Implement a "downcastable" wasm resource for ecs resources, cleanup code for exposing asset manager

csharp-guests.sln

@@ -3,7 +3,7 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 17
 VisualStudioVersion = 17.0.31903.59
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "dotnet-guest-test", "guests/csharp/dotnet-guest-test\dotnet-guest-test.csproj", "{68F96E6F-472F-409E-B36E-9C5E7206CCDE}"
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "dotnet-guest-test", "guests\csharp\dotnet-guest-test\dotnet-guest-test.csproj", "{68F96E6F-472F-409E-B36E-9C5E7206CCDE}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution

guests/csharp/dotnet-guest-test/ExampleWorldImpl.cs

@@ -1,39 +1,10 @@
 namespace ExampleWorld;
 
-using System.Diagnostics.CodeAnalysis;
-using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
 using ExampleWorld.wit.imports.lyra.api;
-using LyraApi;
+using LyraApi.Asset;
 using LyraApi.Ecs;
-
-[StructLayout(LayoutKind.Sequential)]
-struct Vec3(float x, float y, float z) : IComponent
-{
-    /// <summary>
-    /// The X component.
-    /// </summary>
-    public float X { get; set; } = x;
-    /// <summary>
-    /// The Y component
-    /// </summary>
-    public float Y { get; set; } = y;
-    /// <summary>
-    /// The Z component
-    /// </summary>
-    public float Z { get; set; } = z;
-
-    public static string HostName => "Vec3";
-    public static ulong HostSize => (ulong)Marshal.SizeOf<Vec3>();
-    public static ulong HostAlignment => (ulong)MarshalUtils.AlignmentOf<Vec3>();
-    public static ulong TypeId => 4124409524;
-
-    public static object? TakeFromBytes(byte[] bytes)
-    {
-        byte[] taken = bytes.Take((int)HostSize).ToArray();
-        return MarshalUtils.FromBytes<Vec3>(taken);
-    }
-}
+using LyraApi.Engine;
+using LyraApi.Math;
 
 public class ExampleWorldImpl : IExampleWorld
 {
@@ -47,6 +18,32 @@ public class ExampleWorldImpl : IExampleWorld
         {
             Console.WriteLine("C#:   Found entity at ({0}, {1}, {2})", comp.X, comp.Y, comp.Z);
         }
+
+        /* DeltaTime? dt = world.GetResource<DeltaTime>();
+        if (dt != null) {
+            Console.WriteLine($"C#:   Delta time: {dt?.Seconds:0.##}");
+        } */
+
+        AssetManager? man = world.GetResource<AssetManager>();
+        if (man != null) {
+            Handle<ImageHandle> han = man.Request<ImageHandle>("test_assets/white.png");
+            Console.WriteLine($"C#:   Asset uuid: {han.Uuid}");
+
+            // wait for asset to load before trying to get the data
+            han.WaitForLoadRecursive();
+            if (!han.IsLoaded)
+            {
+                Console.WriteLine("C#:   Asset is still not loaded, even after waiting!");
+            }
+
+            // will be null if the image hasn't loaded yet
+            ImageHandle? img = han.GetData();
+            Console.WriteLine($"C#:   Size of image: ({img?.Width}, {img?.Height})");
+        }
+        else
+        {
+            Console.WriteLine("C#:   No manager found");
+        }
     }
 
     public static void OnUpdate(IEcs.EcsWorld gameWorld, IEcs.Entity owningEntity)

guests/csharp/dotnet-guest-test/LyraApi/Asset/AssetManager.cs

@@ -0,0 +1,38 @@
+using LyraApi.Ecs;
+using ExampleWorld.wit.imports.lyra.api;
+using System.Numerics;
+
+namespace LyraApi.Asset;
+
+public class AssetManager(IAsset.AssetManager assetManager) : IResource
+{
+    internal IAsset.AssetManager inner = assetManager;
+
+    public static ulong TypeId => 567234789345;
+
+    public static object? FromWasmResult(IEcs.WorldResourceResult result)
+    {
+        switch (result.Tag)
+        {
+            case IEcs.WorldResourceResult.NONE:
+                return null;
+            case IEcs.WorldResourceResult.WASM_RESOURCE:
+                var handle = IAsset.AssetManager.FromEcsResource(result.AsWasmResource) ?? throw new MismatchedResourceResultException();
+                return new AssetManager(handle);
+            case IEcs.WorldResourceResult.BYTES:
+                return null;
+            default:
+                return null;
+        }
+    }
+
+    public UntypedHandle Request(string path)
+    {
+        return new UntypedHandle(inner.Request(path));
+    }
+
+    public Handle<T> Request<T>(string path) where T : IAssetHandle
+    {
+        return Request(path).AsHandle<T>();
+    }
+}

guests/csharp/dotnet-guest-test/LyraApi/Asset/Handle.cs

@@ -0,0 +1,34 @@
+namespace LyraApi.Asset;
+
+public class Handle<T>(UntypedHandle handle) where T : IAssetHandle
+{
+    internal UntypedHandle inner = handle;
+
+    public bool Watched { get => inner.Watched; }
+    public ulong Version { get => inner.Version; }
+    public Guid Uuid { get => inner.Uuid; }
+    public string? Path { get => inner.Path; }
+    public bool IsLoaded { get => inner.IsLoaded; }
+
+    public void WaitForLoad()
+    {
+        inner.WaitForLoad();
+    }
+
+    public void WaitForLoadRecursive()
+    {
+        inner.WaitForLoadRecursive();
+    }
+
+    public T? GetData()
+    {
+        if (IsLoaded)
+        {
+            return (T?)T.FromRawHandle(inner);
+        }
+        else
+        {
+            return default;
+        }
+    }
+}

