.vscode/launch.json

@@ -83,6 +83,28 @@
             },
             "args": [],
             "cwd": "${workspaceFolder}/lyra-ecs"
+        },
+        {
+            "type": "lldb",
+            "request": "launch",
+            "name": "Debug unit tests in executable 'lyra-scene'",
+            "cargo": {
+                "args": [
+                    "test",
+                    "--no-run",
+                    "--lib",
+                    "--package=lyra-scene",
+                    //"command::tests::deferred_commands",
+                    //"--",
+                    //"--exact --nocapture"
+                ],
+                "filter": {
+                    "name": "lyra-scene",
+                    "kind": "lib"
+                }
+            },
+            "args": [],
+            "cwd": "${workspaceFolder}/lyra-scene"
         }
     ]
 }

Cargo.lock

@@ -1845,7 +1845,9 @@ dependencies = [
  "gltf",
  "image",
  "infer",
+ "instant",
  "lyra-ecs",
+ "lyra-math",
  "mime",
  "notify",
  "notify-debouncer-full",
@@ -1855,6 +1857,14 @@ dependencies = [
  "uuid",
 ]
 
+[[package]]
+name = "lyra-scene"
+version = "0.1.0"
+dependencies = [
+ "lyra-ecs",
+ "lyra-math",
+]
+
 [[package]]
 name = "lyra-scripting"
 version = "0.1.0"
@@ -3093,7 +3103,6 @@ dependencies = [
  "async-std",
  "fps_counter",
  "lyra-engine",
- "lyra-scripting",
  "tracing",
 ]
 

Cargo.toml

@@ -10,7 +10,7 @@ members = [
     "lyra-ecs",
     "lyra-reflect",
     "lyra-scripting",
-    "lyra-game", "lyra-math"]
+    "lyra-game", "lyra-math", "lyra-scene"]
 
 [features]
 scripting = ["dep:lyra-scripting"]

examples/testbed/Cargo.toml

@@ -6,8 +6,9 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-lyra-engine = { path = "../../", version = "0.0.1", features = ["lua_scripting"] }
+lyra-engine = { path = "../../", version = "0.0.1" }
-lyra-scripting = { path = "../../lyra-scripting", features = ["lua", "teal"] }
+#lyra-engine = { path = "../../", version = "0.0.1", features = ["lua_scripting"] }
+#lyra-scripting = { path = "../../lyra-scripting", features = ["lua", "teal"] }
 #lyra-ecs = { path = "../../lyra-ecs"}
 anyhow = "1.0.75"
 async-std = "1.12.0"

examples/testbed/assets/sponza/.gitignore

@@ -0,0 +1,2 @@
+Sponza*
+Textures

examples/testbed/assets/sponza/README.md

@@ -0,0 +1 @@
+To keep the size of this repository down, the Sponza scene is omitted from this repo. The files were downloaded from https://github.com/toji/sponza-optimized

examples/testbed/src/main.rs

@@ -1,7 +1,7 @@
 use std::ptr::NonNull;
 
-use lyra_engine::{math::{self, Vec3}, math::Transform, input::{KeyCode, ActionHandler, Action, ActionKind, LayoutId, ActionMapping, ActionSource, ActionMappingId, InputActionPlugin, MouseInput, MouseAxis, CommonActionLabel}, game::Game, render::{window::{CursorGrabMode, WindowOptions}, light::{PointLight, directional::DirectionalLight, SpotLight}}, change_tracker::Ct, ecs::{system::{Criteria, CriteriaSchedule, BatchedSystem, IntoSystem}, World, Component}, DeltaTime, scene::{ModelComponent, CameraComponent}, lua::{LuaScriptingPlugin, LuaScript}, Script, ScriptList};
+use lyra_engine::{assets::gltf::Gltf, ecs::{system::{BatchedSystem, Criteria, CriteriaSchedule, IntoSystem}, Component, World}, game::Game, input::{Action, ActionHandler, ActionKind, ActionMapping, ActionMappingId, ActionSource, InputActionPlugin, KeyCode, LayoutId, MouseAxis, MouseInput}, math::{self, Transform, Vec3}, render::light::{directional::DirectionalLight, PointLight, SpotLight}, scene::{CameraComponent, MeshComponent}, DeltaTime};
-use lyra_engine::assets::{ResourceManager, Model};
+use lyra_engine::assets::ResourceManager;
 
 mod free_fly_camera;
 use free_fly_camera::{FreeFlyCameraPlugin, FreeFlyCamera};
@@ -16,6 +16,13 @@ pub enum ActionLabel {
     LookRoll,
 }
 
+const ACTLBL_MOVE_UP_DOWN: &str = "MoveUpDown";
+const ACTLBL_MOVE_LEFT_RIGHT: &str = "MoveLeftRight";
+const ACTLBL_MOVE_FORWARD_BACKWARD: &str = "MoveForwardBackward";
+const ACTLBL_LOOK_LEFT_RIGHT: &str = "LookLeftRight";
+const ACTLBL_LOOK_UP_DOWN: &str = "LookUpDown";
+const ACTLBL_LOOK_ROLL: &str = "LookRoll";
+
 struct FixedTimestep {
     max_tps: u32,
     fixed_time: f32,
@@ -86,30 +93,45 @@ async fn main() {
         //let diffuse_texture = resman.request::<Texture>("assets/happy-tree.png").unwrap();
         //let antique_camera_model = resman.request::<Model>("assets/AntiqueCamera.glb").unwrap();
         //let cube_model = resman.request::<Model>("assets/cube-texture-bin.glb").unwrap();
-        let cube_model = resman.request::<Model>("assets/texture-sep/texture-sep.gltf").unwrap();
+        /* let cube_gltf = resman.request::<Gltf>("assets/texture-sep/texture-sep.gltf").unwrap();
-        let crate_model = resman.request::<Model>("assets/crate/crate.gltf").unwrap();
+        let crate_gltf = resman.request::<Gltf>("assets/crate/crate.gltf").unwrap();
-        //let sponza_model = resman.request::<Model>("assets/sponza/Sponza.gltf").unwrap();
+
+        let separate_gltf = resman.request::<Gltf>("assets/pos-testing/child-node-cubes.glb").unwrap(); */
+        //drop(resman);
+        
+        /* let cube_mesh = &cube_gltf.data_ref()
+            .unwrap().meshes[0];
+        let crate_mesh = &crate_gltf.data_ref()
+            .unwrap().meshes[0];
+
+        let separate_scene = &separate_gltf.data_ref()
+            .unwrap().scenes[0]; */
+
+        let sponza_model = resman.request::<Gltf>("assets/sponza/Sponza.gltf").unwrap();
         drop(resman);
 
+        let sponza_scene = &sponza_model.data_ref()
+            .unwrap().scenes[0];
+
+        world.spawn((
+            sponza_scene.clone(),
+            Transform::from_xyz(0.0, 0.0, 0.0),
+        ));
+
         /* world.spawn((
-            ModelComponent(antique_camera_model),
+            separate_scene.clone(),
             Transform::from_xyz(0.0, -5.0, -10.0),
         )); */
 
-        /* world.spawn((
+        /* {
-            ModelComponent(sponza_model),
+            let cube_tran = Transform::from_xyz(-5.9026427, -1.8953488, -10.0);
-            Transform::from_xyz(0.0, 0.0, 0.0),
-        )); */
-
-        {
-            let cube_tran = Transform::from_xyz(-3.5, 0.0, -8.0);
             //cube_tran.rotate_y(math::Angle::Degrees(180.0));
             world.spawn((
                 cube_tran,
-                ModelComponent(crate_model.clone()),
+                crate_mesh.clone(),
                 CubeFlag,
             ));
-        }
+        } */
 
         {
             let mut light_tran = Transform::from_xyz(1.5, 2.5, 0.0);
@@ -124,11 +146,11 @@ async fn main() {
                     specular: 1.3,
                 },
                 light_tran,
-                ModelComponent(cube_model.clone()),
+                //cube_mesh.clone(),
             ));
         }
 
-        {
+        /* {
             let mut light_tran = Transform::from_xyz(-3.5, 0.2, -4.5);
             light_tran.scale = Vec3::new(0.5, 0.5, 0.5);
             world.spawn((
@@ -146,10 +168,32 @@ async fn main() {
                     specular: 1.0,
                 },
                 Transform::from(light_tran),
-                ModelComponent(cube_model.clone()),
+                cube_mesh.clone(),
             ));
         }
 
+        {
+            let mut light_tran = Transform::from_xyz(2.0, 2.5, -9.5);
+            light_tran.scale = Vec3::new(0.5, 0.5, 0.5);
+            world.spawn((
+                PointLight {
+                    color: Vec3::new(0.0, 0.0, 1.0),
+
+                    intensity: 3.3,
+
+                    constant: 1.0,
+                    linear: 0.09,
+                    quadratic: 0.032,
+                    
+                    ambient: 0.2,
+                    diffuse: 1.0,
+                    specular: 1.3,
+                },
+                Transform::from(light_tran),
+                cube_mesh.clone(),
+            ));
+        } */
+        
         /* {
             let mut light_tran = Transform::from_xyz(-5.0, 2.5, -9.5);
             light_tran.scale = Vec3::new(0.5, 0.5, 0.5);
@@ -172,28 +216,6 @@ async fn main() {
             ));
         } */
 
-        {
-            let mut light_tran = Transform::from_xyz(2.0, 2.5, -9.5);
-            light_tran.scale = Vec3::new(0.5, 0.5, 0.5);
-            world.spawn((
-                PointLight {
-                    color: Vec3::new(0.0, 0.0, 1.0),
-
-                    intensity: 3.3,
-
-                    constant: 1.0,
-                    linear: 0.09,
-                    quadratic: 0.032,
-                    
-                    ambient: 0.2,
-                    diffuse: 1.0,
-                    specular: 1.3,
-                },
-                Transform::from(light_tran),
-                ModelComponent(cube_model),
-            ));
-        }
-
         let mut camera = CameraComponent::new_3d();
         camera.transform.translation += math::Vec3::new(0.0, 0.0, 5.5);
         world.spawn(( camera, FreeFlyCamera::default() ));
@@ -211,7 +233,7 @@ async fn main() {
 
         Ok(())
     };
-    let fps_plugin = move |game: &mut Game| {
+    let _fps_plugin = move |game: &mut Game| {
         let world = game.world_mut();
         world.add_resource(fps_counter::FPSCounter::new());
     };
@@ -246,54 +268,54 @@ async fn main() {
     };
 
     let action_handler_plugin = |game: &mut Game| {
-        /* let action_handler = ActionHandler::builder()
+        let action_handler = ActionHandler::builder()
             .add_layout(LayoutId::from(0))
             
-            .add_action(CommonActionLabel::MoveForwardBackward, Action::new(ActionKind::Axis))
+            .add_action(ACTLBL_MOVE_FORWARD_BACKWARD, Action::new(ActionKind::Axis))
-            .add_action(CommonActionLabel::MoveLeftRight, Action::new(ActionKind::Axis))
+            .add_action(ACTLBL_MOVE_LEFT_RIGHT, Action::new(ActionKind::Axis))
-            .add_action(CommonActionLabel::MoveUpDown, Action::new(ActionKind::Axis))
+            .add_action(ACTLBL_MOVE_UP_DOWN, Action::new(ActionKind::Axis))
-            .add_action(CommonActionLabel::LookLeftRight, Action::new(ActionKind::Axis))
+            .add_action(ACTLBL_LOOK_LEFT_RIGHT, Action::new(ActionKind::Axis))
-            .add_action(CommonActionLabel::LookUpDown, Action::new(ActionKind::Axis))
+            .add_action(ACTLBL_LOOK_UP_DOWN, Action::new(ActionKind::Axis))
-            .add_action(CommonActionLabel::LookRoll, Action::new(ActionKind::Axis))
+            .add_action(ACTLBL_LOOK_ROLL, Action::new(ActionKind::Axis))
 
             .add_mapping(ActionMapping::builder(LayoutId::from(0), ActionMappingId::from(0))
-                .bind(CommonActionLabel::MoveForwardBackward, &[
+                .bind(ACTLBL_MOVE_FORWARD_BACKWARD, &[
                     ActionSource::Keyboard(KeyCode::W).into_binding_modifier(1.0),
                     ActionSource::Keyboard(KeyCode::S).into_binding_modifier(-1.0)
                 ])
-                .bind(CommonActionLabel::MoveLeftRight, &[
+                .bind(ACTLBL_MOVE_LEFT_RIGHT, &[
                     ActionSource::Keyboard(KeyCode::A).into_binding_modifier(-1.0),
                     ActionSource::Keyboard(KeyCode::D).into_binding_modifier(1.0)
                 ])
-                .bind(CommonActionLabel::MoveUpDown, &[
+                .bind(ACTLBL_MOVE_UP_DOWN, &[
                     ActionSource::Keyboard(KeyCode::C).into_binding_modifier(1.0),
                     ActionSource::Keyboard(KeyCode::Z).into_binding_modifier(-1.0)
                 ])
-                .bind(CommonActionLabel::LookLeftRight, &[
+                .bind(ACTLBL_LOOK_LEFT_RIGHT, &[
                     ActionSource::Mouse(MouseInput::Axis(MouseAxis::X)).into_binding(),
                     ActionSource::Keyboard(KeyCode::Left).into_binding_modifier(-1.0),
                     ActionSource::Keyboard(KeyCode::Right).into_binding_modifier(1.0),
                     //ActionSource::Gamepad(GamepadFormat::DualAxis, GamepadInput::Axis(GamepadAxis::RThumbstickX)).into_binding(),
                 ])
-                .bind(CommonActionLabel::LookUpDown, &[
+                .bind(ACTLBL_LOOK_UP_DOWN, &[
                     ActionSource::Mouse(MouseInput::Axis(MouseAxis::Y)).into_binding(),
                     ActionSource::Keyboard(KeyCode::Up).into_binding_modifier(-1.0),
                     ActionSource::Keyboard(KeyCode::Down).into_binding_modifier(1.0),
                     //ActionSource::Gamepad(GamepadFormat::DualAxis, GamepadInput::Axis(GamepadAxis::RThumbstickY)).into_binding(),
                 ])
-                .bind(CommonActionLabel::LookRoll, &[
+                .bind(ACTLBL_LOOK_ROLL, &[
                     ActionSource::Keyboard(KeyCode::E).into_binding_modifier(-1.0),
                     ActionSource::Keyboard(KeyCode::Q).into_binding_modifier(1.0),
                 ])
                 .finish()
-            );
+            ).finish();
 
         let world = game.world_mut();
-        world.add_resource(action_handler); */
+        world.add_resource(action_handler);
         game.with_plugin(InputActionPlugin);
     };
 
