Add Skia InkCanvas integration and refine rendering backends

Zenith.NET.slnx

@@ -3,6 +3,7 @@
     <File Path="sources/Experiments/Directory.Packages.props" />
     <Project Path="sources/Experiments/CornellBox/CornellBox.csproj" />
     <Project Path="sources/Experiments/FluidTank/FluidTank.csproj" />
+    <Project Path="sources/Experiments/InkCanvas/InkCanvas.csproj" />
     <Project Path="sources/Experiments/PlatformDetection/PlatformDetection.csproj" />
   </Folder>
   <Folder Name="/Extensions/">

sources/Directory.Packages.props

@@ -5,7 +5,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageVersion Include="Avalonia" Version="12.1.0" />
+        <PackageVersion Include="Avalonia" Version="12.1.1" />
         <PackageVersion Include="Hexa.NET.ImGui" Version="2.2.9" />
         <PackageVersion Include="Metal.NET" Version="2.4.0" />
         <PackageVersion Include="Microsoft.Maui.Controls" Version="10.0.90" />
@@ -19,9 +19,9 @@
         <PackageVersion Include="Silk.NET.Vulkan.Extensions.EXT" Version="2.23.0" />
         <PackageVersion Include="Silk.NET.Vulkan.Extensions.KHR" Version="2.23.0" />
         <PackageVersion Include="SixLabors.ImageSharp" Version="4.0.0" />
-        <PackageVersion Include="SkiaSharp" Version="4.150.1" />
-        <PackageVersion Include="Slangc.NET" Version="2026.13.1" />
-        <PackageVersion Include="Uno.WinUI" Version="6.6.176" />
+        <PackageVersion Include="SkiaSharp" Version="4.151.0" />
+        <PackageVersion Include="Slangc.NET" Version="2026.14.1" />
+        <PackageVersion Include="Uno.WinUI" Version="6.6.184" />
     </ItemGroup>
 
 </Project>

sources/Experiments/CornellBox/App.cs

@@ -49,9 +49,9 @@ static App()
 
         window = Window.Create(WindowOptions.Default with
         {
+            Size = new(1280, 720),
             API = GraphicsAPI.None,
-            Title = "Cornell Box - Zenith.NET",
-            Size = new(1280, 720)
+            Title = "Cornell Box - Zenith.NET"
         });
         window.Initialize();
         window.Center();
@@ -86,8 +86,8 @@ static App()
 
         camera = new(input, Matrix4x4.CreateTranslation(278.0f, 273.0f, -800.0f))
         {
-            Speed = 240.0f,
-            FarPlane = 2000.0f
+            FarPlane = 2000.0f,
+            Speed = 240.0f
         };
 
         rasterizer = new();

sources/Experiments/FluidTank/App.cs

@@ -44,9 +44,9 @@ static App()
 
         window = Window.Create(WindowOptions.Default with
         {
+            Size = new(1280, 720),
             API = GraphicsAPI.None,
-            Title = "Fluid Tank - Zenith.NET",
-            Size = new(1280, 720)
+            Title = "Fluid Tank - Zenith.NET"
         });
         window.Initialize();
         window.Center();
@@ -86,10 +86,10 @@ static App()
 
         camera = new(input, new(9.2f, 5.3f, -10.8f), new(0.0f, 1.45f, 0.0f))
         {
-            Speed = 4.0f,
             NearPlane = 0.05f,
             FarPlane = 80.0f,
-            Fov = 48.0f
+            Fov = 48.0f,
+            Speed = 4.0f
         };
 
         renderer = new();

sources/Experiments/FluidTank/Assets/Shaders/FluidComposite.slang

@@ -184,9 +184,8 @@ float3 ReconstructNormal(float2 uv, float centerDepth)
     return normal;
 }
 
