Engine: More PBR shader and loading support, working on asset system with ReferenceCount support (WIP)

amerkoleci · amerkoleci · commit d3cbef89e7f9 · 2026-02-20T13:55:02.000+01:00
diff --git a/assets/Shaders/PBR.slang b/assets/Shaders/PBR.slang
@@ -28,12 +28,13 @@ struct SurfaceInfo
 // Material (space 0)
 ConstantBuffer<PBRMaterialData> material : register(b0);
 Texture2D<float4> baseColorTexture : register(t0);
-SamplerState baseColorSampler : register(s0);
+Texture2D<float4> normalTexture : register(t1);
+SamplerState pbrSampler : register(s0);
 
 [shader("pixel")]
 float4 fragmentMain(in VertexOutput input, in bool isFrontFace: SV_IsFrontFace) : SV_TARGET
 {
-    const float4 baseColorMap = baseColorTexture.Sample(baseColorSampler, input.TexCoord0);
+    const float4 baseColorMap = baseColorTexture.Sample(pbrSampler, input.TexCoord0);
 
     // float4 baseColor = material.baseColorFactor * baseColorTexture.Sample(SamplerLinearClamp, input.TexCoord0);
     float4 baseColor = material.baseColorFactor * baseColorMap;
@@ -46,6 +47,18 @@ float4 fragmentMain(in VertexOutput input, in bool isFrontFace: SV_IsFrontFace)
 
     // Should we normalize here?
     float3x3 TBN = float3x3(input.Tangent, input.Bitangent, input.Normal);
+    //[branch]
+    // if (material.textures[NORMALMAP].IsValid())
+    {
+        float3 N = float3(normalTexture.Sample(pbrSampler, input.TexCoord0).rg, 1.f);
+        N = N * 2.f - 1.f;
+        //N.rg *= material.GetNormalMapStrength();
+        surface.N = normalize(mul(N, TBN));
+        if (!isFrontFace) // MATERIAL_DOUBLE_SIDED?
+        {
+            surface.N = -surface.N;
+        }
+    }
 
     return baseColor;
 }
diff --git a/samples/Alimer.Samples/Engine/ScenePBRRendererSample.cs b/samples/Alimer.Samples/Engine/ScenePBRRendererSample.cs
@@ -28,7 +28,7 @@ public ScenePBRRendererSample(IServiceRegistry services)
         // Camera
         _cameraEntity = new();
         CameraComponent camera = _cameraEntity.AddComponent<CameraComponent>();
-        camera.Entity!.Transform.Position = new Vector3(0.0f, 0.0f, 25.0f);
+        camera.Entity!.Transform.Position = new Vector3(0.0f, 0.0f, 5.0f);
         root.Children.Add(_cameraEntity);
 
         // GLTF mesh
@@ -83,7 +83,7 @@ public ScenePBRRendererSample(IServiceRegistry services)
     public override void Update(GameTime time)
     {
         float deltaTime = (float)time.Elapsed.TotalSeconds;
-        _damagedHelmetEntity.Transform.Rotate(10 * deltaTime, 20 * deltaTime, 30 * deltaTime);
+        //_damagedHelmetEntity.Transform.Rotate(10 * deltaTime, 20 * deltaTime, 30 * deltaTime);
     }
 
     public override void Draw(CommandBuffer context, Texture swapChainTexture)
diff --git a/src/Alimer/Assets/Asset.cs b/src/Alimer/Assets/Asset.cs
@@ -6,17 +6,63 @@ namespace Alimer.Assets;
 /// <summary>
 /// Base class for Asset.
 /// </summary>
-public abstract class Asset
+public abstract class Asset : IAsset
 {
-    /// <summary>
-    /// Gets or sets the name of the asset.
-    /// </summary>
-    public string? Name { get;set; }
+    private volatile uint _refCount =1;
 
+    /// <inheritdoc />
     public Guid Id { get; set; } = Guid.NewGuid();
 