-    let script_test_plugin = |game: &mut Game| {
+    /* let script_test_plugin = |game: &mut Game| {
         game.with_plugin(LuaScriptingPlugin);
 
         let world = game.world_mut();
@@ -306,13 +328,13 @@ async fn main() {
         let scripts = ScriptList::new(vec![script]);
         world.spawn((scripts,));
 
-    };
+    }; */
     
     Game::initialize().await
         .with_plugin(lyra_engine::DefaultPlugins)
         .with_startup_system(setup_sys.into_system())
         .with_plugin(action_handler_plugin)
-        .with_plugin(script_test_plugin)
+        //.with_plugin(script_test_plugin)
         //.with_plugin(fps_plugin)
         .with_plugin(jiggle_plugin)
         .with_plugin(FreeFlyCameraPlugin)

lyra-ecs/src/archetype.rs

@@ -55,7 +55,6 @@ impl ComponentColumn {
     /// Set a component from pointer at an entity index.
     /// 
     /// # Safety
-    /// 
     /// This column must have space to fit the component, if it does not have room it will panic.
     pub unsafe fn set_at(&mut self, entity_index: usize, comp_src: NonNull<u8>, tick: Tick) {
         assert!(entity_index < self.capacity);
@@ -76,6 +75,23 @@ impl ComponentColumn {
         }
     }
 
+    /// Inserts an entity and its component at a specific index.
+    pub unsafe fn insert_entity(&mut self, entity_index: usize, comp_src: NonNull<u8>, tick: Tick) {
+        assert!(entity_index < self.capacity);
+
+        let mut data = self.data.borrow_mut();
+        let data = data.deref_mut();
+        
+        let size = self.info.layout().size();
+        let dest = NonNull::new_unchecked(data.as_ptr().add(entity_index * size));
+        ptr::copy_nonoverlapping(comp_src.as_ptr(), dest.as_ptr(), size);
+
+        // check if a component spot is being set twice and that the entity's tick is
+        // already stored
+        self.entity_ticks.push(tick);
+        self.len += 1;
+    }
+
     /// Get a component at an entities index.
     /// 
     /// # Safety
@@ -153,6 +169,8 @@ impl ComponentColumn {
     pub unsafe fn remove_component(&mut self, entity_index: usize, tick: &Tick) -> Option<usize> {
         let _ = tick; // may be used at some point
 
+        debug_assert!(self.len > 0, "There are no entities in the Archetype to remove from!");
+        
         let mut data = self.data.borrow_mut();
         let data = data.deref_mut();
 
@@ -170,8 +188,7 @@ impl ComponentColumn {
             mem::swap(&mut old_comp_ptr, &mut new_comp_ptr); // new_comp_ptr is now the old ptr
 
             // make sure to keep entity indexes correct in the ticks list as well
-            self.entity_ticks.swap(moved_index, entity_index);
+            self.entity_ticks.swap_remove(entity_index);
-            self.entity_ticks.pop();
 
             Some(moved_index)
         } else { None };
@@ -283,8 +300,7 @@ impl Archetype {
 
         bundle.take(|data, type_id, _size| {
             let col = self.get_column_mut(type_id).unwrap();
-            unsafe { col.set_at(entity_index.0 as usize, data, *tick); }
+            unsafe { col.insert_entity(entity_index.0 as usize, data, *tick); }
-            col.len += 1;
         });
         
         entity_index
@@ -293,21 +309,21 @@ impl Archetype {
     /// Removes an entity from the Archetype and frees its components. Returns the entity record
     /// that took its place in the component column.
     pub(crate) fn remove_entity(&mut self, entity: Entity, tick: &Tick) -> Option<(Entity, ArchetypeEntityId)> {
-        let entity_index = *self.entity_ids.get(&entity)
+        let entity_index = self.entity_ids.remove(&entity)
             .expect("The entity is not in this Archetype!");
         let mut removed_entity: Option<(Entity, ArchetypeEntityId)> = None;
 
         for c in self.columns.iter_mut() {
             let moved_entity = unsafe { c.remove_component(entity_index.0 as usize, tick) };
 
-            if let Some(res) = moved_entity {
+            if let Some(moved_idx) = moved_entity {
                 if let Some((_, aid)) = removed_entity {
                     // Make sure that the moved entity is the same as what was moved in other columns.
-                    assert!(res as u64 == aid.0);
+                    assert!(moved_idx as u64 == aid.0);
                 } else {
-                    // This is the first move, so find the EntityId that points to the column index.
+                    // This is the first move, so find the Entity that was moved into this index.
-                    let just_removed = self.entities[res];
+                    let just_removed = self.entities[moved_idx];
-                    removed_entity = Some((just_removed, ArchetypeEntityId(res as u64)));
+                    removed_entity = Some((just_removed, ArchetypeEntityId(moved_idx as u64)));
                 }
             } else {
                 // If there wasn't a moved entity, make sure no other columns moved something. 
@@ -316,12 +332,15 @@ impl Archetype {
         }
 
         // safe from the .expect at the start of this method.
-        self.entity_ids.remove(&entity).unwrap();
+        //self.entity_ids.remove(&entity).unwrap();
-        if self.entities.len() > 1 {
+        
-            let len = self.entities.len();
+        // update the archetype index of the moved entity
-            self.entities.swap(entity_index.0 as _,  len - 1);
+        if let Some((moved, _old_idx)) = removed_entity {
+            self.entity_ids.insert(moved, entity_index);
         }
-        self.entities.pop().unwrap();
+        
+        let removed = self.entities.swap_remove(entity_index.0 as _);
+        assert_eq!(removed, entity);
         
         // now change the ArchetypeEntityId to be the index that the moved entity was moved into.
         removed_entity.map(|(e, _a)| (e, entity_index))
@@ -390,7 +409,8 @@ impl Archetype {
             self.capacity = new_cap;
         }
 
-        debug_assert_eq!(self.entity_ids.len(), self.entities.len(), "Somehow the Archetype's entity storage got unsynced");
+        debug_assert_eq!(self.entity_ids.len(), self.entities.len(),
+            "Somehow the Archetype's entity storage got unsynced");
         let entity_index = ArchetypeEntityId(self.entity_ids.len() as u64);
         self.entity_ids.insert(entity, entity_index);
         self.entities.push(entity);
@@ -402,6 +422,12 @@ impl Archetype {
         entity_index
     }
 
+    /// Ensure that the internal entity lists are synced in length
+    pub(crate) fn ensure_synced(&self) {
+        debug_assert_eq!(self.entity_ids.len(), self.entities.len(),
+            "Somehow the Archetype's entity storage got unsynced");
+    }
+
     /// Moves the entity from this archetype into another one.
     /// 
     /// # Safety
@@ -453,6 +479,36 @@ impl Archetype {
     pub fn has_entity(&self, e: Entity) -> bool {
         self.entity_ids.contains_key(&e)
     }
+
+    /// Extend the Archetype by adding more columns.
+    /// 
+    /// In order to extend the Archetype, the archetype needs the components for the entities
+    /// it already has. These are provided through the `new_columns` parameter. **If the Vec
+    /// does not have the same amount of bundles in it as the amount of entities in the
+    /// Archetype, it will panic!**
+    pub fn extend<B: Bundle>(&mut self, tick: &Tick, new_columns: Vec<B>) {
+        debug_assert_eq!(new_columns.len(), self.len(), "The amount of provided column does not \
+            match the amount of entities");
+        
+        let column_info = new_columns.iter()
+            .next()
+            .unwrap()
+            .info();
+
+        for coli in column_info.into_iter() {
+            let col = unsafe { ComponentColumn::new(coli, self.capacity) };
+            self.columns.push(col);
+        }
+
+        for (eid, bundle) in new_columns.into_iter().enumerate() {
+            bundle.take(|ptr, tyid, _size| {
+                unsafe {
+                    let col = self.get_column_mut(tyid).unwrap();
+                    col.insert_entity(eid, ptr, tick.clone());
+                }
+            });
+        }
+    }
 }
 
 #[cfg(test)]
@@ -666,4 +722,24 @@ mod tests {
         assert_eq!(unsafe { *ptr.cast::<u32>().as_ref() }, comp);
         assert_eq!(col.info, info);
     }
+
+    /// Tests removing an entity from the Archetype when it is the only entity in it.
+    #[test]
+    fn remove_single_entity() {
+        let info = (Vec2::new(0.0, 0.0),).info();
+        let mut a = Archetype::from_bundle_info(super::ArchetypeId(0), info);
+
+        let ae = Entity {
+            id: EntityId(0),
+            generation: 0
+        };
+
+        a.add_entity(
+            ae,
+            Vec2::new(10.0, 50.0),
+            &Tick::default()
+        );
+
+        a.remove_entity(ae, &Tick::default());
+    }
 }

lyra-ecs/src/lib.rs

@@ -30,7 +30,7 @@ pub use component::*;
 pub mod query;
 //pub use query::*;
 
-mod relation;
+pub mod relation;
 pub use relation::Relation;
 
 mod component_info;

lyra-ecs/src/query/borrow.rs

@@ -177,10 +177,10 @@ where
     unsafe fn fetch<'a>(&self, _world: &'a World, archetype: &'a crate::archetype::Archetype, tick: crate::Tick) -> Self::Fetch<'a> {
         let col = archetype.get_column(self.type_id)
             .expect("You ignored 'can_visit_archetype'!");
-        let col = NonNull::from(col);
         
         // TODO: find a way to get the component column mutable with a borrowed archetype so its tick can be updated.
         // the fetcher needs to tick the entities tick in the archetype
+        let col = NonNull::from(col);
 
         FetchBorrowMut {
             col,

lyra-ecs/src/query/filter/has_component.rs

@@ -0,0 +1,40 @@
+use std::marker::PhantomData;
+
+use crate::{query::{AsQuery, Query}, Archetype, Component, DynTypeId, World};
+
+#[derive(Default)]
+pub struct Has<C: Component> {
+    _marker: PhantomData<C>
+}
+
+impl<C: Component> Copy for Has<C> {}
+
+impl<C: Component> Clone for Has<C> {
+    fn clone(&self) -> Self {
+        Self { _marker: self._marker.clone() }
+    }
+}
+
+impl<C: Component> Query for Has<C> {
+    type Item<'a> = ();
+    
+    type Fetch<'a> = ();
+
+    fn new() -> Self {
+        Has {
+            _marker: PhantomData
+        }
+    }
+
+    fn can_visit_archetype(&self, archetype: &Archetype) -> bool {
+        archetype.has_column(DynTypeId::of::<C>())
+    }
+
+    unsafe fn fetch<'a>(&self, _world: &'a World, _: &'a Archetype, _: crate::Tick) -> Self::Fetch<'a> {
+        ()
+    }
+}
+
+impl<C: Component> AsQuery for Has<C> {
+    type Query = Self;
+}

lyra-ecs/src/query/filter/mod.rs

@@ -0,0 +1,5 @@
+pub mod has_component;
+pub use has_component::*;
+
+pub mod or;
+pub use or::*;

lyra-ecs/src/query/filter/or.rs

@@ -0,0 +1,40 @@
+use crate::{query::{AsQuery, Query}, Archetype, World};
+
+#[derive(Default)]
+pub struct Or<Q1: AsQuery, Q2: AsQuery> {
+    left: Q1::Query,
+    right: Q2::Query,
+}
+
+impl<Q1: AsQuery, Q2: AsQuery> Copy for Or<Q1, Q2> {}
+
+impl<Q1: AsQuery, Q2: AsQuery> Clone for Or<Q1, Q2> {
+    fn clone(&self) -> Self {
+        Self { left: self.left.clone(), right: self.right.clone() }
+    }
+}
+
+impl<Q1: AsQuery, Q2: AsQuery> Query for Or<Q1, Q2> {
+    type Item<'a> = ();
+    
+    type Fetch<'a> = ();
+
+    fn new() -> Self {
+        Or {
+            left: Q1::Query::new(),
+            right: Q2::Query::new(),
+        }
+    }
+
+    fn can_visit_archetype(&self, archetype: &Archetype) -> bool {
+        self.left.can_visit_archetype(archetype) || self.right.can_visit_archetype(archetype)
+    }
+
+    unsafe fn fetch<'a>(&self, _world: &'a World, _: &'a Archetype, _: crate::Tick) -> Self::Fetch<'a> {
+        ()
+    }
+}
+
+impl<Q1: AsQuery, Q2: AsQuery> AsQuery for Or<Q1, Q2> {
+    type Query = Self;
+}

lyra-ecs/src/query/mod.rs

@@ -29,6 +29,8 @@ pub use world::*;
 
 pub mod dynamic;
 
+pub mod filter;
+
 /// A [`Fetch`]er implementation gets data out of an archetype.
 pub trait Fetch<'a> {
     /// The type that this Fetch yields

lyra-ecs/src/query/view.rs

@@ -90,7 +90,7 @@ where
 
     fn next(&mut self) -> Option<Self::Item> {
         loop {
-            if Q::ALWAYS_FETCHES && F::ALWAYS_FETCHES {
+            if Q::ALWAYS_FETCHES {
                 // only fetch this query once.
                 // fetcher gets set to Some after this `next` call.
                 if self.fetcher.is_none() {

lyra-ecs/src/relation/child_of.rs

@@ -0,0 +1,8 @@
+use super::Relation;
+
+// TODO: Delete child entities when the parent is deleted
+pub struct ChildOf;
+
+impl Relation for ChildOf {
+    
+}

lyra-ecs/src/relation/mod.rs

@@ -10,19 +10,20 @@ use crate::lyra_engine;
 use crate::World;
 
 mod relates_to;
-#[doc(hidden)]
 pub use relates_to::*;
 
 mod relate_pair;
-#[doc(hidden)]
 pub use relate_pair::*;
 
+mod child_of;
+pub use child_of::*;
+
 #[allow(unused_variables)]
 pub trait Relation: 'static {
     /// called when a relation of this type is set on a target
-    fn relation_add(&self, origin: Entity, target: Entity) { }
+    fn relation_add(&mut self, world: &mut World, origin: Entity, target: Entity) { }
     /// called when a relation is removed
-    fn relation_remove(&self, origin: Entity, target: Entity) { }
+    fn relation_remove(&mut self, world: &mut World, origin: Entity, target: Entity) { }
 }
 
 /// A component that stores the target of a relation.
@@ -31,10 +32,16 @@ pub trait Relation: 'static {
 /// entities that the relation targets.
 #[derive(Component)]
 pub struct RelationOriginComponent<R: Relation> {
-    pub(crate) relation: R,
+    pub relation: R,
     target: Entity,
 }
 
+impl<R: Relation> RelationOriginComponent<R> {
+    pub fn target(&self) -> Entity {
+        self.target
+    }
+}
+
 /// A component that stores the origin of a relation.
 /// 
 /// This component is on the target of the relation and can be used to find the
@@ -79,12 +86,12 @@ impl World {
         };
         self.insert(target, comp);
 
-        let comp = RelationOriginComponent {
+        let mut comp = RelationOriginComponent {
             relation,
             target,
         };
         
-        comp.relation.relation_add(origin, target);
+        comp.relation.relation_add(self, origin, target);
         self.insert(origin, comp);
     }
 }

lyra-ecs/src/relation/relate_pair.rs

@@ -69,7 +69,7 @@ where
 
     unsafe fn fetch<'a>(&self, _world: &'a World, archetype: &'a crate::archetype::Archetype, tick: crate::Tick) -> Self::Fetch<'a> {
         let _ = tick;
-        let col = archetype.get_column(self.type_id())
+        let col = archetype.get_column(TypeId::of::<RelationOriginComponent<R>>())
             .expect("You ignored 'can_visit_archetype'!");
 
         FetchRelatePair {

lyra-ecs/src/world.rs

@@ -133,8 +133,6 @@ impl World {
     where
         B: Bundle
     {
-        // TODO: If the archetype has a single entity, add a component column for the new
-        // component instead of moving the entity to a brand new archetype.
         // TODO: If the entity already has the components in `bundle`, update the values of the
         // components with the bundle.
 
