forked from bevyengine/bevy
-
Notifications
You must be signed in to change notification settings - Fork 0
/
many_cubes.rs
317 lines (285 loc) · 10.5 KB
/
many_cubes.rs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
//! Simple benchmark to test per-entity draw overhead.
//!
//! To measure performance realistically, be sure to run this in release mode.
//! `cargo run --example many_cubes --release`
//!
//! By default, this arranges the meshes in a spherical pattern that
//! distributes the meshes evenly.
//!
//! See `cargo run --example many_cubes --release -- --help` for more options.
use std::{f64::consts::PI, str::FromStr};
use argh::FromArgs;
use bevy::{
diagnostic::{FrameTimeDiagnosticsPlugin, LogDiagnosticsPlugin},
math::{DVec2, DVec3},
prelude::*,
render::{
render_asset::RenderAssetUsages,
render_resource::{Extent3d, TextureDimension, TextureFormat},
},
window::{PresentMode, WindowPlugin, WindowResolution},
winit::{UpdateMode, WinitSettings},
};
use rand::{rngs::StdRng, seq::SliceRandom, Rng, SeedableRng};
#[derive(FromArgs, Resource)]
/// `many_cubes` stress test
struct Args {
/// how the cube instances should be positioned.
#[argh(option, default = "Layout::Sphere")]
layout: Layout,
/// whether to step the camera animation by a fixed amount such that each frame is the same across runs.
#[argh(switch)]
benchmark: bool,
/// whether to vary the material data in each instance.
#[argh(switch)]
vary_per_instance: bool,
/// the number of different textures from which to randomly select the material base color. 0 means no textures.
#[argh(option, default = "0")]
material_texture_count: usize,
}
#[derive(Default, Clone)]
enum Layout {
Cube,
#[default]
Sphere,
}
impl FromStr for Layout {
type Err = String;
fn from_str(s: &str) -> Result<Self, Self::Err> {
match s {
"cube" => Ok(Self::Cube),
"sphere" => Ok(Self::Sphere),
_ => Err(format!(
"Unknown layout value: '{}', valid options: 'cube', 'sphere'",
s
)),
}
}
}
fn main() {
// `from_env` panics on the web
#[cfg(not(target_arch = "wasm32"))]
let args: Args = argh::from_env();
#[cfg(target_arch = "wasm32")]
let args = Args::from_args(&[], &[]).unwrap();
App::new()
.add_plugins((
DefaultPlugins.set(WindowPlugin {
primary_window: Some(Window {
present_mode: PresentMode::AutoNoVsync,
resolution: WindowResolution::new(1920.0, 1080.0)
.with_scale_factor_override(1.0),
..default()
}),
..default()
}),
FrameTimeDiagnosticsPlugin,
LogDiagnosticsPlugin::default(),
))
.insert_resource(WinitSettings {
focused_mode: UpdateMode::Continuous,
unfocused_mode: UpdateMode::Continuous,
})
.insert_resource(args)
.add_systems(Startup, setup)
.add_systems(Update, (move_camera, print_mesh_count))
.run();
}
const WIDTH: usize = 200;
const HEIGHT: usize = 200;
fn setup(
mut commands: Commands,
args: Res<Args>,
mut meshes: ResMut<Assets<Mesh>>,
material_assets: ResMut<Assets<StandardMaterial>>,
images: ResMut<Assets<Image>>,
) {
warn!(include_str!("warning_string.txt"));
let args = args.into_inner();
let images = images.into_inner();
let material_assets = material_assets.into_inner();
let mesh = meshes.add(Cuboid::default());
let material_textures = init_textures(args, images);
let materials = init_materials(args, &material_textures, material_assets);
let mut material_rng = StdRng::seed_from_u64(42);
match args.layout {
Layout::Sphere => {
// NOTE: This pattern is good for testing performance of culling as it provides roughly
// the same number of visible meshes regardless of the viewing angle.
const N_POINTS: usize = WIDTH * HEIGHT * 4;
// NOTE: f64 is used to avoid precision issues that produce visual artifacts in the distribution
let radius = WIDTH as f64 * 2.5;
let golden_ratio = 0.5f64 * (1.0f64 + 5.0f64.sqrt());
for i in 0..N_POINTS {
let spherical_polar_theta_phi =
fibonacci_spiral_on_sphere(golden_ratio, i, N_POINTS);
let unit_sphere_p = spherical_polar_to_cartesian(spherical_polar_theta_phi);
commands.spawn(PbrBundle {
mesh: mesh.clone(),
material: materials.choose(&mut material_rng).unwrap().clone(),
transform: Transform::from_translation((radius * unit_sphere_p).as_vec3()),
..default()
});
}
// camera
commands.spawn(Camera3dBundle::default());
}
_ => {
// NOTE: This pattern is good for demonstrating that frustum culling is working correctly
// as the number of visible meshes rises and falls depending on the viewing angle.