guests/csharp/dotnet-guest-test/LyraApi/Asset/IAssetHandle.cs

@@ -0,0 +1,6 @@
+namespace LyraApi.Asset;
+
+public interface IAssetHandle
+{
+    public abstract static object? FromRawHandle(UntypedHandle untypedHandle);
+}

guests/csharp/dotnet-guest-test/LyraApi/Asset/ImageHandle.cs

@@ -0,0 +1,28 @@
+using ExampleWorld.wit.imports.lyra.api;
+
+namespace LyraApi.Asset;
+
+public class ImageHandle(IAsset.ImageHandle handle) : IAssetHandle
+{
+    internal IAsset.ImageHandle inner = handle;
+
+    public uint? Height => inner.Height();
+    public uint? Width => inner.Width();
+
+    public static object? FromRawHandle(UntypedHandle untypedHandle)
+    {
+        var handle = IAsset.ImageHandle.FromRawHandle(untypedHandle.inner);
+        return handle != null ? new ImageHandle(handle) : null;
+    }
+
+    /// <summary>
+    /// Get the image's pixels as native endian bytes.
+    /// </summary>
+    /// 
+    /// Keep in mind that this does copy the image's pixels from the host.
+    /// This is pretty slow.
+    public byte[]? GetImageBytes()
+    {
+        return inner.GetBytes();
+    }
+}

guests/csharp/dotnet-guest-test/LyraApi/Asset/UntypedHandle.cs

@@ -0,0 +1,29 @@
+using ExampleWorld.wit.imports.lyra.api;
+
+namespace LyraApi.Asset;
+
+public class UntypedHandle(IAsset.AssetHandle handle)
+{
+    internal IAsset.AssetHandle inner = handle;
+
+    public bool Watched { get => inner.IsWatched(); }
+    public ulong Version { get => inner.Version(); }
+    public Guid Uuid { get => Guid.Parse(inner.Uuid()); }
+    public string? Path { get => inner.Path(); }
+    public bool IsLoaded { get => inner.IsLoaded(); }
+
+    public void WaitForLoad()
+    {
+        inner.WaitForLoad();
+    }
+
+    public void WaitForLoadRecursive()
+    {
+        inner.WaitRecurseDependenciesLoad();
+    }
+
+    public Handle<T> AsHandle<T>() where T : IAssetHandle
+    {
+        return new Handle<T>(this);
+    }
+}

guests/csharp/dotnet-guest-test/LyraApi/Ecs/IResource.cs

@@ -0,0 +1,12 @@
+using static ExampleWorld.wit.imports.lyra.api.IEcs;
+
+namespace LyraApi.Ecs;
+
+public interface IResource
+{
+    public abstract static ulong TypeId { get; }
+
+    public abstract static object? FromWasmResult(WorldResourceResult result);
+}
+
+public class MismatchedResourceResultException : Exception {}

guests/csharp/dotnet-guest-test/LyraApi/Ecs/World.cs

@@ -2,15 +2,16 @@ namespace LyraApi.Ecs;
 
 using ExampleWorld.wit.imports.lyra.api;
 using LyraApi;
+using LyraApi.Asset;
 
 public class World(IEcs.EcsWorld world)
 {
-    private IEcs.EcsWorld Inner { get; set; } = world;
+    internal IEcs.EcsWorld inner = world;
 
     private Entity Spawn(List<IEcs.ComponentInfo> infos, params object[] comps)
     {
         byte[] bytes = comps.SelectMany(c => MarshalUtils.GetBytes(c)).ToArray();
-        return new Entity(Inner.Spawn(bytes, infos));
+        return new Entity(inner.Spawn(bytes, infos));
     }
 
     public Entity Spawn<T1>(T1 c1) where T1 : IComponent
@@ -24,7 +25,27 @@ public class World(IEcs.EcsWorld world)
         List<Component> comps = [Component.FromComponent<T1>()];
         List<IEcs.ComponentInfo> infos = comps.Select(c => c.GetComponentInfo().info).ToList();
 
-        IEcs.EcsDynamicView dynamicView = Inner.View(infos);
+        IEcs.EcsDynamicView dynamicView = inner.View(infos);
         return new ViewResult(comps, dynamicView).Get<T1>();
     }
+
+    public T? GetResource<T>() where T : IResource
+    {
+        IEcs.WorldResourceResult result = inner.GetResource(Utils.ToWasmTypeId(T.TypeId));
+        return (T?)T.FromWasmResult(result);
+    }
+
+    /* public AssetManager? GetAssetManager()
+    {
+        IAsset.AssetManager? assetManager = IAsset.AssetManager.FromWorld(inner);
+
+        if (assetManager != null)
+        {
+            return new AssetManager(assetManager);
+        }
+        else
+        {
+            return null;
+        }
+    } */
 }

