Fix bunnymark test screenshot and replace rand with nanorand (#2746)

Co-authored-by: Connor Fitzgerald <connorwadefitzgerald@gmail.com>

wgpu/Cargo.toml

@@ -130,7 +130,7 @@ log = "0.4"
 noise = { version = "0.7", default-features = false }
 obj = "0.10"
 png = "0.17"
-rand = "0.7.2"
+nanorand = { version = "0.7", default-features = false, features = ["wyrand"] }
 winit = "0.26"
 
 [target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
@@ -295,4 +295,3 @@ console_error_panic_hook = "0.1.6"
 console_log = "0.1.2"
 # We need the Location feature in the framework examples
 web-sys = { version = "0.3.53", features = ["Location"] }
-rand = { version = "0.7", features = ["wasm-bindgen"] }

wgpu/examples/boids/main.rs

@@ -1,10 +1,7 @@
 // Flocking boids example with gpu compute update pass
 // adapted from https://github.com/austinEng/webgpu-samples/blob/master/src/examples/computeBoids.ts
 
-use rand::{
-    distributions::{Distribution, Uniform},
-    SeedableRng,
-};
+use nanorand::{Rng, WyRand};
 use std::{borrow::Cow, mem};
 use wgpu::util::DeviceExt;
 
@@ -183,13 +180,13 @@ impl framework::Example for Example {
         // buffer for all particles data of type [(posx,posy,velx,vely),...]
 
         let mut initial_particle_data = vec![0.0f32; (4 * NUM_PARTICLES) as usize];
-        let mut rng = rand::rngs::StdRng::seed_from_u64(42);
-        let unif = Uniform::new_inclusive(-1.0, 1.0);
+        let mut rng = WyRand::new_seed(42);
+        let mut unif = || rng.generate::<f32>() * 2f32 - 1f32; // Generate a num (-1, 1)
         for particle_instance_chunk in initial_particle_data.chunks_mut(4) {
-            particle_instance_chunk[0] = unif.sample(&mut rng); // posx
-            particle_instance_chunk[1] = unif.sample(&mut rng); // posy
-            particle_instance_chunk[2] = unif.sample(&mut rng) * 0.1; // velx
-            particle_instance_chunk[3] = unif.sample(&mut rng) * 0.1; // vely
+            particle_instance_chunk[0] = unif(); // posx
+            particle_instance_chunk[1] = unif(); // posy
+            particle_instance_chunk[2] = unif() * 0.1; // velx
+            particle_instance_chunk[3] = unif() * 0.1; // vely
         }
 
         // creates two buffers of particle data each of size NUM_PARTICLES

wgpu/examples/bunnymark/main.rs

@@ -1,4 +1,5 @@
 use bytemuck::{Pod, Zeroable};
+use nanorand::{Rng, WyRand};
 use std::{borrow::Cow, mem};
 use wgpu::util::DeviceExt;
 
@@ -35,6 +36,7 @@ struct Example {
     bunnies: Vec<Locals>,
     local_buffer: wgpu::Buffer,
     extent: [u32; 2],
+    rng: WyRand,
 }
 
 impl framework::Example for Example {
@@ -234,13 +236,16 @@ impl framework::Example for Example {
             label: None,
         });
 
+        let rng = WyRand::new_seed(42);
+
         Example {
             pipeline,
             global_group,
             local_group,
             bunnies: Vec::new(),
             local_buffer,
             extent: [config.width, config.height],
+            rng,
         }
     }
 
