Stablized bvh representation

studio/src/bvh/mod.rs

@@ -1,4 +1,5 @@
-use bevy::prelude::*;
+use bevy::{prelude::*, ecs::system::{Command, EntityCommands}, asset::AsyncReadExt};
+use studio_bvh::joint;
 
 mod error;
 mod loader;
@@ -10,21 +11,123 @@ pub struct BvhPlugin;
 impl Plugin for BvhPlugin {
     fn build(&self, app: &mut App) {
         app.init_asset::<Bvh>()
-            .init_asset::<BvhJoint>()
             .register_asset_loader(BvhLoader);
     }
 }
 
-#[derive(Asset, TypePath, Debug)]
-pub struct Bvh {
-    pub joints: Vec<BvhJoint>,
+//==============================================================================
+//                        Bvh Asset
+//==============================================================================
+
+#[derive(Clone, Debug, Default, Asset, TypePath)]
+pub struct Bvh(studio_bvh::Bvh);
+
+//==============================================================================
+//                        Bvh Anim Component
+//==============================================================================
+
+#[derive(Component, Debug)]
+pub struct BvhAnim {
+    pub bvh : Handle<Bvh>,
+    pub frame : usize,
 }
 
-#[derive(Asset, TypePath, Debug, Clone)]
-pub struct BvhJoint {
-    pub name: String,
-    /// Local transform
-    pub transform: Transform,
-    /// Direct children of this joint
-    pub children: Vec<BvhJoint>,
+//==============================================================================
+//                        Bvh Anim Component
+//==============================================================================
+
+#[derive(Debug, Component)]
+pub struct BvhJoint;
+
+//==============================================================================
+//                        Commands Plugin
+//==============================================================================
+
+pub trait CommandsSpawnBvhExt {
+    fn spawn_bvh(&mut self, asset : &Handle<Bvh>) -> Entity;
+
+    fn spawn_bvh_with_transform(&mut self, asset : &Handle<Bvh>, transform : Transform) -> Entity;
 }
+
+impl <'w, 's> CommandsSpawnBvhExt for Commands<'w, 's> {
+    fn spawn_bvh(&mut self, asset : &Handle<Bvh>) -> Entity {
+        let entity = self.spawn_empty().id();
+        self.add(SpawnBvhCommand(entity, 1.0, asset.clone()));
+        
+        self.entity(entity).insert(BvhAnim {
+            bvh : asset.clone(),
+            frame : 0,
+        });
+        entity
+    }
+
+    fn spawn_bvh_with_transform(&mut self, asset : &Handle<Bvh>, transform : Transform) -> Entity {
+        let entity = self.spawn_empty().id();
+        self.add(SpawnBvhCommand(entity, 1.0, asset.clone()));
+        
+        self.entity(entity).insert((
+            BvhAnim {
+                bvh : asset.clone(),
+                frame : 0,
+            },
+            transform
+        ));
+        entity
+    }
+}
+
+pub struct SpawnBvhCommand(Entity, f32, Handle<Bvh>);
+
+impl Command for SpawnBvhCommand {
+    fn apply(self, world: &mut World) {
+        let bvh = {
+            let Some(bvh) = world.get_resource::<Assets<Bvh>>().unwrap().get(self.2)
+            else { panic!("Could not create the BVH entity because the bvh file has not been loaded yet") };
+
+            bvh.clone()
+        };
+
+        let Some(root) = bvh.0.root_joint()
+        else { panic!("Could not create the BVH entity because the bvh file has no root joint") };
+
+        spawn_bvh_recursive(world, &self.0, root);
+    }
+} 
+
+//==============================================================================
+//                        Utility Functions
+//==============================================================================
+
+// fn spawn_bvh(commands : &mut Commands, asset : Handle<Bvh>, assets : &Res<Assets<Bvh>>) -> Option<Entity> {
+//     let Some(root) = bvh.0.root_joint()
+//     else { return None; };
+
+//     let tree = spawn_bvh_recursive(commands, &bvh.0, root);
+
+//     // commands.entity(tree).insert(BvhAnim {
+//     //     bvh : bvh.id(),
+//     //     frame : 0,
+//     // }
+
+//     // Some()
+// }
+
+fn spawn_bvh_recursive(world : &mut World, entity : &Entity, joint : studio_bvh::Joint) {
+    let offset = joint.data().offset();
+    let transform = Transform::from_xyz(offset[0], offset[1], offset[2]);
+
+    // Save the name of the joint
+    let name = String::from_utf8_lossy(joint.data().name()).to_string();
+
+    world.entity_mut(*entity).insert((
+        SpatialBundle::from_transform(transform), 
+        BvhJoint, 
+        Name::new(name)
+    ));
+
+    for child in joint.children() {
+        let mut child_entity = world.spawn_empty().id();
+        spawn_bvh_recursive(world, &child_entity, child);
+        world.entity_mut(*entity).push_children(&[child_entity]);
+    };
+}