guests/csharp/dotnet-guest-test/LyraApi/Engine/DeltaTime.cs

@@ -0,0 +1,23 @@
+using System.Runtime.InteropServices;
+using LyraApi;
+using LyraApi.Ecs;
+using static ExampleWorld.wit.imports.lyra.api.IEcs;
+
+namespace LyraApi.Engine;
+
+[StructLayout(LayoutKind.Sequential)]
+public struct DeltaTime : IResource {
+    public float Seconds;
+
+    public static ulong TypeId => 83716348954;
+
+    public static object? FromWasmResult(WorldResourceResult result)
+    {
+        return result.Tag switch
+        {
+            WorldResourceResult.NONE | WorldResourceResult.WASM_RESOURCE => null,
+            WorldResourceResult.BYTES => MarshalUtils.FromBytes<DeltaTime>(result.AsBytes),
+            _ => null,
+        };
+    }
+}

guests/csharp/dotnet-guest-test/LyraApi/Math/Vec3.cs

@@ -0,0 +1,32 @@
+using System.Runtime.InteropServices;
+using LyraApi.Ecs;
+
+namespace LyraApi.Math;
+
+[StructLayout(LayoutKind.Sequential)]
+struct Vec3(float x, float y, float z) : IComponent
+{
+    /// <summary>
+    /// The X component.
+    /// </summary>
+    public float X { get; set; } = x;
+    /// <summary>
+    /// The Y component
+    /// </summary>
+    public float Y { get; set; } = y;
+    /// <summary>
+    /// The Z component
+    /// </summary>
+    public float Z { get; set; } = z;
+
+    public static string HostName => "Vec3";
+    public static ulong HostSize => (ulong)Marshal.SizeOf<Vec3>();
+    public static ulong HostAlignment => (ulong)MarshalUtils.AlignmentOf<Vec3>();
+    public static ulong TypeId => 4124409524;
+
+    public static object? TakeFromBytes(byte[] bytes)
+    {
+        byte[] taken = bytes.Take((int)HostSize).ToArray();
+        return MarshalUtils.FromBytes<Vec3>(taken);
+    }
+}

guests/csharp/dotnet-guest-test/LyraApi/Utils.cs

@@ -0,0 +1,8 @@
+using static ExampleWorld.wit.imports.lyra.api.IEcs;
+
+internal static class Utils {
+    public static WasmTypeId ToWasmTypeId(ulong typeId)
+    {
+        return new WasmTypeId((typeId, 0));
+    }
+}

guests/csharp/dotnet-guest-test/dotnet-guest-test.csproj

@@ -18,12 +18,16 @@
   </PropertyGroup>
 
   <!-- Copy WIT files from LyraApi to lyra-api wit folder. -->
-  <!-- <Target Name="CopyFolderOnBuild" BeforeTargets="WitCompile_InvokeTool">
+  <Target Name="CopyLyraApiWit" BeforeTargets="WitCompile_InvokeTool">
     <ItemGroup>
-      <MyFiles Include="..\LyraApi\wit\**\*.wit" />
+      <MyFiles Include="..\..\rust\common-api\wit\**\*.wit" />
     </ItemGroup>
     <Copy SourceFiles="@(MyFiles)" DestinationFolder="wit\deps\lyraapi\%(RecursiveDir)" />
-  </Target> -->
+  </Target>
+
+  <Target Name="CopyComponentGuestWit" BeforeTargets="WitCompile_InvokeTool">
+    <Copy SourceFiles="..\..\rust\witguest\wit\world.wit" DestinationFiles="wit\world.wit" />
+  </Target>
 
   <!-- Remove bindgen of LyraApi WIT .-->
   <!-- <Target Name="RemoveBindgenLyraApi" AfterTargets="WitCompile_InvokeTool">

guests/csharp/dotnet-guest-test/wit/deps/lyraapi/asset.wit

@@ -0,0 +1,26 @@
+interface asset {
+    use ecs.{ecs-world, ecs-resource};
+
+    resource asset-handle {
+        version: func() -> u64;
+        uuid: func() -> string;
+        path: func() -> option<string>;
+        is-watched: func() -> bool;
+        is-loaded: func() -> bool;
+        wait-for-load: func();
+        wait-recurse-dependencies-load: func();
+    }
+
+    resource image-handle {
+        from-raw-handle: static func(raw-handle: borrow<asset-handle>) -> option<image-handle>;
+
+        height: func() -> option<u32>;
+        width: func() -> option<u32>;
+        get-bytes: func() -> option<list<u8>>;
+    }
+
+    resource asset-manager {
+        from-ecs-resource: static func(w: borrow<ecs-resource>) -> option<asset-manager>;
+        request: func(path: string) -> asset-handle;
+    }
+}

guests/csharp/dotnet-guest-test/wit/deps/lyraapi/ecs.wit

@@ -37,6 +37,19 @@ interface ecs {
         next: func() -> option<tuple<entity, list<u8>>>;
     }
 
+    /// An resource that can be "downcasted" to a specific type.
+    /// 
+    /// You can use `T.from-ecs-resource` to "downcast" the type
+    resource ecs-resource {
+
+    }
+
+    variant world-resource-result {
+        none,
+        wasm-resource(ecs-resource),
+        bytes(list<u8>),
+    }
+
     resource ecs-world {
         constructor();
 