@@ -142,6 +140,7 @@ impl World {
 
         let record = self.entities.entity_record(entity).unwrap();
         let current_arch = self.archetypes.get(&record.id).unwrap();
+        let current_arch_len = current_arch.len();
 
         let mut col_types: Vec<DynTypeId> = current_arch.columns.iter().map(|c| c.info.type_id()).collect();
         let orig_col = col_types.clone();
@@ -150,7 +149,9 @@ impl World {
         let mut col_infos: Vec<ComponentInfo> = current_arch.columns.iter().map(|c| c.info).collect();
         col_infos.extend(bundle.info());
 
-        let col_ptrs: Vec<(NonNull<u8>, ComponentInfo)> = current_arch.columns.iter().map(|c| unsafe { (NonNull::new_unchecked(c.borrow_ptr().as_ptr()), c.info) }).collect();
+        let col_ptrs: Vec<(NonNull<u8>, ComponentInfo)> = current_arch.columns.iter()
+            .map(|c| unsafe { (NonNull::new_unchecked(c.borrow_ptr().as_ptr()), c.info) })
+            .collect();
 
         if let Some(arch) = self.archetypes.values_mut().find(|a| a.is_archetype_for(&col_types)) {
             let res_index = arch.reserve_one(entity);
@@ -158,19 +159,21 @@ impl World {
             for (col_type, (col_ptr, col_info)) in orig_col.into_iter().zip(col_ptrs.into_iter()) {
                 unsafe {
                     let ptr = NonNull::new_unchecked(col_ptr.as_ptr()
-                        .add(res_index.0 as usize * col_info.layout().size()));
+                        .add(record.index.0 as usize * col_info.layout().size()));
                     let col = arch.get_column_mut(col_type).unwrap();
+                    // set_at is used since the entity was reserved
                     col.set_at(res_index.0 as _, ptr, tick);
                 }
             }
 
             bundle.take(|data, type_id, _size| {
                 let col = arch.get_column_mut(type_id).unwrap();
+                // set_at is used since the entity was reserved
                 unsafe { col.set_at(res_index.0 as _, data, tick); }
-                col.len += 1;
             });
 
             arch.entity_ids.insert(entity, res_index);
+            arch.ensure_synced();
             
             let new_record = Record {
                 id: arch.id(),
@@ -178,10 +181,30 @@ impl World {
             };
             self.entities.insert_entity_record(entity, new_record);
         } else {
+            if current_arch_len == 1 {
+                // if this entity is the only entity for this archetype, add more columns to it
+                let current_arch = self.archetypes.get_mut(&record.id).unwrap();
+                current_arch.extend(&tick, vec![bundle]);
+
+                return;
+            }
+
             let new_arch_id = self.next_archetype_id.increment();
             let mut archetype = Archetype::from_bundle_info(new_arch_id, col_infos);
             let entity_arch_id = archetype.add_entity(entity, bundle, &tick);
             
+            // move the old components into the new archetype
+            for (column_ptr, column_info) in col_ptrs.into_iter() {
+                unsafe {
+                    // ptr of component for the entity
+                    let comp_ptr = NonNull::new_unchecked(column_ptr.as_ptr()
+                        .add(record.index.0 as usize * column_info.layout().size()));
+                    
+                    let col = archetype.get_column_mut(column_info.type_id()).unwrap();
+                    col.insert_entity(entity_arch_id.0 as _, comp_ptr, tick);
+                }
+            }
+
             self.archetypes.insert(new_arch_id, archetype);
 
             // Create entity record and store it
@@ -194,7 +217,13 @@ impl World {
         }
 
         let current_arch = self.archetypes.get_mut(&record.id).unwrap();
+        if current_arch.len() > 1 {
             current_arch.remove_entity(entity, &tick);
+        } else if current_arch.len() == 1 {
+            // The old archetype will only be removed if there was another archetype that would
+            // work for the entity's components, and the old archetype only had a single entity.
+            self.archetypes.remove(&record.id).unwrap();
+        }
     }
 
     pub fn entity_archetype(&self, entity: Entity) -> Option<&Archetype> {
@@ -225,6 +254,13 @@ impl World {
         v.into_iter()
     }
 
+    /// View into the world for a set of entities that satisfy the queries.
+    pub fn filtered_view_iter<Q: AsQuery, F: AsQuery>(&self) -> ViewIter<Q::Query, F::Query> {
+        let archetypes = self.archetypes.values().collect();
+        let v = ViewState::new(self, Q::Query::new(), F::Query::new(), archetypes);
+        v.into_iter()
+    }
+
     pub fn dynamic_view(&self) -> DynamicView {
         DynamicView::new(self)
     }
@@ -330,7 +366,7 @@ impl World {
 
 #[cfg(test)]
 mod tests {
-    use crate::{tests::{Vec2, Vec3}, query::TickOf};
+    use crate::{query::TickOf, tests::{Vec2, Vec3}, Entity};
 
     use super::World;
 
@@ -453,6 +489,46 @@ mod tests {
         assert!(world.view_one::<&Vec3>(e).get().is_some())
     }
 
+    #[test]
+    fn insert_multiple_times() {
+        let v2s = &[Vec2::rand(), Vec2::rand(), Vec2::rand()];
+        let v3s = &[Vec3::rand(), Vec3::rand(), Vec3::rand()];
+
+        let mut world = World::new();
+        let e1 = world.spawn(v2s[0]);
+        let e2 = world.spawn(v2s[1]);
+        let e3 = world.spawn(v2s[2]);
+        println!("Spawned entities");
+
+        let ev2 = world.view_one::<&Vec2>(e2).get()
+            .expect("Failed to find Vec2 and Vec3 on inserted entity!");
+        assert_eq!(*ev2, v2s[1]);
+        drop(ev2);
+
+        let insert_and_assert = |world: &mut World, e: Entity, v2: Vec2, v3: Vec3| {
+            println!("inserting entity");
+            world.insert(e, (v3,));
+            println!("inserted entity");
+
+            let (ev2, ev3) = world.view_one::<(&Vec2, &Vec3)>(e).get()
+                .expect("Failed to find Vec2 and Vec3 on inserted entity!");
+            assert_eq!(*ev2, v2);
+            assert_eq!(*ev3, v3);
+        };
+
+        insert_and_assert(&mut world, e2, v2s[1], v3s[1]);
+        println!("Entity 2 is good");
+        insert_and_assert(&mut world, e3, v2s[2], v3s[2]);
+        println!("Entity 3 is good");
+        assert_eq!(world.archetypes.len(), 2);
+        println!("No extra archetypes were created");
+
+        insert_and_assert(&mut world, e1, v2s[0], v3s[0]);
+        println!("Entity 1 is good");
+        assert_eq!(world.archetypes.len(), 1);
+        println!("Empty archetype was removed");
+    }
+
     #[test]
     fn view_one() {
         let v = Vec2::rand();
@@ -468,11 +544,6 @@ mod tests {
     fn view_change_tracking() {
         let mut world = World::new();
 
-        /* let v = Vec2::rand();
-        world.spawn((v,));
-        let v = Vec2::rand();
-        world.spawn((v,)); */
-
         println!("spawning");
         world.spawn((Vec2::new(10.0, 10.0),));
         world.spawn((Vec2::new(5.0, 5.0),));

lyra-game/src/render/material.rs

@@ -1,5 +1,7 @@
 use std::sync::Arc;
 
+use lyra_resource::{ResHandle, Texture};
+
 use super::texture::RenderTexture;
 
 pub struct MaterialSpecular {
@@ -9,13 +11,18 @@ pub struct MaterialSpecular {
     pub color_texture: Option<RenderTexture>,
 }
 
-impl MaterialSpecular {
+fn texture_to_render(device: &wgpu::Device, queue: &wgpu::Queue, bg_layout: &Arc<wgpu::BindGroupLayout>, i: &Option<ResHandle<Texture>>) -> Option<RenderTexture> {
-    pub fn from_resource(device: &wgpu::Device, queue: &wgpu::Queue, bg_layout: Arc<wgpu::BindGroupLayout>, value: &lyra_resource::Specular) -> Self {
+    if let Some(tex) = i {
-        let tex = value.texture.as_ref().map(|t| t.data_ref())
+        RenderTexture::from_resource(device, queue, bg_layout.clone(), tex, None).ok()
-            .map(|i| RenderTexture::from_image(device, queue, bg_layout.clone(), &i.image, None).unwrap());
+    } else {
+        None
+    }
+}
 
-        let color_tex = value.color_texture.as_ref().map(|t| t.data_ref())
+impl MaterialSpecular {
-            .map(|i| RenderTexture::from_image(device, queue, bg_layout, &i.image, None).unwrap());
+    pub fn from_resource(device: &wgpu::Device, queue: &wgpu::Queue, bg_layout: Arc<wgpu::BindGroupLayout>, value: &lyra_resource::gltf::Specular) -> Self {
+        let tex  = texture_to_render(device, queue, &bg_layout, &value.texture);
+        let color_tex  = texture_to_render(device, queue, &bg_layout, &value.color_texture);
 
         Self {
             factor: value.factor,
@@ -38,9 +45,8 @@ pub struct Material {
 }
 
 impl Material {
-    pub fn from_resource(device: &wgpu::Device, queue: &wgpu::Queue, bg_layout: Arc<wgpu::BindGroupLayout>, value: &lyra_resource::Material) -> Self {
+    pub fn from_resource(device: &wgpu::Device, queue: &wgpu::Queue, bg_layout: Arc<wgpu::BindGroupLayout>, value: &lyra_resource::gltf::Material) -> Self {
-        let diffuse_texture = value.base_color_texture.as_ref().map(|t| t.data_ref())
+        let diffuse_texture  = texture_to_render(device, queue, &bg_layout, &value.base_color_texture);
-            .map(|i| RenderTexture::from_image(device, queue, bg_layout.clone(), &i.image, None).unwrap());
 
         let specular = value.specular.as_ref().map(|s| MaterialSpecular::from_resource(device, queue, bg_layout.clone(), s));
 

lyra-game/src/render/render_job.rs

@@ -1,21 +1,17 @@
 use lyra_ecs::Entity;
 
-use crate::math::Transform;
-
 pub struct RenderJob {
     pub entity: Entity,
     pub shader_id: u64,
-    pub mesh_buffer_id: uuid::Uuid,
+    pub mesh_uuid: uuid::Uuid,
-    pub transform: Transform,
 }
 
 impl RenderJob {
-    pub fn new(entity: Entity, shader_id: u64, mesh_buffer_id: uuid::Uuid, transform: Transform) -> Self {
+    pub fn new(entity: Entity, shader_id: u64, mesh_buffer_id: uuid::Uuid) -> Self {
         Self {
             entity,
             shader_id,
-            mesh_buffer_id,
+            mesh_uuid: mesh_buffer_id,
-            transform,
         }
     }
 }

lyra-game/src/render/renderer.rs

@@ -5,10 +5,13 @@ use std::borrow::Cow;
 use glam::Vec3;
 use instant::Instant;
 use itertools::izip;
-use lyra_ecs::Entity;
+use lyra_ecs::query::filter::{Has, Or};
+use lyra_ecs::{Entity, Tick};
 use lyra_ecs::query::{Entities, TickOf};
 use lyra_ecs::World;
+use lyra_resource::gltf::GltfScene;
 use tracing::{debug, warn};
+use uuid::Uuid;
 use wgpu::{BindGroupLayout, Limits};
 use wgpu::util::DeviceExt;
 use winit::window::Window;
@@ -16,7 +19,7 @@ use winit::window::Window;
 use crate::math::Transform;
 use crate::render::material::MaterialUniform;
 use crate::render::render_buffer::BufferWrapperBuilder;
-use crate::scene::{ModelComponent, CameraComponent};
+use crate::scene::CameraComponent;
 
 use super::camera::{RenderCamera, CameraUniform};
 use super::desc_buf_lay::DescVertexBufferLayout;
@@ -28,7 +31,10 @@ use super::transform_buffer_storage::TransformBuffers;
 use super::vertex::Vertex;
 use super::{render_pipeline::FullRenderPipeline, render_buffer::BufferStorage, render_job::RenderJob};
 
-use lyra_resource::Mesh;
+use lyra_resource::{gltf::Mesh, ResHandle};
+
+type MeshHandle = ResHandle<Mesh>;
+type SceneHandle = ResHandle<GltfScene>;
 
 pub trait Renderer {
     fn prepare(&mut self, main_world: &mut World);
@@ -265,16 +271,19 @@ impl BasicRenderer {
         s
     }
 