+    /// <inheritdoc />
+    public string Name { get; set; } = string.Empty;
+
+    /// <inheritdoc/>
+    public uint ReferenceCount { get { return _refCount; } }
+
+    protected Asset()
+    {
+    }
+
+    /// <inheritdoc cref="IReferencable.AddReference()" />
+    public virtual uint AddReference()
+    {
+        uint newRefCount = Interlocked.Increment(ref _refCount);
+        if (newRefCount <= 1)
+            throw new InvalidOperationException("Cannot add a reference for an object already released. AddReference/Release pair must match.");
+        return newRefCount;
+    }
+
+    /// <inheritdoc cref="IReferencable.Release()" />
+    public virtual uint Release()
+    {
+        uint newRefCount = Interlocked.Decrement(ref _refCount);
+        if (newRefCount == 0)
+        {
+            try
+            {
+                Destroy();
+            }
+            finally
+            {
+                // Reverse back the counter if there are any exceptions in the destroy method
+                Interlocked.Exchange(ref _refCount, newRefCount + 1);
+            }
+        }
+        else if (newRefCount < 0)
+        {
+            throw new InvalidOperationException("Cannot release an object that doesn't have active reference. AddReference/Release pair must match.");
+        }
+
+        return newRefCount;
+    }
+
     public override string ToString()
     {
         return $"{GetType().Name}: {Id}";
     }
+
+    /// <summary>
+    /// Releases unmanaged and - optionally - managed resources
+    /// </summary>
+    protected abstract void Destroy();
 }
diff --git a/src/Alimer/Assets/IAsset.cs b/src/Alimer/Assets/IAsset.cs
@@ -0,0 +1,20 @@
+// Copyright (c) Amer Koleci and Contributors.
+// Licensed under the MIT License (MIT). See LICENSE in the repository root for more information.
+
+namespace Alimer.Assets;
+
+/// <summary>
+/// Base intefface for Asset.
+/// </summary>
+public interface IAsset : IReferencable
+{
+    /// <summary>
+    /// Gets the unique identifier for this asset.
+    /// </summary>
+	Guid Id { get; }
+
+    /// <summary>
+    /// Gets the asset name.
+    /// </summary>
+    string Name { get; }
+}
diff --git a/src/Alimer/Assets/Image.cs b/src/Alimer/Assets/Image.cs
@@ -125,10 +125,8 @@ private Image(in ImageDescription description, ReadOnlySpan<byte> source)
     /// <inheritdoc/>
     public void Dispose()
     {
-        if (_data != null)
-        {
-            NativeMemory.Free(_data);
-        }
+        Destroy();
+        GC.SuppressFinalize(this);
     }
 
     /// <summary>
@@ -287,6 +285,15 @@ public static unsafe Image FromMemory(Span<byte> data, int channels = 4, bool sr
         }
     }
 
+    /// <inheritdoc/>
+    protected override void Destroy()
+    {
+        if (_data != null)
+        {
+            NativeMemory.Free(_data);
+        }
+    }
+
     private static void SetupImageArray(byte* pixels, nuint memorySize, in ImageDescription description, ImageData[] levels)
     {
         Debug.Assert(pixels != null);
diff --git a/src/Alimer/DisposableObject.cs b/src/Alimer/DisposableObject.cs
@@ -6,17 +6,6 @@
 
 namespace Alimer;
 
