secs_f32(); // should be between 0.0 and 1.0
+        transform.bypass_change_detection().translation = info.last_transform.translation + progress * (info.latest_transform.translation - info.last_transform.translation);
+    }
+}<
\ No newline at end of file

@@ 42,6 42,7 @@ use std::rc::Rc;
 use wasm_bindgen::JsCast;
 #[cfg(target_arch = "wasm32")]
 use wasm_bindgen_futures::JsFuture;
+use crate::client::interpolation::interpolation_plugin;
 use crate::shared::config::planet::Planet;
 
 pub mod colors;


@@ 58,6 59,7 @@ pub mod starguide;
 pub mod crafting;
 pub mod components;
 pub mod plugins;
+mod interpolation;
 
 pub struct ClientPlugin {
     pub server: Option<String>


@@ 81,6 83,7 @@ impl Plugin for ClientPlugin {
             .add_plugins(starguide_input_plugin)
             //.add_plugins(starguide_orbit_plugin)
             .add_plugins(crafting_ui_plugin)
+            .add_plugins(interpolation_plugin)
             .add_systems(Update, find_me)
             .insert_state(GameplayState::Main)
             .insert_resource(DebugPickingMode::Disabled)

@@ 1,5 1,5 @@
 use std::f32::consts::PI;
-
+use std::time::Duration;
 use crate::shared::attachment::{Joint, JointOf, Joints, PartInShip, Peer, SnapOf, SnapOfJoint};
 use crate::client::crafting::ui::open_crafting_ui;
 use crate::shared::ecs::Temperature;


@@ 11,6 11,7 @@ use crate::client::components::Me;
 use crate::client::ship::attachment::AttachmentDebugRes;
 use crate::prelude::*;
 use bevy_replicon::client::confirm_history::ConfirmHistory;
+use crate::client::interpolation::TransformInterpolationInfo;
 
 pub fn parts_plugin(app: &mut App) {
     app.insert_resource(DragResource { dragged: None });


@@ 59,6 60,12 @@ fn handle_incoming_parts(
             .insert(MAIN_LAYER)
             .insert(sprite)
             .insert(Pickable::default())
+            .insert(TransformInterpolationInfo {
+                last_dt: Duration::from_millis(50), // assume it was 20tps because we don't know
+                this_tick_start: bevy::platform::time::Instant::now(),
+                latest_transform: transform.clone(),
+                last_transform: transform.clone(),
+            })
             .observe(on_part_click)
             .observe(open_crafting_ui);
     }