@@ -76,6 +89,8 @@ interface ecs {
         /// Returns: A row of components serialized as bytes. The buffer is tighly packed.
         view-one: func(en: entity, component-infos: list<component-info>) -> option<list<u8>>;
 
+        get-resource: func(type-id: wasm-type-id) -> world-resource-result;
+
         //with_system: func(stage: string, component-infos: list<component-info>, system: func(components: list<u8>));
     }
 }

guests/csharp/dotnet-guest-test/wit/deps/lyraapi/world.wit

@@ -2,4 +2,5 @@ package lyra:api;
 
 world imports {
     import ecs;
+    import asset;
 }

guests/csharp/dotnet-guest-test/wit/world.wit

@@ -11,6 +11,7 @@ interface math {
 /// An example world for the component to target.
 world example {
     import math;
+    import lyra:api/asset;
     use lyra:api/ecs.{ecs-world, entity};
 
     import host-print: func(msg: string);

guests/rust/common-api/src/resource/dt.rs

@@ -20,7 +20,7 @@ impl EcsResource for DeltaTime {
     fn from_wasm_result(result: &WorldResourceResult) -> Option<Self> {
         match result {
             WorldResourceResult::None => None,
-            WorldResourceResult::WasmResourceRep(_) => None,
+            WorldResourceResult::WasmResource(_) => None,
             WorldResourceResult::Bytes(vec) => Some(Self(*bytemuck::from_bytes::<f32>(&vec))),
         }
     }

guests/rust/common-api/wit/asset.wit

@@ -0,0 +1,26 @@
+interface asset {
+    use ecs.{ecs-world, ecs-resource};
+
+    resource asset-handle {
+        version: func() -> u64;
+        uuid: func() -> string;
+        path: func() -> option<string>;
+        is-watched: func() -> bool;
+        is-loaded: func() -> bool;
+        wait-for-load: func();
+        wait-recurse-dependencies-load: func();
+    }
+
+    resource image-handle {
+        from-raw-handle: static func(raw-handle: borrow<asset-handle>) -> option<image-handle>;
+
+        height: func() -> option<u32>;
+        width: func() -> option<u32>;
+        get-bytes: func() -> option<list<u8>>;
+    }
+
+    resource asset-manager {
+        from-ecs-resource: static func(w: borrow<ecs-resource>) -> option<asset-manager>;
+        request: func(path: string) -> asset-handle;
+    }
+}

guests/rust/common-api/wit/ecs.wit

@@ -37,9 +37,16 @@ interface ecs {
         next: func() -> option<tuple<entity, list<u8>>>;
     }
 
+    /// An resource that can be "downcasted" to a specific type.
+    /// 
+    /// You can use `T.from-ecs-resource` to "downcast" the type
+    resource ecs-resource {
+
+    }
+
     variant world-resource-result {
         none,
-        wasm-resource-rep(u32),
+        wasm-resource(ecs-resource),
         bytes(list<u8>),
     }
 

guests/rust/common-api/wit/world.wit

@@ -2,4 +2,5 @@ package lyra:api;
 
 world imports {
     import ecs;
+    import asset;
 }

guests/rust/witguest/src/lib.rs

@@ -5,6 +5,7 @@ wit_bindgen::generate!({
 
     with: {
         "lyra:api/ecs": common_api::bindings::lyra::api::ecs,
+        "lyra:api/asset": common_api::bindings::lyra::api::asset,
     },
 });
 

guests/rust/witguest/wit/deps/lyraapi/asset.wit

@@ -0,0 +1,26 @@
+interface asset {
+    use ecs.{ecs-world, ecs-resource};
+
+    resource asset-handle {
+        version: func() -> u64;
+        uuid: func() -> string;
+        path: func() -> option<string>;
+        is-watched: func() -> bool;
+        is-loaded: func() -> bool;
+        wait-for-load: func();
+        wait-recurse-dependencies-load: func();
+    }
+
+    resource image-handle {
+        from-raw-handle: static func(raw-handle: borrow<asset-handle>) -> option<image-handle>;
+
+        height: func() -> option<u32>;
+        width: func() -> option<u32>;
+        get-bytes: func() -> option<list<u8>>;
+    }
+
+    resource asset-manager {
+        from-ecs-resource: static func(w: borrow<ecs-resource>) -> option<asset-manager>;
+        request: func(path: string) -> asset-handle;
+    }
+}

guests/rust/witguest/wit/deps/lyraapi/ecs.wit

@@ -37,9 +37,16 @@ interface ecs {
         next: func() -> option<tuple<entity, list<u8>>>;
     }
 
