Tweak many gizmos stress test

examples/stress_tests/many_gizmos.rs

@@ -1,3 +1,4 @@
+use std::cmp::max;
 use std::f32::consts::TAU;
 
 use bevy::{
@@ -30,8 +31,12 @@ fn main() {
     .add_systems(Startup, setup)
     .add_systems(Update, (input, ui_system));
 
-    for _ in 0..SYSTEM_COUNT {
-        app.add_systems(Update, system);
+    let make_system = |index: u32| {
+        move |config: Res<Config>, time: Res<Time>, draw: Gizmos| system(index, config, time, draw)
+    };
+
+    for index in 0..SYSTEM_COUNT {
+        app.add_systems(Update, make_system(index));
     }
 
     app.run();
@@ -45,30 +50,43 @@ struct Config {
 
 fn input(mut config: ResMut<Config>, input: Res<Input<KeyCode>>) {
     if input.just_pressed(KeyCode::Up) {
-        config.line_count += 10_000;
+        config.line_count = max((config.line_count as f32 * 1.2).ceil() as u32, 1);
     }
     if input.just_pressed(KeyCode::Down) {
-        config.line_count = config.line_count.saturating_sub(10_000);
+        config.line_count = (config.line_count as f32 / 1.2).floor() as u32;
     }
     if input.just_pressed(KeyCode::Space) {
         config.fancy = !config.fancy;
     }
 }
 
-fn system(config: Res<Config>, time: Res<Time>, mut draw: Gizmos) {
-    if !config.fancy {
-        for _ in 0..(config.line_count / SYSTEM_COUNT) {
-            draw.line(Vec3::NEG_Y, Vec3::Y, Color::BLACK);
-        }
+fn system(index: u32, config: Res<Config>, time: Res<Time>, mut draw: Gizmos) {
+    let mut rand_state = if !config.fancy {
+        index as i32
     } else {
-        for i in 0..(config.line_count / SYSTEM_COUNT) {
-            let angle = i as f32 / (config.line_count / SYSTEM_COUNT) as f32 * TAU;
+        (time.elapsed_seconds() as i32 as f32 * (index + 1) as f32) as i32
+    };
 
+    let mut rand = || -> f32 {
+        rand_state = rand_state.wrapping_mul(1103515245).wrapping_add(12345) & 0x7fffffff;
+        (rand_state as f32 / 0x3fffffff as f32) - 1.
+    };
+
+    let line_count =
+        config.line_count / SYSTEM_COUNT + (index < config.line_count % SYSTEM_COUNT) as u32;
+
+    for i in 0..line_count {
+        let start = Vec3::new(rand(), rand(), rand());
+        let end = Vec3::new(rand(), rand(), rand());
+
+        if !config.fancy {
+            draw.line(start, end, Color::WHITE);
+        } else {
+            let angle = (i * SYSTEM_COUNT + index) as f32 / config.line_count as f32 * TAU;
             let vector = Vec2::from(angle.sin_cos()).extend(time.elapsed_seconds().sin());
             let start_color = Color::rgb(vector.x, vector.z, 0.5);
             let end_color = Color::rgb(-vector.z, -vector.y, 0.5);
-
-            draw.line_gradient(vector, -vector, start_color, end_color);
+            draw.line_gradient(start, end, start_color, end_color);
         }
     }
 }
@@ -77,7 +95,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
     warn!(include_str!("warning_string.txt"));
 
     commands.spawn(Camera3dBundle {
-        transform: Transform::from_xyz(3., 1., 5.).looking_at(Vec3::ZERO, Vec3::Y),
+        transform: Transform::from_xyz(3., 2., 4.).looking_at(Vec3::ZERO, Vec3::Y),
         ..default()
     });