for x in 0..WIDTH {
for y in 0..HEIGHT {
// introduce spaces to break any kind of moiré pattern
if x % 10 == 0 || y % 10 == 0 {
continue;
}
// cube
commands.spawn(PbrBundle {
mesh: mesh.clone(),
material: materials.choose(&mut material_rng).unwrap().clone(),
transform: Transform::from_xyz((x as f32) * 2.5, (y as f32) * 2.5, 0.0),
..default()
});
commands.spawn(PbrBundle {
mesh: mesh.clone(),
material: materials.choose(&mut material_rng).unwrap().clone(),
transform: Transform::from_xyz(
(x as f32) * 2.5,
HEIGHT as f32 * 2.5,
(y as f32) * 2.5,
),
..default()
});
commands.spawn(PbrBundle {
mesh: mesh.clone(),
material: materials.choose(&mut material_rng).unwrap().clone(),
transform: Transform::from_xyz((x as f32) * 2.5, 0.0, (y as f32) * 2.5),
..default()
});
commands.spawn(PbrBundle {
mesh: mesh.clone(),
material: materials.choose(&mut material_rng).unwrap().clone(),
transform: Transform::from_xyz(0.0, (x as f32) * 2.5, (y as f32) * 2.5),
..default()
});
}
}
// camera
commands.spawn(Camera3dBundle {
transform: Transform::from_xyz(WIDTH as f32, HEIGHT as f32, WIDTH as f32),
..default()
});
}
}
commands.spawn(DirectionalLightBundle::default());
}
fn init_textures(args: &Args, images: &mut Assets<Image>) -> Vec<Handle<Image>> {
let mut color_rng = StdRng::seed_from_u64(42);
let color_bytes: Vec<u8> = (0..(args.material_texture_count * 4))
.map(|i| if (i % 4) == 3 { 255 } else { color_rng.gen() })
.collect();
color_bytes
.chunks(4)
.map(|pixel| {
images.add(Image::new_fill(
Extent3d {
width: 1,
height: 1,
depth_or_array_layers: 1,
},
TextureDimension::D2,
pixel,
TextureFormat::Rgba8UnormSrgb,
RenderAssetUsages::RENDER_WORLD,
))
})
.collect()
}
fn init_materials(
args: &Args,
textures: &[Handle<Image>],
assets: &mut Assets<StandardMaterial>,
) -> Vec<Handle<StandardMaterial>> {
let capacity = if args.vary_per_instance {
match args.layout {
Layout::Cube => (WIDTH - WIDTH / 10) * (HEIGHT - HEIGHT / 10),
Layout::Sphere => WIDTH * HEIGHT * 4,
}
} else {
args.material_texture_count
}
.max(1);
let mut materials = Vec::with_capacity(capacity);
materials.push(assets.add(StandardMaterial {
base_color: Color::WHITE,
base_color_texture: textures.first().cloned(),
..default()
}));
let mut color_rng = StdRng::seed_from_u64(42);
let mut texture_rng = StdRng::seed_from_u64(42);
materials.extend(
std::iter::repeat_with(|| {
assets.add(StandardMaterial {
base_color: Color::rgb_u8(color_rng.gen(), color_rng.gen(), color_rng.gen()),
base_color_texture: textures.choose(&mut texture_rng).cloned(),
..default()
})
})
.take(capacity - materials.len()),
);
materials
}
// NOTE: This epsilon value is apparently optimal for optimizing for the average
// nearest-neighbor distance. See:
// http://extremelearning.com.au/how-to-evenly-distribute-points-on-a-sphere-more-effectively-than-the-canonical-fibonacci-lattice/
// for details.
const EPSILON: f64 = 0.36;
fn fibonacci_spiral_on_sphere(golden_ratio: f64, i: usize, n: usize) -> DVec2 {
DVec2::new(
PI * 2. * (i as f64 / golden_ratio),
(1.0 - 2.0 * (i as f64 + EPSILON) / (n as f64 - 1.0 + 2.0 * EPSILON)).acos(),
)
}
fn spherical_polar_to_cartesian(p: DVec2) -> DVec3 {
let (sin_theta, cos_theta) = p.x.sin_cos();
let (sin_phi, cos_phi) = p.y.sin_cos();
DVec3::new(cos_theta * sin_phi, sin_theta * sin_phi, cos_phi)
}
// System for rotating the camera
fn move_camera(
time: Res<Time>,
args: Res<Args>,
mut camera_query: Query<&mut Transform, With<Camera>>,
) {
let mut camera_transform = camera_query.single_mut();
let delta = 0.15
* if args.benchmark {
1.0 / 60.0
} else {
time.delta_seconds()
};
camera_transform.rotate_z(delta);
camera_transform.rotate_x(delta);
}
// System for printing the number of meshes on every tick of the timer
fn print_mesh_count(
time: Res<Time>,
mut timer: Local<PrintingTimer>,
sprites: Query<(&Handle<Mesh>, &ViewVisibility)>,
) {
timer.tick(time.delta());
if timer.just_finished() {
info!(
"Meshes: {} - Visible Meshes {}",
sprites.iter().len(),
sprites.iter().filter(|(_, vis)| vis.get()).count(),
);
}
}
#[derive(Deref, DerefMut)]
struct PrintingTimer(Timer);
impl Default for PrintingTimer {
fn default() -> Self {
Self(Timer::from_seconds(1.0, TimerMode::Repeating))
}
}