OpenRakis · maximilien-noal · Aug 5, 2026 · Jul 26, 2026 · Aug 5, 2026 · Aug 5, 2026
diff --git a/.github/workflows/dotnet.yml b/.github/workflows/dotnet.yml
@@ -1,26 +1,39 @@
 name: .NET Build
 
-# Trigger the workflow on push or pull request
-on: [push]
+on:
+  push:
+    branches:
+      - main
+      - encoder
+  pull_request:
+    branches:
+      - main
 
 jobs:
   build:
-
     strategy:
       matrix:
         os: [macos-latest, windows-latest, ubuntu-latest]
       fail-fast: false
-    
+
     runs-on: ${{ matrix.os }}
 
     steps:
-    - uses: actions/checkout@v1
-
-    - name: Setup .NET
-      uses: actions/setup-dotnet@v1
-      with:
-        dotnet-version: '10.0.x'
-
-    - name: Build with dotnet
-      working-directory: ./
-      run: dotnet build --configuration Release
+      - uses: actions/checkout@v4
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: "10.0.x"
+
+      - name: Restore
+        working-directory: ./
+        run: dotnet restore
+
+      - name: Build
+        working-directory: ./
+        run: dotnet build --configuration Release
+
+      - name: Test
+        working-directory: ./
+        run: dotnet test --configuration Release --no-build
diff --git a/HnmPlayer/App.cs b/HnmPlayer/App.cs
@@ -1,6 +1,7 @@
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Themes.Fluent;
+using System.Runtime.Versioning;
 
 namespace logo;
 
@@ -11,11 +12,14 @@ public override void Initialize()
         Styles.Add(new FluentTheme());
     }
 
+    [SupportedOSPlatform("windows")]
     public override void OnFrameworkInitializationCompleted()
     {
         if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
         {
-            desktop.MainWindow = new MainWindow();
+            desktop.MainWindow = PlayerLaunchContext.Current.Headless
+                ? new HeadlessCaptureWindow()
+                : new MainWindow();
         }
 
         base.OnFrameworkInitializationCompleted();

