From fd2b1683cc7c575ac0cfad29fef8072517ac19f4 Mon Sep 17 00:00:00 2001
From: SeanOMik <seanomik@gmail.com>
Date: Mon, 4 Mar 2024 18:31:25 -0500
Subject: [PATCH] resource: load multiple gltf scenes

---
 lyra-resource/src/gltf/loader.rs | 49 ++++++++++++++++++--------------
 lyra-resource/src/gltf/mod.rs    |  9 +++++-
 lyra-resource/src/gltf/scene.rs  |  3 +-
 3 files changed, 38 insertions(+), 23 deletions(-)

diff --git a/lyra-resource/src/gltf/loader.rs b/lyra-resource/src/gltf/loader.rs
index 2b26645..20ff5ad 100644
--- a/lyra-resource/src/gltf/loader.rs
+++ b/lyra-resource/src/gltf/loader.rs
@@ -173,8 +173,7 @@ impl ResourceLoader for ModelLoader {
                     .map_err(ModelLoaderError::UriDecodingError),
             }).collect();
 
-        // TODO: Read in multiple scenes
-        let scene = gltf.scenes().next().unwrap();
+        let mut gltf_out = super::Gltf::default();
 
         let mut context = GltfLoadContext {
             resource_manager,
@@ -189,22 +188,27 @@ impl ResourceLoader for ModelLoader {
             .map(|mat| Material::from_gltf(&mut context, mat))
             .collect();
         let mat_time = Instant::now() - start_inst;
+        debug!("Loaded {} materials in {}s", materials.len(), mat_time.as_secs_f32());
 
-        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;
+        for scene in gltf.scenes() {
+            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());
 
-        debug!("Loaded {} nodes (in {}s), and {} materials (in {}s) from '{}'", nodes.len(),
-            node_time.as_secs_f32(), materials.len(), mat_time.as_secs_f32(), path);
-
-        let scene = GltfScene {
-            nodes,
-            materials,
-        };
-
-        Ok(Arc::new(ResHandle::with_data(path, scene)))
+            /* debug!("Loaded {} nodes (in {}s), and {} materials (in {}s) from '{}'", nodes.len(),
+                node_time.as_secs_f32(), materials.len(), mat_time.as_secs_f32(), path); */
+    
+            let scene = GltfScene {
+                nodes,
+            };
+            gltf_out.scenes.push(scene);
+        }
+        
+        Ok(Arc::new(ResHandle::with_data(path, gltf_out)))
     }
 
     #[allow(unused_variables)]
@@ -215,7 +219,7 @@ 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 {
@@ -230,13 +234,16 @@ mod tests {
 
         let mut manager = ResourceManager::new();
         let loader = ModelLoader::default();
-        let scene = loader.load(&mut manager, &path).unwrap();
-        let scene = Arc::downcast::<ResHandle<GltfScene>>(scene.as_arc_any()).unwrap();
-        let scene = scene.data_ref();
+        let gltf = loader.load(&mut manager, &path).unwrap();
+        let gltf = Arc::downcast::<ResHandle<Gltf>>(gltf.as_arc_any()).unwrap();
+        let gltf = gltf.data_ref();
+
+        assert_eq!(gltf.scenes.len(), 1);
+        let scene = &gltf.scenes[0];
 
         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);
diff --git a/lyra-resource/src/gltf/mod.rs b/lyra-resource/src/gltf/mod.rs
index 18772fc..0f7c8ac 100644
--- a/lyra-resource/src/gltf/mod.rs
+++ b/lyra-resource/src/gltf/mod.rs
@@ -8,4 +8,11 @@ pub mod mesh;
 pub use mesh::*;
 
 pub mod scene;
-pub use scene::*;
\ No newline at end of file
+pub use scene::*;
+
+/// A loaded Gltf file
+#[derive(Clone, Default)]
+pub struct Gltf {
+    pub scenes: Vec<GltfScene>,
+    pub materials: Vec<Material>,
+}
\ No newline at end of file
diff --git a/lyra-resource/src/gltf/scene.rs b/lyra-resource/src/gltf/scene.rs
index cd64df7..8b14456 100644
--- a/lyra-resource/src/gltf/scene.rs
+++ b/lyra-resource/src/gltf/scene.rs
@@ -6,6 +6,7 @@ use lyra_math::Transform;
 use super::{Material, Mesh};
 use crate::{lyra_engine, ResHandle};
 
+/// A Node in the Gltf file
 #[derive(Clone, Default)]
 pub struct GltfNode {
     pub name: Option<String>,
@@ -14,8 +15,8 @@ pub struct GltfNode {
     pub children: Vec<GltfNode>,
 }
 
+/// A Scene in a Gltf file
 #[derive(Clone)]
 pub struct GltfScene {
     pub nodes: Vec<GltfNode>,
-    pub materials: Vec<Material>,
 }
\ No newline at end of file