-float3 SceneAt(float2 uv)
+float3 SceneAt(float2 uv, float depth)
 {
-    float depth = composite.SceneDepth.SampleLevel(composite.Sampler, uv, 0.0).r;
     if (depth <= 0.0)
     {
         float3 rayView = ViewRay(uv);
@@ -198,22 +197,62 @@ float3 SceneAt(float2 uv)
     return composite.SceneColor.SampleLevel(composite.Sampler, uv, 0.0).rgb;
 }
 
+float3 SceneAt(float2 uv)
+{
+    float depth = composite.SceneDepth.SampleLevel(composite.Sampler, uv, 0.0).r;
+
+    return SceneAt(uv, depth);
+}
+
+bool FrameOccludesFluid(FullscreenOutput input, float sceneDepth)
+{
+    if (composite.SceneColor.Load(int3(int2(input.Position.xy), 0)).a < 0.5)
+    {
+        return false;
+    }
+
+    int2 fluidDimensions = int2(composite.Width, composite.Height);
+    int2 baseFluidPixel = int2(floor(input.UV * float2(fluidDimensions) - 0.5));
+    float closestFluidDepth = 0.0;
+
+    for (int y = 0; y < 2; y++)
+    {
+        for (int x = 0; x < 2; x++)
+        {
+            int2 samplePixel = clamp(baseFluidPixel + int2(x, y), int2(0, 0), fluidDimensions - 1);
+            float sampleDepth = composite.Attributes.Load(int3(samplePixel, 0)).w;
+
+            if (sampleDepth > 0.0 && (closestFluidDepth <= 0.0 || sampleDepth < closestFluidDepth))
+            {
+                closestFluidDepth = sampleDepth;
+            }
+        }
+    }
+
+    return closestFluidDepth <= 0.0 || closestFluidDepth >= sceneDepth;
+}
+
 float4 ShadeWater(FullscreenOutput input)
 {
     float2 uv = input.UV;
+    float sceneDepth = composite.SceneDepth.Load(int3(int2(input.Position.xy), 0)).r;
+    float3 scene = SceneAt(uv, sceneDepth);
 
     if (composite.RenderMode == 1)
     {
-        return float4(ToSRGB(ACESFilm(SceneAt(uv))), 1.0);
+        return float4(ToSRGB(ACESFilm(scene)), 1.0);
     }
 
     float fluidDepth = composite.FluidDepth.SampleLevel(composite.Sampler, uv, 0.0).r;
 
     if (fluidDepth <= 0.0)
     {
-        float3 background = SceneAt(uv);
+        return float4(ToSRGB(ACESFilm(scene)), 1.0);
+    }
 
-        return float4(ToSRGB(ACESFilm(background)), 1.0);
+    if (sceneDepth > 0.0 && (fluidDepth >= sceneDepth || FrameOccludesFluid(input, sceneDepth)))
+    {
+        return float4(ToSRGB(ACESFilm(scene)), 1.0);
     }
 
     float thickness = composite.Thickness.SampleLevel(composite.Sampler, uv, 0.0).r;
@@ -222,7 +261,7 @@ float4 ShadeWater(FullscreenOutput input)
 
     if (surfaceConfidence <= 0.01)
     {
-        return float4(ToSRGB(ACESFilm(SceneAt(uv))), 1.0);
+        return float4(ToSRGB(ACESFilm(scene)), 1.0);
     }
 
     float3 normalView = ReconstructNormal(uv, fluidDepth);
@@ -258,7 +297,7 @@ float4 ShadeWater(FullscreenOutput input)
     color += sunSpecular * float3(1.0, 0.94, 0.78);
     color = lerp(color, float3(0.76, 0.92, 0.96), foam * 0.72);
 