diff --git a/HnmPlayer/HeadlessCaptureWindow.cs b/HnmPlayer/HeadlessCaptureWindow.cs
@@ -0,0 +1,34 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Media.Imaging;
+using System.Diagnostics;
+
+namespace logo;
+
+public sealed class HeadlessCaptureWindow : Window
+{
+    public HeadlessCaptureWindow()
+    {
+        Opened += OnOpened;
+    }
+
+    private async void OnOpened(object? sender, EventArgs e)
+    {
+        Debug.Assert(PlayerLaunchContext.Current.Headless, "Headless capture window should only be used in headless mode.");
+        if (string.IsNullOrWhiteSpace(PlayerLaunchContext.Current.InputPath))
+        {
+            throw new InvalidOperationException("Headless mode requires an input path.");
+        }
+
+        if (string.IsNullOrWhiteSpace(PlayerLaunchContext.Current.ScreenshotDirectory))
+        {
+            throw new InvalidOperationException("Headless mode requires a screenshot directory.");
+        }
+
+        string inputPath = PlayerLaunchContext.Current.InputPath;
+        string screenshotDirectory = PlayerLaunchContext.Current.ScreenshotDirectory;
+
+        await HeadlessPlayerRunner.RunAsync(inputPath, screenshotDirectory);
+        Close();
+    }
+}
diff --git a/HnmPlayer/HeadlessPlayerRunner.cs b/HnmPlayer/HeadlessPlayerRunner.cs
@@ -0,0 +1,60 @@
+using Avalonia;
+using Avalonia.Media.Imaging;
+using Avalonia.Platform;
+using System.Diagnostics;
+
+namespace logo;
+
+internal static class HeadlessPlayerRunner
+{
+    public static async Task RunAsync(string inputPath, string screenshotDirectory)
+    {
+        Debug.Assert(!string.IsNullOrWhiteSpace(inputPath), "Input path must not be empty.");
+        Debug.Assert(!string.IsNullOrWhiteSpace(screenshotDirectory), "Screenshot directory must not be empty.");
+
+        Directory.CreateDirectory(screenshotDirectory);
+
+        var engine = new HnmPlaybackEngine();
+        await engine.LoadAsync(inputPath);
+
+        using WriteableBitmap bitmap = new(
+            new PixelSize(HnmPlaybackEngine.FrameWidth, HnmPlaybackEngine.FrameHeight),
+            new Vector(96, 96),
+            Avalonia.Platform.PixelFormat.Bgra8888,
+            AlphaFormat.Opaque);
+
+        int screenshotIndex = 0;
+        SaveScreenshot(engine, bitmap, Path.Combine(screenshotDirectory, FormatScreenshotName(screenshotIndex++)));
+
+        while (true)
+        {
+            HnmStepResult stepResult = engine.Step();
+            if (!stepResult.Advanced)
+            {
+                break;
+            }
+
+            if (stepResult.VisualChanged)
+            {
+                SaveScreenshot(engine, bitmap, Path.Combine(screenshotDirectory, FormatScreenshotName(screenshotIndex++)));
+            }
+        }
+    }
+
+    private static void SaveScreenshot(HnmPlaybackEngine engine, WriteableBitmap bitmap, string path)
+    {
+        engine.RenderCurrentFrame(bitmap);
+        WriteableBitmapToPng(bitmap, path);
+    }
+
+    private static void WriteableBitmapToPng(WriteableBitmap bitmap, string path)
+    {
+        using FileStream stream = File.Create(path);
+        bitmap.Save(stream);
+    }
+
+    private static string FormatScreenshotName(int index)
+    {
+        return $"frame{index:0000}.png";
+    }
+}
diff --git a/HnmPlayer/HnmPlayer.csproj b/HnmPlayer/HnmPlayer.csproj
@@ -14,11 +14,15 @@
         <Compile Include="MainWindow.cs" />
         <Compile Include="CirclesPaletteData.cs" />
         <Compile Include="HnmPlaybackEngine.cs" />
+        <Compile Include="PlayerLaunchContext.cs" />
+        <Compile Include="HeadlessCaptureWindow.cs" />
+        <Compile Include="HeadlessPlayerRunner.cs" />
     </ItemGroup>
 
     <ItemGroup>
         <PackageReference Include="Avalonia" Version="12.0.3" />
         <PackageReference Include="Avalonia.Desktop" Version="12.0.3" />
+        <PackageReference Include="Avalonia.Headless" Version="12.0.3" />
         <PackageReference Include="Avalonia.Themes.Fluent" Version="12.0.3" />
     </ItemGroup>
 </Project>
diff --git a/HnmPlayer/PlayerLaunchContext.cs b/HnmPlayer/PlayerLaunchContext.cs
@@ -0,0 +1,77 @@
+namespace logo;
+
+internal static class PlayerLaunchContext
+{
+    public static PlayerLaunchOptions Current { get; set; } = PlayerLaunchOptions.UiDefault;
+}
+
+public sealed record PlayerLaunchOptions(bool Headless, string? InputPath, string? ScreenshotDirectory)
+{
+    public static PlayerLaunchOptions UiDefault { get; } = new(false, null, null);
+}
+
+internal static class PlayerCommandLineParser
+{
+    public static PlayerLaunchOptions Parse(string[] args)
+    {
+        bool headless = false;
+        string? inputPath = null;
+        string? screenshotDirectory = null;
+
+        for (int i = 0; i < args.Length; i++)
+        {
+            string arg = args[i];
+            switch (arg)
+            {
+                case "--headless":
+                    headless = true;
+                    break;
+                case "--input":
+                    inputPath = ReadValue(args, ref i, arg);
+                    break;
+                case "--screenshot-dir":
+                    screenshotDirectory = ReadValue(args, ref i, arg);
+                    break;
+                default:
+                    throw new InvalidOperationException($"Unknown argument '{arg}'.");
+            }
+        }
+
+        if (!headless)
+        {
+            return PlayerLaunchOptions.UiDefault;
+        }
+
+        if (string.IsNullOrWhiteSpace(inputPath))
+        {
+            throw new InvalidOperationException("Missing required argument --input for headless mode.");
+        }
+
+        if (string.IsNullOrWhiteSpace(screenshotDirectory))
+        {
+            throw new InvalidOperationException("Missing required argument --screenshot-dir for headless mode.");
+        }
+
+        return new PlayerLaunchOptions(
+            true,
+            Path.GetFullPath(inputPath),
+            Path.GetFullPath(screenshotDirectory));
+    }
+
+    private static string ReadValue(string[] args, ref int index, string argName)
+    {
+        if (index + 1 >= args.Length)
+        {
+            throw new InvalidOperationException($"Missing value after {argName}.");
+        }
+
+        index++;
+        string value = args[index];
+        if (string.IsNullOrWhiteSpace(value))
+        {
+            throw new InvalidOperationException($"Argument {argName} requires a non-empty value.");
+        }
+
+        return value;
+    }
+}
diff --git a/HnmPlayer/Program.cs b/HnmPlayer/Program.cs
@@ -1,4 +1,5 @@
 using Avalonia;
+using Avalonia.Headless;
 
