From b92081d06ebea3ca25b32b974ef18b42e4f51e20 Mon Sep 17 00:00:00 2001
From: Jan Hohenheim <jan@hohenheim.ch>
Date: Tue, 23 Jul 2024 23:42:25 +0200
Subject: [PATCH] fix(Blenvy:Bevy): Fix direct file access for gltf preload on
 Wasm (#199)

* Fix direct file access
* Fix dropped handles
* Remove debug messages
* Minor refactoring
* Fix access
---
 crates/blenvy/src/blueprints/mod.rs           | 13 ++--
 .../src/blueprints/spawn_from_blueprints.rs   | 63 +++++++++++++++++--
 2 files changed, 64 insertions(+), 12 deletions(-)

diff --git a/crates/blenvy/src/blueprints/mod.rs b/crates/blenvy/src/blueprints/mod.rs
index 4a1c2d2..2d1ade6 100644
--- a/crates/blenvy/src/blueprints/mod.rs
+++ b/crates/blenvy/src/blueprints/mod.rs
@@ -49,16 +49,14 @@ impl Default for BluePrintBundle {
 
 #[derive(Debug, Clone)]
 /// Plugin for gltf blueprints
-pub struct BlueprintsPlugin {
-}
+pub struct BlueprintsPlugin {}
 
 impl Default for BlueprintsPlugin {
     fn default() -> Self {
-        Self { }
+        Self {}
     }
 }
 
-
 fn hot_reload(watching_for_changes: Res<WatchingForChanges>) -> bool {
     // println!("hot reload ? {}", watching_for_changes.0);
     watching_for_changes.0
@@ -110,6 +108,8 @@ impl Plugin for BlueprintsPlugin {
             .register_type::<Vec<String>>()
             .register_type::<BlueprintAssets>()
             .register_type::<HashMap<String, Vec<String>>>()
+            .init_asset::<RawGltfAsset>()
+            .init_asset_loader::<RawGltfAssetLoader>()
             .configure_sets(
                 Update,
                 (GltfBlueprintsSet::Spawn, GltfBlueprintsSet::AfterSpawn)
@@ -119,6 +119,7 @@ impl Plugin for BlueprintsPlugin {
             .add_systems(
                 Update,
                 (
+                    load_raw_gltf,
                     blueprints_prepare_spawn,
                     blueprints_check_assets_loading,
                     blueprints_assets_loaded,
@@ -132,16 +133,14 @@ impl Plugin for BlueprintsPlugin {
                     .chain()
                     .in_set(GltfBlueprintsSet::Spawn),
             )
-
             // animation
             .add_systems(
                 Update,
                 (
                     trigger_blueprint_animation_markers_events,
-                    trigger_instance_animation_markers_events
+                    trigger_instance_animation_markers_events,
                 ),
             )
-            
             // hot reload
             .add_systems(Update, react_to_asset_changes.run_if(hot_reload));
     }
diff --git a/crates/blenvy/src/blueprints/spawn_from_blueprints.rs b/crates/blenvy/src/blueprints/spawn_from_blueprints.rs
index 67b9c8a..dd8084f 100644
--- a/crates/blenvy/src/blueprints/spawn_from_blueprints.rs
+++ b/crates/blenvy/src/blueprints/spawn_from_blueprints.rs
@@ -1,6 +1,12 @@
 use std::path::Path;
 
-use bevy::{gltf::Gltf, prelude::*, scene::SceneInstance, utils::hashbrown::HashMap};
+use bevy::{
+    asset::{io::Reader, AssetLoader, AsyncReadExt, LoadContext},
+    gltf::Gltf,
+    prelude::*,
+    scene::SceneInstance,
+    utils::hashbrown::HashMap,
+};
 use serde_json::Value;
 
 use crate::{
@@ -115,17 +121,59 @@ Overview of the Blueprint Spawning process
  => distinguish between blueprint instances inside blueprint instances vs blueprint instances inside blueprints ??
 */
 
-pub(crate) fn blueprints_prepare_spawn(
+#[derive(Asset, TypePath, Debug)]
+pub struct RawGltfAsset(pub RawGltf);
+
+#[derive(Default)]
+pub(super) struct RawGltfAssetLoader;
+
+impl AssetLoader for RawGltfAssetLoader {
+    type Asset = RawGltfAsset;
+    type Settings = ();
+    type Error = gltf::Error;
+
+    async fn load<'a>(
+        &'a self,
+        reader: &'a mut Reader<'_>,
+        _settings: &'a (),
+        _load_context: &'a mut LoadContext<'_>,
+    ) -> Result<Self::Asset, Self::Error> {
+        let mut bytes = Vec::new();
+        reader.read_to_end(&mut bytes).await?;
+        let gltf = RawGltf::from_slice_without_validation(&bytes)?;
+        Ok(RawGltfAsset(gltf))
+    }
+}
+
+#[derive(Debug, Component, Deref, DerefMut)]
+#[component(storage = "SparseSet")]
+pub(super) struct AssociatedRawGltfHandle(Handle<RawGltfAsset>);
+
+pub(super) fn load_raw_gltf(
     blueprint_instances_to_spawn: Query<(Entity, &BlueprintInfo), Added<SpawnBlueprint>>,
+    asset_server: Res<AssetServer>,
+    mut commands: Commands,
+) {
+    for (entity, blueprint_info) in blueprint_instances_to_spawn.iter() {
+        let gltf_handle: Handle<RawGltfAsset> = asset_server.load(&blueprint_info.path);
+        commands
+            .entity(entity)
+            .insert(AssociatedRawGltfHandle(gltf_handle));
+    }
+}
+
+pub(super) fn blueprints_prepare_spawn(
+    blueprint_instances_to_spawn: Query<(Entity, &BlueprintInfo, &AssociatedRawGltfHandle)>,
     mut commands: Commands,
     asset_server: Res<AssetServer>,
     // for hot reload
     watching_for_changes: Res<WatchingForChanges>,
     mut assets_to_blueprint_instances: ResMut<AssetToBlueprintInstancesMapper>,
+    raw_gltf_assets: Res<Assets<RawGltfAsset>>,
     // for debug
     // all_names: Query<&Name>
 ) {
-    for (entity, blueprint_info) in blueprint_instances_to_spawn.iter() {
+    for (entity, blueprint_info, raw_gltf_handle) in blueprint_instances_to_spawn.iter() {
         info!(
             "BLUEPRINT: to spawn detected: {:?} path:{:?}",
             blueprint_info.name, blueprint_info.path
@@ -149,7 +197,9 @@ pub(crate) fn blueprints_prepare_spawn(
 
         // and we also add all its assets
         /* prefetch attempt */
-        let gltf = RawGltf::open(format!("assets/{}", blueprint_info.path)).unwrap();
+        let Some(RawGltfAsset(gltf)) = raw_gltf_assets.get(&raw_gltf_handle.0) else {
+            continue;
+        };
         for scene in gltf.scenes() {
             if let Some(scene_extras) = scene.extras().clone() {
                 let lookup: HashMap<String, Value> =
@@ -254,7 +304,10 @@ pub(crate) fn blueprints_prepare_spawn(
             .entity(entity)
             .insert(bevy::prelude::Name::from(blueprint_info.name.clone()));
         // add the blueprint spawning marker
-        commands.entity(entity).insert(BlueprintSpawning);
+        commands
+            .entity(entity)
+            .insert(BlueprintSpawning)
+            .remove::<AssociatedRawGltfHandle>();
     }
 }