-/// <summary>
-/// Base interface for a <see cref="IDisposable"/> interface.
-/// </summary>
-public interface IDisposableObject : IDisposable
-{
-    /// <summary>
-    /// Gets <c>true</c> if the object has been disposed; otherwise, <c>false</c>.
-    /// </summary>
-    bool IsDisposed { get; }
-}
-
 /// <summary>
 /// Base class for a <see cref="IDisposable"/> interface.
 /// </summary>
diff --git a/src/Alimer/IDisposableObject.cs b/src/Alimer/IDisposableObject.cs
@@ -0,0 +1,15 @@
+﻿// Copyright (c) Amer Koleci and Contributors.
+// Licensed under the MIT License (MIT). See LICENSE in the repository root for more information.
+
+namespace Alimer;
+
+/// <summary>
+/// Base interface for a <see cref="IDisposable"/> interface.
+/// </summary>
+public interface IDisposableObject : IDisposable
+{
+    /// <summary>
+    /// Gets <c>true</c> if the object has been disposed; otherwise, <c>false</c>.
+    /// </summary>
+    bool IsDisposed { get; }
+}
diff --git a/src/Alimer/IReferencable.cs b/src/Alimer/IReferencable.cs
@@ -0,0 +1,31 @@
+﻿// Copyright (c) Amer Koleci and Contributors.
+// Licensed under the MIT License (MIT). See LICENSE in the repository root for more information.
+
+namespace Alimer;
+
+/// <summary>
+/// Base interface for all objects that use reference-counting lifetime management.
+/// </summary>
+public interface IReferencable
+{
+    /// <summary>
+    /// Gets the reference count of this instance.
+    /// </summary>
+    /// <value>The reference count.</value>
+    uint ReferenceCount { get; }
+
+    /// <summary>
+    /// Increments the reference count of this instance.
+    /// </summary>
+    /// <returns>The new reference count.</returns>
+    uint AddReference();
+
+    /// <summary>
+    /// Decrements the reference count of this instance.
+    /// </summary>
+    /// <returns>The new reference count.</returns>
+    /// <remarks>
+    /// When the reference count reaches 0, the component should release / dispose dependent objects.
+    /// </remarks>
+    uint Release();
+}
diff --git a/src/Alimer/Rendering/Material.cs b/src/Alimer/Rendering/Material.cs
@@ -43,5 +43,6 @@ public void Dispose()
     /// <param name="disposing"><c>true</c> if the method was called from <see cref="Dispose()" />; otherwise, <c>false</c>.</param>
     protected virtual void Dispose(bool disposing)
     {
+        Destroy();
     }
 }
diff --git a/src/Alimer/Rendering/Materials/PhysicallyBasedMaterialFactory.cs b/src/Alimer/Rendering/Materials/PhysicallyBasedMaterialFactory.cs
@@ -23,6 +23,7 @@ protected override BindGroupLayout CreateBindGroupLayout()
             new BindGroupLayoutEntry(new BufferBindingLayout(BufferBindingType.Constant), 0, ShaderStages.Fragment),
             new BindGroupLayoutEntry(new TextureBindingLayout(), 0, ShaderStages.Fragment), // baseColorTexture
             new BindGroupLayoutEntry(new SamplerBindingLayout(SamplerBindingType.Filtering), 0),  // baseColorSampler
+            new BindGroupLayoutEntry(new TextureBindingLayout(), 1, ShaderStages.Fragment), // normalTexture
                                                                                             // Static samplers
             new BindGroupLayoutEntry(SamplerDescriptor.PointClamp, 100, ShaderStages.All),          // SamplerPointClamp
             new BindGroupLayoutEntry(SamplerDescriptor.PointWrap, 101, ShaderStages.All),           // SamplerPointWrap
@@ -62,7 +63,8 @@ protected override BindGroup CreateBindGroup(Material material)
 
         BindGroup bindGroup = _bindGroupLayout.CreateBindGroup(
             new BindGroupEntry(0, _materialBuffer),
-            new BindGroupEntry(0, pbrMaterial.BaseColorTexture ?? System.CheckerTexture),
+            new BindGroupEntry(0, pbrMaterial.BaseColorTexture ?? System.OpaqueWhiteTexture),
+            new BindGroupEntry(0, pbrMaterial.NormalTexture ?? System.DefaultNormalTexture),
             new BindGroupEntry(0, System.DefaultSampler)
         );
 
diff --git a/src/Alimer/Rendering/PhysicallyBasedMaterial.cs b/src/Alimer/Rendering/PhysicallyBasedMaterial.cs
@@ -31,4 +31,13 @@ public PhysicallyBasedMaterial()
 