-    fn update_mesh_buffers(&mut self, _entity: Entity, mesh: &Mesh) {
+    /// Checks if the mesh buffers in the GPU need to be updated.
-        if let Some(buffers) = self.mesh_buffers.get_mut(&mesh.uuid) {
+    fn check_mesh_buffers(&mut self, _entity: Entity, meshh: &ResHandle<Mesh>) {
+        let mesh_uuid = meshh.uuid();
+
+        if let (Some(mesh), Some(buffers)) = (meshh.data_ref(), self.mesh_buffers.get_mut(&mesh_uuid)) {
             // check if the buffer sizes dont match. If they dont, completely remake the buffers
             let vertices = mesh.position().unwrap();
             if buffers.buffer_vertex.count() != vertices.len() {
-                debug!("Recreating buffers for mesh {}", mesh.uuid.to_string());
+                debug!("Recreating buffers for mesh {}", mesh_uuid.to_string());
-                let (vert, idx) = self.create_vertex_index_buffers(mesh);
+                let (vert, idx) = self.create_vertex_index_buffers(&mesh);
 
                 // have to re-get buffers because of borrow checker
-                let buffers = self.mesh_buffers.get_mut(&mesh.uuid).unwrap();
+                let buffers = self.mesh_buffers.get_mut(&mesh_uuid).unwrap();
                 buffers.buffer_indices = idx;
                 buffers.buffer_vertex = vert;
 
@@ -292,8 +301,8 @@ impl BasicRenderer {
             if let Some(index_buffer) = buffers.buffer_indices.as_ref() {
                 let aligned_indices = match mesh.indices.as_ref().unwrap() {
                     // U16 indices need to be aligned to u32, for wpgu, which are 4-bytes in size.
-                    lyra_resource::MeshIndices::U16(v) => bytemuck::pod_align_to::<u16, u32>(v).1,
+                    lyra_resource::gltf::MeshIndices::U16(v) => bytemuck::pod_align_to::<u16, u32>(v).1,
-                    lyra_resource::MeshIndices::U32(v) => bytemuck::pod_align_to::<u32, u32>(v).1,
+                    lyra_resource::gltf::MeshIndices::U32(v) => bytemuck::pod_align_to::<u32, u32>(v).1,
                 };
                 
                 let index_buffer = index_buffer.1.buffer();
@@ -327,8 +336,8 @@ impl BasicRenderer {
         let indices = match mesh.indices.as_ref() {
             Some(indices) => {
                 let (idx_type, len, contents) = match indices {
-                    lyra_resource::MeshIndices::U16(v) => (wgpu::IndexFormat::Uint16, v.len(), bytemuck::cast_slice(v)),
+                    lyra_resource::gltf::MeshIndices::U16(v) => (wgpu::IndexFormat::Uint16, v.len(), bytemuck::cast_slice(v)),
-                    lyra_resource::MeshIndices::U32(v) => (wgpu::IndexFormat::Uint32, v.len(), bytemuck::cast_slice(v)),
+                    lyra_resource::gltf::MeshIndices::U32(v) => (wgpu::IndexFormat::Uint32, v.len(), bytemuck::cast_slice(v)),
                 };
 
                 let index_buffer = self.device.create_buffer_init(
@@ -354,7 +363,11 @@ impl BasicRenderer {
     fn create_mesh_buffers(&mut self, mesh: &Mesh) -> MeshBufferStorage {
         let (vertex_buffer, buffer_indices) = self.create_vertex_index_buffers(mesh);
 
-        let material = Material::from_resource(&self.device, &self.queue, self.bgl_texture.clone(), &mesh.material());
+        let material = mesh.material.as_ref()
+            .expect("Material resource not loaded yet")
+            .data_ref()
+            .unwrap();
+        let material = Material::from_resource(&self.device, &self.queue, self.bgl_texture.clone(), &material);
         let uni = MaterialUniform::from(&material);
         self.queue.write_buffer(&self.material_buffer.inner_buf, 0, bytemuck::bytes_of(&uni));
         debug!("Wrote material to buffer");
@@ -367,24 +380,57 @@ impl BasicRenderer {
     }
 
     /// Processes the mesh for the renderer, storing and creating buffers as needed. Returns true if a new mesh was processed.
-    fn process_mesh(&mut self, entity: Entity, transform: Transform, mesh: &Mesh) -> bool {
+    fn process_mesh(&mut self, entity: Entity, transform: Transform, mesh: &Mesh, mesh_uuid: Uuid) -> bool {
         if self.transform_buffers.should_expand() {
             self.transform_buffers.expand_buffers(&self.device);
         }
 
         self.transform_buffers.update_or_insert(&self.queue, &self.render_limits,
-            entity, || ( transform.calculate_mat4(), glam::Mat3::from_quat(transform.rotation) ));
+            mesh_uuid, || ( transform.calculate_mat4(), glam::Mat3::from_quat(transform.rotation) ));
 
         #[allow(clippy::map_entry)]
-        if !self.mesh_buffers.contains_key(&mesh.uuid) {
+        if !self.mesh_buffers.contains_key(&mesh_uuid) {
             // create the mesh's buffers
             let buffers = self.create_mesh_buffers(mesh);
-            self.mesh_buffers.insert(mesh.uuid, buffers);
+            self.mesh_buffers.insert(mesh_uuid, buffers);
-            self.entity_meshes.insert(entity, mesh.uuid);
+            self.entity_meshes.insert(entity, mesh_uuid);
 
             true
         } else { false }
     }
+
+    fn interpolate_transforms(&mut self, now: Instant, last_epoch: Tick, entity: Entity, transform: &Transform, transform_epoch: Tick) -> Transform {
+        let cached = match self.entity_last_transforms.get_mut(&entity) {
+            Some(last) if transform_epoch == last_epoch => {
+                last.from_transform = last.to_transform;
+                last.to_transform = *transform;
+                last.last_updated_at = Some(last.cached_at);
+                last.cached_at = now;
+
+                last.clone()
+            },
+            Some(last) => last.clone(),
+            None => {
+                let cached = CachedTransform {
+                    last_updated_at: None,
+                    cached_at: now,
+                    from_transform: *transform,
+                    to_transform: *transform,
+                };
+                self.entity_last_transforms.insert(entity, cached.clone());
+                cached
+            }
+        };
+        
+        let fixed_time = match cached.last_updated_at {
+            Some(last_updated_at) => cached.cached_at - last_updated_at,
+            None => now - cached.cached_at
+        }.as_secs_f32();
+        let accumulator = (now - cached.cached_at).as_secs_f32();
+        let alpha = accumulator / fixed_time;
+
+        cached.from_transform.lerp(cached.to_transform, alpha)
+    }
 }
 
 impl Renderer for BasicRenderer {
@@ -395,56 +441,61 @@ impl Renderer for BasicRenderer {
         
         let now_inst = Instant::now();
         
-        for (entity, model, model_epoch, transform, transform_epoch) in main_world.view_iter::<(Entities, &ModelComponent, TickOf<ModelComponent>, &Transform, TickOf<Transform>)>() {
+        let view = main_world.filtered_view_iter::<(Entities, &Transform, TickOf<Transform>), Or<Has<MeshHandle>, Has<SceneHandle>>>();
+        for (entity, transform, transform_epoch) in view {
             alive_entities.insert(entity);
 
-            let cached = match self.entity_last_transforms.get_mut(&entity) {
+            let mesh_view = main_world.view_one::<(&MeshHandle, TickOf<MeshHandle>)>(entity);
-                Some(last) if transform_epoch == last_epoch => {
+            if let Some((mesh_han, mesh_epoch)) = mesh_view.get() {
-                    last.from_transform = last.to_transform;
+                let interop_pos = self.interpolate_transforms(now_inst, last_epoch, entity, &transform, transform_epoch);
-                    last.to_transform = *transform;
-                    last.last_updated_at = Some(last.cached_at);
-                    last.cached_at = now_inst;
 
-                    last.clone()
+                if let Some(mesh) = mesh_han.data_ref() {
-                },
+                    // if process mesh did not just create a new mesh, and the epoch
-                Some(last) => last.clone(),
+                    // shows that the scene has changed, verify that the mesh buffers
-                None => {
+                    // dont need to be resent to the gpu.
-                    let cached = CachedTransform {
+                    if !self.process_mesh(entity, interop_pos, &*mesh, mesh_han.uuid())
-                        last_updated_at: None,
+                            && mesh_epoch == last_epoch {
-                        cached_at: now_inst,
+                        self.check_mesh_buffers(entity, &mesh_han);
-                        from_transform: *transform,
-                        to_transform: *transform,
-                    };
-                    self.entity_last_transforms.insert(entity, cached.clone());
-                    cached
-                }
-            };
-            //debug!("Transform: {:?}, comp: {:?}", cached.to_transform.translation, transform.transform.translation);
-            
-            let fixed_time = match cached.last_updated_at {
-                Some(last_updated_at) => cached.cached_at - last_updated_at,
-                None => now_inst - cached.cached_at
-            }.as_secs_f32();
-            let accumulator = (now_inst - cached.cached_at).as_secs_f32();
-            let alpha = accumulator / fixed_time;
-
-            let transform_val = cached.from_transform.lerp(cached.to_transform, alpha);
-
-            let model = model.data_ref();
-            for mesh in model.meshes.iter() {
-                if !self.process_mesh(entity, transform_val, mesh) && model_epoch == last_epoch {
-                    self.update_mesh_buffers(entity, mesh);
                     }
                     
-                let shader = mesh.material().shader_uuid.unwrap_or(0);
+                    let material = mesh.material.as_ref().unwrap()
-                let job = RenderJob::new(entity, shader, mesh.uuid, transform_val);
+                        .data_ref().unwrap();
+                    let shader = material.shader_uuid.unwrap_or(0);
+                    let job = RenderJob::new(entity, shader, mesh_han.uuid());
                     self.render_jobs.push_back(job);
                 }
             }
 
-        /* for (entity, mesh, mesh_epoch, transform) in main_world.query::<(Entities, &MeshComponent, EpochOf<MeshComponent>, &TransformComponent)>().iter() {
+            let scene_view = main_world.view_one::<(&SceneHandle, TickOf<SceneHandle>)>(entity);
-            debug!("TODO: Process MeshComponents"); // TODO: Process MeshComponents
+            if let Some((scene_han, scene_epoch)) = scene_view.get() {
-        } */
+                // TODO: Rendering scenes
+
+                if let Some(scene) = scene_han.data_ref() {
+                    let interpo_pos = self.interpolate_transforms(now_inst, last_epoch, entity, &transform, transform_epoch);
+                    let meshes = scene.collect_world_meshes();
+
+                    for (mesh_han, mesh_pos) in meshes.into_iter() {
+                        if let Some(mesh) = mesh_han.data_ref() {
+                            let mesh_interpo = interpo_pos + mesh_pos;
+
+                            // if process mesh did not just create a new mesh, and the epoch
+                            // shows that the scene has changed, verify that the mesh buffers
+                            // dont need to be resent to the gpu.
+                            if !self.process_mesh(entity, mesh_interpo, &*mesh, mesh_han.uuid())
+                                    && scene_epoch == last_epoch {
+                                self.check_mesh_buffers(entity, &mesh_han);
+                            }
+                            
+                            let material = mesh.material.as_ref().unwrap()
+                                .data_ref().unwrap();
+                            let shader = material.shader_uuid.unwrap_or(0);
+                            let job = RenderJob::new(entity, shader, mesh_han.uuid());
+                            self.render_jobs.push_back(job);
+                        }
+                    }
+                }
+            }
+        }
 
         // collect dead entities
         self.transform_buffers.tick();
@@ -513,7 +564,7 @@ impl Renderer for BasicRenderer {
                     render_pass.set_pipeline(pipeline.get_wgpu_pipeline());
 
                     // get the mesh (containing vertices) and the buffers from storage
-                    let buffers = self.mesh_buffers.get(&job.mesh_buffer_id).unwrap();
+                    let buffers = self.mesh_buffers.get(&job.mesh_uuid).unwrap();
 
                     // Bind the optional texture
                     if let Some(tex) = buffers.material.as_ref()
@@ -532,7 +583,7 @@ impl Renderer for BasicRenderer {
                     }
 
                     // Get the bindgroup for job's transform and bind to it using an offset.
-                    let transform_indices = *self.transform_buffers.entity_indices(job.entity).unwrap();
+                    let transform_indices = *self.transform_buffers.transform_indices(job.mesh_uuid).unwrap();
                     let bindgroup = self.transform_buffers.bind_group(transform_indices).unwrap();
                     let offset = TransformBuffers::index_offset(&self.render_limits, transform_indices) as u32;
                     render_pass.set_bind_group(1, bindgroup, &[ offset, offset, ]);

lyra-game/src/render/texture.rs

@@ -1,29 +1,10 @@
 use std::sync::Arc;
 
 use image::GenericImageView;
-use lyra_resource::{ResHandle, Texture};
+use lyra_resource::{FilterMode, ResHandle, Texture, WrappingMode};
 
 use super::render_buffer::BindGroupPair;
 
-/* #[derive(Clone)]
-pub struct Texture {
-    texture_id: u32,
-    pub img: image::DynamicImage,
-}
-
-impl Texture {
-    pub fn from_bytes(bytes: &[u8]) -> anyhow::Result<Self> {
-        let img = image::load_from_memory(bytes)?;
-
-        Ok(Self {
-            texture_id: 0,
-            img,
-        })
-    }
-} */
-
-
-
 #[allow(dead_code)]
 pub struct RenderTexture {
     pub inner_texture: wgpu::Texture,
@@ -153,8 +134,101 @@ impl RenderTexture {
         })
     }
 