+    /// An resource that can be "downcasted" to a specific type.
+    /// 
+    /// You can use `T.from-ecs-resource` to "downcast" the type
+    resource ecs-resource {
+
+    }
+
     variant world-resource-result {
         none,
-        wasm-resource-rep(u32),
+        wasm-resource(ecs-resource),
         bytes(list<u8>),
     }
 

guests/rust/witguest/wit/deps/lyraapi/world.wit

@@ -2,4 +2,5 @@ package lyra:api;
 
 world imports {
     import ecs;
+    import asset;
 }

guests/rust/witguest/wit/world.wit

@@ -11,6 +11,7 @@ interface math {
 /// An example world for the component to target.
 world example {
     import math;
+    import lyra:api/asset;
     use lyra:api/ecs.{ecs-world, entity};
 
     import host-print: func(msg: string);

mise.toml

@@ -0,0 +1,2 @@
+[tools]
+dotnet = "9.0.100-rc.2.24474.11"

src/asset.rs

@@ -0,0 +1,145 @@
+use async_trait::async_trait;
+use wasmtime::component::Resource as WasmResource;
+
+use crate::{lyra, Imports};
+
+use lyra::api::asset as wasm_asset;
+use lyra::api::ecs as wasm_ecs;
+
+impl wasm_asset::Host for Imports {}
+
+#[async_trait]
+impl wasm_asset::HostAssetManager for Imports {
+    async fn from_ecs_resource(&mut self, res: WasmResource<wasm_ecs::EcsResource>) -> Option<WasmResource<wasm_asset::AssetManager>> {
+        let res_rep = res.rep() as u32;
+        let res = self.resource_data_slab.get_mut(res_rep as _)?;
+        res.borrow += 1;
+
+        // ensure that the 
+        if !res.data.is::<lyra_engine::assets::ResourceManager>() {
+            return None;
+        }
+        
+        Some(WasmResource::new_own(res_rep as _))
+    }
+
+    async fn request(
+        &mut self,
+        this: WasmResource<wasm_asset::AssetManager>,
+        path: String,
+    ) -> WasmResource<wasm_asset::AssetHandle> {
+        let man = self.resource_data_slab.get(this.rep() as _)
+            .unwrap()
+            .data.get::<lyra_engine::assets::ResourceManager>();
+        let res = man.request_raw(&path).unwrap();
+        let rep = self.asset_handles_slab.insert(res);
+        WasmResource::new_own(rep as _)
+    }
+
+    async fn drop(&mut self, this: WasmResource<wasm_asset::AssetManager>) -> wasmtime::Result<()> {
+        self.resource_data_slab.drop_ref(this.rep() as _);
+        Ok(())
+    }
+}
+
+#[async_trait]
+impl wasm_asset::HostAssetHandle for Imports {
+    async fn version(&mut self, this: WasmResource<wasm_asset::AssetHandle>) -> u64 {
+        let han = self.asset_handles_slab.get(this.rep() as _)
+            .unwrap();
+        han.version() as u64
+    }
+
+    async fn uuid(&mut self, this: WasmResource<wasm_asset::AssetHandle>) -> String {
+        let han = self.asset_handles_slab.get(this.rep() as _)
+            .unwrap();
+        han.uuid().to_string()
+    }
+
+    async fn path(&mut self, this: WasmResource<wasm_asset::AssetHandle>) -> Option<String> {
+        let han = self.asset_handles_slab.get(this.rep() as _)
+            .unwrap();
+        han.path()
+    }
+
+    async fn is_watched(&mut self, this: WasmResource<wasm_asset::AssetHandle>) -> bool {
+        let han = self.asset_handles_slab.get(this.rep() as _)
+            .unwrap();
+        han.is_watched()
+    }
+
+    async fn is_loaded(&mut self, this: WasmResource<wasm_asset::AssetHandle>) -> bool {
+        let han = self.asset_handles_slab.get(this.rep() as _)
+            .unwrap();
+        han.is_loaded()
+    }
+
+    async fn wait_for_load(&mut self, this: WasmResource<wasm_asset::AssetHandle>) {
+        let han = self.asset_handles_slab.get(this.rep() as _)
+            .unwrap().clone();
+
+        tokio::task::spawn_blocking(move || {
+            han.wait_for_load();
+        }).await.unwrap();
+    }
+
+    async fn wait_recurse_dependencies_load(
+        &mut self,
+        this: WasmResource<wasm_asset::AssetHandle>,
+    ) {
+        let han = self.asset_handles_slab.get(this.rep() as _)
+            .unwrap().clone();
+
+        tokio::task::spawn_blocking(move || {
+            han.wait_recurse_dependencies_load();
+        }).await.unwrap();
+    }
+
+    async fn drop(&mut self, this: WasmResource<wasm_asset::AssetHandle>) -> wasmtime::Result<()> {
+        self.asset_handles_slab.drop_ref(this.rep() as _);
+        Ok(())
+    }
+}
+
+#[async_trait]
+impl wasm_asset::HostImageHandle for Imports {
+    async fn from_raw_handle(&mut self, raw_handle: WasmResource<wasm_asset::AssetHandle>) -> Option<WasmResource<wasm_asset::ImageHandle>> {
+        let untyped = self.asset_handles_slab.get(raw_handle.rep() as _)?;
+        // image will be none if the asset is not an image asset
+        let image = untyped.as_typed::<lyra_engine::assets::Image>();
+        if image.is_some() {
+            let rep = raw_handle.rep();
+            self.asset_handles_slab.increment_ref(rep as _);
+
+            Some(WasmResource::new_own(rep))
+        } else {
+            None
+        }
+    }
+
+    async fn height(&mut self, this: WasmResource<wasm_asset::ImageHandle>) -> Option<u32> {
+        let untyped = self.asset_handles_slab.get(this.rep() as _)?;
+        let image = untyped.as_typed::<lyra_engine::assets::Image>()?;
+        let image = image.data_ref()?;
+        Some(image.height())
+    }
+
+    async fn width(&mut self, this: WasmResource<wasm_asset::ImageHandle>) -> Option<u32> {
+        let untyped = self.asset_handles_slab.get(this.rep() as _)?;
+        let image = untyped.as_typed::<lyra_engine::assets::Image>()?;
+        let image = image.data_ref()?;
+        Some(image.width())
+    }
+
+    async fn get_bytes(&mut self, this: WasmResource<wasm_asset::ImageHandle>) -> Option<Vec<u8>> {
+        let untyped = self.asset_handles_slab.get(this.rep() as _)?;
+        let image = untyped.as_typed::<lyra_engine::assets::Image>()?;
+        let image = image.data_ref()?;
+        Some(image.as_bytes().to_vec())
+    }
+
+    async fn drop(&mut self, this: WasmResource<wasm_asset::ImageHandle>) -> wasmtime::Result<()> {
+        self.asset_handles_slab.drop_ref(this.rep() as _);
+        Ok(())
+    }
+}