     [DefaultValue(1.0f)]
     public float OcclusionStrength { get; set; } = 1.0f;
+
+    /// <inheritdoc/>
+    protected override void Destroy()
+    {
+        NormalTexture?.Dispose();
+        MetallicRoughnessTexture?.Dispose();
+        EmissiveTexture?.Dispose();
+        OcclusionTexture?.Dispose();
+    }
 }
diff --git a/src/Alimer/Rendering/RenderSystem.cs b/src/Alimer/Rendering/RenderSystem.cs
@@ -18,10 +18,6 @@ public sealed partial class RenderSystem : EntitySystem<MeshComponent>
     public const int InstanceBindGroupSpace = 1;
     public const int MaterialBindGroupSpace = 0;
 
-    private readonly Texture _blackTexture;
-    private readonly Texture _whiteTexture;
-    private readonly Texture _defaultNormalTexture;
-
     // TODO: Max frames inflight
     // TODO: Material system
     private readonly Dictionary<Type, IGPUMaterialFactory> _gpuMaterialFactories = [];
@@ -47,9 +43,9 @@ public RenderSystem(IServiceRegistry services)
         ShaderSystem = services.GetService<ShaderSystem>();
         MainWindow = services.GetService<Window>();
 
-        _blackTexture = CreateTextureFromColor(Colors.Transparent);
-        _whiteTexture = CreateTextureFromColor(Colors.White);
-        _defaultNormalTexture = CreateTextureFromColor(new Color(0.5f, 0.5f, 1.0f, 0f));
+        OpaqueWhiteTexture = CreateTextureFromColor(Colors.White);
+        TransparentBlackTexture = CreateTextureFromColor(Colors.Transparent);
+        DefaultNormalTexture = CreateTextureFromColor(new Color(0.5f, 0.5f, 1.0f, 0f));
         ReadOnlySpan<uint> pixels = [
             0xFFFFFFFF,
             0x00000000,
@@ -127,6 +123,10 @@ public RenderSystem(IServiceRegistry services)
 
     public Texture? MultisampleColorTexture { get; private set; }
     public Texture? DepthStencilTexture { get; private set; }
+
+    public Texture OpaqueWhiteTexture { get; }
+    public Texture TransparentBlackTexture { get; }
+    public  Texture DefaultNormalTexture { get; }
     public Texture CheckerTexture { get; }
     public Sampler DefaultSampler { get; }
 
@@ -151,10 +151,6 @@ protected override void Dispose(bool disposing)
             MultisampleColorTexture?.Dispose();
             DepthStencilTexture?.Dispose();
 
-            _blackTexture.Dispose();
-            _whiteTexture.Dispose();
-            _defaultNormalTexture.Dispose();
-
             // View
             _viewBuffer.Dispose();
             _viewBindGroup.Dispose();
@@ -293,7 +289,7 @@ private void RenderCamera(RenderPassEncoder passEncoder, CameraComponent camera)
                     // Update per-object data (after set pipeline)
                     //InstanceData drawData = new()
                     //{
-                    //    WorldMatrix = instances.Transforms[0]
+                    //    worldMatrix = instances.Transforms[0]
                     //};
                     //passEncoder.SetPushConstants(0, drawData);
 
@@ -367,7 +363,7 @@ private void UpdateCamera(CameraComponent camera)
     private Texture CreateTextureFromColor(in Color color)
     {
         ReadOnlySpan<uint> pixels = [color.ToRgba()];
-        return Device.CreateTexture2D(pixels, PixelFormat.RGBA8Unorm, 1, 1);
+        return ToDispose(Device.CreateTexture2D(pixels, PixelFormat.RGBA8Unorm, 1, 1));
     }
 
     protected override void OnEntityComponentAdded(MeshComponent component)
diff --git a/src/Alimer/Rendering/UnlitMaterial.cs b/src/Alimer/Rendering/UnlitMaterial.cs
@@ -30,13 +30,10 @@ public UnlitMaterial()
 
     //public bool CastsShadow { get; set; } = true;
 