-    pub fn update_texture(&mut self, _device: &wgpu::Device, queue: &wgpu::Queue, texture: &Arc<ResHandle<Texture>>) {
+    pub fn from_resource(device: &wgpu::Device, queue: &wgpu::Queue, bg_layout: Arc<wgpu::BindGroupLayout>, texture_res: &ResHandle<Texture>, label: Option<&str>) -> anyhow::Result<Self> {
-        let texture = &texture.data_ref().image;
+        let texture_ref = texture_res.data_ref().unwrap();
+        let img = texture_ref.image.data_ref().unwrap();
+
+        let rgba = img.to_rgba8();
+        let dimensions = img.dimensions();
+
+        let size = wgpu::Extent3d {
+            width: dimensions.0,
+            height: dimensions.1,
+            depth_or_array_layers: 1,
+        };
+        let texture = device.create_texture(
+            &wgpu::TextureDescriptor {
+                label,
+                size,
+                mip_level_count: 1,
+                sample_count: 1,
+                dimension: wgpu::TextureDimension::D2,
+                format: wgpu::TextureFormat::Rgba8UnormSrgb,
+                usage: wgpu::TextureUsages::TEXTURE_BINDING | wgpu::TextureUsages::COPY_DST,
+                view_formats: &[],
+            }
+        );
+
+        queue.write_texture(
+            wgpu::ImageCopyTexture {
+                aspect: wgpu::TextureAspect::All,
+                texture: &texture,
+                mip_level: 0,
+                origin: wgpu::Origin3d::ZERO,
+            },
+            &rgba,
+            wgpu::ImageDataLayout {
+                offset: 0,
+                bytes_per_row: std::num::NonZeroU32::new(4 * dimensions.0),
+                rows_per_image: std::num::NonZeroU32::new(dimensions.1),
+            },
+            size,
+        );
+
+        // convert resource sampler into wgpu sampler
+        let sampler_desc = match &texture_ref.sampler {
+            Some(sampler) => {
+                let magf = res_filter_to_wgpu(sampler.mag_filter.unwrap_or(FilterMode::Linear));
+                let minf = res_filter_to_wgpu(sampler.min_filter.unwrap_or(FilterMode::Nearest));
+                let mipf = res_filter_to_wgpu(sampler.mipmap_filter.unwrap_or(FilterMode::Nearest));
+
+                let wrap_u = res_wrap_to_wgpu(sampler.wrap_u);
+                let wrap_v = res_wrap_to_wgpu(sampler.wrap_v);
+                let wrap_w = res_wrap_to_wgpu(sampler.wrap_w);
+
+                wgpu::SamplerDescriptor {
+                    address_mode_u: wrap_u,
+                    address_mode_v: wrap_v,
+                    address_mode_w: wrap_w,
+                    mag_filter: magf,
+                    min_filter: minf,
+                    mipmap_filter: mipf,
+                    ..Default::default()
+                }
+            }
+            None => wgpu::SamplerDescriptor {
+                address_mode_u: wgpu::AddressMode::ClampToEdge,
+                address_mode_v: wgpu::AddressMode::ClampToEdge,
+                address_mode_w: wgpu::AddressMode::ClampToEdge,
+                mag_filter: wgpu::FilterMode::Linear,
+                min_filter: wgpu::FilterMode::Nearest,
+                mipmap_filter: wgpu::FilterMode::Nearest,
+                ..Default::default()
+            },
+        };
+
+        let view = texture.create_view(&wgpu::TextureViewDescriptor::default());
+        let sampler = device.create_sampler(
+            &sampler_desc
+        );
+        
+        let bgp = Self::create_bind_group_pair(device, bg_layout, &view, &sampler);
+
+        Ok(Self {
+            inner_texture: texture,
+            view,
+            sampler,
+            bindgroup_pair: Some(bgp),
+        })
+    }
+
+    /// Updates the texture on the gpu with the provided texture.
+    /// 
+    /// # Panics
+    /// Panics if `texture` is not loaded
+    pub fn update_texture(&mut self, _device: &wgpu::Device, queue: &wgpu::Queue, texture: &ResHandle<Texture>) {
+        let texture = &texture.data_ref().unwrap().image;
+        let texture = &texture.data_ref().unwrap();
         let rgba = texture.to_rgba8();
         let dimensions = texture.dimensions();
         let size = wgpu::Extent3d {
@@ -231,3 +305,22 @@ impl RenderTexture {
         &self.bindgroup_pair.as_ref().unwrap().bindgroup
     }
 }
+
+/// Convert [`lyra_resource::WrappingMode`] to [`wgpu::AddressMode`]
+#[inline(always)]
+fn res_wrap_to_wgpu(wmode: WrappingMode) -> wgpu::AddressMode {
+    match wmode {
+        WrappingMode::ClampToEdge => wgpu::AddressMode::ClampToEdge,
+        WrappingMode::MirroredRepeat => wgpu::AddressMode::MirrorRepeat,
+        WrappingMode::Repeat => wgpu::AddressMode::Repeat,
+    }
+}
+
+/// Convert [`lyra_resource::FilterMode`] to [`wgpu::FilterMode`]
+#[inline(always)]
+fn res_filter_to_wgpu(fmode: FilterMode) -> wgpu::FilterMode {
+    match fmode {
+        FilterMode::Nearest => wgpu::FilterMode::Nearest,
+        FilterMode::Linear => wgpu::FilterMode::Linear,
+    }
+}

lyra-game/src/render/transform_buffer_storage.rs

@@ -1,6 +1,6 @@
 use std::{collections::{VecDeque, HashMap}, num::NonZeroU64};
 
-use lyra_ecs::Entity;
+use uuid::Uuid;
 use wgpu::Limits;
 
 use std::mem;
@@ -19,11 +19,20 @@ pub(crate) struct TransformBufferEntry {
     pub bindgroup: wgpu::BindGroup,
 }
 
+/// A helper struct for managing the Transform buffers for meshes.
+/// 
+/// This struct manages a "chain" of uniform buffers that store Transform for meshes. When
+/// first created it only has a single "chain-link" with a buffer that is the maximum length
+/// the GPU supports. When the first buffer fills up, a new one should be created which will also
+/// be the maximum length the GPU supports. When the new buffer fills up, a new one will be
+/// created once again, and so on.
+/// 
+/// `Uuid`'s are used to represent entries (usually Meshes) in the buffer. The Uuid's can be used
+/// to insert, update, and retrieve the transforms.
 pub(crate) struct TransformBuffers {
     pub bindgroup_layout: wgpu::BindGroupLayout,
-    /// A vector storing the EntityId and 
+    pub just_updated: HashMap<Uuid, TransformBufferIndices>,
-    pub just_updated: HashMap<Entity, TransformBufferIndices>,
+    pub not_updated: HashMap<Uuid, TransformBufferIndices>,
-    pub not_updated: HashMap<Entity, TransformBufferIndices>,
     pub dead_indices: VecDeque<TransformBufferIndices>,
     pub next_indices: TransformBufferIndices,
     /// (transform count, buffer, bindgroup)
@@ -78,12 +87,15 @@ impl TransformBuffers {
         s
     }
 
-    /// Update an entity's buffer with the new transform. Will panic if the entity isn't stored
+    /// Update an transform in the buffer.
-    pub fn update_entity(&mut self, queue: &wgpu::Queue, limits: &Limits, entity: Entity, transform: glam::Mat4, normal_matrix: glam::Mat3) -> TransformBufferIndices {
+    /// 
-        let indices = self.not_updated.remove(&entity)
+    /// # Panics
-            .or_else(|| self.just_updated.remove(&entity))
+    /// Panics if the entity isn't stored, you can check if it is before with [`TransformBuffers:contains`].
+    pub fn update_transform(&mut self, queue: &wgpu::Queue, limits: &Limits, uuid: Uuid, transform: glam::Mat4, normal_matrix: glam::Mat3) -> TransformBufferIndices {
+        let indices = self.not_updated.remove(&uuid)
+            .or_else(|| self.just_updated.remove(&uuid))
             .expect("Use 'insert_entity' for new entities");
-        self.just_updated.insert(entity, indices);
+        self.just_updated.insert(uuid, indices);
 
         let normal_matrix = glam::Mat4::from_mat3(normal_matrix);
 
@@ -94,8 +106,8 @@ impl TransformBuffers {
         indices
     }
 
-    /// Insert a new entity into the buffer, returns where it was stored.
+    /// Insert a new transform into the buffer, returns where in the buffer it was stored.
-    pub fn insert_entity(&mut self, queue: &wgpu::Queue, limits: &Limits, entity: Entity, transform: glam::Mat4, normal_matrix: glam::Mat3) -> TransformBufferIndices {
+    pub fn insert_transform(&mut self, queue: &wgpu::Queue, limits: &Limits, uuid: Uuid, transform: glam::Mat4, normal_matrix: glam::Mat3) -> TransformBufferIndices {
         let indices = match self.dead_indices.pop_front() {
             Some(indices) => indices,
             None => {
@@ -113,28 +125,28 @@ impl TransformBuffers {
             }
         };
 
-        self.just_updated.insert(entity, indices);
+        self.just_updated.insert(uuid, indices);
-        self.update_entity(queue, limits, entity, transform, normal_matrix)
+        self.update_transform(queue, limits, uuid, transform, normal_matrix)
     }
 
-    /// Update or insert an entities transform
+    /// Update or insert a transform
-    pub fn update_or_insert<TFn>(&mut self, queue: &wgpu::Queue, limits: &Limits, entity: Entity, transform_fn: TFn) -> TransformBufferIndices
+    pub fn update_or_insert<TFn>(&mut self, queue: &wgpu::Queue, limits: &Limits, uuid: Uuid, transform_fn: TFn) -> TransformBufferIndices
         where TFn: Fn() -> (glam::Mat4, glam::Mat3)
     {   
         let (tran, norm) = transform_fn();
-        if self.contains(entity) {
+        if self.contains(uuid) {
-            self.update_entity(queue, limits, entity, tran, norm)
+            self.update_transform(queue, limits, uuid, tran, norm)
         } else {
-            self.insert_entity(queue, limits, entity, tran, norm)
+            self.insert_transform(queue, limits, uuid, tran, norm)
         }
     }
 
-    /// Returns true if the entity's transform is stored (does not mean its up-to-date).
+    /// Returns true if the transform related to the `uuid` is stored (does not mean its up-to-date).
-    pub fn contains(&self, entity: Entity) -> bool {
+    pub fn contains(&self, uuid: Uuid) -> bool {
-        self.not_updated.contains_key(&entity) || self.just_updated.contains_key(&entity)
+        self.not_updated.contains_key(&uuid) || self.just_updated.contains_key(&uuid)
     }
 
-    /// Collect the dead entities, mark entities and not updated for next updates.
+    /// Collect the dead transforms and prepare self to check next time.
     pub fn tick(&mut self) {
         // take the dead entities, these were ones that were not updated this tick
         let dead: VecDeque<TransformBufferIndices> = self.not_updated.values().copied().collect();
@@ -164,7 +176,10 @@ impl TransformBuffers {
             .map(|entry| &entry.bindgroup)
     }
 
-    /// Expand the Transform buffers by adding another uniform buffer binding
+    /// Expand the Transform buffers by adding another uniform buffer binding.
+    /// 
+    /// This object has a chain of uniform buffers, when the buffers are expanded, a new
+    /// "chain-link" is created.
     pub fn expand_buffers(&mut self, device: &wgpu::Device) {
         let limits = device.limits();
         let max_buffer_sizes = (limits.max_uniform_buffer_binding_size as u64) / 2;
@@ -228,7 +243,8 @@ impl TransformBuffers {
         self.buffer_bindgroups.push(entry);
     }
 
-    pub fn entity_indices(&self, entity: Entity) -> Option<&TransformBufferIndices> {
+    /// Returns the indices of the Transform 
-        self.just_updated.get(&entity).or_else(|| self.not_updated.get(&entity))
+    pub fn transform_indices(&self, uuid: Uuid) -> Option<&TransformBufferIndices> {
+        self.just_updated.get(&uuid).or_else(|| self.not_updated.get(&uuid))
     }
 }

lyra-game/src/scene/mesh.rs

@@ -1,15 +1,37 @@
 use lyra_ecs::Component;
-use lyra_resource::Mesh;
+use lyra_reflect::Reflect;
+use lyra_resource::{gltf::Mesh, ResHandle};
 
-#[derive(Clone, Component)]
+#[derive(Clone, Component, Reflect)]
 pub struct MeshComponent {
-    pub mesh: Mesh,
+    #[reflect(skip)]
+    pub mesh: ResHandle<Mesh>,
+}
+
+impl From<ResHandle<Mesh>> for MeshComponent {
+    fn from(value: ResHandle<Mesh>) -> Self {
+        Self {
+            mesh: value
+        }
+    }
+}
+
+impl std::ops::Deref for MeshComponent {
+    type Target = ResHandle<Mesh>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.mesh
+    }
+}
+
+impl std::ops::DerefMut for MeshComponent {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.mesh
+    }
 }
 
 impl MeshComponent {
-    pub fn new(mesh: Mesh) -> Self {
+    pub fn new(mesh: ResHandle<Mesh>) -> Self {
-        Self {
+        Self::from(mesh)
-            mesh,
-        }
     }
 }

lyra-game/src/scene/mod.rs

@@ -1,9 +1,6 @@
 pub mod mesh;
 pub use mesh::*;
 
-pub mod model;
-pub use model::*;
-
 pub mod camera;
 pub use camera::*;
 

lyra-game/src/scene/model.rs

@@ -1,41 +0,0 @@
-use lyra_ecs::Component;
-use lyra_reflect::Reflect;
-use lyra_resource::ResHandle;
-
-use crate::assets::Model;
-
-#[derive(Clone, Component, Reflect)]
-pub struct ModelComponent(#[reflect(skip)] pub ResHandle<Model>);
-
-impl From<ResHandle<Model>> for ModelComponent {
-    fn from(value: ResHandle<Model>) -> Self {
-        ModelComponent(value)
-    }
-}
-
-/* impl From<ResHandle<Model> for ModelComponent {
-
-} */
-
-impl std::ops::Deref for ModelComponent {
-    type Target = ResHandle<Model>;
-
-    fn deref(&self) -> &Self::Target {
-        &self.0
-    }
-}
-
-impl std::ops::DerefMut for ModelComponent {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.0
-    }
-}
-
-/* impl ModelComponent {
-    pub fn new(model, material: Material) -> Self {
-        Self {
-            mesh,
-            material
-        }
-    }
-} */

lyra-math/src/transform.rs

@@ -93,6 +93,13 @@ impl Transform {
         trans.z += z;
     }
 
+    /// Combines a transform with another one.
+    /// 
+    /// The translations are added while the rotations and scales are multiplied.
+    pub fn combine(self, rhs: Transform) -> Transform {
+        self + rhs
+    }
+    
     /// Performs a linear interpolation between `self` and `rhs` based on the value `alpha`.
     ///
     /// When `alpha` is `0.0`, the result will be equal to `self`.  When `alpha` is `1.0`, the result

lyra-resource/Cargo.toml

@@ -6,7 +6,8 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-lyra-ecs = { path = "../lyra-ecs" }
+lyra-ecs = { path = "../lyra-ecs", features = [ "math" ] }
+lyra-math = { path = "../lyra-math" }
 anyhow = "1.0.75"
 base64 = "0.21.4"
 crossbeam = { version = "0.8.4", features = [ "crossbeam-channel" ] }
@@ -23,3 +24,4 @@ percent-encoding = "2.3.0"
 thiserror = "1.0.48"
 tracing = "0.1.37"
 uuid = { version = "1.4.1", features = ["v4"] }
+instant = "0.1"

lyra-resource/src/gltf/loader.rs

@@ -1,8 +1,12 @@
 use std::{sync::Arc, path::PathBuf};
 