-    color = lerp(SceneAt(uv), color, surfaceConfidence);
+    color = lerp(scene, color, surfaceConfidence);
 
     return float4(ToSRGB(ACESFilm(color)), 1.0);
 }

sources/Experiments/FluidTank/Assets/Shaders/FluidSurface.slang

@@ -191,15 +191,16 @@ DepthOutput DepthFS(SurfaceVSOutput input)
     float sphereZ = sqrt(max(1.0 - radiusSquared, 0.0));
     float3 viewPosition = input.CenterView + float3(input.Corner * surface.ParticleRadius, surface.ParticleRadius * 0.62);
     float4 clipPosition = mul(float4(viewPosition, 1.0), surface.Projection);
+    float linearDepth = -viewPosition.z;
 
-    if (OccludedByScene(input, -viewPosition.z))
+    if (OccludedByScene(input, linearDepth))
     {
         discard;
     }
 
     DepthOutput output;
-    output.LinearDepth = -viewPosition.z;
-    output.Attributes = float4(input.Speed, input.Density, sphereZ, 1.0);
+    output.LinearDepth = linearDepth;
+    output.Attributes = float4(input.Speed, input.Density, sphereZ, linearDepth);
     output.DeviceDepth = clipPosition.z / clipPosition.w;
 
     return output;

sources/Experiments/FluidTank/Assets/Shaders/Scene.slang

@@ -1,5 +1,7 @@
 #include "SceneCommon.slang"
 
+static const uint FrameMaterialId = 4;
+
 struct SceneConstants
 {
     float4x4 View;
@@ -115,7 +117,7 @@ FSOutput FSMain(VSOutput input)
     float3 color = diffuse + specular + environment + material.Albedo * material.Emission;
 
     FSOutput output;
-    output.Color = float4(color, 1.0);
+    output.Color = float4(color, input.MaterialId == FrameMaterialId ? 1.0 : 0.0);
     output.LinearDepth = input.ViewDepth;
 
     return output;

sources/Experiments/FluidTank/FluidSimulation.cs

@@ -48,9 +48,7 @@ public FluidSimulation()
         ParticleCount = DamDimensions.X * DamDimensions.Y * DamDimensions.Z;
 
         Vector3 tankExtent = TankMax - TankMin;
-        GridDimensions = new((uint)MathF.Ceiling(tankExtent.X / GridSpacing),
-                             (uint)MathF.Ceiling(tankExtent.Y / GridSpacing),
-                             (uint)MathF.Ceiling(tankExtent.Z / GridSpacing));
+        GridDimensions = new((uint)MathF.Ceiling(tankExtent.X / GridSpacing), (uint)MathF.Ceiling(tankExtent.Y / GridSpacing), (uint)MathF.Ceiling(tankExtent.Z / GridSpacing));
         CellCount = GridDimensions.X * GridDimensions.Y * GridDimensions.Z;
         GridPointCount = (GridDimensions.X + 1) * (GridDimensions.Y + 1) * (GridDimensions.Z + 1);
         pressureParityDispatchCount = (GridDimensions.X + 1) / 2 * GridDimensions.Y * GridDimensions.Z;

sources/Experiments/FluidTank/FluidTankRenderer.cs

@@ -10,6 +10,7 @@ namespace FluidTank;
 internal enum FluidViewMode
 {
     Water,
+
     Particles
 }
 
@@ -109,7 +110,7 @@ public FluidTankRenderer()
 
         fluidDepthPipeline = GraphicsHelper.CreateGraphicsPipeline(surfaceVertexShader, "FluidSurface.slang", "DepthFS", [], new()
         {
-            ColorFormats = [PixelFormat.R32Float, PixelFormat.R16G16B16A16Float],
+            ColorFormats = [PixelFormat.R32Float, PixelFormat.R32G32B32A32Float],
             DepthStencilFormat = PixelFormat.D32FloatS8UInt,
             SampleCount = SampleCount.Count1
         }, RasterizerState.CullNone(), DepthStencilState.DepthReadWrite(), BlendState.Opaque(), PrimitiveTopology.TriangleStrip);
@@ -302,11 +303,7 @@ public void RenderScene(CommandBuffer commandBuffer)
         commandBuffer.Transition(sceneLinearDepth, default, TextureLayout.Undefined, TextureLayout.ColorAttachment);
         commandBuffer.Transition(DepthStencil, default, TextureLayout.Undefined, TextureLayout.DepthStencilAttachment);
 
