scene: improve docs and some code cleanup

lyra-scene/src/lib.rs

@@ -22,7 +22,7 @@ pub struct SceneNodeFlag;
 #[derive(Component)]
 pub struct SceneNodeRoot;
 
-/// A SceneGraph is a Graph of nodes that represents the hierarchy of a scene.
+/// 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.

lyra-scene/src/node.rs

@@ -2,9 +2,9 @@ use lyra_ecs::{query::Entities, relation::{ChildOf, RelationOriginComponent}, Bu
 
 use crate::SceneGraph;
 
+/// A node inside of the Scene
 #[derive(Clone, PartialEq, Eq)]
 pub struct SceneNode {
-    //world: WorldLock,
     parent: Option<Entity>,
     entity: Entity
 }
@@ -54,28 +54,6 @@ impl SceneNode {
     pub fn add_node<B: Bundle>(&self, graph: &mut SceneGraph, bundle: B) -> SceneNode {
         graph.add_node_under(self, 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)]

lyra-scene/src/world_transform.rs

@@ -4,6 +4,13 @@ use lyra_ecs::{query::{filter::{Has, Not}, Entities, View}, relation::{ChildOf,
 use lyra_math::Transform;
 use crate::lyra_engine;
 
+/// The world transform of an entity.
+/// 
+/// A Transform represents the relative position of the entity to its parent entity, while
+/// a world transform is the position relative to the World. When wanting to move an entity,
+/// you should use its [`Transform`]. You cannot mutate [`WorldTransform`] as its managed completey
+/// by the [`system_update_world_transforms`] system. For the WorldTransform to work properly, you
+/// must have both a [`Transform`] and [`WorldTransform`] on the entities in the scene.
 #[derive(Debug, Copy, Clone, PartialEq, Default, Component)]
 pub struct WorldTransform(pub(crate) Transform);
 
@@ -18,14 +25,11 @@ impl Deref for WorldTransform {
 /// A system that updates the [`WorldTransform`]'s for entities and their children.
 /// 
 /// For entities without parents, this will update world transform to match local transform.
-/// For any children entities, their [`GlobalTransform`]s will be updated to reflect the changes
+/// For any children entities, their [`WorldTransform`]s will be updated to reflect the changes
 /// of its parent entity.
 pub fn system_update_world_transforms(world: &World, view: View<(Entities, &mut WorldTransform, &Transform, Not<Has<RelationOriginComponent<ChildOf>>>)>) -> anyhow::Result<()> {    
-
     for (en, mut world_tran, tran, _) in view.into_iter() {
         world_tran.0 = *tran;
-        println!("Found entity {:?} at {:?}", en, world_tran.translation);
-
         recurse_update_trans(world, &world_tran, en);
     }
 
@@ -47,8 +51,7 @@ fn recurse_update_trans(world: &World, parent_transform: &WorldTransform, entity
         next_entities.push((en, world_tran.0.clone()));
     }
 
-    next_entities.reverse();
-    while let Some((en, pos)) = next_entities.pop() {
+    for (en, pos) in next_entities.into_iter() {
         recurse_update_trans(world, &WorldTransform(pos), en);
     }
 }