+use glam::{Quat, Vec3};
+use instant::Instant;
+use lyra_math::Transform;
 use thiserror::Error;
 
-use crate::{ResourceLoader, LoaderError, Mesh, Model, MeshVertexAttribute, VertexAttributeData, ResHandle, Material, MeshIndices, ResourceManager, util};
+use crate::{gltf::GltfScene, util, LoaderError, ResHandle, ResourceLoader, ResourceManager};
+use super::{GltfNode, Material, Mesh, MeshIndices, MeshVertexAttribute, VertexAttributeData};
 
 use tracing::debug;
 
@@ -60,16 +64,23 @@ impl ModelLoader {
         }
     } */
 
-    fn process_node(buffers: &Vec<Vec<u8>>, materials: &Vec<Material>, node: gltf::Node<'_>) -> Vec<Mesh> {
+    fn process_node(ctx: &mut GltfLoadContext, materials: &Vec<ResHandle<Material>>, gnode: gltf::Node<'_>) -> GltfNode {
-        let mut meshes = vec![];
+        let mut node = GltfNode::default();
-        //node.transform()
 
-        if let Some(mesh) = node.mesh() {
+        node.transform = {
-            for prim in mesh.primitives() {
+            let gt = gnode.transform();
-                let reader = prim.reader(|buf| Some(buffers[buf.index()].as_slice()));
+            let (pos, rot, scale) = gt.decomposed();
 
+            Transform::new(Vec3::from(pos), Quat::from_array(rot), Vec3::from(scale))
+        };
+        node.name = gnode.name().map(str::to_string);
+
+        if let Some(mesh) = gnode.mesh() {
             let mut new_mesh = Mesh::default();
 
+            for prim in mesh.primitives() {
+                let reader = prim.reader(|buf| Some(ctx.buffers[buf.index()].as_slice()));
+
                 // read the positions
                 if let Some(pos) = reader.read_positions() {
                     if prim.mode() != gltf::mesh::Mode::Triangles {
@@ -111,18 +122,20 @@ impl ModelLoader {
                 }
 
                 let mat = materials.get(prim.material().index().unwrap()).unwrap();
-                new_mesh.set_material(mat.clone());
+                new_mesh.material = Some(mat.clone());
-
-                meshes.push(new_mesh);
-            }
             }
 
-        for child in node.children() {
+            let handle = ResHandle::with_data("", new_mesh);
-            let mut child_meshes = ModelLoader::process_node(buffers, materials, child);
+            ctx.resource_manager.store_uuid(handle.clone());
-            meshes.append(&mut child_meshes);
+            node.mesh = Some(handle);
         }
 
-        meshes
+        for child in gnode.children() {
+            let cmesh = ModelLoader::process_node(ctx, materials, child);
+            node.children.push(cmesh);
+        }
+        
+        node
     }
 }
 
@@ -147,18 +160,6 @@ impl ResourceLoader for ModelLoader {
         parent_path.pop();
         let parent_path = parent_path.display().to_string();
 
-        /* let (document, buffers, images) = gltf::import(&path)?;
-        let buffers: Vec<Vec<u8>> = buffers.into_iter().map(|b| b.0).collect();
-
-        let scene = document.scenes().next().unwrap();
-
-        let materials: Vec<Material> = document.materials()
-            .map(|mat| Material::from_gltf(resource_manager, &parent_path, mat)).collect();
-
-        let meshes: Vec<Mesh> = scene.nodes()
-            .map(|node| self.process_node(&buffers, &materials, node))
-            .flatten().collect(); */
-
         let gltf = gltf::Gltf::open(path)?;
 
         let mut use_bin = false;
@@ -172,8 +173,7 @@ impl ResourceLoader for ModelLoader {
                     .map_err(ModelLoaderError::UriDecodingError),
             }).collect();
 
-        // TODO: Read in multiple scenes
+        let mut gltf_out = super::Gltf::default();
-        let scene = gltf.scenes().next().unwrap();
 
         let mut context = GltfLoadContext {
             resource_manager,
@@ -183,15 +183,38 @@ impl ResourceLoader for ModelLoader {
             buffers: &buffers,
         };
 
-        let materials: Vec<Material> = gltf.materials()
+        let start_inst = Instant::now();
-            .map(|mat| Material::from_gltf(&mut context, mat)).collect();
+        let materials: Vec<ResHandle<Material>> = gltf.materials()
-
+            .map(|mat| ResHandle::with_data("", Material::from_gltf(&mut context, mat)))
-        let meshes: Vec<Mesh> = scene.nodes()
-            .flat_map(|node| ModelLoader::process_node(&buffers, &materials, node))
             .collect();
-        debug!("Loaded {} meshes, and {} materials from '{}'", meshes.len(), materials.len(), path);
+        let mat_time = Instant::now() - start_inst;
+        debug!("Loaded {} materials in {}s", materials.len(), mat_time.as_secs_f32());
 
-        Ok(Arc::new(ResHandle::with_data(path, Model::new(meshes))))
+        for (idx, scene) in gltf.scenes().enumerate() {
+            let start_inst = Instant::now();
+            let nodes: Vec<GltfNode> = scene.nodes()
+                .map(|node| ModelLoader::process_node(&mut context, &materials, node))
+                .collect();
+            let node_time = Instant::now() - start_inst;
+    
+            debug!("Loaded {} nodes in the scene in {}s", nodes.len(), node_time.as_secs_f32());
+
+            for mesh in nodes.iter().map(|n| &n.mesh) {
+                if let Some(mesh) = mesh {
+                    gltf_out.meshes.push(mesh.clone());
+                }
+            }
+
+            let scene = GltfScene {
+                nodes,
+            };
+            let scene = ResHandle::with_data(&format!("{}:Scene{}", path, idx), scene);
+            gltf_out.scenes.push(scene);
+        }
+
+        gltf_out.materials = materials;
+        
+        Ok(Arc::new(ResHandle::with_data(path, gltf_out)))
     }
 
     #[allow(unused_variables)]
@@ -202,7 +225,7 @@ impl ResourceLoader for ModelLoader {
 
 #[cfg(test)]
 mod tests {
-    use crate::ResourceLoader;
+    use crate::{gltf::Gltf, ResourceLoader};
     use super::*;
 
     fn test_file_path(path: &str) -> String {
@@ -217,16 +240,27 @@ mod tests {
 
         let mut manager = ResourceManager::new();
         let loader = ModelLoader::default();
-        let model = loader.load(&mut manager, &path).unwrap();
+        let gltf = loader.load(&mut manager, &path).unwrap();
-        let model = Arc::downcast::<ResHandle<Model>>(model.as_arc_any()).unwrap();
+        let gltf = Arc::downcast::<ResHandle<Gltf>>(gltf.as_arc_any()).unwrap();
-        let model = model.data_ref();
+        let gltf = gltf.data_ref().unwrap();
-        assert_eq!(model.meshes.len(), 1); // There should only be 1 mesh
+
-        let mesh = &model.meshes[0];
+        assert_eq!(gltf.scenes.len(), 1);
+        let scene = &gltf.scenes[0]
+            .data_ref().unwrap();
+
+        assert_eq!(scene.nodes.len(), 1);
+        let mnode = &scene.nodes[0];
+
+        assert!(mnode.mesh.is_some());
+        assert_eq!(mnode.transform, Transform::from_xyz(0.0, 0.0, 0.0));
+        assert_eq!(mnode.children.len(), 0);
+
+        let mesh = mnode.mesh.as_ref().unwrap();
+        let mesh = mesh.data_ref().unwrap();
         assert!(mesh.position().unwrap().len() > 0);
         assert!(mesh.normals().unwrap().len() > 0);
         assert!(mesh.tex_coords().unwrap().len() > 0);
         assert!(mesh.indices.clone().unwrap().len() > 0);
-        assert!(mesh.material().base_color_texture.is_some());
+        assert!(mesh.material.as_ref().unwrap().data_ref().unwrap().base_color_texture.is_some());
-        let _mesh_mat = mesh.material(); // inner panic if material was not loaded
     }
 }

lyra-resource/src/gltf/material.rs

@@ -1,6 +1,9 @@
 use std::{collections::hash_map::DefaultHasher, hash::{Hash, Hasher}};
 
-use crate::{Texture, ResHandle, util, loader::model::GltfLoadContext};
+use gltf::texture::{MagFilter, MinFilter};
+
+use crate::{util, FilterMode, Image, ResHandle, Texture, TextureSampler, WrappingMode};
+use super::loader::GltfLoadContext;
 
 /// PBR metallic roughness 
 #[derive(Clone, Debug, Default)]
@@ -247,15 +250,33 @@ impl Material {
     fn load_texture(context: &mut GltfLoadContext, texture_info: gltf::texture::Info<'_>) -> ResHandle<Texture> {
         // TODO: texture_info.tex_coord() 
         let tex = texture_info.texture();
+        // TODO: tex.sampler()
         let img = tex.source();
         let src = img.source();
         
         let buf = Material::read_source(context, src).unwrap();
         let buflen = buf.len();
-        let mime_type = infer::get(&buf).expect("Failed to get file type").mime_type();
+        let mime_type = infer::get(&buf).expect("Failed to get image type").mime_type();
 
-        context.resource_manager.load_bytes::<Texture>(&uuid::Uuid::new_v4().to_string(), mime_type,
+        let tex_img = context.resource_manager.load_bytes::<Image>(&uuid::Uuid::new_v4().to_string(), mime_type,
-            buf, 0, buflen).unwrap()
+            buf, 0, buflen).unwrap();
+        
+        let samp = tex.sampler();
+        let samp = TextureSampler {
+            mag_filter: samp.mag_filter().map(FilterMode::from_mag_filter),
+            min_filter: samp.min_filter().map(FilterMode::from_min_filter),
+            mipmap_filter: samp.min_filter().and_then(FilterMode::mipmap_filter),
+            wrap_u: samp.wrap_s().into(),
+            wrap_v: samp.wrap_t().into(),
+            wrap_w: WrappingMode::ClampToEdge,
+        };
+
+        let handler = ResHandle::with_data("", Texture {
+            image: tex_img,
+            sampler: Some(samp),
+        });
+        context.resource_manager.store_uuid(handler.clone());
+        handler
     }
 
     /// Load the Material from a gltf::Material.
@@ -296,3 +317,59 @@ impl Material {
         }
     }
 }
+
+impl From<gltf::texture::MagFilter> for FilterMode {
+    #[inline(always)]
+    fn from(value: gltf::texture::MagFilter) -> Self {
+        match value {
+            gltf::texture::MagFilter::Nearest => Self::Nearest,
+            gltf::texture::MagFilter::Linear => Self::Linear,
+        }
+    }
+}
+
+impl FilterMode {
+    /// Get the MinFilter mode and the mipmap filter mode from gltf MinFilter
+    #[inline(always)]
+    pub fn from_min_filter(minf: MinFilter) -> FilterMode {
+        match minf {
+            MinFilter::Nearest => FilterMode::Nearest,
+            MinFilter::Linear => FilterMode::Linear,
+            MinFilter::NearestMipmapNearest => FilterMode::Nearest,
+            MinFilter::LinearMipmapNearest => FilterMode::Linear,
+            MinFilter::NearestMipmapLinear => FilterMode::Nearest,
+            MinFilter::LinearMipmapLinear => FilterMode::Linear,
+        }
+    }
+
+    #[inline(always)]
+    pub fn from_mag_filter(magf: MagFilter) -> FilterMode {
+        match magf {
+            MagFilter::Nearest => FilterMode::Nearest,
+            MagFilter::Linear => FilterMode::Linear,
+        }
+    }
+
+    #[inline(always)]
+    pub fn mipmap_filter(minf: MinFilter) -> Option<FilterMode> {
+        match minf {
+            MinFilter::Nearest => None,
+            MinFilter::Linear => None,
+            MinFilter::NearestMipmapNearest => Some(FilterMode::Nearest),
+            MinFilter::LinearMipmapNearest => Some(FilterMode::Nearest),
+            MinFilter::NearestMipmapLinear => Some(FilterMode::Linear),
+            MinFilter::LinearMipmapLinear => Some(FilterMode::Linear),
+        }
+    }
+}
+
+impl From<gltf::texture::WrappingMode> for WrappingMode {
+    #[inline(always)]
+    fn from(value: gltf::texture::WrappingMode) -> Self {
+        match value {
+            gltf::texture::WrappingMode::ClampToEdge => Self::ClampToEdge,
+            gltf::texture::WrappingMode::MirroredRepeat => Self::MirroredRepeat,
+            gltf::texture::WrappingMode::Repeat => Self::Repeat,
+        }
+    }
+}

lyra-resource/src/gltf/mesh.rs

@@ -1,7 +1,8 @@
 use std::collections::HashMap;
 
-use crate::Material;
+use crate::{lyra_engine, ResHandle};
-use crate::lyra_engine;
+
+use super::Material;
 
 #[repr(C)]
 #[derive(Clone, Debug, PartialEq)]
@@ -82,23 +83,11 @@ pub enum MeshVertexAttribute {
     Other(String),
 }
 
