precalculate track + arc helper fn + structs

src/states/linear/components_track.rs

@@ -1,17 +1,53 @@
 use bevy::prelude::*;
 
-#[derive(Component)]
+#[derive(Resource)]
-pub struct Track{
+pub struct Track {
     pub start_point: Vec2,
     pub start_direction: Vec2, // будет нормализовано при построении
     pub segments: Vec<PathSegment>,
 }
 
+#[derive(Debug)]
+pub enum SegementType{
+    Line,
+    Turn,
+}
+
 // линия всегда строится от точки старта по направлению
 // направление изменяется сегментами поворота
 // left при истине - поворот против часовой стрелки, ложь - по часовой
 #[derive(Clone, Copy)]
-pub enum PathSegment{
+pub enum PathSegment {
     Line { length: f32 },
     Turn { radius: f32, left: bool },
+    // TODO заменить перечисление на структуру с полем типа SegementType, чтоб был единый источник типа
+}
+
+
+
+#[derive(Resource)]
+pub struct PrecalculatedTrack{
+    pub segments: Vec<PTSegment>
+}
+
+#[derive(Debug)]
+pub struct PTSegment {
+    pub t_start: f32,
+    pub t_end: f32,
+    pub segment_type: SegementType,
+    pub start_pos: Vec2,
+    pub direction: Vec2,
+    pub center: Vec2,
+    pub radius: f32,
+    pub start_angle: f32,
+    pub sweep_sign: f32,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct ArcCalculation {
+    pub normal: Vec2,
+    pub center: Vec2,
+    pub start_angle: f32,
+    pub sweep_sign: f32,
+    pub end_pos: Vec2,
 }

src/states/linear/plugin.rs

@@ -1,5 +1,6 @@
 use bevy::prelude::*;
 use crate::states::AppState::LinearState;
+use crate::states::level::GameOver;
 use crate::states::linear::*;
 
 pub struct LinearPlugin;
@@ -7,16 +8,26 @@ pub struct LinearPlugin;
 impl Plugin for LinearPlugin {
     fn build(&self, app: &mut App) {
         app
-            .add_systems(OnEnter (LinearState), (setup, setup_linear_track).chain())
+            .add_systems(OnEnter (LinearState), setup)
             .add_systems(Update, (draw_track_gizmos).run_if(in_state(LinearState)))
             .add_systems(OnExit (LinearState), cleanup);
     }
 }
 
-fn setup(mut commands: Commands) {}
+fn setup(mut commands: Commands) {
+    let build_track = setup_linear_track();
+    let precalculated_track = precalculate_track(&build_track);
+    
+    commands.insert_resource(build_track);
+    commands.insert_resource(precalculated_track);
+}
 
 fn cleanup(mut commands: Commands, query: Query<Entity, With<LinearStateMarker>>) {
+    // зачищаем сущности
     for entity in query.iter() {
         commands.entity(entity).despawn();
     }
+
+    // зачищаем ресурсы по типу
+    commands.remove_resource::<Track>();
 }

src/states/linear/systems.rs

@@ -1,15 +1,13 @@
 use crate::states;
 use bevy::prelude::*;
 use states::linear::*;
-use std::f32::consts::{FRAC_PI_2, PI};
+use std::f32::consts::FRAC_PI_2;
 
 const PINK: Color = Color::srgb_u8(250, 0, 155);
 const BLUE: Color = Color::srgb_u8(0, 0, 255);
 const GREEN: Color = Color::srgb_u8(0, 255, 0);
 
-pub fn draw_track_gizmos(query: Query<&Track>, mut gizmos: Gizmos) {
+pub fn draw_track_gizmos(track: Res<Track>, mut gizmos: Gizmos) {
-    println!("Рисуем трек из примитивов");
-    for track in &query {
     let mut current_pos = track.start_point;
     let mut current_dir = track.start_direction.normalize();
 
@@ -26,35 +24,20 @@ pub fn draw_track_gizmos(query: Query<&Track>, mut gizmos: Gizmos) {
             }
 
             PathSegment::Turn { radius, left } => {
-                    // вычисляем направление поворота и знак для угла
+                // вычисляем нормаль, центр, угол поворота арки и знак
-                    let (normal, sign): (Vec2, f32) = if *left {
+                let arc = helper_arc_calculator(current_pos, current_dir, *left, *radius);
-                        (Vec2::new(-current_dir.y, current_dir.x), -1.0)
-                    } else {
-                        (Vec2::new(current_dir.y, -current_dir.x), 1.0)
-                    };
-                    
-                    let center = current_pos + normal * radius;
-                    let start_vec = current_pos - center;
-                    let initial_vec = if *left {
-                        -start_vec.perp()
-                    } else {
-                        -start_vec
-                    };
 
                 gizmos.arc_2d(
-                        Isometry2d::new(center, Rot2::radians(initial_vec.to_angle())),
+                    Isometry2d::new(arc.center, Rot2::radians(arc.start_angle)),
                     FRAC_PI_2,
                     *radius,
                     GREEN,
                 );
-                    // current_pos = center + current_dir * radius;
+                current_pos = arc.end_pos;
-                    // current_pos = center + normal.perp() * radius;
+                current_dir = arc.normal;
-                    current_pos = center + normal.perp() * radius * sign;
-                    current_dir = normal;
             }
         }
     }
     // рисуем финиш
     gizmos.circle_2d(current_pos, 5.0, Color::WHITE);
-    }
 }

src/states/linear/systems_track.rs

@@ -1,6 +1,8 @@
+use std::f32::consts::FRAC_PI_2;
 use crate::states::linear::*;
-use crate::{FACTOR, HEIGHT, WIDTH};
+use crate::{FACTOR};
 use bevy::prelude::*;
+use bevy::reflect::List;
 
 pub const CENTER_X: f32 = 0.0;
 pub const CENTER_Y: f32 = 0.0;
@@ -11,10 +13,8 @@ pub const STEP: f32 = FACTOR as f32 / SCALE;
 pub const SCALE: f32 = 2.0;
 