@@ -256,14 +261,14 @@ impl framework::Example for Example {
         } = event
         {
             let spawn_count = 64 + self.bunnies.len() / 2;
-            let color = rand::random::<u32>();
+            let color = self.rng.generate::<u32>();
             println!(
                 "Spawning {} bunnies, total at {}",
                 spawn_count,
                 self.bunnies.len() + spawn_count
             );
             for _ in 0..spawn_count {
-                let speed = rand::random::<f32>() * MAX_VELOCITY - (MAX_VELOCITY * 0.5);
+                let speed = self.rng.generate::<f32>() * MAX_VELOCITY - (MAX_VELOCITY * 0.5);
                 self.bunnies.push(Locals {
                     position: [0.0, 0.5 * (self.extent[1] as f32)],
                     velocity: [speed, 0.0],
@@ -360,7 +365,7 @@ fn bunnymark() {
         height: 768,
         optional_features: wgpu::Features::default(),
         base_test_parameters: framework::test_common::TestParameters::default(),
-        tolerance: 1,
-        max_outliers: 50,
+        tolerance: 10,
+        max_outliers: 53, // Bounded by WARP
     });
 }

wgpu/examples/framework.rs

@@ -574,6 +574,27 @@ pub fn test<E: Example>(mut params: FrameworkRefTest) {
 
             example.render(&dst_view, &ctx.device, &ctx.queue, &spawner);
 
+            // Handle specific case for bunnymark
+            #[allow(deprecated)]
+            if params.image_path == "/examples/bunnymark/screenshot.png" {
+                // Press spacebar to spawn bunnies
+                example.update(winit::event::WindowEvent::KeyboardInput {
+                    input: winit::event::KeyboardInput {
+                        scancode: 0,
+                        state: winit::event::ElementState::Pressed,
+                        virtual_keycode: Some(winit::event::VirtualKeyCode::Space),
+                        modifiers: winit::event::ModifiersState::empty(),
+                    },
+                    device_id: unsafe { winit::event::DeviceId::dummy() },
+                    is_synthetic: false,
+                });
+
+                // Step 3 extra frames
+                for _ in 0..3 {
+                    example.render(&dst_view, &ctx.device, &ctx.queue, &spawner);
+                }
+            }
+
             let mut cmd_buf = ctx
                 .device
                 .create_command_encoder(&wgpu::CommandEncoderDescriptor::default());

wgpu/examples/water/main.rs

@@ -5,7 +5,7 @@ mod point_gen;
 
 use bytemuck::{Pod, Zeroable};
 use glam::Vec3;
-use rand::SeedableRng;
+use nanorand::{Rng, WyRand};
 use std::{borrow::Cow, f32::consts, iter, mem};
 use wgpu::util::DeviceExt;
 
@@ -285,13 +285,12 @@ impl framework::Example for Example {
         let terrain_noise = noise::OpenSimplex::new();
 
         // Random colouration
-        let mut terrain_random = rand::rngs::StdRng::seed_from_u64(42);
+        let mut terrain_random = WyRand::new_seed(42);
 
         // Generate terrain. The closure determines what each hexagon will look like.
         let terrain =
             point_gen::HexTerrainMesh::generate(SIZE, |point| -> point_gen::TerrainVertex {
                 use noise::NoiseFn;
-                use rand::Rng;
                 let noise = terrain_noise.get([point[0] as f64 / 5.0, point[1] as f64 / 5.0]) + 0.1;
 
                 let y = noise as f32 * 22.0;
@@ -314,7 +313,7 @@ impl framework::Example for Example {
                 const SNOW: [u8; 4] = [175, 224, 237, 255];
 
                 // Random colouration.
-                let random = terrain_random.gen::<f32>() * 0.2 + 0.9;
+                let random = terrain_random.generate::<f32>() * 0.2 + 0.9;
 
                 // Choose colour.
                 let colour = if y <= 0.0 {

wgpu/tests/common/image.rs

@@ -107,7 +107,7 @@ pub fn compare_image_output(
             .unwrap();
 
         if outliers > max_outliers {
-            // Because the deta is mismatched, lets output the difference to a file.
+            // Because the data is mismatched, lets output the difference to a file.
             let old_path = Path::new(&path);
             let actual_path = Path::new(&path).with_file_name(
                 OsString::from_str(