add bevymark benchmark example (#273)

add bevymark example

Cargo.toml

@@ -266,6 +266,10 @@ path = "examples/shader/shader_custom_material.rs"
 name = "shader_defs"
 path = "examples/shader/shader_defs.rs"
 
+[[example]]
+name = "bevymark"
+path = "examples/tools/bevymark.rs"
+
 [[example]]
 name = "button"
 path = "examples/ui/button.rs"

examples/tools/bevymark.rs

@@ -0,0 +1,160 @@
+use bevy::{
+    diagnostic::{Diagnostics, FrameTimeDiagnosticsPlugin},
+    prelude::*,
+};
+
+const BIRDS_PER_SECOND: u32 = 1000;
+const GRAVITY: f32 = -9.8 * 100.0;
+const MAX_VELOCITY: f32 = 750.;
+const BIRD_SCALE: f32 = 0.15;
+const HALF_BIRD_SIZE: f32 = 256. * BIRD_SCALE * 0.5;
+struct BevyCounter {
+    pub count: u128,
+}
+
+struct Bird {
+    velocity: Vec3,
+}
+
+struct BirdMaterial(Handle<ColorMaterial>);
+
+impl FromResources for BirdMaterial {
+    fn from_resources(resources: &Resources) -> Self {
+        let mut color_materials = resources.get_mut::<Assets<ColorMaterial>>().unwrap();
+        let asset_server = resources.get_mut::<AssetServer>().unwrap();
+        BirdMaterial(color_materials.add(asset_server.load("branding/icon.png").into()))
+    }
+}
+
+fn main() {
+    App::build()
+        .add_resource(WindowDescriptor {
+            title: "BevyMark".to_string(),
+            width: 800,
+            height: 600,
+            vsync: true,
+            resizable: false,
+            ..Default::default()
+        })
+        .add_plugins(DefaultPlugins)
+        .add_plugin(FrameTimeDiagnosticsPlugin::default())
+        .add_resource(BevyCounter { count: 0 })
+        .init_resource::<BirdMaterial>()
+        .add_startup_system(setup.system())
+        .add_system(mouse_handler.system())
+        .add_system(movement_system.system())
+        .add_system(collision_system.system())
+        .add_system(counter_system.system())
+        .run();
+}
+
+fn setup(commands: &mut Commands, asset_server: Res<AssetServer>) {
+    commands
+        .spawn(Camera2dComponents::default())
+        .spawn(UiCameraComponents::default())
+        .spawn(TextComponents {
+            text: Text {
+                font: asset_server.load("fonts/FiraSans-Bold.ttf"),
+                value: "Bird Count:".to_string(),
+                style: TextStyle {
+                    color: Color::rgb(0.0, 1.0, 0.0),
+                    font_size: 40.0,
+                    ..Default::default()
+                },
+            },
+            style: Style {
+                position_type: PositionType::Absolute,
+                position: Rect {
+                    top: Val::Px(5.0),
+                    left: Val::Px(5.0),
+                    ..Default::default()
+                },
+                ..Default::default()
+            },
+            ..Default::default()
+        });
+}
+
+fn mouse_handler(
+    commands: &mut Commands,
+    time: Res<Time>,
+    mouse_button_input: Res<Input<MouseButton>>,
+    window: Res<WindowDescriptor>,
+    bird_material: Res<BirdMaterial>,
+    mut counter: ResMut<BevyCounter>,
+) {
+    if mouse_button_input.pressed(MouseButton::Left) {
+        let spawn_count = (BIRDS_PER_SECOND as f32 * time.delta_seconds) as u128;
+        let bird_x = (window.width as i32 / -2) as f32 + HALF_BIRD_SIZE;
+        let bird_y = (window.height / 2) as f32 - HALF_BIRD_SIZE;
+
+        for count in 0..spawn_count {
+            let bird_position = Vec3::new(bird_x, bird_y, (counter.count + count) as f32 * 0.00001);
+            let mut transform = Transform::from_translation(bird_position);
+            transform.scale = Vec3::new(BIRD_SCALE, BIRD_SCALE, BIRD_SCALE);
+
+            commands
+                .spawn(SpriteComponents {
+                    material: bird_material.0.clone(),
+                    transform,
+                    draw: Draw {
+                        is_transparent: true,
+                        ..Default::default()
+                    },
+                    ..Default::default()
+                })
+                .with(Bird {
+                    velocity: Vec3::new(
+                        rand::random::<f32>() * MAX_VELOCITY - (MAX_VELOCITY * 0.5),
+                        0.,
+                        0.,
+                    ),
+                });
+        }
+
+        counter.count += spawn_count;
+    }
+}
+
+fn movement_system(time: Res<Time>, mut bird_query: Query<(&mut Bird, &mut Transform)>) {
+    for (mut bird, mut transform) in bird_query.iter_mut() {
+        *transform.translation.x_mut() += bird.velocity.x() * time.delta_seconds;
+        *transform.translation.y_mut() += bird.velocity.y() * time.delta_seconds;
+        *bird.velocity.y_mut() += GRAVITY * time.delta_seconds;
+    }
+}
+
+fn collision_system(window: Res<WindowDescriptor>, mut bird_query: Query<(&mut Bird, &Transform)>) {
+    let half_width = window.width as f32 * 0.5;
+    let half_height = window.height as f32 * 0.5;
+
+    for (mut bird, transform) in bird_query.iter_mut() {
+        let x_vel = bird.velocity.x();
+        let y_vel = bird.velocity.y();
+        let x_pos = transform.translation.x();
+        let y_pos = transform.translation.y();
+
+        if (x_vel > 0. && x_pos + HALF_BIRD_SIZE > half_width)
+            || (x_vel <= 0. && x_pos - HALF_BIRD_SIZE < -(half_width))
+        {
+            bird.velocity.set_x(-x_vel);
+        }
+        if y_vel < 0. && y_pos - HALF_BIRD_SIZE < -half_height {
+            bird.velocity.set_y(-y_vel);
+        }
+    }
+}
+
+fn counter_system(
+    diagnostics: Res<Diagnostics>,
+    counter: Res<BevyCounter>,
+    mut query: Query<&mut Text>,
+) {
+    if let Some(fps) = diagnostics.get(FrameTimeDiagnosticsPlugin::FPS) {
+        if let Some(average) = fps.average() {
+            for mut text in query.iter_mut() {
+                text.value = format!("Bird Count: {}\nAverage FPS: {:.2}", counter.count, average);
+            }
+        }
+    };
+}