-#[derive(Clone, lyra_ecs::Component)]
+#[derive(Clone, Default, lyra_ecs::Component)]
 pub struct Mesh {
-    pub uuid: uuid::Uuid,
     pub attributes: HashMap<MeshVertexAttribute, VertexAttributeData>,
     pub indices: Option<MeshIndices>,
-    material: Option<Material>,
+    pub material: Option<ResHandle<Material>>,
-}
-
-impl Default for Mesh {
-    fn default() -> Self {
-        Self {
-            uuid: uuid::Uuid::new_v4(),
-            attributes: Default::default(),
-            indices: Default::default(),
-            material: Default::default()
-        }
-    }
 }
 
 impl Mesh {
@@ -127,26 +116,4 @@ impl Mesh {
         self.attributes.get(&MeshVertexAttribute::TexCoords)
             .map(|p| p.as_vec2())
     }
-
-    pub fn material(&self) -> Material {
-        self.material.clone().expect("This mesh is missing a material!")
-    }
-
-    pub fn set_material(&mut self, val: Material) {
-        self.material = Some(val);
-    }
-}
-
-#[derive(Clone, Default)]
-pub struct Model {
-    pub meshes: Vec<Mesh>,
-    //pub material
-}
-
-impl Model {
-    pub fn new(meshes: Vec<Mesh>) -> Self {
-        Self {
-            meshes,
-        }
-    }
 }

lyra-resource/src/gltf/mod.rs

@@ -0,0 +1,37 @@
+pub mod loader;
+pub use loader::*;
+
+pub mod material;
+use lyra_math::Transform;
+pub use material::*;
+
+pub mod mesh;
+pub use mesh::*;
+
+pub mod scene;
+pub use scene::*;
+
+use crate::ResHandle;
+
+/// A loaded Gltf file
+#[derive(Clone, Default)]
+pub struct Gltf {
+    pub scenes: Vec<ResHandle<GltfScene>>,
+    pub materials: Vec<ResHandle<Material>>,
+    pub meshes: Vec<ResHandle<Mesh>>,
+}
+
+impl Gltf {
+    /// Collects all Gltf meshes and gets their world Transform.
+    pub fn collect_world_meshes(&self) -> Vec<(ResHandle<Mesh>, Transform)> {
+        let mut v = vec![];
+
+        for scene in self.scenes.iter() {
+            let mut tmp = scene.data_ref()
+                .unwrap().collect_world_meshes();
+            v.append(&mut tmp);
+        }
+        
+        v
+    }
+}

lyra-resource/src/gltf/scene.rs

@@ -0,0 +1,55 @@
+use lyra_math::Transform;
+
+use super::Mesh;
+use crate::ResHandle;
+
+/// A Node in the Gltf file
+#[derive(Clone, Default)]
+pub struct GltfNode {
+    pub name: Option<String>,
+    pub mesh: Option<ResHandle<Mesh>>,
+    pub transform: Transform,
+    pub children: Vec<GltfNode>,
+}
+
+/// A Scene in a Gltf file
+#[derive(Clone)]
+pub struct GltfScene {
+    pub nodes: Vec<GltfNode>,
+}
+
+impl GltfScene {
+    fn collect_node(&self, parent_node: &GltfNode, node: &GltfNode) -> Vec<(ResHandle<Mesh>, Transform)> {
+        let mut v = vec![];
+
+        if let Some(mesh) = &node.mesh {
+            v.push((mesh.clone(), parent_node.transform + node.transform));
+        }
+
+        for child in node.children.iter() {
+            let mut tmp = self.collect_node(node, child);
+            v.append(&mut tmp);
+        }
+
+        v
+    }
+
+    /// Collects all Gltf meshes and gets their world Transform.
+    pub fn collect_world_meshes(&self) -> Vec<(ResHandle<Mesh>, Transform)> {
+        let mut v = vec![];
+
+        // process the root nodes in the scene
+        for parent_node in self.nodes.iter() {
+            if let Some(mesh) = &parent_node.mesh {
+                v.push((mesh.clone(), parent_node.transform));
+            }
+
+            for child in parent_node.children.iter() {
+                let mut tmp = self.collect_node(parent_node, child);
+                v.append(&mut tmp);
+            }
+        }
+        
+        v
+    }
+}

lyra-resource/src/lib.rs

@@ -10,11 +10,7 @@ pub use texture::*;
 pub mod loader;
 pub use loader::*;
 
-pub mod model;
+pub mod gltf;
-pub use model::*;
-
-pub mod material;
-pub use material::*;
 
 pub mod world_ext;
 pub use world_ext::*;

lyra-resource/src/loader/image.rs

@@ -1,8 +1,9 @@
 use std::{fs::File, sync::Arc, io::Read};
 
 use image::ImageError;
+use tracing::{debug, trace};
 
-use crate::{resource_manager::ResourceStorage, texture::Texture, resource::ResHandle, ResourceManager};
+use crate::{resource::ResHandle, resource_manager::ResourceStorage, Image, ResourceManager};
 
 use super::{LoaderError, ResourceLoader};
 
@@ -12,7 +13,7 @@ impl From<ImageError> for LoaderError {
     }
 }
 
-/// A struct that implements the `ResourceLoader` trait used for loading textures.
+/// A struct that implements the `ResourceLoader` trait used for loading images.
 #[derive(Default)]
 pub struct ImageLoader;
 
@@ -59,24 +60,24 @@ impl ResourceLoader for ImageLoader {
                 ImageError::IoError(e) => LoaderError::IoError(e),
                 _ => LoaderError::DecodingError(e.into()),
             })?;
-        let texture = Texture {
+        let image = Image::from(image);
-            image,
+        let res = ResHandle::with_data(path, image);
-        };
-        let res = ResHandle::with_data(path, texture);
 
         Ok(Arc::new(res))
     }
 
     fn load_bytes(&self, _resource_manager: &mut ResourceManager, bytes: Vec<u8>, offset: usize, length: usize) -> Result<Arc<dyn ResourceStorage>, LoaderError> {
+        trace!("Loading {} bytes as an image", length);
+        
         let image = image::load_from_memory(&bytes[offset..(length-offset)])
             .map_err(|e| match e {
                 ImageError::IoError(e) => LoaderError::IoError(e),
                 _ => LoaderError::DecodingError(e.into()),
             })?;
-        let texture = Texture {
+        let image = Image::from(image);
-            image,
+        let res = ResHandle::with_data(&uuid::Uuid::new_v4().to_string(), image);
-        };
+        
-        let res = ResHandle::with_data(&uuid::Uuid::new_v4().to_string(), texture);
+        debug!("Finished loading image of {} bytes", length);
 
         Ok(Arc::new(res))
     }

lyra-resource/src/loader/mod.rs

@@ -1,5 +1,4 @@
 pub mod image;
-pub mod model;
 
 use std::{io, sync::Arc, path::Path, ffi::OsStr};
 

lyra-resource/src/resource.rs

@@ -1,5 +1,7 @@
 use std::{any::Any, sync::{Arc, RwLock}};
 
+use lyra_ecs::Component;
+use crate::lyra_engine;
 use uuid::Uuid;
 
 use crate::ResourceStorage;
@@ -38,7 +40,8 @@ pub struct Resource<T> {
 /// This struct has an inner [`RwLock`] to the resource data, so most methods may be blocking.
 /// However, the only times it will be blocking is if another thread is reloading the resource
 /// and has a write lock on the data. This means that most of the time, it is not blocking.
-pub struct ResHandle<T> {
+#[derive(Component)]
+pub struct ResHandle<T: 'static> {
     pub(crate) data: Arc<RwLock<Resource<T>>>,
 }
 
@@ -103,18 +106,7 @@ impl<T> ResHandle<T> {
     }
 
     /// Get a reference to the data in the resource
-    ///
+    pub fn data_ref<'a>(&'a self) -> Option<ResourceDataRef<'a, T>> {
-    /// # Panics
-    /// Panics if the resource was not loaded yet.
-    pub fn data_ref<'a>(&'a self) -> ResourceDataRef<'a, T> {
-        let d = self.data.read().expect("Resource mutex was poisoned!");
-        ResourceDataRef {
-            guard: d
-        }
-    }
-
-    /// Attempt to get a borrow to the resource data. Returns `None` if the resource is not loaded.
-    pub fn try_data_ref<'a>(&'a self) -> Option<ResourceDataRef<'a, T>> {
         if self.is_loaded() {
             let d = self.data.read().expect("Resource mutex was poisoned!");
             Some(ResourceDataRef {

lyra-resource/src/resource_manager.rs

@@ -6,7 +6,7 @@ use notify_debouncer_full::{DebouncedEvent, FileIdMap};
 use thiserror::Error;
 use uuid::Uuid;
 
-use crate::{loader::{image::ImageLoader, model::ModelLoader, LoaderError, ResourceLoader}, resource::ResHandle, ResourceState};
+use crate::{gltf::ModelLoader, loader::{image::ImageLoader, LoaderError, ResourceLoader}, resource::ResHandle, ResourceState};
 
 /// A trait for type erased storage of a resource.
 /// Implemented for [`ResHandle<T>`]
@@ -56,6 +56,7 @@ pub struct ResourceWatcher {
 
 pub struct ResourceManager {
     resources: HashMap<String, Arc<dyn ResourceStorage>>,
+    uuid_resources: HashMap<Uuid, Arc<dyn ResourceStorage>>,
     loaders: Vec<Arc<dyn ResourceLoader>>,
     watchers: HashMap<String, ResourceWatcher>,
 }
@@ -70,6 +71,7 @@ impl ResourceManager {
     pub fn new() -> Self {
         Self {
             resources: HashMap::new(),
+            uuid_resources: HashMap::new(),
             loaders: vec![ Arc::new(ImageLoader), Arc::new(ModelLoader) ],
             watchers: HashMap::new(),
         }
@@ -148,6 +150,29 @@ impl ResourceManager {
         }
     }
 
+    /// Store a resource using its uuid.
+    /// 
+    /// The resource cannot be requested with [`ResourceManager::request`], it can only be 
+    /// retrieved with [`ResourceManager::request_uuid`].
+    pub fn store_uuid<T: Send + Sync + 'static>(&mut self, res: ResHandle<T>) {
+        self.uuid_resources.insert(res.uuid(), Arc::new(res));
+    }
+
+    /// Request a resource via its uuid.
+    /// 
+    /// Returns `None` if the resource was not found. The resource must of had been
+    /// stored with [`ResourceManager::request`] to return `Some`.
+    pub fn request_uuid<T: Send + Sync + 'static>(&mut self, uuid: &Uuid) -> Option<ResHandle<T>> {
+        match self.uuid_resources.get(uuid) {
+            Some(res) => {
+                let res = res.clone().as_arc_any();
+                let res: Arc<ResHandle<T>> = res.downcast::<ResHandle<T>>().expect("Failure to downcast resource");
+                Some(ResHandle::<T>::clone(&res))
+            },
+            None => None,
+        }
+    }
+
     /// Store bytes in the manager. If there is already an entry with the same identifier it will be updated.
     /// 
     /// Panics: If there is already an entry with the same `ident`, and the entry is not bytes, this function will panic.
@@ -304,7 +329,7 @@ mod tests {
         let mut man = ResourceManager::new();
         let res = man.request::<Texture>(&get_image("squiggles.png")).unwrap();
         assert_eq!(res.state(), ResourceState::Ready);
-        let img = res.try_data_ref();
+        let img = res.data_ref();
         img.unwrap();
     }
 
@@ -340,7 +365,7 @@ mod tests {
         let mut man = ResourceManager::new();
         let res = man.request::<Texture>(&get_image("squiggles.png")).unwrap();
         assert_eq!(res.state(), ResourceState::Ready);
-        let img = res.try_data_ref();
+        let img = res.data_ref();
         img.unwrap();
 
         println!("Path = {}", res.path());
@@ -360,7 +385,7 @@ mod tests {
         let mut man = ResourceManager::new();
         let res = man.request::<Texture>(&image_path).unwrap();
         assert_eq!(res.state(), ResourceState::Ready);
-        let img = res.try_data_ref();
+        let img = res.data_ref();
         img.unwrap();
 
         let recv = man.watch(&image_path, false).unwrap();

lyra-resource/src/texture.rs

@@ -1,10 +1,73 @@
+use std::ops::{Deref, DerefMut};
+
+//pub use gltf::texture::{MagFilter, MinFilter, WrappingMode};
 use image::DynamicImage;
 
+use crate::ResHandle;
+
+/// The filter mode of the sampler.
+/// 
+/// This is used for minification, magnification, and mipmap filters
+#[derive(Clone, Copy, PartialEq, Eq)]
+pub enum FilterMode {
+    Nearest,
+    Linear,
+}
+
+/// The wrapping mode of the Texture coordinates
+#[derive(Clone, Copy, PartialEq, Eq)]
+pub enum WrappingMode {
+    ClampToEdge,
+    MirroredRepeat,
+    Repeat,
+}
+
+/// The descriptor of the sampler for a Texture.
+#[derive(Clone)]
+pub struct TextureSampler {
+    pub mag_filter: Option<FilterMode>,
+    pub min_filter: Option<FilterMode>,
+    pub mipmap_filter: Option<FilterMode>,
+    pub wrap_u: WrappingMode,
+    pub wrap_v: WrappingMode,
+    pub wrap_w: WrappingMode,
+}
+
+#[derive(Clone)]
+pub struct Image(DynamicImage);
+
+impl Deref for Image {
+    type Target = DynamicImage;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl DerefMut for Image {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+
+impl From<DynamicImage> for Image {
+    fn from(value: DynamicImage) -> Self {
+        Self(value)
+    }
+}
+
 #[derive(Clone)]
 pub struct Texture {
-    pub image: DynamicImage,
+    pub image: ResHandle<Image>,
+    pub sampler: Option<TextureSampler>,
 }
 
 impl Texture {
-    
+    /// Create a texture from an image.
+    pub fn from_image(image: ResHandle<Image>) -> Self {
+        Self {
+            image,
+            sampler: None,
+        }
+    }
 }

lyra-scene/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "lyra-scene"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+lyra-ecs = { path = "../lyra-ecs", features = [ "math" ] }
+lyra-math = { path = "../lyra-math" }