-        commandBuffer.BeginRenderPass(
-        [
-            ColorAttachment.Clear(sceneColor, new(0.0f, 0.0f, 0.0f, 1.0f)),
-            ColorAttachment.Clear(sceneLinearDepth, Vector4.Zero)
-        ], DepthStencilAttachment.Clear(DepthStencil, 1.0f, 0));
+        commandBuffer.BeginRenderPass([ColorAttachment.Clear(sceneColor, Vector4.Zero), ColorAttachment.Clear(sceneLinearDepth, Vector4.Zero)], DepthStencilAttachment.Clear(DepthStencil, 1.0f, 0));
         commandBuffer.SetPipeline(scenePipeline);
         commandBuffer.SetVertexBuffer(sceneVertexBuffer, 0, 0);
         commandBuffer.SetIndexBuffer(sceneIndexBuffer, 0, IndexFormat.UInt32);
@@ -339,11 +336,7 @@ public void RenderFluid(CommandBuffer commandBuffer)
         commandBuffer.Transition(smoothDepthA, default, TextureLayout.Undefined, TextureLayout.ColorAttachment);
         commandBuffer.Transition(fluidAttributes, default, TextureLayout.Undefined, TextureLayout.ColorAttachment);
 
-        commandBuffer.BeginRenderPass(
-        [
-            ColorAttachment.Clear(smoothDepthA, Vector4.Zero),
-            ColorAttachment.Clear(fluidAttributes, Vector4.Zero)
-        ], DepthStencilAttachment.Clear(reconstructionDepth, 1.0f, 0));
+        commandBuffer.BeginRenderPass([ColorAttachment.Clear(smoothDepthA, Vector4.Zero), ColorAttachment.Clear(fluidAttributes, Vector4.Zero)], DepthStencilAttachment.Clear(reconstructionDepth, 1.0f, 0));
         commandBuffer.SetPipeline(fluidDepthPipeline);
         commandBuffer.SetConstantBuffer(surfaceConstantBuffer, 0);
         commandBuffer.Draw(4, simulation.ParticleCount, 0, 0);
@@ -423,14 +416,12 @@ public void Resize(uint width, uint height)
         uint reconstructionWidth = Math.Max((width + 2) / 3, 1u);
         uint reconstructionHeight = Math.Max((height + 2) / 3, 1u);
         reconstructionDepth = GraphicsHelper.CreateTexture(PixelFormat.D32FloatS8UInt, reconstructionWidth, reconstructionHeight, TextureUsages.DepthStencilAttachment);
-        fluidAttributes = GraphicsHelper.CreateTexture(PixelFormat.R16G16B16A16Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.ColorAttachment);
         smoothDepthA = GraphicsHelper.CreateTexture(PixelFormat.R32Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.Storage | TextureUsages.ColorAttachment);
+        fluidAttributes = GraphicsHelper.CreateTexture(PixelFormat.R32G32B32A32Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.ColorAttachment);
         smoothDepthB = GraphicsHelper.CreateTexture(PixelFormat.R32Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.Storage);
         smoothThicknessA = GraphicsHelper.CreateTexture(PixelFormat.R16Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.Storage | TextureUsages.ColorAttachment);
         smoothThicknessB = GraphicsHelper.CreateTexture(PixelFormat.R16Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.Storage);
-        reflection = App.Context.Capabilities.RayTracingSupported
-            ? GraphicsHelper.CreateTexture(PixelFormat.R16G16B16A16Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.Storage)
-            : null;
+        reflection = App.Context.Capabilities.RayTracingSupported ? GraphicsHelper.CreateTexture(PixelFormat.R16G16B16A16Float, reconstructionWidth, reconstructionHeight, TextureUsages.Sampled | TextureUsages.Storage) : null;
     }
 
     public void Dispose()