bevy/examples/tools/scene_viewer/main.rs
Taras Palczynski III c7791ad9b3 Organized scene_viewer into plugins for reuse and organization (#6936)
# Objective

This PR reorganizes majority of the scene viewer example into a module of plugins which then allows reuse of functionality among new or existing examples.  In addition, this enables the scene viewer to be more succinct and showcase the distinct cases of camera control and scene control.

This work is to support future work in organization and future examples.  A more complicated 3D scene example has been requested by the community (#6551) which requests functionality currently included in scene_viewer, but previously inaccessible.  The future example can now just utilize the two plugins created here.  The existing example [animated_fox example] can utilize the scene creation and animation control functionality of `SceneViewerPlugin`.

## Solution

- Created a `scene_viewer` module inside the `tools` example folder.
- Created two plugins:  `SceneViewerPlugin` (gltf scene loading, animation control, camera tracking control, light control) and `CameraControllerPlugin` (controllable camera).
- Original `scene_viewer.rs` moved to `scene_viewer/main.rs` and now utilizes the two plugins.
2022-12-25 00:23:13 +00:00

164 lines
5.6 KiB
Rust

//! A simple glTF scene viewer made with Bevy.
//!
//! Just run `cargo run --release --example scene_viewer /path/to/model.gltf`,
//! replacing the path as appropriate.
//! In case of multiple scenes, you can select which to display by adapting the file path: `/path/to/model.gltf#Scene1`.
//! With no arguments it will load the `FlightHelmet` glTF model from the repository assets subdirectory.
use bevy::{
math::Vec3A,
prelude::*,
render::primitives::{Aabb, Sphere},
};
mod camera_controller_plugin;
mod scene_viewer_plugin;
use camera_controller_plugin::{CameraController, CameraControllerPlugin};
use scene_viewer_plugin::{SceneHandle, SceneViewerPlugin};
fn main() {
let mut app = App::new();
app.insert_resource(AmbientLight {
color: Color::WHITE,
brightness: 1.0 / 5.0f32,
})
.add_plugins(
DefaultPlugins
.set(WindowPlugin {
window: WindowDescriptor {
title: "bevy scene viewer".to_string(),
..default()
},
..default()
})
.set(AssetPlugin {
asset_folder: std::env::var("CARGO_MANIFEST_DIR")
.unwrap_or_else(|_| ".".to_string()),
watch_for_changes: true,
}),
)
.add_plugin(CameraControllerPlugin)
.add_plugin(SceneViewerPlugin)
.add_startup_system(setup)
.add_system_to_stage(CoreStage::PreUpdate, setup_scene_after_load);
app.run();
}
fn parse_scene(scene_path: String) -> (String, usize) {
if scene_path.contains('#') {
let gltf_and_scene = scene_path.split('#').collect::<Vec<_>>();
if let Some((last, path)) = gltf_and_scene.split_last() {
if let Some(index) = last
.strip_prefix("Scene")
.and_then(|index| index.parse::<usize>().ok())
{
return (path.join("#"), index);
}
}
}
(scene_path, 0)
}
fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
let scene_path = std::env::args()
.nth(1)
.unwrap_or_else(|| "assets/models/FlightHelmet/FlightHelmet.gltf".to_string());
info!("Loading {}", scene_path);
let (file_path, scene_index) = parse_scene(scene_path);
commands.insert_resource(SceneHandle::new(asset_server.load(file_path), scene_index));
}
fn setup_scene_after_load(
mut commands: Commands,
mut setup: Local<bool>,
mut scene_handle: ResMut<SceneHandle>,
meshes: Query<(&GlobalTransform, Option<&Aabb>), With<Handle<Mesh>>>,
) {
if scene_handle.is_loaded && !*setup {
*setup = true;
// Find an approximate bounding box of the scene from its meshes
if meshes.iter().any(|(_, maybe_aabb)| maybe_aabb.is_none()) {
return;
}
let mut min = Vec3A::splat(f32::MAX);
let mut max = Vec3A::splat(f32::MIN);
for (transform, maybe_aabb) in &meshes {
let aabb = maybe_aabb.unwrap();
// If the Aabb had not been rotated, applying the non-uniform scale would produce the
// correct bounds. However, it could very well be rotated and so we first convert to
// a Sphere, and then back to an Aabb to find the conservative min and max points.
let sphere = Sphere {
center: Vec3A::from(transform.transform_point(Vec3::from(aabb.center))),
radius: transform.radius_vec3a(aabb.half_extents),
};
let aabb = Aabb::from(sphere);
min = min.min(aabb.min());
max = max.max(aabb.max());
}
let size = (max - min).length();
let aabb = Aabb::from_min_max(Vec3::from(min), Vec3::from(max));
info!("Spawning a controllable 3D perspective camera");
let mut projection = PerspectiveProjection::default();
projection.far = projection.far.max(size * 10.0);
let camera_controller = CameraController::default();
// Display the controls of the scene viewer
info!("{}", camera_controller);
info!("{}", *scene_handle);
commands.spawn((
Camera3dBundle {
projection: projection.into(),
transform: Transform::from_translation(
Vec3::from(aabb.center) + size * Vec3::new(0.5, 0.25, 0.5),
)
.looking_at(Vec3::from(aabb.center), Vec3::Y),
camera: Camera {
is_active: false,
..default()
},
..default()
},
camera_controller,
));
// Spawn a default light if the scene does not have one
if !scene_handle.has_light {
let sphere = Sphere {
center: aabb.center,
radius: aabb.half_extents.length(),
};
let aabb = Aabb::from(sphere);
let min = aabb.min();
let max = aabb.max();
info!("Spawning a directional light");
commands.spawn(DirectionalLightBundle {
directional_light: DirectionalLight {
shadow_projection: OrthographicProjection {
left: min.x,
right: max.x,
bottom: min.y,
top: max.y,
near: min.z,
far: max.z,
..default()
},
shadows_enabled: false,
..default()
},
..default()
});
scene_handle.has_light = true;
}
}
}