-    /// <inheritdoc cref="Dispose()" />
-    /// <param name="disposing"><c>true</c> if the method was called from <see cref="Dispose()" />; otherwise, <c>false</c>.</param>
-    protected override void Dispose(bool disposing)
+
+    /// <inheritdoc/>
+    protected override void Destroy()
     {
-        if (disposing)
-        {
-            BaseColorTexture?.Dispose();
-        }
+        BaseColorTexture?.Dispose();
     }
 }
diff --git a/src/assets/Alimer.Assets/Graphics/MaterialAsset.cs b/src/assets/Alimer.Assets/Graphics/MaterialAsset.cs
@@ -10,5 +10,8 @@ namespace Alimer.Assets.Graphics;
 /// </summary>
 public class MaterialAsset : AssetWithSource
 {
-
+    /// <inheritdoc/>
+    protected override void Destroy()
+    {
+    }
 }
diff --git a/src/assets/Alimer.Assets/Graphics/MeshAsset.cs b/src/assets/Alimer.Assets/Graphics/MeshAsset.cs
@@ -30,4 +30,9 @@ public MeshAsset(MeshData data, Material[] materials)
 
     public required MeshData Data { get; set; }
     public required Material[] Materials { get; set; }
+
+    /// <inheritdoc/>
+    protected override void Destroy()
+    {
+    }
 }
diff --git a/src/assets/Alimer.Assets/Graphics/MeshImporter.cs b/src/assets/Alimer.Assets/Graphics/MeshImporter.cs
@@ -266,6 +266,12 @@ public Task<MeshAsset> ImportGLTF(MeshMetadata metadata)
                     //baseColorTexture.TexCoord;
                 }
 
+                if (material.NormalTexture.HasValue)
+                {
+                    Gltf2.MaterialNormalTextureInfo normalTextureInfo = material.NormalTexture.Value;
+                    physicallyBasedMaterial.NormalTexture = GetTexture(gltf, buffers, normalTextureInfo.Index);
+                }
+
                 materials[materialIndex] = physicallyBasedMaterial;
             }
         }
diff --git a/src/assets/Alimer.Assets/Graphics/TextureAsset.cs b/src/assets/Alimer.Assets/Graphics/TextureAsset.cs

Original file line number	Diff line number	Diff line change
`@@ -125,10 +125,8 @@ private Image(in ImageDescription description, ReadOnlySpan<byte> source)`
`125`	`125`	`/// <inheritdoc/>`
`126`	`126`	`public void Dispose()`
`127`	`127`	`{`
`128`		`- if (_data != null)`
`129`		`- {`
`130`		`- NativeMemory.Free(_data);`
`131`		`- }`
	`128`	`+ Destroy();`
	`129`	`+ GC.SuppressFinalize(this);`
`132`	`130`	`}`
`133`	`131`
`134`	`132`	`/// <summary>`
`@@ -287,6 +285,15 @@ public static unsafe Image FromMemory(Span<byte> data, int channels = 4, bool sr`
`287`	`285`	`}`
`288`	`286`	`}`
`289`	`287`
	`288`	`+ /// <inheritdoc/>`
	`289`	`+ protected override void Destroy()`
	`290`	`+ {`
	`291`	`+ if (_data != null)`
	`292`	`+ {`
	`293`	`+ NativeMemory.Free(_data);`
	`294`	`+ }`
	`295`	`+ }`
	`296`	`+`
`290`	`297`	`private static void SetupImageArray(byte* pixels, nuint memorySize, in ImageDescription description, ImageData[] levels)`
`291`	`298`	`{`
`292`	`299`	`Debug.Assert(pixels != null);`
Original file line number	Diff line number	Diff line change
`@@ -43,5 +43,6 @@ public void Dispose()`
`43`	`43`	`/// <param name="disposing"><c>true</c> if the method was called from <see cref="Dispose()" />; otherwise, <c>false</c>.</param>`
`44`	`44`	`protected virtual void Dispose(bool disposing)`
`45`	`45`	`{`
	`46`	`+ Destroy();`
`46`	`47`	`}`
`47`	`48`	`}`