src/main.rs

@@ -9,12 +9,12 @@ use async_trait::async_trait;
 use common_api::math::Vec3;
 use component::witguest::math;
 use ecs::query::dynamic::{DynamicViewState, DynamicViewStateIter, QueryDynamicType};
-use lyra_ecs::{query::dynamic::DynamicViewOne, DynTypeId, World};
+use lyra_ecs::{query::dynamic::DynamicViewOne, World};
 
 use lyra_ecs as ecs;
 
-use ::lyra_engine::DeltaTime;
-use lyra_reflect::{FromType, ReflectedResource, RegisteredType, TypeRegistry};
+use lyra_engine::DeltaTime;
+use lyra_reflect::{ReflectedResource, TypeRegistry};
 use slab::Slab;
 use thiserror::Error;
 use wasmtime_wasi::{ResourceTable, WasiCtx, WasiCtxBuilder, WasiView};
@@ -24,10 +24,14 @@ use wasmtime::component::Resource as WasmResource;
 mod proxy;
 pub use proxy::*;
 
+mod asset;
 #[allow(unused_imports)]
+pub use asset::*;
+
+/* #[allow(unused_imports)]
 pub(crate) mod lyra_engine {
     pub use lyra_ecs as ecs;
-}
+} */
 
 wasmtime::component::bindgen!({
     world: "example",
@@ -82,14 +86,87 @@ struct DynamicViewEntry {
     view: DynamicViewStateIter,
 }
 
+#[derive(Clone)]
+pub(crate) struct RefCountedData<T> {
+    pub borrow: u64,
+    pub data: T,
+}
+
+impl<T> std::ops::Deref for RefCountedData<T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        &self.data
+    }
+}
+
+impl<T> std::ops::DerefMut for RefCountedData<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.data
+    }
+}
+
+/// A Slab of reference counted data.
+pub(crate) struct SlabRcData<T>(Slab<RefCountedData<T>>);
+
+impl<T> From<Slab<RefCountedData<T>>> for SlabRcData<T> {
+    fn from(value: Slab<RefCountedData<T>>) -> Self {
+        Self(value)
+    }
+}
+
+impl<T> std::ops::Deref for SlabRcData<T> {
+    type Target = Slab<RefCountedData<T>>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl<T> std::ops::DerefMut for SlabRcData<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+
+impl<T> SlabRcData<T> {
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self(Slab::with_capacity(capacity))
+    }
+
+    pub fn increment_ref(&mut self, r: usize) {
+        if let Some(count) = self.0.get_mut(r) {
+            count.borrow += 1;
+        }
+    }
+
+    pub fn drop_ref(&mut self, r: usize) {
+        if let Some(count) = self.0.get_mut(r) {
+            // only remove the data from the slab if this is the only borrow
+            if count.borrow == 1 {
+                self.0.remove(r);
+            } else {
+                count.borrow -= 1;
+            }
+        }
+    }
+
+    /// Insert a new reference counted element into the slab.
+    pub fn insert(&mut self, data: T) -> usize {
+        self.0.insert(RefCountedData { borrow: 1, data, })
+    }
+}
+
 unsafe impl Send for DynamicViewEntry {}
 
-struct Imports {
-    world_slab: Slab<WorldEntry>,
-    world_views_slab: Slab<DynamicViewEntry>,
+pub struct Imports {
+    pub(crate) world_slab: Slab<WorldEntry>,
+    pub(crate) world_views_slab: Slab<DynamicViewEntry>,
+    pub(crate) resource_data_slab: SlabRcData<lyra_ecs::ResourceData>,
+    pub(crate) asset_handles_slab: SlabRcData<lyra_engine::assets::UntypedResHandle>,
 
-    ctx: WasiCtx,
-    table: ResourceTable,
+    pub(crate) ctx: WasiCtx,
+    pub(crate) table: ResourceTable,
 }
 
 impl WasiView for Imports {
@@ -251,23 +328,39 @@ impl wasm_ecs::HostEcsWorld for Imports {
     async fn get_resource(&mut self, this: wasmtime::component::Resource<wasm_ecs::EcsWorld>, type_id: wasm_ecs::WasmTypeId) -> wasm_ecs::WorldResourceResult {
         let world_entry = self
             .world_slab
-            .try_remove(this.rep() as _)
+            .get(this.rep() as _)
             .ok_or(WasmError::InvalidResourceHandle("EcsWorld")).unwrap();
         let world = &world_entry.world;
 