 namespace logo;
 
@@ -7,10 +8,23 @@ public static class Program
     [STAThread]
     public static void Main(string[] args)
     {
-        BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
+        PlayerLaunchOptions launchOptions = PlayerCommandLineParser.Parse(args);
+        PlayerLaunchContext.Current = launchOptions;
+        BuildAvaloniaApp(launchOptions).StartWithClassicDesktopLifetime(args);
     }
 
-    public static AppBuilder BuildAvaloniaApp()
-        => AppBuilder.Configure<App>()
-            .UsePlatformDetect();
+    public static AppBuilder BuildAvaloniaApp(PlayerLaunchOptions launchOptions)
+    {
+        AppBuilder builder = AppBuilder.Configure<App>();
+        if (launchOptions.Headless)
+        {
+            builder = builder.UseHeadless(new Avalonia.Headless.AvaloniaHeadlessPlatformOptions());
+        }
+        else
+        {
+            builder = builder.UsePlatformDetect();
+        }
+
+        return builder;
+    }
 }
diff --git a/logo.sln b/logo.sln
@@ -11,6 +11,12 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "UnHsq", "tools\UnHsq\UnHsq.
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HnmPlayer", "HnmPlayer\HnmPlayer.csproj", "{F8DEF2B9-AD93-47AF-B31F-AE852AA7ABD9}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Hnm0Encoder", "tools\Hnm0Encoder\Hnm0Encoder.csproj", "{6162235E-64B9-4E11-8B27-D0BAC2C24382}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HnmEndToEndTests", "tests\HnmEndToEndTests\HnmEndToEndTests.csproj", "{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}"
+EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "tests", "tests", "{0AB3BF05-4346-4AA6-1389-037BE0695223}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -57,11 +63,36 @@ Global
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 		{F8DEF2B9-AD93-47AF-B31F-AE852AA7ABD9}.Release|x86.Build.0 = Release|Any CPU
+		{6162235E-64B9-4E11-8B27-D0BAC2C24382}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{6162235E-64B9-4E11-8B27-D0BAC2C24382}.Debug|Any CPU.Build.0 = Debug|Any CPU
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+		{6162235E-64B9-4E11-8B27-D0BAC2C24382}.Release|x86.Build.0 = Release|Any CPU
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+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Debug|x64.Build.0 = Debug|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Debug|x86.Build.0 = Debug|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Release|x64.ActiveCfg = Release|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Release|x64.Build.0 = Release|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Release|x86.ActiveCfg = Release|Any CPU
+		{7A6B7A63-ED7A-4E1A-9FE1-7E85F8B8D1A4}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
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 	GlobalSection(NestedProjects) = preSolution
 		{0113F160-F445-4A6E-A865-13CD1AC4C956} = {07C2787E-EAC7-C090-1BA3-A61EC2A24D84}
+		{6162235E-64B9-4E11-8B27-D0BAC2C24382} = {07C2787E-EAC7-C090-1BA3-A61EC2A24D84}
 	EndGlobalSection
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