 
-pub fn setup_linear_track(mut commands: Commands) {
+pub fn setup_linear_track() -> Track {
     println!("Построение трека начато");
-
-    commands.spawn((
         Track {
             start_point: Vec2 {
                 x: CENTER_X - FACTOR as f32 * 7.0,
@@ -22,23 +22,120 @@ pub fn setup_linear_track(mut commands: Commands) {
             },
             start_direction: Vec2::X,
             segments: vec![
-                PathSegment::Line { length: STEP * 2.0 },
+                PathSegment::Line { length: STEP * 6.0 },
                 PathSegment::Turn { radius: STEP, left: true },
                 PathSegment::Line { length: STEP },
                 PathSegment::Turn { radius: STEP, left: false },
-                PathSegment::Line { length: STEP * 10.0 },
+                PathSegment::Line { length: STEP * 18.0 },
                 PathSegment::Turn { radius: STEP, left: true },
                 PathSegment::Line { length: STEP * 4.0 },
                 PathSegment::Turn { radius: STEP, left: true },
                 PathSegment::Turn { radius: STEP, left: false },
+                PathSegment::Line { length: STEP * 4.0 },
+                PathSegment::Turn { radius: STEP, left: true },
+                PathSegment::Line { length: STEP * 20.0 },
+                PathSegment::Turn { radius: STEP, left: true },
+                PathSegment::Line { length: STEP * 5.0 },
+                PathSegment::Turn { radius: STEP, left: true },
+                PathSegment::Line { length: STEP * 10.0 },
+                PathSegment::Turn { radius: STEP, left: false },
                 PathSegment::Line { length: STEP * 2.0 },
-                PathSegment::Turn { radius: STEP, left: true },
-                PathSegment::Line { length: STEP * 6.0 },
-                PathSegment::Turn { radius: STEP, left: true },
-                PathSegment::Line { length: STEP * 1.0 },
-                PathSegment::Turn { radius: STEP, left: true },
             ],
-        },
+        }
-        LinearStateMarker,
+}
-    ));
+
+pub fn precalculate_track(track: &Track) -> PrecalculatedTrack {
+    let mut pt = PrecalculatedTrack { segments: vec![] };
+    let mut cumulative_length: Vec<f32> = vec![0.0];
+
+    let mut current_pos = track.start_point;
+    let mut current_dir = track.start_direction;
+    
+    // на первом проходе заполняем все, кроме t_start и t_end,
+    // потому что мы не можем посчитать их без общей длины
+    for seg in track.segments.iter(){
+        match seg {
+            PathSegment::Line { length } => {
+                let calc_seg = PTSegment {
+                    t_start: 0.0,
+                    t_end: 0.0,
+                    segment_type: SegementType::Line,
+                    start_pos: current_pos,
+                    direction: current_dir,
+                    center: Vec2::ZERO,
+                    radius: 0.0,
+                    start_angle: 0.0,
+                    sweep_sign: 0.0,
+                };
+
+                pt.segments.push(calc_seg);
+                // сдвигаем позицию для следующего сегмента
+                current_pos = current_pos + length * current_dir;
+                // направление не меняем, пропуск
+                // накапливаем длину
+                cumulative_length.push(cumulative_length[cumulative_length.len() -1] + *length);
+            }
+
+            PathSegment::Turn {radius, left } => {
+                let arc = helper_arc_calculator(current_pos, current_dir, *left, *radius);
+                
+                let calc_seg = PTSegment {
+                    t_start: 0.0,
+                    t_end: 0.0,
+                    segment_type: SegementType::Turn,
+                    start_pos: current_pos,
+                    direction: current_dir,
+                    center: arc.center,
+                    radius: *radius,
+                    start_angle: arc.start_angle,
+                    sweep_sign: arc.sweep_sign,
+                };
+                pt.segments.push(calc_seg);
+                // сдвигаем позицию для следующего сегмента
+                current_pos = arc.end_pos;
+                current_dir = arc.normal;
+                // накапливаем длину
+                cumulative_length.push(cumulative_length[cumulative_length.len() -1] + (FRAC_PI_2 * radius));
+            }
+        }
+    }
+    
+    let last_index = cumulative_length.len() - 1;
+    let total_length = cumulative_length[last_index];
+    
+    // итерируемся уже по прекалькулированному вектору
+    // заполняем точки на треке в пересчете на общую длину
+    println!("Precalculated track:");
+    for (i, seg) in pt.segments.iter_mut().enumerate() {
+        seg.t_start = cumulative_length[i] / total_length;
+        if i < last_index {
+            seg.t_end = cumulative_length[i+1] / total_length;
+        } else {
+            seg.t_end = 1.0;
+        }
+        println!("{:?}", seg);
+    }
+    
+    pt
+}
+
+pub fn helper_arc_calculator(pos: Vec2, dir: Vec2, turn_to: bool, radius: f32) -> ArcCalculation{
+    let (normal, sign): (Vec2, f32) = if turn_to {
+        (Vec2::new(-dir.y, dir.x), -1.0)
+    } else {
+        (Vec2::new(dir.y, -dir.x), 1.0)
+    };
+
+    let center = pos + normal * radius;
+    let start_vec = pos - center;
+    let initial_vec = if turn_to { -start_vec.perp() } else { -start_vec };
+    let angle = initial_vec.to_angle();
+    
+    ArcCalculation{
+        normal,
+        center,
+        start_angle: angle,
+        sweep_sign: sign,
+        end_pos: center + normal.perp() * radius * sign,
+    }
 }