-        let native_type = world.get_resource::<GuestTypeLookup>().unwrap();
-        let native_tid = native_type.lookup_type_id(type_id)
-            .expect("failed to find native type id of wasm type");
+        let native_tid = {
+            let native_type = world.get_resource::<GuestTypeLookup>().unwrap();
+            native_type.lookup_type_id(type_id)
+                .expect("failed to find native type id of wasm type")
+        };
 
-        let reg = world.get_resource::<TypeRegistry>().unwrap();
-        let data = reg.get_type(native_tid).unwrap();
-        let proxy = data.get_data::<WasmProxied>().unwrap();
+        let data = {
+            let reg = world.get_resource::<TypeRegistry>().unwrap();
+            reg.get_type(native_tid).unwrap().clone()
+        };
 
-        let refl = data.get_data::<ReflectedResource>().unwrap();
+        let proxy = data.get_data::<WasmProxied>().unwrap().clone();        
+        let refl = data.get_data::<ReflectedResource>().unwrap().clone();
+
+        // SAFETY: reflecting the resource borrows from a different part of the world
+        // then marshaling would.
+        let w = NonNull::from(world);
+        let world = unsafe { w.as_ref() };
         let refl = refl.reflect(world).unwrap();
-        let res = proxy.marshal_to_bytes(refl.deref());
+        let res = proxy.marshal_to_bytes(self, this.rep(), refl.deref());
 
-        res
+        match res {
+            ProxyResult::None => wasm_ecs::WorldResourceResult::None,
+            ProxyResult::Bytes(bytes) => wasm_ecs::WorldResourceResult::Bytes(bytes),
+            ProxyResult::WasmResource(data) => {
+                let rep = self.resource_data_slab.insert(data);
+                wasm_ecs::WorldResourceResult::WasmResource(WasmResource::new_own(rep as _))
+            }
+        }
     }
 
     async fn drop(
@@ -425,6 +518,18 @@ impl GuestTypeLookup {
     }
 }
 
+#[async_trait]
+impl wasm_ecs::HostEcsResource for Imports {
+    async fn drop(
+        &mut self,
+        this: wasmtime::component::Resource<wasm_ecs::EcsResource>,
+    ) -> wasmtime::Result<()> {
+        self.resource_data_slab.drop_ref(this.rep() as _);
+
+        Ok(())
+    }
+}
+
 #[async_trait]
 impl wasm_ecs::Host for Imports {}
 
@@ -439,12 +544,8 @@ async fn main() -> wasmtime::Result<()> {
     // Configure the linker
     let mut linker = wasmtime::component::Linker::new(&engine);
 
-    //wasmtime_wasi::preview0::add_to_linker_sync(&mut linker, |s| s)?;
-    //wasmtime_wasi::bindings::Imports::add_to_linker(&mut linker, |s| s)?;
     wasmtime_wasi::add_to_linker_async(&mut linker)?;
     Example::add_to_linker(&mut linker, |s| s)?;
-    //lyra::api::ecs::add_to_linker(&mut linker, |s| s)?;
-    //Api::add_to_linker(&mut linker, |s| s)?;
 
     let mut builder = WasiCtxBuilder::new();
     builder.inherit_stdio();
@@ -456,34 +557,34 @@ async fn main() -> wasmtime::Result<()> {
             // wants another world for some reason.
             world_slab: Slab::with_capacity(1),
             world_views_slab: Slab::with_capacity(10),
+            resource_data_slab: SlabRcData::with_capacity(25),
+            asset_handles_slab: SlabRcData::with_capacity(25),
             ctx: builder.build(),
             table: ResourceTable::new(),
         },
     );
 
     // Load the component from disk
-    let bytes = std::fs::read("target/wasm32-wasip1/debug/witguest-component.wasm")?;
-    //let bytes = std::fs::read("guests/csharp/dotnet-guest-test/bin/Debug/net9.0/wasi-wasm/native/dotnet-guest-test.wasm")?;
+    //let bytes = std::fs::read("target/wasm32-wasip1/debug/witguest-component.wasm")?;
+    let bytes = std::fs::read("guests/csharp/dotnet-guest-test/bin/Debug/net9.0/wasi-wasm/native/dotnet-guest-test.wasm")?;
     let component = wasmtime::component::Component::new(&engine, bytes)?;
 
-    let (script_en, (world_res_a, world_res_b)) = {
+    let (script_en, (world_res_a, _)) = {
         let mut world = World::new();
 
         world.add_resource(DeltaTime::from(100.00));
+        world.add_resource(lyra_engine::assets::ResourceManager::default());
         
         let mut lookup = GuestTypeLookup::default();
         lookup.infos.insert(4124409524, lyra_ecs::ComponentInfo::new::<Vec3>());
-        lookup.type_ids.insert(83716348954, TypeId::of::<::lyra_engine::DeltaTime>());
+        lookup.type_ids.insert(83716348954, TypeId::of::<lyra_engine::DeltaTime>());
+        lookup.type_ids.insert(567234789345, TypeId::of::<lyra_engine::assets::ResourceManager>());
         world.add_resource(lookup);
 