lyra-scene/src/lib.rs

@@ -0,0 +1,316 @@
+use std::{collections::VecDeque, ops::{Deref, DerefMut}};
+
+use lyra_ecs::{query::Entities, relation::ChildOf, Bundle, Component, Entity, World};
+
+// So we can use lyra_ecs::Component derive macro
+pub(crate) mod lyra_engine {
+    pub(crate) mod ecs {
+        pub use lyra_ecs::*;
+    }
+}
+
+mod node;
+use lyra_math::{Transform, Vec3};
+pub use node::*;
+
+/// A flag spawned on all scene node entities
+#[derive(Component)]
+pub struct SceneNodeFlag;
+
+/// A flag spawned on only the scene root node
+#[derive(Component)]
+pub struct SceneNodeRoot;
+
+enum MutCow<'a, T> {
+    Mut(&'a mut T),
+    Owned(T),
+}
+
+impl<'a, T> Deref for MutCow<'a, T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        match self {
+            MutCow::Mut(t) => t,
+            MutCow::Owned(t) => t,
+        }
+    }
+}
+
+impl<'a, T> DerefMut for MutCow<'a, T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        match self {
+            MutCow::Mut(t) => t,
+            MutCow::Owned(t) => t,
+        }
+    }
+}
+
+/// A SceneGraph is a Graph of nodes that represents the hierarchy of a scene.
+/// 
+/// This SceneGraph is special in the sense that it is literally just an ECS world with methods
+/// implemented for it that make it easier to use for a SceneGraph.
+//#[derive(Default)]
+pub struct SceneGraph<'a>  {
+    pub(crate) world: MutCow<'a, World>,
+    root_node: SceneNode,
+}
+
+impl<'a> SceneGraph<'a> {
+    /// Create a new SceneGraph with its own ECS World.
+    pub fn new() -> Self {
+        let mut world = World::new();
+        
+        let e = world.spawn((Transform::from_translation(Vec3::new(0.0, 0.0, 0.0)), SceneNodeRoot));
+        let root = SceneNode::new(None, e);
+
+        Self {
+            world: MutCow::Owned(world),
+            root_node: root
+        }
+    }
+
+    /// Retrieve a SceneGraph from an ECS World.
+    /// 
+    /// Returns `None` if the `root_entity` was not created from a `SceneGraph` that was later
+    /// inserted into another world with [`SceneGraph::into_world`].
+    pub fn from_world(world: &'a mut World, root_entity: Entity) -> Option<Self> {
+        if world.view_one::<(&SceneNodeRoot, &Transform)>(root_entity).get().is_none() {
+            None
+        } else {
+            Some(Self {
+                world: MutCow::Mut(world),
+                root_node: SceneNode::new(None, root_entity),
+            })
+        }
+    }
+
+    /// Create a new SceneGraph inside an existing ECS World.
+    pub fn new_from_world(world: &'a mut World) -> Self {
+        let root_en = world.spawn((Transform::from_translation(Vec3::new(0.0, 0.0, 0.0)), SceneNodeRoot));
+        let root = SceneNode::new(None, root_en);
+
+        Self {
+            world: MutCow::Mut(world),
+            root_node: root,
+        }
+    }
+
+    /// Consume the SceneGraph, inserting its internal world into the provided world.
+    /// 
+    /// The `into` World will contain all nodes of the SceneGraph. You could iterate through the
+    /// SceneGraph manually if you'd like. The root entity has a [`SceneNodeRoot`] flag component,
+    /// and a Transform component. The children nodes have a [`SceneNodeFlag`] component and a 
+    /// Transform component. The transforms of the children will be local, you must find its world
+    /// transform by traversing up the hierarchy of the scene manually with the `ChildOf` relation.
+    /// 
+    /// Returns: the Entity of the root node in the provided world.
+    pub fn into_world(mut self, into: &mut World) -> Entity {
+        // first insert the root entity into the World.
+        let v = self.world.view_one::<&Transform>(self.root_node.entity());
+        let pos = *v.get().unwrap();
+        let new_root = into.spawn((pos, SceneNodeRoot));
+
+        // now process the children of the root node.
+        Self::traverse_inserting_into(&mut self.world, self.root_node.entity(), new_root, into);
+        new_root
+    }
+
+    /// Recursively traverse the `from` world, starting at `node_en`, inserting the
+    /// children entity into the world.
+    /// 
+    /// Parameters:
+    /// * `scene_world` - The world that the SceneGraph exists in
+    /// * `scene_en` - The entity of the parent entity inside of the `scene_world`.
+    /// * `parent_en` - The entity of the parent entity inside of the `into` world.
+    /// * `into` - The world to insert the SceneGraph world into.
+    fn traverse_inserting_into(scene_world: &mut World, scene_en: Entity, parent_en: Entity, into: &mut World) {
+        let v = scene_world.view::<(Entities, &Transform)>()
+            .relates_to::<ChildOf>(scene_en);
+
+        // unfortunately, the borrow checker exists, and wasn't happy that `scene_world` was
+        // immutably borrowed with the view (v), and being mutably borrowed in the
+        // recursive call.
+        let mut child_entities = VecDeque::new();
+
+        for ((child_scene_en, pos), _rel) in v.iter() {
+            let into_en = into.spawn((*pos, SceneNodeFlag));
+            into.add_relation(into_en, ChildOf, parent_en);
+
+            child_entities.push_back((child_scene_en, into_en));
+        }
+
+        while let Some((child_scene_en, into_en)) = child_entities.pop_front() {
+            Self::traverse_inserting_into(scene_world, child_scene_en, into_en, into);
+        }
+    }
+
+    /// Adds a node to the root node of the SceneGraph.
+    /// 
+    /// The spawned entity will have a `ChildOf` relation targeting the root node, the
+    /// `SceneNodeFlag` component is also added to the entity.
+    pub fn add_node<B: Bundle>(&mut self, local_transform: Transform, bundle: B) -> SceneNode {
+        let node = self.root_node.clone();
+        self.add_node_under(&node, local_transform, bundle)
+    }
+
+    /// Add a node under a parent node.
+    /// 
+    /// The spawned entity will have a `ChildOf` relation targeting the provided parent node,
+    /// the `SceneNodeFlag` component is also added to the entity.
+    pub fn add_node_under<B: Bundle>(&mut self, parent: &SceneNode, local_transform: Transform, bundle: B) -> SceneNode {
+        world_add_child_node(&mut self.world, parent, local_transform, bundle)
+    }
+
+    pub fn add_empty_node_under(&mut self, parent: &SceneNode, local_transform: Transform) -> SceneNode {
+        let e = self.world.spawn((SceneNodeFlag, local_transform));
+        self.world.add_relation(e, ChildOf, parent.entity());
+
+        SceneNode::new(Some(parent.entity()), e)
+    }
+
+    /// Traverses down the SceneGraph, calling `callback` with each SceneNode and its world transform.
+    /// 
+    /// The traversal does not include the root scene node.
+    pub fn traverse_down<F>(&self, mut callback: F)
+    where
+        F: FnMut(&SceneNode, Transform),
+    {
+        self.traverse_down_from(self.root_node.clone(), &mut callback);
+    }
+
+    /// Recursively Traverses down the SceneGraph from a starting node, calling `callback` with each
+    /// SceneNode and its world transform.
+    fn traverse_down_from<F>(&self, start: SceneNode, callback: &mut F)
+    where
+        F: FnMut(&SceneNode, Transform),
+    {
+        let v = self.world.view::<(Entities, &Transform)>()
+            .relates_to::<ChildOf>(start.entity());
+
+        for ((e, _), _rel) in v.iter() {
+            let node = SceneNode::new(Some(start.entity()), e);
+            let world_pos = node.world_transform(self);
+            callback(&node, world_pos);
+
+            self.traverse_down_from(node, callback);
+        }
+    }
+
+    pub fn root_node(&self) -> SceneNode {
+        self.root_node.clone()
+    }
+}
+
+/// Add a node under a parent node.
+/// 
+/// The spawned entity will have a `ChildOf` relation targeting the provided parent node,
+/// the `SceneNodeFlag` component is also added to the entity.
+pub(crate) fn world_add_child_node<B: Bundle>(world: &mut World, parent: &SceneNode, local_transform: Transform, bundle: B) -> SceneNode {
+    let e = world.spawn(bundle);
+    world.insert(e, (SceneNodeFlag, local_transform));
+    world.add_relation(e, ChildOf, parent.entity());
+
+    SceneNode::new(Some(parent.entity()), e)
+}
+
+#[cfg(test)]
+pub mod tests {
+    use lyra_ecs::{query::Entities, relation::ChildOf, Component, World};
+    use lyra_math::{Transform, Vec3};
+
+    use crate::{lyra_engine, SceneGraph, SceneNodeRoot};
+
+    #[derive(Component)]
+    pub struct FakeMesh;
+
+    #[test]
+    fn single_node_hierarchy() {
+        let mut scene = SceneGraph::new();
+
+        let a = scene.add_node(Transform::from_translation(Vec3::new(10.0, 10.0, 10.0)), FakeMesh);
+        assert!(a.parent(&scene).unwrap() == scene.root_node);
+    }
+
+    #[test]
+    fn double_node_hierarchy() {
+        let mut scene = SceneGraph::new();
+
+        let a = scene.add_node(Transform::from_translation(Vec3::new(10.0, 10.0, 10.0)), FakeMesh);
+        assert!(a.parent(&scene).unwrap() == scene.root_node);
+
+        let b = a.add_node(&mut scene, Transform::from_translation(Vec3::new(50.0, 50.0, 50.0)), FakeMesh);
+        assert!(b.parent(&scene).unwrap() == a);
+    }
+
+    #[test]
+    fn traverse_down() {
+        let v2s = vec![Vec3::new(10.0, 10.0, 10.0), Vec3::new(50.0, 50.0, 50.0)];
+
+        let mut scene = SceneGraph::new();
+
+        let a = scene.add_node(Transform::from_translation(v2s[0]), FakeMesh);
+        assert!(a.parent(&scene).unwrap() == scene.root_node);
+        let b = a.add_node(&mut scene, Transform::from_translation(v2s[1]), FakeMesh);
+        assert!(b.parent(&scene).unwrap() == a);
+
+        let mut idx = 0;
+        scene.traverse_down(|_e, pos| {
+            if idx == 0 {
+                assert_eq!(pos, Transform::from_translation(v2s[idx]));
+            } else if idx == 1 {
+                let t = v2s.iter().sum();
+                assert_eq!(pos, Transform::from_translation(t));
+            }
+
+            idx += 1;
+        });
+    }
+
+    /* #[test]
+    fn inserting_and_from_world() {
+        let v2s = vec![Vec3::new(10.0, 10.0, 10.0), Vec3::new(50.0, 50.0, 50.0)];
+
+        let mut scene = SceneGraph::new();
+
+        let a = scene.add_node(Transform::from_translation(v2s[0]), FakeMesh);
+        assert!(a.parent(&scene).unwrap() == scene.root_node);
+        let b = a.add_node(&mut scene, Transform::from_translation(v2s[1]), FakeMesh);
+        assert!(b.parent(&scene).unwrap() == a);
+
+        let mut other_world = World::new();
+        let root = scene.into_world(&mut other_world);
+        
+        // check all of the entities inside of the World
+        let (root_pos, _) = other_world.view_one::<(&Transform, &SceneNodeRoot)>(root).get().unwrap();
+        assert_eq!(*root_pos, Transform::from_xyz(0.0, 0.0, 0.0));
+
+        let ((child_en, child_pos), _)  = other_world.view::<(Entities, &Transform)>()
+            .relates_to::<ChildOf>(root).iter().next().unwrap();
+        assert_eq!(*child_pos, Transform::from_translation(v2s[0]));
+
+        let ((_, childchild_pos), _)  = other_world.view::<(Entities, &Transform)>()
+            .relates_to::<ChildOf>(child_en).iter().next().unwrap();
+        assert_eq!(*childchild_pos, Transform::from_translation(v2s[1]));
+        
+        drop(root_pos);
+        drop(child_pos);
+        drop(childchild_pos);
+
+        // Now get the SceneGraph inside the World and use the nice utility tools to traverse it.
+        let scene = SceneGraph::from_world(&mut other_world, root)
+            .expect("Failed to get SceneGraph from World!");
+
+        let mut idx = 0;
+        scene.traverse_down(|_e, pos| {
+            if idx == 0 {
+                assert_eq!(pos, Transform::from_translation(v2s[idx]));
+            } else if idx == 1 {
+                let t = v2s.iter().sum();
+                assert_eq!(pos, Transform::from_translation(t));
+            }
+
+            idx += 1;
+        });
+    } */
+}

lyra-scene/src/node.rs

@@ -0,0 +1,101 @@
+use lyra_ecs::{query::Entities, relation::{ChildOf, RelationOriginComponent}, Bundle, Entity};
+use lyra_math::Transform;
+
+use crate::SceneGraph;
+
+#[derive(Clone, PartialEq, Eq)]
+pub struct SceneNode {
+    //world: WorldLock,
+    parent: Option<Entity>,
+    entity: Entity
+}
+
+impl SceneNode {
+    pub fn new(parent: Option<Entity>, entity: Entity) -> Self {
+        Self {
+            parent,
+            entity,
+        }
+    }
+
+    /// If this node has a parent, retrieves the parent node from the SceneGraph.
+    pub fn parent(&self, graph: &SceneGraph) -> Option<SceneNode> {
+        if let Some(parent) = self.parent {
+            let v = graph.world.view_one::<&RelationOriginComponent<ChildOf>>(parent);
+            
+            let p_parent = if let Some(pp) = v.get() {
+                Some(pp.target())
+            } else { None };
+
+            Some(SceneNode::new(p_parent, parent))
+        } else {
+            None
+        }
+    }
+
+    pub fn parent_entity(&self) -> Option<Entity> {
+        self.parent
+    }
+
+    pub fn children(&self, graph: &SceneGraph) -> Vec<SceneNode> {
+        let v = graph.world.view::<Entities>()
+            .relates_to::<ChildOf>(self.entity);
+
+        v.into_iter().map(|(e, _)| SceneNode::new(Some(self.entity), e)).collect()
+    }
+
+    pub fn entity(&self) -> Entity {
+        self.entity
+    }
+
+    /// Add a child node to this node.
+    /// 
+    /// The spawned entity backing the scene node will have a `ChildOf` relation targeting
+    /// the provided parent node, the `SceneNodeFlag` component is also added to the entity.
+    pub fn add_node<B: Bundle>(&self, graph: &mut SceneGraph, local_transform: Transform, bundle: B) -> SceneNode {
+        graph.add_node_under(self, local_transform, bundle)
+    }
+
+    pub fn local_transform(&self, graph: &SceneGraph) -> Transform {
+        let v = graph.world.view_one::<&Transform>(self.entity);
+
+        let t = v.get().expect("Somehow the SceneNode is missing its Transform!");
+        t.clone()
+    }
+
+    /// Retrieves the world transform of the Node.
+    /// 
+    /// This traverses up the SceneGraph from this node.
+    pub fn world_transform(&self, graph: &SceneGraph) -> Transform {
+        match self.parent(graph) {
+            Some(parent) => {
+                let pt = parent.world_transform(graph);
+                pt + self.local_transform(graph)
+            },
+            None => {
+                self.local_transform(graph)
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use lyra_math::{Transform, Vec3};
+    
+    use crate::{tests::FakeMesh, SceneGraph};
+
+    #[test]
+    fn node_world_transform() {
+        let mut scene = SceneGraph::new();
+
+        let a = scene.add_node(Transform::from_translation(Vec3::new(10.0, 10.0, 10.0)), FakeMesh);
+        assert!(a.parent(&scene).unwrap() == scene.root_node);
+        
+        let b = a.add_node(&mut scene, Transform::from_translation(Vec3::new(50.0, 50.0, 50.0)), FakeMesh);
+        assert!(b.parent(&scene).unwrap() == a);
+
+        let wrld_tran = b.world_transform(&scene);
+        assert_eq!(wrld_tran, Transform::from_translation(Vec3::new(60.0, 60.0, 60.0)));
+    }
+}