         {
             let mut reg = world.get_resource_or_default::<TypeRegistry>();
-
-            let mut dt_type = RegisteredType::new();
-            dt_type.add_data(<ReflectedResource as FromType::<DeltaTime>>::from_type());
-            dt_type.add_data(<WasmProxied as FromType::<DeltaTime>>::from_type());
-
-            reg.add_registered_type(TypeId::of::<DeltaTime>(), dt_type);
+            add_proxy_type_data::<DeltaTime>(&mut reg);
+            add_proxy_type_data::<lyra_engine::assets::ResourceManager>(&mut reg);
         }
 
         let script_en = world.spawn(());
@@ -507,36 +608,6 @@ async fn main() -> wasmtime::Result<()> {
     //call_script_stage_async(&mut store, &instance, "update", world_res_b, script_en.into()).await?;
     println!("RUST: Guest is done");
 
-    let rep = world_res_b.rep();
-    if let Some(w) = store.data().world_slab.get(rep as _) {
-        let w = &w.world;
-        println!("RUST: Got {} archetypes", w.archetype_count());
-        for a in w.archetypes.values() {
-            println!("RUST: Archetype {}", a.id().0);
-            for col in &a.columns {
-                println!("RUST:   Column type id: {:?}", col.info.type_id());
-
-                if col.info.type_id().is_id(DynTypeId::Unknown(4124409524)) {
-                    println!("RUST:     Found C# Vec3");
-                    let pos = unsafe { col.get::<Vec3>(0) };
-                    println!("RUST:     Entity 0 pos: {:?}", *pos);
-                }
-            }
-        }
-
-        let mut dv = w.dynamic_view();
-        dv.push(QueryDynamicType::from_info(lyra_ecs::ComponentInfo::new::<Vec3>()));
-        let iter = dv.into_iter();
-
-        for (_, comps) in iter {
-            let first = comps.first().unwrap();
-            unsafe {
-                let v: Vec3 = std::ptr::read(first.ptr.as_ptr() as _);
-                println!("RUST: Found native Vec3! {:?}", v);
-            }
-        }
-    }
-
     Ok(())
 }
 

src/proxy.rs

@@ -1,20 +1,28 @@
-use crate::lyra::api::ecs as wasm_ecs;
+use std::any::TypeId;
+
+use crate::Imports;
 use common_api::bytemuck;
 use lyra_engine::DeltaTime;
-use lyra_reflect::{FromType, Reflect};
+use lyra_reflect::{FromType, Reflect, ReflectedResource, TypeRegistry};
+
+pub enum ProxyResult {
+    None,
+    WasmResource(lyra_ecs::ResourceData),
+    Bytes(Vec<u8>)
+}
 
 pub trait WasmProxy {
-    fn marshal_to_bytes(&self) -> wasm_ecs::WorldResourceResult;
+    fn marshal_to_bytes(&self, imports: &mut Imports, world_idx: u32) -> ProxyResult;
 }
 
 #[derive(Clone)]
 pub struct WasmProxied {
-    fn_marshal: for<'a> fn (&'a dyn Reflect) -> wasm_ecs::WorldResourceResult,
+    fn_marshal: for<'a> fn (&mut Imports, world_idx: u32, &'a dyn Reflect) -> ProxyResult,
 }
 
 impl WasmProxied {
-    pub fn marshal_to_bytes(&self, reflected: &dyn Reflect) -> wasm_ecs::WorldResourceResult {
-        (self.fn_marshal)(reflected)
+    pub fn marshal_to_bytes(&self, imports: &mut Imports, world_idx: u32, reflected: &dyn Reflect) -> ProxyResult {
+        (self.fn_marshal)(imports, world_idx, reflected)
     }
 }
 
@@ -24,16 +32,33 @@ where
 {
     fn from_type() -> Self {
         WasmProxied {
-            fn_marshal: |reflect| {
+            fn_marshal: |imports, world_idx: u32, reflect| {
                 let this: &T = reflect.as_any().downcast_ref().unwrap();
-                this.marshal_to_bytes()
+                this.marshal_to_bytes(imports, world_idx)
             }
         }
     }
 }
 
+pub fn add_proxy_type_data<T: WasmProxy + lyra_ecs::ResourceObject + lyra_reflect::Reflect>(reg: &mut TypeRegistry) {
+    let ty = reg.get_type_or_default(TypeId::of::<T>());
+    ty.add_data(<ReflectedResource as FromType::<T>>::from_type());
+    ty.add_data(<WasmProxied as FromType::<T>>::from_type());
+}
+
 impl WasmProxy for DeltaTime {
-    fn marshal_to_bytes(&self) -> wasm_ecs::WorldResourceResult {
-        wasm_ecs::WorldResourceResult::Bytes(bytemuck::bytes_of(&**self).to_vec())
+    fn marshal_to_bytes(&self, _: &mut Imports, _: u32) -> ProxyResult {
+        ProxyResult::Bytes(bytemuck::bytes_of(&**self).to_vec())
+    }
+}
+
+impl WasmProxy for lyra_engine::assets::ResourceManager {
+    fn marshal_to_bytes(&self, imports: &mut Imports, world_idx: u32) -> ProxyResult {
+        let world = &imports.world_slab.get(world_idx as _)
+            .unwrap().world;
+        match world.get_resource_data::<Self>() {
+            Some(data) => ProxyResult::WasmResource(data),
+            None => ProxyResult::None,
+        }
     }
 }